Investigation of Genotoxic Mechanisms of Etofenprox: Cytotoxicity, Micronucleus and Comet Analyses

Abstract

Etofenprox is a synthetic pyrethroid pesticide widely used in agriculture, with significant ecotoxicological concern due to its potential for long-term persistence in the environment. This study aimed to evaluate the cytotoxic and genotoxic effects of etofenprox on Chinese hamster ovary (CHO) cells. Cytotoxicity was determined by measuring the cytokinesis-block proliferation index (CBPI) after exposure to various concentrations (1–800 µg/mL) of etofenprox. Genotoxicity was assessed using the micronucleus (MN) assay and alkaline comet assay. The results revealed significant reductions in CBPI, increases in MN frequency, and pronounced elevations in DNA damage parameters (tail length, % tail DNA, olive tail moment) at higher concentrations. These effects increased in a dose-dependent manner, particularly at concentrations ≥200 µg/mL, where the changes were statistically significant (p<0.05). The data indicate that at high doses, etofenprox may cause both clastogenic effects and DNA strand breaks. The findings suggest that, while the pesticide may pose a low risk at typical environmental exposure levels, high-dose exposure can induce adverse effects at cellular and genetic levels.

Keywords

• Etofenprox
• genotoxicity
• cytotoxicity
• micronucleus assay
• comet assay

Etofenprox’un Genotoksik Mekanizmalarının İncelenmesi: Sitotoksisite, Mikronükleus ve Komet Analizleri

Öz

Etofenprox, tarımda yaygın olarak kullanılan sentetik bir piretroit pestisittir ve çevrede uzun süre kalabilme potansiyeli nedeniyle ekotoksikolojik açıdan önem taşımaktadır. Bu çalışma, etofenprox’un Çin hamsteri ovaryum (CHO) hücrelerinde sitotoksik ve genotoksik etkilerini değerlendirmek amacıyla gerçekleştirilmiştir. Sitotoksisite, farklı konsantrasyonlarda (1–800 µg/mL) etofenprox uygulaması sonrası hücrelerde çekirdek bölünme indeksi (ÇBİ) ölçülerek belirlenmiştir. Genotoksisite değerlendirmesi ise mikronükleus (MN) testi ve alkali komet testi ile yapılmıştır. Bulgular, yüksek doz uygulamalarında ÇBİ’de anlamlı azalmalar, MN frekansında artışlar ve DNA hasar parametrelerinde (kuyruk uzunluğu, kuyruk DNA yüzdesi, olive kuyruk momenti) belirgin yükselişler olduğunu göstermiştir. Bu etkiler doza bağımlı olarak artmış ve özellikle ≥200 µg/mL konsantrasyonlarda istatistiksel olarak anlamlı bulunmuştur (p<0.05). Elde edilen veriler, etofenprox’un yüksek dozlarda hem klastojenik hem de DNA zincir hasarına neden olabileceğini ortaya koymaktadır. Çalışma, bu pestisitin çevresel maruziyet seviyelerinde düşük risk taşıyabileceğini, ancak yoğun temas koşullarında hücresel ve genetik düzeyde olumsuz etkiler oluşturabileceğini göstermektedir.

Anahtar Kelimeler

• Etofenprox
• genotoksisite
• sitotoksisite
• mikronükleus testi
• komet testi

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