home edit2 whole TSD November 2002 PDF format - OEHHA

N-NITROSODIMETHYLAMINE
CAS No: 62-75-9
I. PHYSICAL AND CHEMICAL PROPERTIES (From HSDB, 1994)
Molecular weight 74.1
Boiling point 151°C
Melting point
unknown
Vapor pressure 2.7 mm Hg @ 20°C
Air concentration conversion 1 ppm = 3.08 mg/m 3 @ 20°C
II.
HEALTH ASSESSMENT VALUES
Unit Risk Factor: 4.6 E-3 (µg/m 3 ) -1
Slope Factor: 1.6 E+1 (mg/kg-day) -1
[calculated from a cancer potency value derived by RCHAS/OEHHA (CDHS, 1988)]
III.
CARCINOGENIC EFFECTS
Human Studies
Epidemiological studies correlating exposure to N-nitrosodimethylamine (NDMA) and human cancers
are inadequate to establish a causal relationship.
Animal Studies
Terracini et al .(1967) exposed male and female MRC Porton rats to feed containing 0, 2, 5, 10, 20 or
50 ppm for up to 120 weeks. Daily dose rates were calculated based upon observed food
consumption rates of 15 g/day. Most survivors were sacrificed at 104 weeks, with the exception of an
unspecified number of animals which were sacrificed at 120 weeks. Liver tumor incidence data were
grouped into those which occured among animals surviving greater than or less than 60 weeks. No
liver tumors were reported among 29 untreated animals, four of which died before 60 weeks.
Combined incidence data of liver tumors among female rats dying at any time during the course of the
experiment were 0/18, 4/62, 2/5, 15/23, and 10/12 for the 2, 5, 10, 20, and 50 ppm dose groups,
respectively. Significant dose-related increase in incidence of liver tumors and mortality in female rats
was reported (level of significance not stated).
Terracini et al. (1973) exposed 4-5 week old female BALB/c mice to 3 ppm NDMA in drinking water
for up to 80 weeks in a two generation study. The first generation treated group consisted of 62
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