IARC Group 2B — Possibly carcinogenic to humans
CAS: 91-20-3 | IARC source
Safety data sheet documentation for naphthalene (CAS 91-20-3), compiled to REACH Annex II with classification read against the harmonised entry in CLP Annex VI (H351, H302, H400, H410). Two options: a working draft sent by e-mail immediately, or a signed card issued within 72 hours of complete input. The item supplied is a document — MolGod.org does not sell, supply or ship chemical substances.
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Section 9 — physicochemical properties: 11 of 22 established.
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Identity CAS · EC · IUPAC · synonyms · molecular formula · molecular weight
Structure 2D · 3D · SMILES · InChI · InChIKey
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3D model Naphthalene, CAS 91-20-3, molecular formula C10H8, molar mass 128.17 g/mol
Data transcribed from regulatory registers and technical literature, with the source and edition stated. It does not replace the supplier's safety data sheet. Fields without a recorded source are marked as such.
📊 Physicochemical data — CAS 91-20-3
📊Physicochemical properties
Quick Reference
Formula:C10H8
MW:128.17 g/mol
CAS:91-20-3
Appearance:White crystalline flakes ... Plates from ethanol
Odour:Aromatic odor
Detailed Properties
Supplements the “Physical & Chemical Properties (DB)” table below — values already shown there are not repeated.
Rumble, J.R., ed. CRC Handbook of Chemistry and Physics. 105th ed. Boca Raton: CRC Press, 2024. ↗
applies to: Melting point · Boiling point · Water solubility · Density (ρ) · Refractive index (n_D) · Vapor pressure · Flash point · Autoignition temperature · UV λmax · UV εmax · logP (octanol/water) · Specific heat (cp)
DECHEMA, PTB, and BAM. CHEMSAFE - Database of Evaluated Safety Characteristics for the Avoidance of Explosions. Frankfurt am Main: DECHEMA e.V.; Braunschweig/Berlin: Physikalisch-Technische Bundesanstalt and Bundesanstalt fur Materialforschung und -prufung. ↗
applies to: Melting point · Flash point
NIST. Chemistry WebBook, SRD 69. National Institute of Standards and Technology. ↗
applies to: Melting point
NLM. Hazardous Substances Data Bank (HSDB). National Library of Medicine. ↗
applies to: Water solubility
Sangster, J. "Octanol-Water Partition Coefficients of Simple Organic Compounds." Journal of Physical and Chemical Reference Data 18, no. 3 (1989): 1111-1229. ↗
applies to: logP (octanol/water)
Physicochemical values are derived from the independent, peer-reviewed sources listed above.
PubChem. National Center for Biotechnology Information (NIH/NLM), chemical compound database. ↗
applies to: Molecular formula · Molecular weight · LogP (lipophilicity) · IUPAC name · SMILES · InChIKey
DECHEMA, PTB, and BAM. CHEMSAFE - Database of Evaluated Safety Characteristics for the Avoidance of Explosions. Frankfurt am Main: DECHEMA e.V.; Braunschweig/Berlin: Physikalisch-Technische Bundesanstalt and Bundesanstalt fur Materialforschung und -prufung. ↗
applies to: Melting point
NIST. Chemistry WebBook, SRD 69. National Institute of Standards and Technology. ↗
applies to: Melting point
Rumble, J.R., ed. CRC Handbook of Chemistry and Physics. 105th ed. Boca Raton: CRC Press, 2024. ↗
applies to: Melting point · Boiling point · Density · LogP (lipophilicity)
MOLECULE
Per-CAS bibliography (live from 13+ databases)
Sources: db:pubmed (1) · db:Europe PMC (1)
db:pubmed
Pannu AK, Singla V. (2020). "Naphthalene Toxicity in Clinical Practice.". Current drug metabolism. https://doi.org/10.2174/1389200220666191122110036 →
db:Europe PMC
(2000). "Toxicology and carcinogenesis studies of naphthalene (cas no. 91-20-3) in F344/N rats (inhalation studies).".
Regulatory status of the substance
This substance is subject to regulatory requirements: hazardous waste management (BDO — national rule, Poland). Details in the \"Regulatory Status (REACH/ECHA/CLP)\" section and on the SDS. Regulatory information — does not restrict purchase in this store.
🧮 Stoichiometry Calculator
🧪 Chemical Data
CAS Number
91-20-3
Molecular formula
C10H8
Molar mass
128.17 g/mol
IUPAC name (EN)
naphthalene
SMILES
C1=CC=C2C=CC=CC2=C1
InChIKey
UFWIBTONFRDIAS-UHFFFAOYSA-N
📚 Related literature (1 article)
Matched automatically from public bibliographic databases by text similarity. Not curated for this substance, and not part of the safety data sheet.
PubChem. National Center for Biotechnology Information (NIH/NLM), chemical compound database. ↗
applies to: PubChem CID · InChIKey · InChI · SMILES
ECHA. EC Inventory — EINECS, ELINCS, NLP and List Numbers assigned under REACH. Helsinki: European Chemicals Agency. ↗
applies to: EC Number
ChEMBL. European Bioinformatics Institute (EMBL-EBI), bioactivity database. ↗
applies to: ChEMBL
ChemSpider. Royal Society of Chemistry, chemical structure database. ↗
applies to: ChemSpider
Further reading
Publications thematically related to this CAS. They are not the source of any value shown on this card.
Extended Bibliography (7)
★★★★★CANONICAL_PAPERS💰 Paywall (probable)✓ verifiedJia Y; Bahraminejad S; Duan X et al.. 2025. "Discovery of highly potent naphthalene/quinoline-based PAD inhibitors: Structure-activity relationship, selectivity, and cytotoxicity." European journal of medicinal chemistry.link[accessed: 2026-10-11]
★★☆☆☆CROSSREF🔓 OPEN❓ unverifiedAnonymous. "All-Polymer Solar Cells with 9.4% Efficiency from Naphthalene Diimide-Biselenophene Copolymer Acceptor.". https://doi.org/10.1021/acs.chemmater.8b03229.s001.link[accessed: 2026-10-11]CC0 (metadata)
★★☆☆☆CROSSREF🔓 OPEN❓ unverifiedAnonymous. "Bandgap Engineering of Dual Acceptor-Containing Naphthalene Diimide Polymers for All-Polymer Solar Cells.". https://doi.org/10.1021/acssuschemeng.8b05021.s001.link[accessed: 2026-10-11]CC0 (metadata)
★★☆☆☆CROSSREF🔓 OPEN❓ unverifiedAnonymous. "Aqueous-Soluble Naphthalene Diimide-Based Polymer Acceptors for Efficient and Air-Stable All-Polymer Solar Cells.". https://doi.org/10.1021/acsami.9b13812.s001.link[accessed: 2026-10-11]CC0 (metadata)
★★☆☆☆CROSSREF🔓 OPEN❓ unverifiedAnonymous. "Side Chain Engineered Naphthalene Diimide-Based Terpolymer for Efficient and Mechanically Robust All-Polymer Solar Cells.". https://doi.org/10.1021/acs.chemmater.0c04721.s001.link[accessed: 2026-10-11]CC0 (metadata)
★★☆☆☆CROSSREF🔓 OPEN❓ unverifiedAnonymous. "Poly(naphthalene diimide-alt-bithiophene) Prepared by Direct (Hetero)arylation Polymerization for Efficient All-Polymer Solar Cells.". https://doi.org/10.1021/acs.chemmater.8b02160.s001.link[accessed: 2026-10-11]CC0 (metadata)
★☆☆☆☆OPENLIBRARY🔓 OPENNorman Donaldson. 1958. "The chemistry and technology of naphthalene compounds." E. Arnold.link[accessed: 2026-10-08]CC0 (metadata)
📡 Spectroscopy — CAS 91-20-3
NMR spectroscopy — source records
Earlier NMR results on this page remain available: Live Spectra (NMRShiftDB card) and NMR Predictor (literature table).
Structure identity: UFWIBTONFRDIAS-UHFFFAOYSA-N
For each record: MolGod’s status line, then the source record (as retrieved by MolGod), then MolGod’s own checks.
NMR deposited as experimental — measurement details incomplete
The source lists these spectra as experimental but does not report all measurement details; each spectrum states what is missing. Chemical shifts below come from the source record and are not reconstructed.
¹H NMR
¹H NMR — Experimental (measured); not reported by the source: solvent, temperature, spectrometer frequency — nmrshiftdb2:spectrum:30001113
δ (ppm)
Assignment (atoms)
Multiplicity
Assignment quality
7.38
H5 H6 H7 H8
not reported by the source
group
7.68
H1 H2 H3 H4
not reported by the source
group
Values taken by the source from a reference book (secondary source).
Source
nmrshiftdb2
Spectrum ID
30001113
Solvent
not reported by the source
Temperature (K)
not reported by the source
Frequency (MHz)
not reported by the source
Publication
Weinheim VCH Horst Friebolin Ein- und zweidimensionale NMR-Spektroskopie. eine Einführung 1992
Method
Source measurement type: not declared
Retrieved
2026-09-30T01:44:12Z
MolGod verification
experimental candidate by rule NMR-MEASCALC-1
Assignments
group 2
¹H NMR — Experimental (measured); not reported by the source: temperature — nmrshiftdb2:spectrum:30001114
δ (ppm)
Assignment (atoms)
Multiplicity
Assignment quality
7.38
H5 H6 H7 H8
not reported by the source
group
7.68
H1 H2 H3 H4
not reported by the source
group
Values taken by the source from a reference book (secondary source).
Source
nmrshiftdb2
Spectrum ID
30001114
Solvent
TETRACHLORO-METHANE (CCl4)
Temperature (K)
not reported by the source
Frequency (MHz)
60
Publication
Philadelphia Sadtler Research Laboratories, Inc. W.W.Simons; M.Zanger The Sadtler Guide to NMR Spectra 1972
Method
Source measurement type: not declared
Retrieved
2026-09-30T01:44:12Z
MolGod verification
experimental candidate by rule NMR-MEASCALC-1
Assignments
group 2
¹³C NMR
¹³C NMR — Experimental (measured); not reported by the source: solvent, temperature, spectrometer frequency — nmrshiftdb2:spectrum:30001111
δ (ppm)
Assignment (atoms)
Multiplicity
Assignment quality
125.6
C7 C8 C9 C10
D
ambiguous
125.6
C7 C8 C9 C10
D
ambiguous
127.7
C3 C4 C5 C6
D
group
133.3
C1 C2
S
group
Values taken by the source from a reference book (secondary source).
