Reaction mass of (R)-cyano(3-phenoxyphenyl)methyl rel-(1R,3R)-3-((1Z)-2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropanecarboxylate and (R)-cyano(3-phenoxyphenyl)methyl rel-(1S,3S)-3-((1Z)-2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropanecarboxylate

Repeated dose toxicity: oral

Administrative data

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

April 1981-June 1981

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

This study was conducted according to the principles and practices of Good Laboratory Practice. A Quality Assurance statement is included in the report. This was an investigative study therefore not required to comply with any current regulatory guideline.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1982

Report date:

1982

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

This 28-day oral toxicity study in the rat on cyhalothrin was conducted to investigate the reversibility of treatment related effects. This was an investigative study therefore not required to comply with any current regulatory guideline.

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Reaction mass of (R)-cyano(3-phenoxyphenyl)methyl rel-(1R,3R)-3-((1Z)-2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropanecarboxylate and (R)-cyano(3-phenoxyphenyl)methyl rel-(1S,3S)-3-((1Z)-2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropanecarboxylate

EC Number:

932-389-6

Molecular formula:

C23H19ClF3NO3

IUPAC Name:

Reaction mass of (R)-cyano(3-phenoxyphenyl)methyl rel-(1R,3R)-3-((1Z)-2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropanecarboxylate and (R)-cyano(3-phenoxyphenyl)methyl rel-(1S,3S)-3-((1Z)-2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethylcyclopropanecarboxylate

Test animals

Species:

rat

Results and discussion

Target system / organ toxicity

Critical effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

The study is considered to be reliable with restrictions. The results are sufficiently detailed and unambiguous as to be adequate for risk assessment, classification and labeling.

Executive summary:

In a subchronic toxicity study, 250 ppm cyhalothrin in diet was administered to a group of 32 male rats for 28 days. A similar group of rats received control diet. After this period eight rats per group were killed and examined. The remaining rats were fed control diet for periods of 7, 14 or 28 days after cessation of treatment, and a further eight rats per group were killed and examined at each of these time intervals.

Preliminary feeding studies(Faupel et al 1980, Moyes et al 1981) in rats have shown that cyhalothrin produced treatment related effects on bodyweight, small increases in liver weight, proliferation of smooth endoplasmic reticulum (SER) and elevated hepatic aminopyrine-N-demethylase (APDM) activity at a dietary level of 250 ppm cyhalothrin. Similar effects were seen on feeding this level of cyhalothrin to rats for 90 days, but the liver weights were unaffected(Lindsay et al 1981). Although cyhalothrin induced changes were seen in both sexes, male rats were more susceptible. The aim of this study was to determine whether treatment related liver changes were reversible, as an aid to establishing their significance.

A decrease in bodyweight gain was seen in the 250 ppm cyhalothrin group, which persisted during the 28 day recovery period.

Proliferation of the hepatic smooth endoplasmic reticulum and elevated hepatic aminopyrine-N-demethylase activity were also seen in the treatment group. These effects had reversed 7 days after the cessation of treatment with cyhalothrin and were considered to be physiological adaptive changes rather than a toxicological effect.

Administration of 250 ppm cyhalothrin in diet produced reversible and adaptive changes in the liver, characterised by SER proliferation and increased APDM activity. This level of cyhalothrin also produced adecrease in bodyweight gain which was still apparent 28 days after the cessation of treatment.