toxicological profile for malathion - Agency for Toxic Substances and ...

a
Key to
figure
1
2
3
4
5
6
Species
(Strain)
Exposure/
Duration/
Frequency
(Specific Route)
ACUTE EXPOSURE
Systemic
Human
System
Table 3-1 Levels of Significant Exposure to Malathion - Inhalation
NOAEL
(mg/m³)
Less Serious
LOAEL
Serious
(mg/m³) (mg/m³)
Reference
Chemical Form
5-10 min Golz 1959
Resp
21 M 85 M (nasal irritation)
Neurological
65 b Rabbit
(New
Zealand)
6 hr
M 123 M (38% inhibition of RBC
cholinesterase)
Weeks et al. 1977
INTERMEDIATE EXPOSURE
Systemic
Human
Rat
(Sprague-
Dawley)
42 d
2 hr/d
13 wk
5 d/wk
6 hr/d
Neurological
Human 42 d
2 hr/d
Rat
(Sprague-
Dawley)
13 wk
5 d/wk
6 hr/d
Bd Wt
Resp
Bd Wt
2010
85 M
85 M
100
100 c
(hyperplasia of the olfactory
epithelium and of the larynx
epithelium)
450 (22% and 27% decrease in
RBC cholinesterase activity in
males and females,
respectively)
2010 F (70% decrease in plasma
cholinesterase activity)
Golz 1959
Beattie 1994
Golz 1959
Beattie 1994
a The number corresponds to entries in Figure 3-1.
b Used to derive an acute-duration inhalation minimal risk level (MRL) of 0.2 mg/m3; the MRL was derived by dividing the duration-adjusted NOAEL by an uncertainty factor of 100
(10 for animal to human extrapolation; 10 for human variability).
c Used to derive an intermediate-duration inhalation minimal risk level (MRL) of 0.02 mg/m3; the MRL was derived by dividing the duration-adjusted LOAEL by an uncertainty factor of
1000 (10 for animal to human extrapolation; 10 for use of a LOAEL; 10 for human variability).
Bd = body weight; d = day(s); F = Female; hr = hour(s); LOAEL = lowest-observed-adverse-effect level; M = male; mg/m3 = milligram/cubic meter; min = minute(s); NOAEL =
no-observed-adverse-effect level; RBC = red blood cell(s); Resp = respiratory; wk = week(s).