Imiprothrin

Imiprothrin is an inducer of CYP1A2 and metallothionein 1a, exhibiting significant genotoxicity and cytotoxicity. In rat hepatocytes, it triggers detoxification responses by upregulating these genes. Imiprothrin induces chromosomal aberrations and micronucleus formation in rat bone marrow and causes DNA damage in liver cells. It leads to oxidative stress in rats, resulting in lipid peroxidation, excessive reactive oxygen species, and redox imbalance, subsequently impairing liver and kidney function and causing tissue damage. Imiprothrin inhibits weight gain in mice and, at high doses, significantly increases mortality in female mice. However, it shows no carcinogenic properties in rat studies, where aspartate aminotransferase and total protein are identified as sensitive toxicity biomarkers.

Imiprothrin (75-100 μg/mL) can induce chromosomal aberrations in Chinese hamster lung cells. It shows no mutagenicity towards Salmonella or E. coli cells in the Ames test, regardless of metabolic activation. Additionally, Imiprothrin does not cause gene mutations in Chinese hamster cells in in vitro gene mutation assays. However, in vitro conditions with S9 metabolic activation reveal that Imiprothrin can lead to chromosomal aberrations in Chinese hamster lung cells.

Imiprothrin, administered intraperitoneally at doses of 19-75 mg/kg daily for 5 days in male Wistar rats, results in dose-dependent subacute toxicity. This includes oxidative stress, liver and kidney dysfunction, genotoxicity, histopathological damage, and the upregulation of detoxification gene expression. In another study, when mice were given Imiprothrin orally at 7000 ppm for 78 weeks, there was a slight, non-significant increase in lung tumor incidence. This dosage surpassed the maximum tolerated dose (MTD) and caused significant systemic toxicity; however, no notable carcinogenic effects were seen at or below the MTD. Additionally, oral administration of Imiprothrin at 50-5000 ppm over 104 weeks in rats did not demonstrate carcinogenic activity, with only mild non-carcinogenic systemic toxicity observed at the highest tested dose of 5000 ppm.