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Arsenic

CAS Number

7440-38-2

Synonym

Arsenic, inorganic; Arsenic black; Arsenic-75; Colloidal arsenic; Gray arsenic; Inorganic arsenic compounds; Metallic arsenic

Occurrence/Use

Wood preservative, herbicide, nonferrous alloys, medicine (leukemia treatment); component of tobacco smoke. Formerly used in optical glass.

Date Added

02/27/1987
Arsenic

Soil Screening

Last CHHSL revision: 
1/2005
CHHSL Comments: 

For chemical-specific screening levels for use in assessing contaminated sites, please see HHRA Note 3 (DTSC HERO). https://www.dtsc.ca.gov/assessingrisk/humanrisk2.cfm

Cancer Potency Information

Latest Criteria: 
California Public Health Goals
Inhalation Unit Risk (μg/cubic meter)-1: 
3.3 E-3
Inhalation Slope Factor (mg/kg-day)-1: 
1.2 E+1
Oral Slope Factor (mg/kg-day)-1: 
9.5 E+0
Comments/References: 

OEHHA 2009. Air Toxics Hot Spots Program Technical Support Document for Cancer Potencies. Appendix B. Chemical-specific summaries of the information used to derive unit risk and cancer potency values. Updated 2011. (Note: arsenic REL for Hot Spots based on 1991 IRIS assessment)

 

OEHHA 2004. Public Health Goal for Arsenic in Drinking Water. Listed as Arsenic.

 

Note: Hot Spots risk assessments use oral arsenic TAC slope factor for oral exposures. P65 use the listed NRSLs. Other risk assessors use 2009 TAC inhalation slope factor for the inhalation route, and the 2004 PHG oral slope factor for the oral route.

Air

Acute RELs

Acute REL (μg/m3): 
0.2
Species: 
Mouse
Acute REL Toxicologic Endpoint: 
Reproductive/ development (decreased fetal weight); altered brain structure and funtion
Acute REL Target Organs: 
Reproductive/ development, cardiovascular system, nervous system
Severity: 
Severe
Last Acute REL Revision: 
July 2014
Acute Reference Exposure Levels Comments: 

8-Hour RELs

8-Hour Inhalation REL (μg/m3): 
0.015
Last 8-Hour REL Revision: 
July, 2014
8-Hour Reference Exposure Levels Comments: 

Chronic REL

Chronic Inhalation REL (μg/m3): 
0.015 (inhalation); 0.0035 μg/kg BW-day (oral)
Chronic Target Organs: 
Reproductive/ development; cardiovascular system; nervous system; lung; skin
Human Data: 
Yes
Last Chronic REL Revision: 
July 2014
Chronic Reference Exposure Levels Comments: 

Proposition 65

Chemical Status

Cancer: 
Currently listed

Cancer

Listed as causing: 
Cancer
Date of Listing: 
02/27/1987
Basis for Listing: 
Labor Code

Safe Harbor Levels

Cancer
No Significant Risk Level (NSRL): 
10 µg/day (except via inhalation)
No Significant Risk Level (NSRL) - Inhalation: 
0.06 µg/day

Comments

Arsenic (inorganic oxides) listed separately.

Water

California Public Health Goals Data

Health Risk Category: 
Carcinogenicity
Public Health Goal (mg/L): 
0.000004
Public Health Goal - Download: 
Cancer Risk at PHG: 
0.000001
MCL value (mg/L): 
0.01
Cancer Risk at MCL: 
0.0025
Last PHG Revision : 
2004
California PHG Comments: 
Solubility of arsenic compounds vary.