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Description of key information

The test item is at least partially absorbed by all ways of exposure (oral, inhalation, dermal) and the main fraction is possibly excreted via feces.

Key value for chemical safety assessment

Additional information

The available data allow only for a qualitative assessment of the toxicokinetic behaviour of the test item.

 

The test item has surface-active properties: Its intended use is the reduction of surface tension. It has low water solubility (0.2 -0.5 g/L) and a log Pow of 8.2. The high log Pow and the lower water solubility suggest a possible passive absorption by diffusion through cell membranes including dermal absorption and a rather high bioaccumulation potential coupled with only limited excretion rates without preliminary metabolism/biotransformation. In the test for acute oral toxicity, the substance was administered once to rats at a dose level of 5000 mg/kg body weight. No mortalities occurred but various clinical signs were observed in the animals. No effects on the organs were recorded during the macroscopic examination at necropsy. In the test for acute dermal toxicity, the mixture was applied once to rats at a dose level of 2000 mg/kg body weight. No mortalities occurred but dermal irritation was observed in the animals and alopecia resulted in one animal. The macroscopic examination at necropsy revealed no effects on the organs. In the test tor acute toxicity by inhalation, the rats were exposed to a test item dose of 2.12 mg/L. One animal died and several clinical signs were recorded during exposure to the test item (while in the chamber), upon chamber removal and still several days thereafter. The exposure was followed by a transient body weight loss. The macroscopic examination at necropsy resulted in no findings. The skin and eye irritation studies were performed with rabbits. The test item was applied to them at amounts of 500 mg and 0.1 mL, respectively. For the skin sensitization study, guinea pigs were used. The substance was found to be irritanting to both skin and eyes but it is no skin sensitizer. The 5-days sub-acute oral toxicity study in rats resulted in no substance-related findings up to the highest dose' level of 1000 mg/kg body weight. The 14-days sub-acute inhalation toxicity study in rats resulted in several clinical findings (dose levels 0.036-0.307 mg/L). In the 28-days sub-acute inhalation toxicity study, the rats were exposed to the test item at three different dose levels (0.0037-0.038 mg/L). No mortalities were observed but reduced food consumption and reduced body weight gain was observed in all rnales treated with the highest dose. These findings did not resolve during the 14-days recovery period. Dose­ related levels of respiratory tract irritation were observed in all animals. The findings concerned the larynx (necrosis of ventral cartilage, epithelial hyperplasia and squamous metaplasia), the lungs (alveolar duet thickening) and the nasal turbinates (eosinophilic inclusions in olfactory epithelium). These changes resolved only partially during the recovery period. All other parameters remained unchanged (water consumption, haematology, biochemistry, organ weights and macro-pathology). The noted clinical signs were considered to be attributable to the method of dosing.

In a sub-acute toxicity study the test item was administered daily by oral gavage to Wistar rats at dose levels of 100, 300 and 1000 mg/kg bw/day for a period of 28 days. This study supported the assumption that the test item will be absorbed after oral exposure as reduced body weight development, minor changes in the hematology parameters, and changes in parameters of clinical biochemistry. Stomach and liver seems to be the target organs due to changed organ weights and/or macroscopic findings. Histopathological findings were additionally noted in the stomach.

The above-mentioned results strongly suggest that the substance is at least partially absorbed by all ways of exposure (oral, dermal, inhalation) and causes various clinical signs and effects of local toxicity (skin and eye irritation, respiratory tract irritation).

 

However, after oral exposure, the main fraction of the substance is possibly excreted via faeces. It is unclear whether the absence of micro- and/or macro-pathological findings in all organs not directly exposed to the test item is due to the rapid metabolism/biotransformation of the components of the substance leading to their detoxification and/or excretion.