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

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(e)
Dermal sensitization
The dermal sensitization potential of dimethomorph (purity, 98.0%) was investigated in male
Crl (HA)BR guinea-pigs via the maximization test of Magnusson & Kligman. In two pre-test studies,
four males received 0.1 ml of dimethomorph intradermally at a concentration of 1%, 5%, 10%,
15%, and 25% in mineral oil and another four males received dimethomorph topically at a concentration
of 1%, 5%, 10%, and 25% in petrolatum occluded for 24 h by patches. All guinea-pigs in both
groups received all doses and were evaluated for skin irritation 24 h and 48 h after application. In the
group treated by intradermal injection, all doses induced dose-dependent skin irritations that were
moderate-intense at 5%. In the group treated by topical application, no irritation was observed at
any dose. For the main study, the concentrations of 5% for intradermal injection and 25% for topical
application were selected.
Twenty males were induced intradermally with 5% dimethomorph in mineral oil and Freund
complete adjuvant and then on day 9 topically with 25% dimethomorph in petrolatum. On day 23,
the guinea-pigs were challenged by topical application of 25% dimethomorph in petrolatum. The
negative-control group consisted of 20 males. The study complied with GLP.
No skin irritation was recorded in any of the challenged or control guinea-pigs and the Meeting
concluded that dimethomorph has no skin sensitization potential (Glaza, 1997)
Table 11. Results of studies of acute toxicity with dimethomorph
Isomer Species Strain Sex Route LD 50
(mg/kg bw) LC 50
(mg/l)
Purity (%)
Reference
E : Z Rat CD Male Oral 4300 — NS Kynoch (1985)
E : Z CD Female Oral 3500 — NS Kynoch (1985)
Z Wistar Males
and
females
Oral > 5000 — NS Heusener &
Jacobs (1987a)
E Wistar Male Oral 4715 — NS Heusener &
Jacobs (1987b)
E Wistar Female Oral 4754 — NS Heusener &
Jacobs (1987b)
E : Z Wistar Males
and
females
E : Z Fischer Males
and
females
E : Z Wistar Males
and
females
E : Z Rabbit NZW Males
and
females
E : Z Rabbit NZW Males
and
females
Dermal > 5000 — 98.7 Heusener &
Eberstein (1985)
Dermal > 2000 — 98.5 Gardner (1989)
Inhalation — > 4.24 98.7 Jackson & Hardy
(1986)
Dermal Not irritating — 98.5 Gardner (1989)
Ocular Not irritating — 98.5 Gardner (1989)
E : Z Guinea-pig Crl (HA)BR Male Dermal No sensitization — 98.0 Glaza (1997)
NS, not stated; NZW, New Zealand White.
DIMETHOMORPH 273–315 JMPR 2007