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

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Table 1. Metabolism of atrazine by hepatocytes from different species in vitro
Species
Metabolite
Sprague-
Rhesus
F-344 rat Mouse
Dawley rat
monkey
Goat Guinea-pig Human
Atrazine (%) ND ND ND 2 60 4 19
DIA (%) 14 12 3 25 18 30 18
DEA (%) 5 6 6 10 20 32 50
DACT (%) 50 54 60 50 9% 10 < 5
Ratio of DEA to DIA 1 : 3 1 : 2 2 : 1 1 : 2.5 1 : 1 1 : 1 3 : 1
Conjugated metabolites
(%)
34 29 30 9 < 1 25 11
From Thede (1988)
DACT, diaminochlorotriazine; DEA, deethyl-atrazine; DIA, deisopropyl-atrazine; ND, not detected.
In a study of acute oral toxicity conducted in compliance with GLP and US EPA test guidelines,
groups of five male and five female HSD:(SD) rats received atrazine as a single dose at 4000–
5500 (males) or 2000–5500 (females) mg/kg bw suspended in 2% carboxymethyl cellulose. Clinical
symptoms included hypoactivity, ataxia, emaciation, lacrimation, nasal discharge, piloerection,
polyuria and salivation. The surviving rats recovered within 3–6 days. No organ-specific lesions were
discernible on macroscopic examination of the animals. Discoloration of the gastrointestinal tract in
the rat may be related to local irritation. The male, female and combined oral LD 50
and the 95% confidence
limits (CL) were 3520 mg/kg bw (2290–5400), 3000 mg/kg bw (2090–4300) and 3090 mg/
kg bw (2170–4420), respectively (Kuhn, 1991a).
In a study of acute dermal toxicity, groups of five male and five female Tif:RAIf rats received
atrazine as a single application at a dose of 2150 or 3170 mg/kg bw suspended in 2% carboxymethyl cellulose
on the shaved back skin. No mortality occurred during the 14-day observation period. There were
no treatment-related clinical signs or gross changes in the organs. The dermal LD 50
was > 3100 mg/kg
bw in males and females (Sachsse & Bathe, 1976).
In a study of acute dermal toxicity conducted in compliance with GLP and OECD test guidelines,
one group of five male and five female Tif:RAIf rats received atrazine as a single application at
a dose of 2000 mg/kg bw moistened with 0.5% carboxymethyl cellulose on the shaved skin for 24 h.
No mortality occurred. Clinical symptoms including piloerection and hunched body position were
seen on the first 5 days of application. No organ-specific lesions were discernible on macroscopic
examination of the animals. The dermal LD 50
was > 2000 mg/kg bw in males and females (Hartmann,
1993).
In a study of acute toxicity after exposure by inhalation that was conducted in compliance
with GLP and OECD test guidelines, one group of five male and five female Tif:RAIf rats was
exposed to atrazine at an average air concentration of 5148 mg/m 3 for 4 h. No mortality occurred.
Rats showed piloerection, hunched posture, dyspnea, and reduced locomotor activity. All animals
recovered within 5 days. No organ abnormalities were recorded. The median lethal concentration
(LC 50
) was > 5148 mg/m³ (5.15 mg/l) (Hartmann, 1989).
In a study of acute toxicity after exposure by inhalation that was conducted in compliance with
GLP and US EPA test guidelines, one group of five male and five female Sprague-Dawley rats was
ATRAZINE 37–138 JMPR 2007