Source
nmrshiftdb2
Spectrum ID
30001111
Solvent
not reported by the source
Temperature (K)
not reported by the source
Frequency (MHz)
not reported by the source
Publication
New York Thieme Verlag Stefan Berger; S. Braun; H.-O. Kalinowski 13-C-NMR-Spektroskopie 1984
Method
Source measurement type: not declared
Retrieved
2026-09-30T01:44:12Z
MolGod verification
experimental candidate by rule NMR-MEASCALC-1
Assignments
group 2, ambiguous 2
Calculated / predicted NMR — not experimental measurements
Values below are calculated, not measured.
¹³C NMR
¹³C NMR — Predicted by ACD/Labs C+H NMR Predictors and DB, 2020.1.0 (calculated, not measured) — nmrshiftdb2:spectrum:60021030
δ (ppm)
Assignment (atoms)
Multiplicity
Assignment quality
126.08
C7 C8 C9 C10
D
group
128.04
C3 C4 C5 C6
D
group
133.68
C1 C2
S
group
Source
nmrshiftdb2
Spectrum ID
60021030
Solvent
not reported by the source
Temperature (K)
not reported by the source
Frequency (MHz)
not reported by the source
Publication
not reported by the source
Method
Source method: ACD/Labs C+H NMR Predictors and DB, 2020.1.0 (calculated)
Retrieved
2026-09-30T01:44:12Z
MolGod verification
calculated (prediction) by rule NMR-MEASCALC-1
Assignments
group 3
¹³C NMR — Predicted by HOSE code using nmrshiftdb2 data (calculated, not measured) — nmrshiftdb2:spectrum:70148232
δ (ppm)
Assignment (atoms)
Multiplicity
Assignment quality
125.6
C7 C8 C9 C10
D
group
127.7
C3 C4 C5 C6
D
group
133.3
C1 C2
S
group
Source
nmrshiftdb2
Spectrum ID
70148232
Solvent
not reported by the source
Temperature (K)
not reported by the source
Frequency (MHz)
not reported by the source
Publication
not reported by the source
Method
Source method: HOSE code using nmrshiftdb2 data (calculated)
Retrieved
2026-09-30T01:44:12Z
MolGod verification
calculated (prediction) by rule NMR-MEASCALC-1
Assignments
group 3
Symmetry-equivalent atom groups (MolGod, from the three-dimensional structure)
National Institute of Standards and Technology. 2024. "NIST Chemistry WebBook, SRD 69." Gaithersburg, MD: NIST. Accessed 2025-01-01. ↗
Spectral Database for Organic Structure Determination (SDBS). 2024. National Institute of Advanced Industrial Science and Technology (AIST), Japan. Accessed 2025-01-01. ↗
Ulrich, Eldon L., Hideo Akutsu, John F. Doreleijers, Yoko Harano, Yannis E. Ioannidis, Jundong Lin, Miron Livny, et al. 2008. "BioMagResBank." Nucleic Acids Research 36 (D1): D402–D408. [DOI ↗]
Horai, Hisayuki, Masanori Arita, Shigehiko Kanaya, Yoshito Nihei, Tasuku Ikeda, Kazuhiro Suwa, Yuya Ojima, et al. 2010. "MassBank: A Public Repository for Sharing Mass Spectral Data for Life Sciences." Journal of Mass Spectrometry 45 (7): 703–714. [DOI ↗]
Linstrom, P.J., and W.G. Mallard, eds. 2024. NIST Chemistry WebBook, NIST Standard Reference Database Number 69. Gaithersburg, MD: National Institute of Standards and Technology. ↗
McDonald, M. Shane, Mike McAvoy, and Ajit Bhalerao. 1988. "JCAMP-DX: A Standard Form for Exchange of Infrared Spectra in Computer Readable Form." Applied Spectroscopy 42 (1): 151–162. [DOI ↗]
PubChem. 2024. "PubChem Compound Database." National Library of Medicine, National Institutes of Health. Accessed 2025-01-01. ↗
Spectra are fetched on demand from 9 sources. Each spectrum is stored in our database — the next time it is opened there are zero requests to the external API. Download JCAMP-DX / CSV / PNG for every spectrum without searching.
Type of data: Experimental (measured); not reported by the source: solvent, temperature, spectrometer frequency Basis: these values match NMRShiftDB record nmrshiftdb2:30001113, nmrshiftdb2:30001114; type as classified by MolGod from that record.
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🔗 Source
About the downloads (Type of data: Experimental (measured); not reported by the source: solvent, temperature, spectrometer frequency) JCAMP: the NMRShiftDB file as received (JCAMP-DX 5.01 text). It is a peak list: chemical shift in ppm. MolGod adds header lines stating the type of data; the values are unchanged. CSV: the same peak list in two columns. The second column repeats the shift value; it is not a signal intensity. Lines starting with # state the type of data. PNG: a picture of the plot above, with the type of data written on it. Use: where signals are expected or were reported (chemical shift positions). Not included or guaranteed: intensities, multiplicities, coupling constants, line shapes, and solvent or temperature unless stated. A predicted list is not a measurement and cannot serve as a reference spectrum for identity or purity testing. Downloads become active after Show.
Data is fetched once (JCAMP-DX parser) and stored in the plugin's local database. No duplicate downloads, no NIST queries on subsequent openings. Licences respected (only a deep link plus our own visualisation is published).
Data retrieved live from multiple sources (priority chain). JCAMP-DX / CSV / PNG available for download under each spectrum.
IR — Fourier-transform infrared
Loading IR — Fourier-transform infrared…
MS — Mass spectrometry (EI 70eV)
Loading MS — Mass spectrometry (EI 70eV)…
NMR — literature reference values (tabulated)
Tabulated reference values (1H and 13C) for CAS 91-20-3. Literature sources: Gottlieb 1997, Pretsch 2009, Silverstein 2014.
Reference data from the literature. Verify against a reference spectrum before analytical use.
1H NMR (CDCl3)
δ (ppm)
Multiplicity
Integration
J (Hz)
Assignment
7.81
m
4
—
H-1,4,5,8 (alpha)
7.45
m
4
—
H-2,3,6,7 (beta)
Data source: Pretsch 2009; SDBS
Type of data: values cited from Pretsch 2009; SDBS; the record does not state whether each value was measured or calculated (may be measured or calculated).
13C NMR (CDCl3)
δ (ppm)
Multiplicity
Integration
J (Hz)
Assignment
133.50
s
—
—
C-4a,8a
128.00
s
—
—
C-1,4,5,8
125.80
s
—
—
C-2,3,6,7
Data source: Pretsch 2009; SDBS
Type of data: values cited from Pretsch 2009; SDBS; the record does not state whether each value was measured or calculated (may be measured or calculated).
Bibliography (Chicago author-date)
Aue, W. P., E. Bartholdi, and R. R. Ernst. 1976. "Two-Dimensional Spectroscopy. Application to Nuclear Magnetic Resonance." Journal of Chemical Physics 64 (5): 2229–2246. [DOI]
Bodenhausen, Geoffrey, and D. J. Ruben. 1980. "Natural Abundance Nitrogen-15 NMR by Enhanced Heteronuclear Spectroscopy." Chemical Physics Letters 69 (1): 185–189.
Bax, Ad, and Donald G. Davis. 1985. "MLEV-17-Based Two-Dimensional Homonuclear Magnetization Transfer Spectroscopy." Journal of Magnetic Resonance 65 (2): 355–360.
Gottlieb, Hugo E., Vadim Kotlyar, and Abraham Nudelman. 1997. "NMR Chemical Shifts of Common Laboratory Solvents as Trace Impurities." Journal of Organic Chemistry 62 (21): 7512–7515. [DOI]
Harris, Robin K., Edwin D. Becker, Sonia M. Cabral de Menezes, Pierre Granger, Roy E. Hoffman, and Kurt W. Zilm. 2008. "Further Conventions for NMR Shielding and Chemical Shifts (IUPAC Recommendations 2008)." Pure and Applied Chemistry 80 (1): 59–84. [DOI]
Fulmer, Gregory R., Alexander J. M. Miller, Nathaniel H. Sherden, Hugo E. Gottlieb, Abraham Nudelman, Brian M. Rosen, Virgil Percec, and Paul J. Chirik. 2010. "NMR Chemical Shifts of Common Laboratory Solvents as Trace Impurities." Organometallics 29 (9): 2176–2179. [DOI]
Levitt, Malcolm H. 2008. Spin Dynamics: Basics of Nuclear Magnetic Resonance. 2nd ed. Chichester: Wiley. ISBN 978-0-470-51117-6
Friebolin, Horst. 2010. Basic One- and Two-Dimensional NMR Spectroscopy. 5th ed. Weinheim: Wiley-VCH. ISBN 978-3-527-32782-9
Berger, Stefan, and Siegmar Braun. 2004. 200 and More NMR Experiments: A Practical Course. Weinheim: Wiley-VCH. ISBN 978-3-527-31067-8
Sanders, Jeremy K. M., and Brian K. Hunter. 1993. Modern NMR Spectroscopy: A Guide for Chemists. 2nd ed. Oxford: Oxford University Press. ISBN 978-0-19-855514-8
Bovey, Frank A., and Peter A. Mirau. 1996. Nuclear Magnetic Resonance Spectroscopy. 2nd ed. San Diego: Academic Press. ISBN 978-0-12-119765-8
Becker, Edwin D. 2000. High Resolution NMR: Theory and Chemical Applications. 3rd ed. San Diego: Academic Press. ISBN 978-0-12-084660-9
Field, Leslie D., Sev Sternhell, and John R. Kalman. 2013. Organic Structures from Spectra. 5th ed. Chichester: Wiley. ISBN 978-1-118-32498-1
🧮 DFT vs experiment comparison (IR)
Overlay of the experimental IR spectrum on the theoretically calculated spectrum using the B3LYP/6-31G* method (scaling factor 0.9614, Scott & Radom 1996).
