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Chemical substance record

Styrene

100-42-5C8H8104.152 g/mol

A vinylarene that is benzene carrying a vinyl group. It has been isolated from the benzoin resin produced by Styrax species. — ChEBI

Safety references

Safety documents & references

2 indexed references
US · NIOSH

Occupational chemical safety guide

Styrene

Read official guide
JP · NITE

Government GHS classification

R05-C-158B-MOE · FY2023

View classification

Find a product-specific SDS

Safety guides and government classification records are not a manufacturer’s SDS. Match supplier, product number, concentration, physical form, region and revision before using a document.

Identity & molecular properties

Source-linked values
CAS number100-42-5ChEBI ↗
Molecular formulaC8H8ChEBI ↗
Molar mass104.152 g/molChEBI ↗
Monoisotopic mass104.0626 DaChEBI ↗
Formal charge0ChEBI ↗
ChEBI identifierCHEBI:27452ChEBI ↗

Cross-source molecular data

PubChem
Molar mass104.15 g/molPubChem ↗
Exact mass104.062600255 DaPubChem ↗
Computed XLogP2.9PubChem ↗
Topological polar surface area (Ų)0PubChem ↗
H-bond donors0PubChem ↗
H-bond acceptors0PubChem ↗
Rotatable bonds1PubChem ↗

PubChem computed values are shown separately from the ChEBI record. An exact InChIKey match was used to connect the records. Molecular descriptors do not describe a supplied product’s purity, particle size or performance.

Names & structural identifiers

Copy any identifier
styrene
styrene
PPBRXRYQALVLMV-UHFFFAOYSA-N
C=Cc1ccccc1
InChI=1S/C8H8/c1-2-8-6-4-3-5-7-8/h2-7H,1H2

Classification & relationships

ChEBI ontology

Roles recorded in ChEBI

mutagenmouse metaboliteplant metabolite

Database role annotations describe reported biological or chemical roles; they are not product approvals or recommendations for use.

Safety classification · Japan

NITE / Japanese government
Japan · FY2023 source classification
Styrene monomer · R05-C-158B-MOE
EndpointReported classification
Hazardous to the aquatic environment (Acute)Category 2
Hazardous to the aquatic environment (Long-term)Category 3

Selected source-reported endpoints. Other endpoints, rationales and conditions remain in the original classification. Missing or unlisted information does not mean non-hazardous. This is not a global classification or transport decision.

Read the original NITE classification

Mass ↔ amount of substance

Calculated from sourced mass
Equivalent amount
0.00960135 mol

Uses 104.152 g/mol from ChEBI. Assumes the substance described by this record; no purity or concentration correction is applied.

Elemental composition

Theoretical mass fractions
C
Carbon · 8 atoms
92.26%
H
Hydrogen · 8 atoms
7.74%

Calculated theoretical mass fractions from the reported formula and PubChem periodic-table atomic masses. These are not assay or purity results.

Research & patent references

Selected source associations
DNA single strand breaks induced by low levels of occupational exposure to styrene: the gap between standards and reality. ↗Journal of environmental pathology, toxicology and oncology : official organ of the International Society for Environmental Toxicology and Cancer · 2002 · PMID 11934013

Sources & record history

Checked 27 Sep 2026
EMBL-EBI ChEBI · CHEBI:27452

Release 255, 9 September 2026. ChEBI three-star (manually annotated) source entry. View original record ↗ · CC BY 4.0

NCBI PubChem · CID 7501 · retrieved 2026-09-27

PubCAS formats source data, connects references and computes explicitly labelled conversions. CAS cross-references are supplied by ChEBI; they do not constitute CAS verification or endorsement.