Dichlorvos (DDVP) Risk Characterization Document - California ...

Occupational Exposure
The MOSs for the acute exposure of DDVP were 27, 36, and 5 for warehouse workers, PCOs, and
livestock applicators, respectively (Table 23).
The MOSs for non-oncogenic effects from chronic and lifetime exposures were 83 or less for workers
(Table 23).
The lifetime oncogenic risk for workers ranged from 6 x 10 -5 to 9 x 10 -4 .
Residential Exposure
The MOSs ranged from 3 to 8 for acute exposure to home fogger and no-pest strip uses (Table 23).
The MOSs were 33 for adult residents after structural application and 1100 for owners of pets with flea
collars.
The MOS for non-oncogenic effects from chronic exposure was 4 for children after no-pest strip use
(Table 23). The MOSs were 12 and 20 for children and adults after fogger use. The MOSs for
chronic exposures were 125 for structural applications and 500 for pet owners. The MOSs for nononcogenic
effects after lifetime exposure were 10 to 833 (Table 23).
The lifetime oncogenic risk for residents ranged from 6 x 10 -6 to 1 x 10 -3 .
Dietary Exposure
The MOSs for acute dietary exposure of all population subgroups were greater than 300 (Table 24).
Based on the DPR estimate, the MOSs for non-oncogenic effects from chronic exposure of all
population subgroups, except for 1 subgroup, were greater than 100 (Table 24). The MOS was 95 for
children (1-6 years). For the USEPA estimate, all MOSs were greater than 100 (Table 24).
Based on DPR exposure and potency factors, the oncogenic risks for the lifetime exposure level of
0.22 ug/kg-day for the U.S. population were 4 x 10 -5 and 7.7 x 10 -5 for q 1 and q 1 *, respectively. Based
on the USEPA exposure estimate of 0.036 ug/kg-day and DPR potency factors, the risks were 7 x 10 -6
and 1.3 x 10 -5 for q 1 and q 1 *, respectively.
Combined Exposure
For workers exposed to DDVP acutely at work, at home, and in the diet, the MOSs were less than 10
(Table 25).
The MOSs for non-oncogenic effects from chronic exposure were 12 or less for all workers (Table 25).
The MOSs for non-oncogenic effects after lifetime exposure were 7 to 20 (Table 25).
The lifetime oncogenic risk for residents ranged from 2 x 10 -4 to 1 x 10 -3 .
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