Experimental DFT (theoretical)
Full theoretical data (geometry, frequencies): NIST CCCBDB ↗
📚 Bibliography (Chicago)
Becke, Axel D. 1993. "Density-Functional Thermochemistry. III. The Role of Exact Exchange." Journal of Chemical Physics 98 (7): 5648–5652. Definition of the B3LYP functional.
Scott, Anthony P., and Leo Radom. 1996. "Harmonic Vibrational Frequencies: An Evaluation of Hartree–Fock, Møller–Plesset, Quadratic Configuration Interaction, Density Functional Theory, and Semiempirical Scale Factors." Journal of Physical Chemistry 100 (41): 16502–16513. Scaling factors for DFT (e.g., 0.9614 for B3LYP/6-31G*).
Merrick, Jeffrey P., Damian Moran, and Leo Radom. 2007. "An Evaluation of Harmonic Vibrational Frequency Scale Factors." Journal of Physical Chemistry A 111 (45): 11683–11700. An update to Scott & Radom — scale factors for newer DFT functionals.
Lee, Chengteh, Weitao Yang, and Robert G. Parr. 1988. "Development of the Colle-Salvetti Correlation-Energy Formula into a Functional of the Electron Density." Physical Review B 37 (2): 785–789. The LYP correlation — complements Becke 1993 for B3LYP.
Hehre, Warren J., Robert Ditchfield, and John A. Pople. 1972. "Self-Consistent Molecular Orbital Methods. XII. Further Extensions of Gaussian-Type Basis Sets." Journal of Chemical Physics 56 (5): 2257–2261. Definition of the 6-31G* basis set (split-valence + polarization).
Johnson, Russell D., III, ed. 2022. "NIST Computational Chemistry Comparison and Benchmark Database (CCCBDB)." NIST Standard Reference Database 101, Release 22. https://cccbdb.nist.gov. Benchmark for theoretical values — the fallback link in the widget.
Cramer, Christopher J. 2004. "Essentials of Computational Chemistry: Theories and Models." 2nd ed. Chichester: Wiley. A textbook on DFT methods and vibrational frequency calculations.
Jensen, Frank. 2017. "Introduction to Computational Chemistry." 3rd ed. Chichester: Wiley. Modern computational chemistry — basis sets and methods for vibrational spectra.
Foresman, James B., and Æleen Frisch. 2015. "Exploring Chemistry with Electronic Structure Methods." 3rd ed. Wallingford, CT: Gaussian, Inc. A practical Gaussian guide — IR + Raman + NMR from DFT.
🎓 Spectrum interpretation guide (for students)
Explanations of every band in the spectrum — why it appears where it does, and what it indicates about the structure.
IR (infrared) (3 peaks)
The IR (infrared) spectrum contains 3 structurally identified bands (out of 5 detected in total: 2 outside recognised ranges). The analysis below explains what each one means structurally and why it appears in that particular range.
C–H out-of-plane bend (aromatic substitution pattern)aromatic_sub● medium
Band "C–H out-of-plane bend (aromatic substitution pattern)" appears in cases: 778.0 cm⁻¹ (strong (s)). The functional group is identified based on its characteristic range (Pavia/Silverstein) — the precise physical mechanism depends on the nearest chemical neighbors.
C=C aromatic ring stretcharomatic● medium
Band "C=C aromatic ring stretch" appears in cases: 1,506.0 cm⁻¹ (weak (w)). Aromatic C=C bands at 1450–1600 cm⁻¹ plus out-of-plane bands at 690–900 cm⁻¹ allow the substitution pattern (ortho/meta/para) to be determined.
📚 Bibliography (Chicago)
Field, Leslie D., Sev Sternhell, and John R. Kalman. 2013. "Organic Structures from Spectra." 5th ed. Chichester: Wiley. A student problem-set textbook (interpretation guide companion).
Williams, Dudley H., and Ian Fleming. 2008. "Spectroscopic Methods in Organic Chemistry." 6th ed. London: McGraw-Hill. A classic of narrative spectral interpretation — explains "why the peak is here".
Crews, Phillip, Jaime Rodríguez, and Marcel Jaspars. 2009. "Organic Structure Analysis." 2nd ed. New York: Oxford University Press. A workflow for multi-parameter structural interpretation.
McLafferty, Fred W., and František Tureček. 1993. "Interpretation of Mass Spectra." 4th ed. Mill Valley, CA: University Science Books. MS fragmentation mechanisms — McLafferty rearrangement, m/z 29 = CHO.
Reusch, William. 2013. "Virtual Textbook of Organic Chemistry: Spectroscopy." East Lansing, MI: Michigan State University. https://www2.chemistry.msu.edu/faculty/reusch/VirtTxtJml/Spectrpy/spectro.htm. An open educational guide to IR/NMR/MS/UV — ideal for explaining functional groups.
Hesse, Manfred, Herbert Meier, and Bernd Zeeh. 2007. "Spektroskopische Methoden in der organischen Chemie." 8th ed. Stuttgart: Thieme. The standard German textbook on spectral interpretation.
Lampman, Gary M., Donald L. Pavia, George S. Kriz, and James R. Vyvyan. 2010. "Spectroscopy." 4th ed. Belmont, CA: Cengage Learning. A workbook with integrated interpretive narratives.
Kalsi, P. S. 2010. "Spectroscopy of Organic Compounds." 6th ed. New Delhi: New Age International. A complete textbook on IR/NMR/MS/UV spectral interpretation.
🔎 Spectrum Search (JCAMP-DX)
Upload a JCAMP-DX file (.jdx, .dx, .jcm) — the system will calculate the cosine similarity against all spectra in the database and display the TOP 10 matches.
📚 Bibliography (Chicago)
McLafferty, Fred W., ed. 2018. Wiley Registry of Mass Spectral Data. 11th ed. Hoboken, NJ: Wiley. A reference MS library (~775k spectra).
Stein, Stephen E., and Donald R. Scott. 1994. "Optimization and Testing of Mass Spectral Library Search Algorithms for Compound Identification." Journal of the American Society for Mass Spectrometry 5 (9): 859–866. The cosine + dot-product algorithm of NIST MS Search.
McDonald, Robert S., and Paul A. Wilks Jr. 1988. "JCAMP-DX: A Standard Form for Exchange of Infrared Spectra in Computer Readable Form." Applied Spectroscopy 42 (1): 151–162. The JCAMP-DX specification (extended to 5.01 for NMR/MS).
McLafferty, Fred W., and František Tureček. 1993. "Interpretation of Mass Spectra." 4th ed. Mill Valley, CA: University Science Books. Cosine-similarity matching and MS fragmentation — the foundation of the search algorithm.
Sumner, Lloyd W., Alexander Amberg, Dave Barrett, Michael H. Beale, Richard Beger, Clare A. Daykin, Teresa W.-M. Fan, et al. 2007. "Proposed Minimum Reporting Standards for Chemical Analysis." Metabolomics 3 (3): 211–221. MSI Level 1-4 — confidence-level standards for spectral matching.
Stein, Stephen E. 1999. "An Integrated Method for Spectrum Extraction and Compound Identification from Gas Chromatography/Mass Spectrometry Data." Journal of the American Society for Mass Spectrometry 10 (8): 770–781. The AMDIS algorithm — deconvolution + library match (NIST).
Lindon, John C., George E. Tranter, and David W. Koppenaal, eds. 2017. "Encyclopedia of Spectroscopy and Spectrometry." 3rd ed. Amsterdam: Academic Press. Encyclopedia entries on spectral library searching.
Smith, Brian C. 2011. "Fundamentals of Fourier Transform Infrared Spectroscopy." 2nd ed. Boca Raton, FL: CRC Press. FT-IR and the JCAMP-DX format for transmission spectra.
Larkin, Peter. 2017. "Infrared and Raman Spectroscopy: Principles and Spectral Interpretation." 2nd ed. Amsterdam: Elsevier. Principles of IR/Raman library matching and peak preprocessing.
Structural properties
Loading structural data...
❓ Frequently asked questions (3)
What is 91-20-3?
91-20-3 (CAS 91-20-3) is a chemical compound. The chemical data comes from PubChem (National Institutes of Health, USA).
Helpful?
What is the CAS number of 91-20-3?
The CAS number for 91-20-3 is 91-20-3. A CAS Registry Number is the standard identifier for a chemical substance in scientific literature and in trade.
Helpful?
How should 91-20-3 be stored?
91-20-3 should be stored as its safety data sheet directs \— typically in a dry, cool, well-ventilated place, away from heat and from materials it is incompatible with.
Helpful?
➕ Suggest a question
Download structure files
Molecular structure files from the PubChem database (NIH). Compatible with Avogadro, PyMOL, Jmol, and ChemDraw.
