2-Thiophenecarboxylic acid, 5-chloro-

Endpoint summary

Link to relevant study record(s)

Reference

Endpoint:

basic toxicokinetics, other

Remarks:

expert judgement

Type of information:

other: expert judgement

Adequacy of study:

other information

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Objective of study:

absorption

Qualifier:

no guideline followed

Principles of method if other than guideline:

Toxicokinetic statement based on available physico-chemical and toxicological data according to REACH Guidance R.7

GLP compliance:

no

Details on absorption:

The toxicokinetics of 5-Chlorthiophen-2-carbonsäure are based on the studies performed within the process of registration of a new chemical under the Chemicals Act, Base Set. Experimental toxicokinetic studies have not been performed. The physico-chemical characteristics of 5-Chlorthiophen-2-carbonsäure (readily soluble in water (1.01 g/L at 20 °C), log POW of 1.95) and the molecular mass of 162.6 g/mol are in a range suggestive of absorption from the gastro-intestinal tract subsequent to oral ingestion. This assumption is confirmed by the data on acute and subacute oral toxicity. The findings of the subacute oral toxicity study indicate systemic availability of the test substance. The NOAEL of this study was established at 50 mg/kg body weight/day in male and female animals. The onset of growth retardation early during the study (after the first treatment with the test substance) suggests rapid absorption from the GI tract.
Water solubility, n-octanol/water partition coefficient and molecular weight of 5-Chlorthiophen-2-carbonsäure are in ranges which favor dermal absorption. Therefore, absorption through the skin may be assumed a route of exposure. However, in a study assessing the acute dermal toxicity of 5-Chlorthiophen-2-carbonsäure to rats a dose of 2000 mg/kg body weight was tolerated by male and female animals without mortalities, clinical signs, effects on body weight development and gross pathological findings. In acute skin and eye irritation studies in rabbits no systemic intolerance reactions have been observed and no sensitizing effect has been identified in the Local Lymph Node Assay. Based on the results of the in vitro genotoxicity tests it is concluded that DNA-reactive metabolites of 5-Chlorthiophen-2-carbonsäure will most probably not be generated in mammals in the course of hepatic biotransformation.

Conclusions:

The test item is considered to be readily intestinally absorbed. Dermal absorption seems to be reduced in comparison to oral absorption based on the results from the acute dermal toxicity and skin and eye irritation studies.

Description of key information

The test item is considered to be readily intestinally absorbed. Dermal absorption seems to be reduced in comparison to oral absorption based on the results from the acute dermal toxicity and skin and eye irritation studies.

Key value for chemical safety assessment

Bioaccumulation potential:

no bioaccumulation potential

Absorption rate - oral (%):

50

Absorption rate - dermal (%):

10

Absorption rate - inhalation (%):

100

Additional information

The toxicokinetics of 5-Chlorthiophen-2-carbonsäure are based on the studies performed within the process of registration of a new chemical under the Chemicals Act, Base Set. Experimental toxicokinetic studies have not been performed. The physico-chemical characteristics of 5-Chlorthiophen-2-carbonsäure (readily soluble in water (1.01 g/L at 20 °C), log POW of 1.95) and the molecular mass of 162.6 g/mol are in a range suggestive of absorption from the gastro-intestinal tract subsequent to oral ingestion. This assumption is confirmed by the data on acute and subacute oral toxicity. The findings of the subacute oral toxicity study indicate systemic availability of the test substance. The NOAEL of this study was established at 50 mg/kg body weight/day in male and female animals. The onset of growth retardation early during the study (after the first treatment with the test substance) suggests rapid absorption from the GI tract.
Water solubility, n-octanol/water partition coefficient and molecular weight of 5-Chlorthiophen-2-carbonsäure are in ranges which favor dermal absorption. Therefore, absorption through the skin may be assumed a route of exposure. However, in a study assessing the acute dermal toxicity of 5-Chlorthiophen-2-carbonsäure to rats a dose of 2000 mg/kg body weight was tolerated by male and female animals without mortalities, clinical signs, effects on body weight development and gross pathological findings. In acute skin and eye irritation studies in rabbits no systemic intolerance reactions have been observed and no sensitizing effect has been identified in the Local Lymph Node Assay. Based on the results of the in vitro genotoxicity tests it is concluded that DNA-reactive metabolites of 5-Chlorthiophen-2-carbonsäure will most probably not be generated in mammals in the course of hepatic biotransformation.