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The test substance is a light yellow powder with a molecular weight of 351.49 g/mol. The log P o/w value is 7.25 and the solubility in water is < 1 µg/l (20°C, pH 6.3). The particle size was examined to be < 10 µm = 37.9 % and < 4 µm = 7.2% (MMD = 11.5 µm).

In an acute oral toxicity study, TIF: RAIf (SPF) rats were administered doses of up to 7750 mg/kg body weight per gavage (CIBA-Geigy study, Siss 6481, 1978). No mortalities occurred and the LD50 oral was set to be > 7750 mg/kg body weight. However, according to the physico-chemical properties (molecular weight, log P o/w) the test substance is expected to be absorbed through the gastrointestinal tract (ECHA R7c). This is supported by two independent subchronic studies conducted in beagle dogs (Inbifo, No. A 0176/049, 1970) and albino rats (TNO, No. R 2640, 1968). The test substance was administered via the diet in doses of 15 - 240 mg/kg body weight and 10 - 173 mg/kg body weight, respectively. In both studies significant food depression occurred and one dog starved. No further mortalities occurred. Both studies report liver effects induced by the test substance down to the lowest dose levels applied. Furthermore, effects on kidneys and discolouration of the urine were observed, indicating a systemic availability of the test substance. Based on the lipophilic properties of the test substance, the liver appears to be the main site of metabolism. The metabolites are assumed to be excreted predominantly via the renal pathway.

The dermal uptake of the test substance is unlikely due to its physico-chemical parameters. However, in a dermal repeated dose study conducted in albino rabbits (University of Miami, No. 69, 1977) with 140 mg/kg body weight, discolouration of the urine was observed. Indicating a systemic availability, it is not clear, whether the test substance was absorbed via the dermal route or the uptake was artificial because of inappropriate experimental design. Furthermore, the test substance did not exhibit any acute dermal toxicity (Geigy (U. K.) Ltd., 8/69/S. L., 1969), skin irritative / corrosive (CIBA-Geigy, No. 874135, 1987), eye irritative (CIBA-Geigy, No. 874134, 1987) or skin sensitisation properties (CIBA-Geigy, No. 874136, 1987), respectively.

Inhalative absorption of the test substance is likely due to the particle size and the physico-chemical parameters (poor water solubility and log P o/w). In contrast, an acute inhalative toxicity study (CIBA-Geigy, Siss 3502, 1973) did not reveal signs for bioavailability via the respiratory pathway. Tif. RAI rats were exposed using a nose-only system to a technically maximal achievable analytical substance concentration of 0.4 mg/l for 4 hours and did not show any clinical sign of toxic effects of the test substance.