Cohen ER, Cvitaš T, Frey JG, Holmström B, Kuchitsu K, Marquardt R, Mills I, Pavese F, Quack M, Stohner J, Strauss HL, Takami M, Thor AJ (2007)
g/L ↔ molarity
c (mol/L) = (g/L) / MW
±0.1% (depends on MW precision)
Cohen ER, Cvitaš T, Frey JG, Holmström B, Kuchitsu K, Marquardt R, Mills I, Pavese F, Quack M, Stohner J, Strauss HL, Takami M, Thor AJ (2007)
mmol/L ↔ molarity
c (mol/L) = mmol/L × 10⁻³
Exact
Cohen ER, Cvitaš T, Frey JG, Holmström B, Kuchitsu K, Marquardt R, Mills I, Pavese F, Quack M, Stohner J, Strauss HL, Takami M, Thor AJ (2007)
Celsius ↔ Kelvin
T(K) = t(°C) + 273.15
±0.01 K (ITS-90 scale)
BIPM (Bureau International des Poids et Mesures) (2019)
Celsius ↔ Fahrenheit
T(°F) = T(°C) × 9/5 + 32
±0.1 °F
Thompson A, Taylor BN (2008)
density-corrected % ↔ molarity
c (mol/L) = (%w/w × ρ × 10) / MW, ρ in g/mL
±0.1% when ρ known to 3 decimals
Cohen ER, Cvitaš T, Frey JG, Holmström B, Kuchitsu K, Marquardt R, Mills I, Pavese F, Quack M, Stohner J, Strauss HL, Takami M, Thor AJ (2007)
📚 Bibliography (8 authoritative sources)
Thompson A, Taylor BN (2008). Guide for the Use of the International System of Units (SI). NIST Special Publication 811 · DOI: 10.6028/NIST.SP.811-2008 → Primary SI standard for US scientific usage
Cohen ER, Cvitaš T, Frey JG, Holmström B, Kuchitsu K, Marquardt R, Mills I, Pavese F, Quack M, Stohner J, Strauss HL, Takami M, Thor AJ (2007). Quantities, Units and Symbols in Physical Chemistry — The IUPAC Green Book. RSC Publishing, 3rd ed. · DOI: 10.1039/9781847557889 · ISBN: 978-0-85404-433-7 → Canonical IUPAC guide for chemistry quantities/units
BIPM (Bureau International des Poids et Mesures) (2019). The International System of Units (SI), 9th edition. BIPM · ↗ → International SI definitions (incl. redefined kilogram 2019)
ISO/IEC (2022). Quantities and units — Part 1: General. International Organization for Standardization — ISO 80000-1:2022 · ↗ → General rules for physical quantities and units
ISO/IEC (2019). Quantities and units — Part 9: Physical chemistry and molecular physics. International Organization for Standardization — ISO 80000-9:2019 · ↗ → Concentration / molality / amount-of-substance conventions
Tiesinga E, Mohr PJ, Newell DB, Taylor BN (2021). CODATA recommended values of the fundamental physical constants: 2018. Rev. Mod. Phys. 93(2):025010 · DOI: 10.1103/RevModPhys.93.025010 → Avogadro, gas constant, molar volume (2019 SI revision)
IUPAC (2019). Compendium of Chemical Terminology — the IUPAC Gold Book (online). IUPAC · DOI: 10.1351/goldbook → Definitions of mass fraction, molality, normality, ppm, activity
Mills IM, Cvitaš T, Homann K, Kallay N, Kuchitsu K (1988). Quantities, Units and Symbols in Physical Chemistry. Blackwell Scientific Publications, 1st ed. · ISBN: 0-632-01773-5 → Historical predecessor of IUPAC Green Book
Data limitations notice. The safety information on this page is for reference only and does not replace a full safety data sheet (SDS). Before using the product, consult the manufacturer's current safety data sheet and the GHS/CLP guidance. The CLP classification applies to the pure bulk substance, not to commercial formulations.
GHS/CLP classification — Regulation (EC) No 1272/2008 + UN GHS Rev. 9 (2021).
H410 — Very toxic to aquatic life with long lasting effects
🛡 Precautionary statements (P)
P203 — Obtain, read and follow all safety instructions before use
P264 — Wash thoroughly after handling
✓ Harmonised classification pursuant to Annex VI of the CLP Regulation (EC) 1272/2008 (official, binding classification). Index number: 601-052-00-2.
Reference (Chicago): European Chemicals Agency. "naphthalene, Index No. 601-052-00-2." In Table 3 of Annex VI to Regulation (EC) No 1272/2008 (CLP Regulation), 23rd Adaptation to Technical Progress (harmonised list as of 2026-07-07). Helsinki: European Chemicals Agency, 2026. https://echa.europa.eu/information-on-chemicals/annex-vi-to-clp.
⚠ IARC — Group 2B:
possibly carcinogenic to humans.
(Independent assessment of carcinogenicity evidence by IARC/WHO — supplements the CLP classification above.)
Reference (Chicago): IARC. n.d. IARC Monographs on the Identification of Carcinogenic Hazards to Humans: CAS 91-20-3. Lyon, France: International Agency for Research on Cancer, World Health Organization. https://monographs.iarc.who.int/list-of-classifications/.
Classification from the local MOL-GOD list (snapshot) — unverified against the current IARC list. Verify
Translations: CLP Regulation (EC) 1272/2008, Annexes III and IV. Data: PubChem/NLM.
☢️ Toxicological data (IARC + EPA CTX)
🧬 IARC Carcinogen Classification
IARC classification:
Group 2B
Classification from a local MOL-GOD snapshot — unverified against the current IARC list (verify).
🌍 Ecotoxicology & environmental fate (SDS sec. 8/12)
LC₅₀ (fish):
0.213 mg/L (Melanotaenia fluviatilis, 96 h)
EC₅₀ (Daphnia):
1.6 mg/L (Daphnia magna, 48 h)
EC₅₀ (algae):
10 mg/L (Raphidocelis subcapitata, 48 h)
ED — aquatic organisms (sec. 12.7):
(hormonal) (Oncorhynchus mykiss) [https://doi.org/10.1016/j.cbpc.2006.07.009]; Cortisol (Anguilla anguilla) [https://doi.org/10.1016/S0147-6513(02)00134-3] — source: US EPA ECOTOX (evidence of effect, not a regulatory ED classification).
Source: U.S. EPA ECOTOX Knowledgebase — https://cfpub.epa.gov/ecotox/
Pannu AK, Singla V. (2020). "Naphthalene Toxicity in Clinical Practice.". Current drug metabolism. https://doi.org/10.2174/1389200220666191122110036 [DOI]
(2000). "Toxicology and carcinogenesis studies of naphthalene (cas no. 91-20-3) in F344/N rats (inhalation studies).".
International Agency for Research on Cancer (IARC). 2024. "IARC Monographs on the Identification of Carcinogenic Hazards to Humans." Lyon: IARC. 🔗
U.S. EPA. 2024. "ECOTOX Knowledgebase." Washington, DC: U.S. Environmental Protection Agency. 🔗
ECHA. 2024. "Chemical Safety Assessment." European Chemicals Agency. 🔗
U.S. National Toxicology Program. 2024. Report on Carcinogens. 15th ed. Research Triangle Park, NC: National Institute of Environmental Health Sciences. 🔗
GESTIS. 2024. "GESTIS Substance Database." Institute for Occupational Safety and Health of the German Social Accident Insurance (DGUV). 🔗
U.S. EPA. 2024. "CompTox Chemicals Dashboard." Washington, DC: U.S. Environmental Protection Agency. 🔗
ECHA. 2023. "Regulation (EC) No 1272/2008 on Classification, Labelling and Packaging of Substances and Mixtures (CLP), Annex VI — Harmonised Classification." European Chemicals Agency. 🔗
Leist, Marcel, et al. 2014. "Consensus Report on the Future of Animal-Free Systemic Toxicity Testing." ALTEX 31 (3): 341–356. [DOI]
Hartung, Thomas. 2009. "Toxicology for the Twenty-First Century." Nature 460 (7252): 208–212. [DOI]
Lenga, Robert E., ed. 2008. The Sigma-Aldrich Library of Chemical Safety Data. 2nd ed. Milwaukee: Sigma-Aldrich.
Slikker, William Jr., et al. 2004. "Dose-Dependent Terminal and Tissue Residues After Chronic Exposure." Toxicological Sciences 81 (2): 253–279. [DOI]
Calabrese, Edward J., and Linda A. Baldwin. 2003. "Toxicology Rethinks Its Central Belief." Nature 421 (6924): 691–692. [DOI]
Hodge, Harold C., and J. Harvey Sterner. 1949. "Tabulation of Toxicity Classes." American Industrial Hygiene Association Quarterly 10 (4): 93–96. [DOI]
🚨 Emergency procedure — chemical spillHealth hazard
CAS 91-20-3GHS:H351H302H400H410💨 Ventilation
🥽 PPE — Personal protective equipment
Goggles:Yes
Suit:lab coat
Respirator:type A2 filter (organic vapours) — EN 14387:2004+A1:2008
📦 Small spill (<1L) — absorbent: inert mineral (vermiculite)
⚠️ GENERIC procedure derived from the GHS classification (no curated data for this CAS). Always follow the supplier's current Safety Data Sheet (SDS).
1. Minimize exposure — restrict access by unauthorized persons.
2. Full PPE + respiratory protection; no dust/vapor generation.
3. Sealed, labeled container.
4. Wash the area with water; treat residues and absorbent as hazardous waste.
Additional properties from GHS:
• irritant — avoid skin/eye contact and dust inhalation
• hazardous to the environment — prevent entry into drains, soil and water
🛢️ Large spill (>1L) ⚠️ Hazardous material
1. Evacuate; entry only in full PPE with respiratory protection.
2. Contain; avoid dispersal; follow the site procedure for CMR/STOT substances.
3. Collect mechanically into a labeled UN container; hand over to an authorized company (BDO — national rule, Poland).
4. Report the incident per the OHS procedure; on release to the environment notify the Regional Environmental Inspectorate (WIOŚ) (national rule — Poland).
🩹 First aid
🧴 Skin
1. Remove contaminated clothing.
2. Rinse the skin with plenty of water for ≥15 min.
3. The substance may be absorbed through the skin — monitor symptoms / see a doctor.
👁️ Eyes
1. Rinse with water for ≥15 min, eyelids held open; remove contact lenses.
2. See an ophthalmologist if irritation persists.
🫁 Inhalation
1. Move the casualty to fresh air, comfortable position.
2. If short of breath — oxygen / doctor.
🍽️ Ingestion
1. Rinse the mouth with water; do NOT induce vomiting.
2. Poison Control Center (Poland): +48 42 631 47 24.
🌍 Environment:
Water: High; Soil: Medium; ❌ Do not release into drains; Waste Code: 16 05 06*
📚 Scientific references (Chicago Author-Date) — 8
European Chemicals Agency (ECHA). 2020. Guidance on the Compilation of Safety Data Sheets — Section 6: Accidental Release Measures. ECHA.
[link ↗]
European Parliament and Council. 2008. Regulation (EC) No 1272/2008 (CLP) — Hazard classes and H-statements. Official Journal of the European Union L 353.
[link ↗]
National Institute for Occupational Safety and Health (NIOSH). 2023. Pocket Guide to Chemical Hazards — NIOSH Pocket Guide to Chemical Hazards. CDC.
[link ↗]
U.S. Occupational Safety and Health Administration. 2024. 29 CFR 1910.120 — Hazardous Waste Operations and Emergency Response (HAZWOPER). U.S. Code of Federal Regulations.
[link ↗]
National Fire Protection Association. 2018. NFPA 472: Standard for Competence of Responders to Hazardous Materials/Weapons of Mass Destruction Incidents. NFPA.
[link ↗]
European Parliament and Council. 2012. Directive 2012/18/EU on the Control of Major-Accident Hazards Involving Dangerous Substances (Seveso III). Official Journal of the European Union L 197: 1–37.
