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

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to intact skin; and that no reading was made at 48 h after application. However, the study is adequate
for the purpose intended. Very slight erythema was recorded on abraded skin of three animals and,
therefore, atrazine is classified as a mild skin irritant under EPA guidelines but is not an irritant under
OECD or EC criteria (Ullmann, 1976b).
(c)
Ocular irritation
In a study on eye irritation potential, atrazine powder (0.1 g) was applied into the left eyes of
three male and three female Himalayan rabbits, and after 30 s was rinsed out from three of these eyes.
The eyes were closely examined for reaction at intervals after application. The study deviates from
present OECD test guideline in that no recording was performed at 1 h. In view of the results, this
does not detract from the acceptability of the study. Atrazine caused no reaction to the eye at 24, 48
or 72 h, and therefore is non-irritant to the eye (Ullmann, 1976a).
(d)
Dermal sensitization
In a study on skin sensitization potential that was conducted in compliance with GLP and
OECD test guidelines (optimization test), 10 male and 10 female Pirbright White (Tif:DHP) guineapigs
received a total of 10 intradermal injections (each of 0.1 ml of 0.1% atrazine in 20% ethanol
and 80% physiological saline) during the induction period, while the control group (10 males and 10
females) received the vehicle only. Two weeks later, a challenge dose of 0.1 ml of 0.1% atrazine in
a mixture of 20% ethanol and 80% physiological saline was injected intradermally. Ten days later, a
sub-irritant level dose of 30% atrazine in vaseline was applied on the skin under occlusive patches for
24 h. Twenty-four and 48 h after removal of the patches, 10 out of 19 animals showed skin reactions
indicating sensitization potential in the test system (Maurer, 1983).
In a study on skin sensitization potential that was conducted in compliance with GLP and OECD
test guidelines (Magnusson & Kligman test), 10 male and 10 female Pirbright White (Tif:DHP)
guinea-pigs received three pairs of intradermal injections (adjuvant/saline 1 : 1, atrazine in oleum
arachidis 1% mixture, and atrazine in adjuvant/saline mixture 1%). One week later, 0.4 g atrazine
incorporated in vaseline (30%) was applied epidermally to the neck of the animals for 48 h. After a
2-week rest period (week 3 and 4) the guinea-pigs were challenged by application of 0.2 g of atrazine
at a concentration of 30% incorporated in vaseline for 24 h. Twenty-four and 48 h after removal of
the patches, 65% and 70% of the guinea-pigs showed skin reactions indicating sensitization potential
in the test system (Schoch, 1985).
In a study on skin sensitization potential, repeated-insult patch tests were conducted on 50
(otherwise undescribed) humans given 0.5 ml of a 0.5% suspension of atrazine 80W formulation
in water; the composition of the formulation was not given. Subjects received 15 consecutive 24-h,
alternate-day treatments followed by a 14-day rest period before a challenge dose. None of the subjects
reacted to any application or to the challenge. The tested spray dilution of atrazine did not
appear to be sensitizing to humans (Shelanski & Gittes, 1965).
2.2 Short-term studies of toxicity
Rats
In a study of oral toxicity, groups of 10 male and 10 female Tif:RAIf (Sprague-Dawley derived)
rats were fed diets containing atrazine (purity, 97.1%) at a concentration of 10, 50 or 500 ppm, equal
to 0, 0.6, 3.3 and 34.0 mg/kg bw per day in males and 0, 0.66, 3.35 and 35.3 mg/kg bw per day in
females, for 13 weeks. An additional 10 males and 10 females were allocated to the groups at the
ATRAZINE 37–138 JMPR 2007