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

Öz

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.

Anahtar Kelimeler

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

Destekleyen Kurum

This study was supported by the Uludağ University Scientific Research Projects Unit within the scope of the project titled “Investigation of the Genotoxic Effects of Etofenprox in Chinese Hamster Ovary Cells Using Micronucleus and Comet Assays” (Project No: HDP(F)-2012/20).

Etik Beyan

This study was derived from the author’s Master’s thesis titled “Etofenprox'un Genotoksik Etkilerinin Çin Hamsteri Ovaryum Hücrelerinde Mikronükleus ve Komet Testleri Kullanılarak Araştırılması” (Uludağ University, 2013). The thesis is registered in the National Thesis Center of the Council of Higher Education (YÖK) and has not been previously published in any academic journal. All procedures were carried out in accordance with international research, publication ethics, and citation principles. No fabrication or falsification of data occurred during the study, and all ethical responsibilities rest solely with the author.

Teşekkür

The author expresses sincere gratitude to Prof. Dr. Tolga Çavaş for providing the opportunity to conduct this study at the Department of Biology, Faculty of Science, Uludağ University, and to all members of the genotoxicity laboratory for their valuable assistance. The author also thanks the anonymous reviewers for their constructive comments and suggestions.

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

Destekleyen Kurum

Bu çalışma, Uludağ Üniversitesi Bilimsel Araştırma Projeleri Birimi tarafından “Etofenprox'un Genotoksik Etkilerinin Çin Hamsteri Ovaryum Hücrelerinde Mikronükleus ve Komet Testleri Kullanılarak Araştırılması” başlıklı proje (Proje No: HDP(F)-2012/20) kapsamında desteklenmiştir.

Etik Beyan

Bu çalışma, yazarın “Etofenprox'un Genotoksik Etkilerinin Çin Hamsteri Ovaryum Hücrelerinde Mikronükleus ve Komet Testleri Kullanılarak Araştırılması” başlıklı Yüksek Lisans tezinden türetilmiştir (Uludağ Üniversitesi, 2013). Tez, Yükseköğretim Kurulu (YÖK) Ulusal Tez Merkezi'nde kayıtlıdır ve daha önce herhangi bir akademik dergide yayımlanmamıştır. Tüm işlemler uluslararası araştırma, yayın etiği ve atıf ilkelerine uygun olarak gerçekleştirilmiştir. Çalışma sırasında hiçbir veri uydurma veya tahrifatına başvurulmamış olup, tüm etik sorumluluk yalnızca yazara aittir.

Teşekkür

Bu çalışmanın Uludağ Üniversitesi Fen Fakültesi Biyoloji Bölümünde gerçekleştirilmesine imkân sağlayan Prof. Dr. Tolga ÇAVAŞ’a, katkılarından dolayı tüm genotoksisite laboratuvarı çalışanlarına ayrıca öneri ve katkılarından dolayı hakemlere teşekkür ederim.

Kaynakça

1. Ahamad, A., & Kumar, J. (2023). Pyrethroid pesticides: An overview on classification, toxicological assessment and monitoring. Journal of Hazardous Materials Advances, 10, 100284. https://doi.org/10.1016/j.hazadv.2023.100284
2. Chu, Y., You, F., Wassick, J. M., & Agarwal, A. (2015). Integrated planning and scheduling under production uncertainties: Bi-level model formulation and hybrid solution method. Computers and Chemical Engineering, 72, 255–272. https://doi.org/10.1016/j.compchemeng.2014.02.023
3. Hojo, Y., Shiraki, A., Tsuchiya, T., Shimamoto, K., Ishii, Y., Suzuki, K., Shibutani, M., & Mitsumori, K. (2012). Liver tumor promoting effect of etofenprox in rats and its possible mechanism of action. Journal of Toxicological Sciences, 37(2), 297–306. https://doi.org/10.2131/jts.37.297
4. Malhat, F., Abdallah, H., & Nasr, I. (2012). Estimation of etofenprox residues in tomato fruits by QuEChERS methodology and HPLC–DAD. Bulletin of Environmental Contamination and Toxicology, 88, 891–893. https://doi.org/10.1007/s00128-012-0627-6
5. Hayashi, K., Nakae, A., Fukushima, Y., Sakamoto, K., Furuichi, T., Kitahara, K., Miyazaki, Y., Ikenoue, C., & Toda, T. (2010). Contamination of rice by etofenprox, diethyl phthalate and alkylphenols: effects on first delivery and sperm count in mice. Journal of Toxicological Sciences, 35(1), 49–55.
6. International Programme on Chemical Safety (IPCS). (1993). Bifenthrin. In Pesticide Residues in Food. Evaluations 1992. Part II – Toxicology. Joint FAO/WHO Meeting on Pesticide Residues (JMPR). Geneva: World Health Organization (WHO/PCS 93.34), pp. 79–102.
7. International Programme on Chemical Safety (IPCS). (1994). Etofenprox. In Pesticide Residues in Food. Evaluations 1993. Part II – Toxicology. Joint FAO/WHO Meeting on Pesticide Residues (JMPR). Geneva: World Health Organization (WHO/PCS 94.4), pp. 215–232.
8. International Programme on Chemical Safety (IPCS). (1996). Cypermethrin and λ-Cypermethrin. In Toxicological Evaluation of Certain Veterinary Drug Residues in Food. Prepared by the Forty-seventh Meeting of the Joint FAO/WHO Expert Committee on Food Additives (JECFA). Geneva: World Health Organization (WHO Food Additives Series No. 38), pp. 133–170.

9. International Programme on Chemical Safety (IPCS). (1997). λ-Cypermethrin. Geneva: World Health Organization (Environmental Health Criteria No. 142).
10. International Programme on Chemical Safety (IPCS). (2001). Deltamethrin. In Pesticide Residues in Food. Evaluations 2000. Part II – Toxicological. Joint FAO/WHO Meeting on Pesticide Residues (JMPR). Geneva: World Health Organization (WHO/PCS 01.3), pp. 79–110.
11. World Health Organization (WHO). (2005). Safety of Pyrethroids for Public Health Use. Geneva: WHO/CDS/WHOPES/GCDPP/2005.10.
12. Environmental Protection Agency (EPA). (1985). Guidelines for the Registration and Control of Pesticides. EPA, 29 pp.
13. United Nations Environment Programme (UNEP). (2007). Stockholm Convention on Persistent Organic Pollutants Persistent Organic Pollutants Review Committee Third Meeting, Geneva, 19–23 November 2007. UNEP/POPS/POPRC.3/12.
14. Bootman, J., & May, K. (1985). MTI-500 α-CO: Assessment of its Mutagenic Potential in Amino-Acid Auxotrophs of Salmonella typhimurium and Escherichia coli. Life Science Research Limited, Eye, Suffolk, England. LSR Report No. 85/MT0020/433.
15. Foster, D. E., & Wintersteen, W. K. (1986). W.K. Insectic Acaric Tests. Stalk Borer Control, 11, 230–231.
16. Seeberg, A. H. (1985). Unscheduled DNA synthesis in human cells, cell line: HeLa S3, test substance MTI-500. Life Science Research Roma Toxicology Centre, Italy. Report No. 162003-M-05785.
17. Demir, E., Kocağoğlu, S., & Kaya, B. (2008). Genotoxicity testing of four benzyl derivatives in the Drosophila wing spot test. Food and Chemical Toxicology, 46(3), 1034–1041.