[link ↗]
U.S. National Institute for Occupational Safety and Health. 2024. NIOSH Pocket Guide to Chemical Hazards. Centers for Disease Control and Prevention.
[link ↗]
European Chemicals Agency. 2020. Guidance on the Compilation of Safety Data Sheets (SDS), Version 3.1. ECHA.
[link ↗]
Sources: GHS/CLP classification (PubChem/SDS) — generic fallback · ECHA Guidance on SDS (section 6) · NIOSH Pocket Guide.
Indicative data only — in an emergency, always follow the supplier's instructions and local occupational health and safety (OHS) regulations.
⚠️ Visual PPE guide (personal protective equipment)Irritant
🧤 Gloves
Standard nitrile >0.1 mm EN 374-1 typ C
Standard protection against dermal irritation
👁️ Safety Glasses / Goggles
EN 166 D
Protection against solid particles and droplets; basic category
🥼 Lab Coat / Coverall
Standard cotton lab coat EN 13688
Standard buttoned long sleeve
💨 Ventilation
4 ACH(air changes/hour) General laboratory ventilation
4 ACH minimum for open operations; fume hood for concentrated dusts
📚 Scientific references (Chicago Author-Date)
European Committee for Standardization (CEN). 2016. EN 374-1:2016 — Protective gloves against dangerous chemicals and micro-organisms — Part 1: Terminology and performance requirements for chemical risks. CEN, Brussels. EN 374-1:2016. [link ↗] — Classification of chemical-resistant gloves type A/B/C; JKLPT permeation tests
European Committee for Standardization (CEN). 2001. EN 166:2001 — Personal eye-protection — Specifications. CEN, Brussels. EN 166:2001. [link ↗] — Markings: B = medium-energy impact, T = extreme temperatures, 9 = molten metals and hot solids
European Committee for Standardization (CEN). 2009. EN 14605:2005+A1:2009 — Protective clothing against liquid chemicals — Performance requirements for clothing with liquid-tight (Type 3) or spray-tight (Type 4) connections. CEN, Brussels. EN 14605:2009. [link ↗] — Type 3 (jet-tight) and Type 4 (spray-tight) protection against liquid chemicals
National Institute for Occupational Safety and Health (NIOSH). 2017. Recommendations for Chemical Protective Clothing: A Companion to the NIOSH Pocket Guide. U.S. Department of Health & Human Services / CDC. [link ↗] — Practical guide to CPC (chemical protective clothing) selection per substance and exposure scenario
Occupational Safety and Health Administration (OSHA). 2011. Personal Protective Equipment — General requirements. U.S. Department of Labor — 29 CFR 1910.132. 29 CFR 1910.132. [link ↗] — The employer must provide PPE + training + a documented written hazard assessment
ℹ️ Regulatory obligations checklist for CAS 91-20-3.
Status based on: ADR 2025 (Table A), REACH Annex XVII, CLP Annex VI (harmonised classification), hazard class from the m14-spill DB, SVHC, GIS and the Polish OEL list. Principle: no data = no claim (we do NOT declare "no restrictions" without a basis).
✅SDS (Safety Data Sheet) availablefulfilled
How to comply: Requirement: current SDS compliant with Reg. 1907/2006 (REACH) Annex II, 16-section format.
Legal basis: Regulation (EC) No 1907/2006 (REACH) Art. 31 + Annex II
▣Compliant CLP label (pictograms + signal word + H/P)required
How to comply: The label must include: GHS pictograms, the signal word (Danger/Warning), hazard (H) and precautionary (P) statements, and manufacturer details. Required since 2010 (substances) and 2015 (mixtures). For this substance a HARMONISED CLASSIFICATION applies (CLP Annex VI) — see below; it takes precedence over self-classification.
Legal basis: Regulation (EC) No 1272/2008 (CLP) Art. 17-33 + Annex VI (harmonised classification)
❓ADR transport (international agreement)to be verified
How to comply: No ADR data in the MOL-GOD dataset for this CAS number. Do NOT assume there are no restrictions — before shipping, verify the transport classification in ADR 2025 (Table A) and in section 14 of the safety data sheet (SDS).
Legal basis: ADR 2025 European Agreement + Polish Act of 19 August 2011 on the Transport of Dangerous Goods National rules — Poland
🔵REACH registration (>1 t/year EU import)conditional
How to comply: Importers/manufacturers ≥1 tonne/year must register the substance with ECHA (technical dossier + Chemical Safety Report if ≥10 t). Check the ECHA Annex VI / registered substances list.
Legal basis: Regulation (EC) No 1907/2006 (REACH) Art. 5-22
⚪REACH Annex XVII (use/marketing restrictions)not applicable
How to comply: Checked against the harmonised classification (CLP Annex VI): the substance has no CMR category 1A/1B classification, so it is NOT subject to the general ban on sale to the general public under entries 28–30 of Annex XVII. NOTE: specific (non-CMR) Annex XVII entries are not covered by the MOL-GOD dataset (incomplete dataset) — if in doubt, check the consolidated Annex XVII on the ECHA website.
Legal basis: Regulation (EC) No 1907/2006 (REACH) Annex XVII — restrictions on manufacture, placing on the market and use
European Parliament and Council. 2008. Regulation (EC) No 1272/2008 on classification, labelling and packaging of substances and mixtures (CLP). Official Journal of the European Union L 353/1. CLP Regulation 1272/2008. [link ↗] — Classification, labelling and packaging of substances + mixtures (GHS implementation in the EU)
European Parliament and Council. 2006. Regulation (EC) No 1907/2006 concerning the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH). Official Journal of the European Union L 396/1. REACH Regulation 1907/2006. [link ↗] — REACH — registration, evaluation and authorisation of chemicals; SVHC; SDS Annex II
Ministerstwo Rodziny i Polityki Społecznej Rzeczypospolitej Polskiej. 2024. Rozporządzenie Ministra Rodziny i Polityki Społecznej z dnia 4 września 2024 r. w sprawie najwyższych dopuszczalnych stężeń i natężeń czynników szkodliwych dla zdrowia w środowisku pracy. Dziennik Ustaw RP 2024 poz. 1017. National rules — Poland[link ↗] — NDS and NDSCh for ~600 chemical substances — current Polish occupational exposure limits
United Nations Economic Commission for Europe (UNECE). 2025. European Agreement concerning the International Carriage of Dangerous Goods by Road (ADR), 2025 Edition. United Nations, Geneva. ADR 2025. [link ↗] — International agreement on the road transport of dangerous goods — UN numbers, classes, packaging
📚 Consolidated scientific references — Chicago Author-Date 10 sources
References collected from all Safety Hub tabs. CAS: 91-20-3 ·
PubChem ↗
Parlament Europejski i Rada UE. 2008. "Regulation (EC) nr 1272/2008 w sprawie klasyfikacji, oznakowania i pakowania substancji (CLP)." Dz.Urz. UE L 353. [↗]
GHS, Regulations
United Nations Economic Commission for Europe (UNECE). 2021. "Globally Harmonized System of Classification and Labelling of Chemicals (GHS), Ninth Revised Edition." United Nations, Geneva. [↗]
GHS
Goldfrank, Lewis R., Robert S. Hoffman, Mary Ann Howland, et al.. 2019. "Goldfrank's Toxicologic Emergencies, 11th ed.." McGraw-Hill Education, New York. ISBN 978-1-25-985961-8.
First aid, Toxicology
National Institute for Occupational Safety and Health (NIOSH). 2023. "NIOSH Pocket Guide to Chemical Hazards (DHHS Publ. 2005-149)." U.S. Department of Health and Human Services / CDC, Cincinnati, OH. [↗]
First aid, PPE, Toxicology
European Committee for Standardization (CEN). 2016. "EN 374-1:2016 — Protective gloves against dangerous chemicals and micro-organisms." CEN, Brussels. [↗]
PPE
UNECE. 2023. "European Agreement Concerning the International Carriage of Dangerous Goods by Road (ADR 2025)." United Nations, Geneva. [↗]
Disposal, Regulations
National Fire Protection Association (NFPA). 2022. "NFPA 400 — Hazardous Materials Code." NFPA, Quincy, MA. [↗]
Storage
Urben, P.G. (ed.). 2017. "Bretherick's Handbook of Reactive Chemical Hazards, 8th ed.." Butterworth-Heinemann / Elsevier, Oxford. [↗]
Storage
Ministerstwo Klimatu i Środowiska RP. 2023. "Baza danych o produktach i opakowaniach oraz o gospodarce odpadami (BDO)." Ministerstwo Klimatu i Środowiska, Warszawa. National rules — Poland[↗]
Disposal
International Agency for Research on Cancer (IARC / WHO). 2024. "IARC Monographs on the Identification of Carcinogenic Hazards to Humans — List of Classifications." WHO, Lyon. [↗]
Toxicology
Tabs with their own references (Emergency, PPE, Storage, Waste) contain additional bibliographic entries within their respective sections.
Paste a series of replicate measurements (CSV, or one number per line). The calculator computes the mean, standard deviation and 95% CI, and detects outliers (Grubbs + Dixon Q).
Separator: comma, space, tab, new line. Minimum 3 measurements.
📐 Statistical formulas
x̄ = Σxᵢ / n — arithmetic mean
s² = Σ(xᵢ - x̄)² / (n-1) — sample variance
s = √s² — standard deviation
RSD% = (s / x̄) × 100% — relative standard deviation
Plan your entire laboratory project: add experiments with reagents, replicates, and duration. You'll get a Gantt chart, a shopping list (with links to the store!), a budget with a 10% margin, and a GHS risk matrix.
💡 Log in to save projects.
Without logging in you can calculate but not save.
🧪 Solubility and solvent compatibility
Molecule
Naphthalene
Formula
C10H8
logP (XLogP3)
3.30
Mass (g/mol)
128.17
Polarity
Hydrophobic (non-polar)
⚠️ Compatibility per Hansen parameters (δD/δP/δH) — literature values. Indicative data; verify experimentally.
Solvent
Compat.
Ra
Visual
GC-MS
HPLC
Applications
References
Ra < R₀ = good miscibility · Ra < 1,5×R₀ = borderline · above = poor (R₀ — radius of the Hansen sphere of this molecule) For this molecule R₀ = 8..
