Dose- and dosage-dependent spectrum of respiratory toxicity of cypermethrin in rabbits

Abstract

Pyrethroids are popular insecticides. Shortness of breath and dyspnea are key signs of exposure; however, their respiratory effects are rarely studied. This study investigated the combination and ratios of specific blood tests and lung lesions as respiratory effects of cypermethrin (CY) in rabbits. The effects of CY at various doses and times are the novelty of this study. Doses (50, 100, and 150 mg.kg^-1 body weight) of CY were injected intraperitoneally every week for up to 9 weeks in rabbits assigned into four equal groups. Data analysis revealed various respiratory signs, significantly (p ≤ 0.05) lower fibrinogen, higher neutrophils-lymphocytes (NL), LDH-lymphocytes (LL), and De-Ritis ratios (DR), and lesions in the lungs. The frequency and incidence of these effects were dose and dosage dependent. The CY leads to pulmonary signs and allergic effects. Lung injury increases cell-free heme in plasma, causing pulmonary edema with hemolysis. Emphysema and fibrosis followed the migration of basophils and mononuclear cells to the lungs. This study inferred that CY exposure caused lower fibrinogen, higher NL, LL, and DR ratios, and pulmonary lesions, which forecast poor immunity, especially increased risk for cardiac and lung diseases.

Keywords:

• Cypermethrin
• toxicity
• ptyalism
• enzymes
• pathology

Author contributions

AK conceived and designed the project and study. LA executed the experiment, evaluated the clinical signs and samples, and analyzed the data under supervision of AK. The manuscript was drafted by LA, RH, STG, AUR, MRK, SI and XXD. AK, LA and XXD interpreted the data and critically revised the manuscript for important intellectual contents. All authors discussed the results and approved the final version.

Disclaimer

The views and opinions expressed in this article are those of the authors and do not reflect the official position or policy of the affiliation.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The authors disclosed receipt of this support for the research: MLA 0543318, HEC Pakistan.