Nitrobenzene CASRN 98-95-3 | IRIS

IRIS

Nitrobenzene

CASRN 98-95-3 | DTXSID3020964

Toxicological Review (PDF) (250 pp, 3.83 M)
IRIS Summary (PDF) (30 pp, 257 K)

Noncancer Assessment

Reference Dose for Oral Exposure (RfD) (PDF) (30 pp, 257 K) Last Updated: 02/06/2009

System	RfD (mg/kg-day)	Basis	PoD	Composite UF	Confidence
Hematologic	2 x 10 ^-3	Increased methemoglobin levels	BMDL (1SD): 1.8 mg/kg-day	1000	Medium

Reference Concentration for Inhalation Exposure (RfC) (PDF) (30 pp, 257 K) Last Updated: 02/06/2009

System	RfC (mg/m³)	Basis	PoD	Composite UF	Confidence
Nervous, Respiratory	9 x 10 ^-3	Bronchiolization of the alveoli and olfactory degeneration	BMCL ₁₀ (HEC): 0.26 mg/m³	30	Medium

Cancer Assessment

Weight of Evidence for Cancer (PDF) (30 pp, 257 K) Last Updated: 02/06/2009

WOE Characterization	Framework for WOE Characterization
Likely to be carcinogenic to humans (Combined route)	Guidelines for Carcinogen Risk Assessment (U.S. EPA, 2005)

Basis:

Under the Guidelines for Carcinogen Risk Assessment (U.S. EPA, 2005a), nitrobenzene is classified as "likely to be carcinogenic to humans" by any route of exposure.
This may be a synopsis of the full weight-of-evidence narrative.

Quantitative Estimate of Carcinogenic Risk from Oral Exposure (PDF) (30 pp, 257 K)

Not Assessed under the IRIS Program.

Quantitative Estimate of Carcinogenic Risk from Inhalation Exposure (PDF) (30 pp, 257 K)

Inhalation Unit Risk: 4 x 10^-5 per µg/m³
Extrapolation Method: Multistage model with linear extrapolation from the POD (LEC10).
Tumor site(s): Urinary, Endocrine, Hepatic
Tumor type(s): Liver hepatocellular adenomas or carcinomas, kidney tubular adenomas or carcinomas, thyroid follicular cell adenomas or carcinomas (CIIT (1993))

Mar 2007: IRIS Toxicological Review of Nitrobenzene (External Review Draft) (Report)

Additional EPA toxicity information may be available by visiting the following sites:

Human Health Benchmarks for Pesticides (HHBP). This database provides human health benchmarks for pesticides that may be present in drinking water.
Office of Pesticide Programs Pesticide Chemical Search. This database provides links to health effects information and registration status for pesticides.
Chemistry Dashboard. This database provides information on chemical structures, experimental and predicted physicochemical, and toxicity data.

You will need Adobe Reader to view some of the files on this page. See EPA's PDF page to learn more.