Solubility theory (applied in compatibility prediction):
Yalkowsky, Samuel H., and Shri C. Valvani. 1980. "Solubility and Partitioning I: Solubility of Nonelectrolytes in Water." Journal of Pharmaceutical Sciences 69 (8): 912–922. https://doi.org/10.1002/jps.2600690814 — General Solubility Equation (GSE): logS = 0.5 − logP − 0.01(MP−25).
Hansen, Charles M. 2007. Hansen Solubility Parameters: A User's Handbook. 2nd ed. CRC Press. https://doi.org/10.1201/9781420006834 — HSP triplet (dD, dP, dH) + Ra formula.
Stefanis, E., and C. Panayiotou. 2008. "Prediction of Hansen Solubility Parameters with a New Group-Contribution Method." Int J Thermophys 29: 568–585. https://doi.org/10.1007/s10765-008-0415-z
Reichardt, Christian, and Thomas Welton. 2011. Solvents and Solvent Effects in Organic Chemistry. 4th ed. Wiley-VCH. https://doi.org/10.1002/9783527632220 — E_T(30) polarity scale, solvatochromism.
Snyder, Lloyd R., Joseph J. Kirkland, and John W. Dolan. 2010. Introduction to Modern Liquid Chromatography. 3rd ed. Wiley. https://doi.org/10.1002/9780470508183 — Eluotropic series, polarity index.
Van Krevelen, D. W., and K. Te Nijenhuis. 2009. Properties of Polymers. 4th ed. Elsevier. https://doi.org/10.1016/B978-0-08-054819-7.X0001-5 — Hoftyzer–Van Krevelen group contribution for dD/dP/dH from SMILES.
Marcus, Yizhak. 1998. The Properties of Solvents. Wiley Series in Solution Chemistry, Vol. 4. ISBN 9780471983699 — Complete tabular set of 250+ solvents (ε, μ, donicity, acceptor numbers).
PubChem Compound Database — CAS 91-20-3 lookup ↗ — logP (XLogP3), water solubility experimental + predicted.
Full bibliography in the REFERENCES accordion (at the bottom of the page) — Chicago Manual of Style 17th ed., Author-Date.
🧮 Solubility calculator
Solubility:—
logS:—
Method:—
⚠️ —
Solubility vs temperature
🌐 Hansen Solubility Sphere (3D)
The closer to the molecule (red sphere), the better the solvent. · Advanced: labels + grid + axes + pulsation.
Your molecule
Good (Ra < R₀)
Borderline (Ra < 1.5×R₀)
Poor (Ra ≥ 1.5×R₀)
Ra < R₀ = good miscibility · Ra < 1,5×R₀ = borderline · above = poor (R₀ — radius of the Hansen sphere of this molecule) For this molecule R₀ = 8..
📚 Data sources: HSP + Ra
Pannu AK, Singla V. (2020). "Naphthalene Toxicity in Clinical Practice.". Current drug metabolism. https://doi.org/10.2174/1389200220666191122110036 [DOI ↗]
(2000). "Toxicology and carcinogenesis studies of naphthalene (cas no. 91-20-3) in F344/N rats (inhalation studies).".
Van Krevelen, D. W., and K. Te Nijenhuis. 2009. Properties of Polymers: Their Correlation with Chemical Structure; Their Numerical Estimation and Prediction from Additive Group Contributions. 4th ed. Amsterdam: Elsevier. [DOI ↗]
Stefanis, Eirini, and Costas Panayiotou. 2008. "Prediction of Hansen Solubility Parameters with a New Group-Contribution Method." International Journal of Thermophysics 29 (2): 568–585. [DOI ↗]
Hansen, Charles M. 2007. Hansen Solubility Parameters: A User's Handbook. 2nd ed. Boca Raton: CRC Press. [DOI ↗]
Martin, Andre, Joel Newburger, and Alan Adjei. 1993. "Extended Hildebrand Solubility Approach: Solubility of Caffeine in Dioxane–Water Mixtures." Journal of Pharmaceutical Sciences 82 (3): 248–252. [DOI ↗]
Barton, Allan F. M. 1991. CRC Handbook of Solubility Parameters and Other Cohesion Parameters. 2nd ed. Boca Raton: CRC Press. ↗
Fedors, R. F. 1974. "A Method for Estimating Both the Solubility Parameters and Molar Volumes of Liquids." Polymer Engineering and Science 14 (2): 147–154. [DOI ↗]
Method: Group Contribution (GC) — rapid δD/δP/δH estimation from logP when experimental data are unavailable. Accuracy ±2 MPa^½. For higher precision → HSPiP software.
Ra < R₀ = good miscibility · Ra < 1,5×R₀ = borderline · above = poor (R₀ — radius of the Hansen sphere of this molecule) Target molecule: δD=19.2,
δP=2,
δH=5.98
📊 Automatically extracted topics from the abstracts of 2 publications for CAS 91-20-3.
Algorithm: TF-IDF (Salton & Buckley 1988) — term frequency × inverse document frequency.
📊 Citation graph for CAS 91-20-3.
Each node = a research paper; an A→B edge = paper A cites B. Data from OpenAlex (Priem 2022).
⚡ Fetch network data
Network built on-demand from the OpenAlex API (24h cache).
Why this page can be checked
Identity
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Data
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Classification
Read against the harmonised entry where one exists, with the index number stated. Self-classification is shown separately and labelled.
Regulatory
Inventory, restriction, authorisation and candidate-list status, each stated individually. Where a status is not established, this page says so — it never says no restrictions apply.
Documentation
Which documents exist, at what review level, in which languages, and when each was issued.
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Nothing on this page is a certification. It is a record you can audit.
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The Gap Report Guarantee
If the available evidence cannot support a defensible document for your CAS number and product specification, we will not invent the missing values. You receive a documented gap report and choose: a refund, store credit, or the report on its own.
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For naphthalene (CAS 91-20-3) the documentation obligation begins before the first shipment. This page sets out what the safety data sheet has to establish.
naphthalene (CAS 91-20-3) at a glance
Substance – naphthalene
CAS number – 91-20-3
EC number – 202-049-5
CLP Annex VI index number – 601-052-00-2
Hazard statements – H351 (suspected of causing cancer); H302 (harmful if swallowed); H400 (very toxic to aquatic life); H410 (very toxic to aquatic life with long lasting effects)
CMR classification – not classified as CMR in the harmonised entry
Documentation issued – safety data sheet in REACH Annex II structure; working draft or signed card
What is supplied – a document. MolGod.org does not sell, supply or ship chemical substances.
What is the CLP classification of naphthalene?
The harmonised classification for CAS 91-20-3 carries 4 hazard statements: H351, H302, H400, H410. In plain terms this means suspected of causing cancer; harmful if swallowed; very toxic to aquatic life; very toxic to aquatic life with long lasting effects. A harmonised entry is binding across the Union — an importer may not soften it, and a self-classification that diverges from it will not survive an enforcement check.
Disposal route and waste classification
Disposal of naphthalene and of its packaging is section 13, and it has to align with the classification: a substance with an aquatic hazard cannot be routed to drain, and the waste code assigned by the holder follows from the hazard profile, not from convenience.
How is naphthalene classified for road, sea and air transport?
Section 14 for CAS 91-20-3 carries the UN number, proper shipping name, class, packing group and environmental hazard where these apply. Where the substance is not dangerous for carriage, the section says so explicitly rather than being left empty — an empty section 14 reads as an omission, not as an absence of hazard.
Which GHS pictograms apply to naphthalene?
The label for naphthalene carries GHS07 (exclamation mark), GHS08 (health hazard), GHS09 (environment), with the signal word Warning. These are not chosen by the supplier: CLP Annex VI states them for CAS 91-20-3, and the precedence rules in Annex I decide which pictogram is dropped when two would say the same thing. A label showing a different set from the register is wrong even if every hazard statement on it is correct.
Identifiers that must agree
The CAS 91-20-3 number and index number 601-052-00-2 are not interchangeable or decorative elements; they serve distinct purposes. The index number connects to the harmonised classification system, whereas the CAS number links to chemical literature. A document containing one without the other requires readers to independently reconstruct this relationship, which may lead to errors during reconstruction.
Who is responsible for REACH compliance for naphthalene?
The responsibility for documentation accompanying naphthalene lies with the entity introducing it into the Union market, rather than with any external supplier. Importers bear the same obligations as manufacturers, including designating an identifiable EU contact in section 1. A non-EU supplier may appoint a sole representative, but this appointment must be established prior to the movement of goods, not in response to subsequent inquiries.
Documentation demand on the EU market
CAS 91-20-3 has a recorded presence on the European trading market, which means documentation for it is requested routinely rather than exceptionally. Substances that move in commerce attract repeat scrutiny: the same sheet is read by successive customers, carriers and authorities, and a defect that survives the first reading rarely survives the tenth.
What must the label for naphthalene contain?
The supply label for naphthalene is generated from the same classification that drives the safety data sheet: pictograms selected by precedence, one signal word derived from the highest hazard class present, and the hazard statements H351, H302, H400… reproduced in full. Where the container is too small to carry the complete set at a legible size, there are lawful ways to handle it and unlawful ones that look identical to a non-specialist.
Why a correct sheet stops being correct
Classification under CLP moves with each Adaptation to Technical Progress. A sheet for CAS 91-20-3 written before the amendment that touched its entry keeps stating a classification the register no longer holds. Nothing in the document announces this — it reads exactly as it did on the day it was issued, which is precisely why revision dates are checked before content.
Which SDS sections decide whether a shipment clears?
A sheet for CAS 91-20-3 is read by number, not as a narrative. Subsections matter as much as sections: an inspector looking for 3.1 will not accept the information folded into a paragraph elsewhere, however complete that paragraph is. Completeness is judged by structure first and content second.
What is the EC number for naphthalene?
Alongside CAS 91-20-3, this substance carries EC number 202-049-5 and Annex VI index 601-052-00-2. European documentation is built around the EC number as often as around the CAS: registration dossiers, the candidate list and customs systems key on it. A safety data sheet quoting only one of the two forces every downstream reader to look up the other.
Where is regulatory status recorded for naphthalene?
