Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 235-557-0 | CAS number: 12286-65-6
There are no studies available in which the toxicokinetic properties of the test substance were investigated. Based on the large molecular size, the absence of adverse findings in toxicity studies at the test item and structural analogues, and the presence of functional groups for metabolism, a potential for bioaccumulation is unlikely.
There are no studies available in which the toxicokinetic properties of the test substance were investigated. Based on the large molecular size, the absence of adverse findings in toxicity studies at the test item and structural analogues, and the presence of functional groups for metabolism, a potential for bioaccumulation is unlikely. Further details for this assessments are given below.
The test substance (molecular weight of 848.9 Da) is a yellow powder those water solubility (deionised water) is 18 mg/l. The log Pow is < 1.6 (calc.) and the melting point is above 315 °C. Examination of the particle size distribution revealed that most of the substance particles are smaller than 4 µm. In regard to the molecular structure of the substance hydrolysis appears to be unlikely.
In an acute oral and dermal toxicity study, rats were administered to the test substance or an structural analogue. No mortalities or clinical signs of toxicity were observed at dose levels of 10.000 and 2000 mg/kg bw, respectively, indicating primarily a very low level of oral and dermal toxicity. The NOAEL in male and female rats in a subacute oral repeated dose study on an analogue substance (OECD guideline 422) is 1110 mg/kg bw. Due to the high molecular weight (> 500 g/mol) gastrointestinal absorption is very limited. As it does not bear resemblance to fatty acids, uptake via micelles with bile acids is unlikely. It is presumed that the complex dissolves in an acidic environment (pH < 3; e.g. stomach) into the cation (calcium) and the organic compound. The divalent metal ion Ca2+is of low toxicity so that the hazard profile is determined by the organic anion. At environmentally relevant pH values (pH 4 to pH 9) the substances are not expected to hydrolyze.
Skin penetration can be excluded based on model calculation (Fitzpatrick, et al., 2004).
The test substance decomposes at temperatures above 300 °C. This indicates that absorption of the substance via vapour inhalation is not relevant.
Single oral application of the analogue substance to male and female rats did not provoke any effect up to 14 days post observation period. Oral administration of the analogue to Wistar rats at doses of 110, 330 and 1110 mg/kg/day, for 28 days, resulted in no test item-related effects and no differences in food consumption or body weight development. The hematology, clinical biochemistry and urinalysis parameters did not show test item-related differences when compared with those of the controls. Organ weights of test item-treated animals were unaffected. Macroscopically yellow discoloration of the content of the digestive tract in numerous animals was observed. In single treated animals and single organs of the digestive tract these yellow pigments could also be observed histopathologically. Beside the discoloration no signs of toxicity in the respective tissues were noted. Based on the results of this study, 1110 mg/kg/day was considered to be the no observed- adverse-effect-level (NOAEL).
No indication of uptake or chemical reactivity was observed in any study, including acute studies, irritation, sensitization and genotoxicity in vitro as well as the above described subacute study.
In case of uptake, a potential metabolism might involve hydroxylation of keto- and methyl-groups. Furthermore, cleavage of the azobond by gastrointestinal bacterial enzymes may lead to formation of aromatic amines. Reduction of the nitro-group by bacterial or hepatic enzymes to hydroxylamin and aromatic amines is also possible. Though, corresponding clinical signs, e.g. met-Hb formation or anemia, were not observed. The test substance is not expected to accumulate in the body.
As mentioned above, the substance is expected to be excreted unchanged via the feces. In case of gastrointestinal uptake and metabolism through hydroxylation, azobond reduction and phase-II substitution of chlorine (at structural analogues) it is expected that the test substance might be excreted predominantly via the urine. Overall, the test substance is not expected to accumulate in the body.
Fitzpatrick, D., et al. (2004). "Modelling skin permeability in risk assessment-the future." Chemosphere 55 (10): 1309-14.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
Welcome to the ECHA website. This site is not fully supported in Internet Explorer 7 (and earlier versions). Please upgrade your Internet Explorer to a newer version.
Close Do not show this message again