Pesticide residues in food — 2007: Toxicological ... - ipcs inchem

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finding. Histopathology revealed that the incidence of a testicular atrophy was higher than that among
the controls, achieving statistical significance at 500 ppm (Table 12). Liver weights and histological
findings were unaffected by treatment.
The NOAEL was 150 ppm, equal to 20 mg/kg bw per day, on the basis of the statistically
significant increase in testicular atrophy at 500 ppm. This study did not claim GLP compliance (Arai
et al., 1980b).
An additional 6-month study was conducted to further investigate the testicular atrophy
reported by Arai et al. (1980b). Groups of 20 male Alpk/AP albino mice received diets containing
procymidone (purity, 99.8%) at a concentration of 0, 10, 30, 100 or 300 ppm. Mice were checked
daily and a detailed clinical examination was given weekly. Body weight was monitored weekly and
food consumption was recorded weekly for the first 12 weeks and then for 7 days every 4 weeks
for the remainder of the study. At termination, mice were given a full postmortem, the testes and
epididymides from mice in all groups were weighed and examined by histopathology. Mean achieved
intakes were 0, 1.1, 3.6, 11 and 37 mg/kg bw per day.
One mouse at the lowest dose died. No treatment-related clinical signs or deaths were reported.
Body-weight gain, food consumption and food use were not influenced by treatment. After 26 weeks,
organ-weight analysis and histopathology of testes and epididymides revealed no evidence of a treatment-related
effect (Table 13). The NOAEL was 300 ppm, equal to 37 mg/kg bw per day, on the basis
of the absence of dose-related effects. The study was checked by a quality assurance unit (Kinsey
et al., 1985).
Rats
Groups of 12 male and 12 female Sprague-Dawley rats were fed diets containing procymidone
(purity, 98.7%) at a concentration of 0, 150, 500 or 1500 ppm for 6 months. Additional groups of 15
males and 15 females were fed diets containing procymidone at 0 or 1500 ppm for 9 months, or 0 or
1500 ppm for 6 months and then placed on a control diet for another 3 months. Rats were observed
Table 12. Leukocyte and testicular findings in mice (n = 20) fed diets containing procymidone for
6 months
Finding
Dietary concentration (ppm)
0 50 150 500
Males Females Males Females Males Females Males Females
Intake (mg/kg bw per day) 0 0 6.5 7.3 20 24 72 83
Leukocytes (10 2 /mm 3 ) 48 41 47 46 39* 41 34* 37
Testicular atrophy (all grades; 2 — 5
(p = 0.2)
— 6
(p = 0.1)
— 10*
(p = 0.01)
—
From Arai et al. (1980b)
* p < 0.05.
Table 13. Testes and epididymides weights in mice fed diets containing procymidone for 6 months
Organ weight
Dietary concentration (ppm)
0 10 30 100 300
Testes (mg) 213 240 225 257* 233
Epididymis (mg) 104 107 105 115 103
From Kinsey et al. (1985) * p