Whether CAS 91-20-3 carries obligations beyond classification — candidate list entry, authorisation, restriction — belongs in section 15. Customers increasingly request a written statement on this point before placing an order, and the sheet is the natural place for it.
Can I import naphthalene into the EU?
Placing naphthalene (CAS 91-20-3) on the European Union market requires a safety data sheet compiled to Annex II of REACH before the first consignment moves. For substances listed in CLP Annex VI, customs and carrier checks concentrate on regulated consignments, where the classification stated in section 2 must agree with the harmonised entry in CLP Annex VI under index number 601-052-00-2.
What happens if a consignment of naphthalene is refused?
When a shipment of naphthalene is detained, the expense is typically not the document itself. It is the storage costs, demurrage fees, and the delay incurred by the customer. This financial calculation underscores the importance of verifying the documentation prior to dispatch rather than after receiving a notification from the border.
Protective equipment and exposure controls
Section 8 outlines exposure controls and personal protective equipment (PPE) for naphthalene: appropriate glove materials, eye protection, respiratory protection when warranted by the hazard classification, and any established occupational exposure limits. The choice of glove material is more critical than merely wearing gloves; nitrile gloves are not universally suitable.
Questions about documentation for naphthalene
Can I check whether my existing sheet is still valid?
Yes. A section-by-section reading against Annex II and the current harmonised entry establishes that in one pass, and a sheet that passes is reported as passing.
Do I need a safety data sheet to import naphthalene into the EU?
Yes. A sheet compiled to Annex II of REACH must exist before the first consignment moves, and it must be held by the entity placing the substance on the Union market.
What is the CAS number of naphthalene?
CAS 91-20-3. In CLP Annex VI the same substance carries index number 601-052-00-2, and both identifiers should appear in the documentation.
What hazard statements apply to CAS 91-20-3?
The harmonised entry lists H351, H302, H400, H410. These are binding across the Union and may not be softened by a self-classification.
MolGod.org issues documentation and does not sell, supply or ship chemical substances. CAS 91-20-3 identifies the subject of this document.
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SDS Working Draft
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Full 16-section REACH Annex II structure
Classification against ECHA CLP Annex VI
Public-source data with references
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For internal drafting and supplier review. Unsigned; supplier-specific fields may need completing.
Best for
Seeing what the document will contain before you commit
Comparing what a supplier sent you against the register
Finding the gaps in a sheet you already hold
Preparing an internal file before an export decision
Substances you handle but do not yet sell
Recommended when the document leaves your company✍
Expert-Reviewed SDS
€249.99
Everything in the Working Draft
Reviewed by a competent person under Annex II, section by section
Adapted to your company, product grade and identified use
Destination market and language checked
Transport section reviewed for the mode you request
Five rounds of corrections applied to your instructions
Within 72 hours of receiving complete input.
Best for
Any document that leaves your company
A customer or distributor who asked for the sheet
Paperwork travelling with an export shipment
A sheet an inspector or authority may read
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If you are unsure, read down the left column and stop at the first line that describes your situation.
What the document is for
Working Draft €49.99
Expert-Reviewed €249.99
Internal drafting and review
Yes
Yes
Checking a sheet a supplier sent you
Yes
Yes
Sent to your customer
Not written for this
Yes
Travels with an export shipment
Not written for this
Yes
Read by an inspector or authority
Not written for this
Yes
Adapted to your company, grade and identified use
No
Yes
Signed and dated by the reviewer
No
Yes
When you get it
Immediately after payment
Within 72 hours of complete input
Nothing stops you sending a draft to anyone. "Not written for this" means exactly that: it carries no signature and no fields adapted to your company, so it will not answer the questions the recipient is about to ask.
What the signature means
Who prepares the document
The document is generated by the MolGod engine from ECHA CLP Annex VI and the cited public sources, then read section by section by a qualified scientific reviewer with a degree in chemistry or a related scientific field.
What the review covers
The sheet is read section by section against the REACH Annex II structure. GHS classification and transport entries are checked against the sources cited in the document, and the sheet is adapted to the company, product grade and identified use you provide.
What is NOT verified
We do not test your material and we cannot confirm what is physically in your container: composition, concentration, impurities or manufacturing route. Those come from you and are reproduced as supplied.
What the signature is — and is not
The signature records that a qualified scientific reviewer read the document. It is not a government approval, not an ECHA approval, and not a legal certification — no such certification exists for safety data sheets in the EU. A signature does not by itself make a document legally valid or make your business compliant.
What you receive
A PDF in the 16-section REACH Annex II structure, signed and dated, with version information and a list of anything we could not establish. Five rounds of corrections are included.
Delivery
Within 72 hours of receiving complete input from you. The clock pauses whenever we are waiting on an answer.
Refunds
Full refund before review begins. If the evidence is insufficient, you choose a refund, store credit or a gap report. See the refund policy.
No fabricated-data guarantee.
If the available evidence is insufficient to support a defensible document for this CAS number and your product specification, we will not invent the missing values. You may choose a refund, store credit or a documented gap report.
The supplier placing the substance or mixture on the market remains responsible for ensuring that the final safety data sheet matches the material, its identified uses and their legal role in the supply chain.
📚 Scientific references (Chicago Author-Date) — click to expand
Batch management and laboratory certification standards — 13 independent sources (ICH Q1/Q3/Q6/Q7/Q10 + ISO 17025 + WHO TRS + 21 CFR 211 + EMA + USP + Ph.Eur. + PIC/S + IPEC-PQG).
International Council for Harmonisation (ICH). 2000. "Q7 Good Manufacturing Practice Guide for Active Pharmaceutical Ingredients." ICH Expert Working Group. [link ↗] — GMP for APIs — adopted by EMA, FDA, MHLW
International Organization for Standardization. 2017. "ISO/IEC 17025:2017 General requirements for the competence of testing and calibration laboratories." ISO. [link ↗] — Lab accreditation standard underpinning every CoA
World Health Organization. 2010. "WHO Good Manufacturing Practices for Pharmaceutical Products: Main Principles (WHO Technical Report Series No. 957, Annex 3)." WHO Press. [link ↗] — WHO TRS No. 957 — global reference for GMP
International Council for Harmonisation (ICH). 2003. "ICH Q1A(R2): Stability Testing of New Drug Substances and Products." International Council for Harmonisation. [link ↗] — Source for batch shelf-life and retest dating
International Council for Harmonisation (ICH). 2006. "ICH Q3A(R2): Impurities in New Drug Substances." ICH. [link ↗]
International Council for Harmonisation (ICH). 1999. "ICH Q6A: Specifications for New Drug Substances and Products." ICH. [link ↗] — CoA acceptance-criteria specification standard
International Council for Harmonisation (ICH). 2008. "ICH Q10: Pharmaceutical Quality System." ICH. [link ↗]
U.S. Food and Drug Administration. 2024. "21 CFR Part 211: Current Good Manufacturing Practice for Finished Pharmaceuticals." US Code of Federal Regulations. [link ↗] — US legal mandate (Subpart J — Records and Reports)
European Medicines Agency. 2014. "Guideline on Process Validation for Finished Products — Information and Data to Be Provided EMA/CHMP/CVMP/QWP/BWP/70278/2012." European Medicines Agency. [link ↗]
United States Pharmacopeial Convention. 2024. "United States Pharmacopeia and National Formulary, USP 47-NF 42." USP. [link ↗]
European Pharmacopoeia Commission. 2024. "European Pharmacopoeia 11th Edition." Council of Europe — EDQM. [link ↗]
Pharmaceutical Inspection Co-operation Scheme (PIC/S). 2021. "Guide to Good Manufacturing Practice for Medicinal Products PE 009-15." PIC/S Secretariat, Geneva. [link ↗] — Cross-recognized GMP for 54 inspectorates worldwide
International Pharmaceutical Excipients Council (IPEC) and Pharmaceutical Quality Group (PQG). 2017. "Joint IPEC-PQG Good Manufacturing Practices Guide for Pharmaceutical Excipients." IPEC-Americas. [link ↗] — Excipient-grade CoA standard for non-API ingredients
Model: Gaussian curve centered at λmax, scaled with the Beer-Lambert law A = ε · c · l. Transmittance T = 10^(-A) · 100%.
📚 Scientific references (Chicago Author-Date)
Pannu AK, Singla V. (2020). "Naphthalene Toxicity in Clinical Practice.". Current drug metabolism. https://doi.org/10.2174/1389200220666191122110036 [DOI]
(2000). "Toxicology and carcinogenesis studies of naphthalene (cas no. 91-20-3) in F344/N rats (inhalation studies).".
Linstrom, Peter J., and William G. Mallard, eds. 2023. NIST Chemistry WebBook, NIST Standard Reference Database Number 69. Gaithersburg, MD: National Institute of Standards and Technology. [DOI]
Mayerhöfer, Thomas G., Samir Pahlow, and Jürgen Popp. 2020. "The Bouguer-Beer-Lambert Law: Shining Light on the Obscure." ChemPhysChem 21 (18): 2029-2046. [DOI]
Skoog, Douglas A., F. James Holler, and Stanley R. Crouch. 2017. Principles of Instrumental Analysis. 7th ed. Boston: Cengage Learning. ISBN 978-1-305-57721-3.
Lindon, John C., George E. Tranter, and David W. Koppenaal, eds. 2017. "Encyclopedia of Spectroscopy and Spectrometry." 3rd ed. Amsterdam: Academic Press. ISBN 978-0-12-803224-4.
Field, Leslie D., Sev Sternhell, and John R. Kalman. 2013. "Organic Structures from Spectra." 5th ed. Chichester: Wiley. ISBN 978-1-119-96582-6.
Reusch, William. 2013. "Virtual Textbook of Organic Chemistry: Spectroscopy." East Lansing, MI: Michigan State University.
Lampman, Gary M., Donald L. Pavia, George S. Kriz, and James R. Vyvyan. 2010. "Spectroscopy." 4th ed. Belmont, CA: Cengage Learning. ISBN 978-0-495-88992-9.
Kalsi, P. S. 2010. "Spectroscopy of Organic Compounds." 6th ed. New Delhi: New Age International. ISBN 978-81-224-2032-9.
Williams, Dudley H., and Ian Fleming. 2008. "Spectroscopic Methods in Organic Chemistry." 6th ed. London: McGraw-Hill. ISBN 978-0-07-711559-0.
