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

a
Key to
figure
Species
(Strain)
Exposure/
Duration/
Frequency
(Specific Route)
System
Table 3-2 Levels of Significant Exposure to Malathion - Oral
NOAEL
(mg/kg/day)
Less Serious
LOAEL
Serious
(mg/kg/day) (mg/kg/day)
(continued)
Reference
Chemical Form
32
Neurological
Rat
(Sprague-
Dawley)
once
(GO)
1000 F (34% inhibition of RBC
cholinesterase)
Lamb 1994a
33
34
35
36
37
38
39
Rat
(Sprague-
Dawley)
Rat
(Wistar)
8 d
Gd 6-13
1 x/d
(GO)
7 d
1x/d
(F)
138 F
163
276 F (34% inhibition brain AChE) 827 F (convulsions, tremor, ataxia)
411 (dizziness, recurrent
convulsions, and tremors
observed in all rats)
Mathews and Devi 1994
Ojha et al. 1992
Rat once Piramanayagam et al. 1996
1950 M (brain congestion, neuronal
(Wistar) (G)
degeneration and gliosis)
Mouse once Casale et al. 1983
720 M (tremors, fasciculations, 36%
(C57BL/ 6N) (GO)
inhibition brain cholinesterase)
Mouse
(C57BL/ 6N)
4 d
(GO)
240 M (47 and 59% inhibition of
plasma and RBC
cholinesterase, respectively)
Casale et al. 1983
Rabbit
(New
Zealand)
Rabbit
(New
Zealand)
once Vijayakumar and Selvarajan 1990
188 M (50-60% inhibition of brain
(G)
AChE)
once Weeks et al. 1977
12 M 120 M (27% inhibition of RBC
600 M (61% inhibition of RBC
(GO)
cholinesterase)
cholinesterase)