Sadek, Paul C. 2002. The HPLC Solvent Guide. 2nd ed. Hoboken: Wiley. ISBN 978-0-471-41242-2.
Banwell, Colin N., and Elaine M. McCash. 1994. "Fundamentals of Molecular Spectroscopy." 4th ed. London: McGraw-Hill. ISBN 978-0-07-707976-1.
Perkampus, Heinz-Helmut. 1992. UV-VIS Spectroscopy and Its Applications. Berlin: Springer. https://doi.org/10.1007/978-3-642-77479-9.
Fieser, Louis F. 1949. "Extension of Woodward's Rules for Prediction of Conjugated Diene Absorption." Journal of the American Chemical Society 71 (5): 1854-1857. [DOI]
Woodward, Robert B. 1942. "Structure and the Absorption Spectra of Alpha,Beta-Unsaturated Ketones." Journal of the American Chemical Society 64 (1): 72-75. [DOI]
Beer, August. 1852. "Bestimmung der Absorption des rothen Lichts in farbigen Flüssigkeiten." Annalen der Physik und Chemie 86: 78-88. https://doi.org/10.1002/andp.18521620505.
Lambert, Johann Heinrich. 1760. Photometria. Augsburg: Sumptibus Vidae.
🗃️ database
Kim, Sunghwan, et al. 2023. "PubChem 2023 update." Nucleic Acids Research 51 (D1): D1373-D1380. https://doi.org/10.1093/nar/gkac956. UV spectrum data for CAS 91-20-3 sourced from Hazardous Substances Data Bank (HSDB). PubChem CID: 931. Accessed 2026. λ=320 nm
📚 textbook
Dulski, Thomas R.. 2017. "UV/Visible Molecular Absorption Spectrophotometry." Trace Elemental Analysis of Metals: 177-252. https://doi.org/10.1201/9780203735299-5. [DOI]
📚 textbook
Anonymous. 1989. "Some Applications of Uv and Vis Spectrophotometry." Studies in Analytical Chemistry: 260-303. https://doi.org/10.1016/b978-0-444-98882-9.50012-8. [DOI]
📚 textbook
Anonymous. 1989. "Basis of Spectrophotometry in the Uv and Vis Regions." Studies in Analytical Chemistry: 13-46. https://doi.org/10.1016/b978-0-444-98882-9.50005-0. [DOI]
No public patent metadata was found for this substance in Crossref / OpenAlex at this time. Data will be updated automatically after the next cache refresh (24h).
📚 References (Chicago Author-Date) — click to expand
Pannu AK, Singla V. (2020). "Naphthalene Toxicity in Clinical Practice.". Current drug metabolism. https://doi.org/10.2174/1389200220666191122110036
(2000). "Toxicology and carcinogenesis studies of naphthalene (cas no. 91-20-3) in F344/N rats (inhalation studies).".
World Intellectual Property Organization. 2024. "Patent Cooperation Treaty (PCT)." https://www.wipo.int/pct/.
U.S. Patent and Trademark Office. 2024. "USPTO Patent Public Search." https://ppubs.uspto.gov/.
European Patent Office. 2024. "Espacenet Patent Search." https://worldwide.espacenet.com/.
Newman, David J., and Gordon M. Cragg. 2020. "Natural Products as Sources of New Drugs over the Nearly Four Decades from 01/1981 to 09/2019." Journal of Natural Products 83 (3): 770-803.
Davies, Mark, Michał Nowotka, George Papadatos, et al. 2015. "ChEMBL Web Services: Streamlining Access to Drug Discovery Data and Utilities." Nucleic Acids Research 43 (W1): W612-W620.
Bickerton, G. Richard, Gaia V. Paolini, Jérémy Besnard, Sorel Muresan, and Andrew L. Hopkins. 2012. "Quantifying the Chemical Beauty of Drugs." Nature Chemistry 4 (2): 90-98.
Meanwell, Nicholas A. 2011. "Synopsis of Some Recent Tactical Application of Bioisosteres in Drug Design." Journal of Medicinal Chemistry 54 (8): 2529-2591.
Ertl, Peter, and Ansgar Schuffenhauer. 2009. "Estimation of Synthetic Accessibility Score of Drug-Like Molecules Based on Molecular Complexity and Fragment Contributions." Journal of Cheminformatics 1: 8.
Hopkins, Andrew L., and Colin R. Groom. 2002. "The Druggable Genome." Nature Reviews Drug Discovery 1 (9): 727-730.
Allison, John R., and Mark A. Lemley. 1998. "Empirical Evidence on the Validity of Litigated Patents." AIPLA Quarterly Journal 26 (3): 185-275.
Patani, George A., and Edmond J. LaVoie. 1996. "Bioisosterism: A Rational Approach in Drug Design." Chemical Reviews 96 (8): 3147-3176.
Lerner, Josh. 1994. "The Importance of Patent Scope: An Empirical Analysis." RAND Journal of Economics 25 (2): 319-333.
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📚 REFERENCES (Aggregate bibliography, Chicago Author-Date) 80 items
All scientific sources cited in the accordions above for CAS 91-20-3. Format: Chicago Manual of Style 17th ed., Author-Date system.
AIST. n.d. Spectral Database for Organic Compounds (SDBS): CAS 91-20-3. Tsukuba, Japan: National Institute of Advanced Industrial Science and Technology. https://sdbs.db.aist.go.jp/.
Linstrom, Peter J., and William G. Mallard, eds. n.d. NIST Chemistry WebBook: NIST Standard Reference Database Number 69. Gaithersburg, MD: National Institute of Standards and Technology. https://doi.org/10.18434/T4D303.
PubChem. n.d. PubChem Compound Summary: CAS 91-20-3. Bethesda, MD: National Center for Biotechnology Information (NCBI), National Library of Medicine. https://pubchem.ncbi.nlm.nih.gov/#query=91-20-3.
European Chemicals Agency (ECHA). 2024. "Annex VI to Regulation (EC) No 1272/2008 (CLP) — Harmonised Classification and Labelling." ECHA, Helsinki / Official Journal of the European Union. https://echa.europa.eu/regulations/clp/clp-classification.
National Institute for Occupational Safety and Health (NIOSH). 2017. "Recommendations for Chemical Protective Clothing: A Companion to the NIOSH Pocket Guide." U.S. Department of Health & Human Services / CDC. https://www.cdc.gov/niosh/ncpc/default.html.
Connors, Kenneth A., Gordon L. Amidon, and Valentino J. Stella. 1986. Chemical Stability of Pharmaceuticals: A Handbook for Pharmacists, 2nd ed.. New York: Wiley. https://doi.org/10.1002/0471734683.
Rumble, John R., ed. 2019. CRC Handbook of Chemistry and Physics: 100th Edition. Boca Raton, FL: CRC Press. https://hbcp.chemnetbase.com/.
IARC. n.d. IARC Monographs on the Identification of Carcinogenic Hazards to Humans: CAS 91-20-3. Lyon, France: International Agency for Research on Cancer, World Health Organization. https://monographs.iarc.who.int/list-of-classifications/.
📄 Scientific articles (peer-reviewed)
Stefanis, Emmanuel, and Costas Panayiotou. 2008. "Prediction of Hansen Solubility Parameters with a New Group-Contribution Method." International Journal of Thermophysics 29: 568-585. https://doi.org/10.1007/s10765-008-0415-z.
Stoll, Vincent S., and John S. Blanchard. 1990. "Buffers: Principles and Practice: In Methods in Enzymology, vol. 182." San Diego: Academic Press. https://doi.org/10.1016/0076-6879(90)82008-P.
European Parliament. 2008. "Regulation (EC) No 1272/2008 on Classification, Labelling and Packaging of Substances and Mixtures (CLP)." Official Journal of the European Union L 353: 1–1355.
United Nations. 2021. Globally Harmonized System of Classification and Labelling of Chemicals (GHS). 9th revised ed. ST/SG/AC.10/30/Rev.9. New York and Geneva: United Nations. https://unece.org/ghs-rev9-2021.
United States Pharmacopeial Convention. 2024. "USP <621> Chromatography." In United States Pharmacopeia and National Formulary, USP 47-NF 42. Rockville, MD: USP. https://www.uspnf.com/.
International Organization for Standardization. 2017. "ISO/IEC 17025:2017 General Requirements for the Competence of Testing and Calibration Laboratories." Geneva: ISO. https://www.iso.org/standard/66912.html.
Kolthoff, Izaak Maurits, and Philip J. Elving, eds. 1978. Treatise on Analytical Chemistry, Part I: Theory and Practice. 2nd ed. New York: Wiley-Interscience.
Skoog, Douglas A., F. James Holler, and Stanley R. Crouch. 2018. Principles of Instrumental Analysis. 7th ed. Boston: Cengage Learning.
Christian, Gary D., Purnendu K. Dasgupta, and Kevin A. Schug. 2014. Analytical Chemistry. 7th ed. Hoboken, NJ: Wiley.
International Organization for Standardization. 1994. "ISO 5725-2:1994 Accuracy (Trueness and Precision) of Measurement Methods and Results — Part 2: Basic Method for the Determination of Repeatability and Reproducibility of a Standard Measurement Method." Geneva: ISO. https://www.iso.org/standard/11834.html.
Heckert, N. A., and J. J. Filliben. 2003. "NIST/SEMATECH e-Handbook of Statistical Methods." NIST Handbook 151. Gaithersburg, MD: National Institute of Standards and Technology. https://www.itl.nist.gov/div898/handbook/.
Grubbs, Frank E. 1950. "Sample Criteria for Testing Outlying Observations." Annals of Mathematical Statistics 21 (1): 27–58.
Dixon, Wilfrid J. 1950. "Analysis of Extreme Values." Annals of Mathematical Statistics 21 (4): 488–506.
Snedecor, George W., and William G. Cochran. 1989. Statistical Methods. 8th ed. Ames, IA: Iowa State University Press.
Student [William Sealy Gosset]. 1908. "The Probable Error of a Mean." Biometrika 6 (1): 1–25.
International Organization for Standardization. 2005. "ISO 3534-1:2006 Statistics — Vocabulary and Symbols — Part 1: General Statistical Terms and Terms Used in Probability." Geneva: ISO. https://www.iso.org/standard/40145.html.
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