Pyrethroid based pesticides – chemical and biological aspects

Abstract

Human and animal welfare primarily depends on the availability of food and surrounding environment. Over a century and half, the quest to identify agents that can enhance food production and protection from vector borne diseases resulted in the identification and use of a variety of pesticides, of which the pyrethroid based ones emerged as the best choice. Pesticides while improved the quality of life, on the other hand caused enormous health risks. Because of their percolation into drinking water and food chain and usage in domestic settings, humans unintentionally get exposed to the pesticides on a daily basis. The health hazards of almost all known pesticides at a variety of doses and exposure times are reported. This review provides a comprehensive summation on the historical, epidemiological, chemical and biological (physiological, biochemical and molecular) aspects of pyrethroid based insecticides. An overview of the available knowledge suggests that the synthetic pyrethroids vary in their chemical and toxic nature and pose health hazards that range from simple nausea to cancers. Despite large number of reports, studies that focused on identifying the health hazards using doses that are equivalent or relevant to human exposure are lacking. It is high time such studies are conducted to provide concrete evidence on the hazards of consuming pesticide contaminated food. Policy decisions to decrease the residual levels of pesticides in agricultural products and also to encourage organic farming is suggested.

Keywords:

• Pesticides
• pyrethroids
• allethrin
• cypermethrin
• permethrin
• fenvalerate
• deltamethrin
• λ-cyhalothrin
• neurotoxicity
• reproductive toxicity
• oxidative stress
• apoptosis
• epigenetics
• carcinogenicity

Acknowledgements

The authors thank Prof. Dr. Roger McClellan, Editor, Critical Reviews in Toxicology for his comments and guidance that helped us to learn many aspects of preparing a structured review article. His inputs improved the quality of the revised manuscript to a significant extent. The quality of the review article was also improved by applying the comments of the reviewers (anonymous to the authors) selected by the editor. We thank the reviewers and the editor for their patience and guidance. The review article was evaluated by two experts: Prof. Senthilkumaran Balasubramanian (SB), Department of Animal Biology, University of Hyderabad, Hyderabad, India and Prof. Vijay Kumar Kutala (VKK), Department of Pharmacology, Nizam’s Institute of Medical Sciences, Hyderabad, India. Prof. SB is my colleague and an accomplished professor and has expertise in aquatic toxicology. He serves as an associate editor for the journals Gene and PLoS ONE. Prof. VKK served as evaluator on the doctoral work progress of the first author (ARR) of this review. Prof. VKK is an expert in pharmacology, meta analyses, gene polymorphisms, biochemical and molecular aspects of free radical biology and cancer. He serves as an associate editor for the journal Gene, we thank the evaluators for their valuable input. We thank the facilities extended by UGC-SAP, UGC-CAS, DBT-CREBB, DST-PURSE, UGC-UPE-II and FIST programs at School of Life Sciences, University of Hyderabad. ARR received the junior and senior research fellowship from Department of Biotechnology, Government of India. The Directorate of Plant Protection, Quarantine (DPPQ), an institution funded by Government of India provided information on the quantum of pesticides used in India. The statistics are available at DPPQ webpage and are for public use. The authors have used this information and the authors thank DPPQ in this regard.

Declaration of interest

The authors declare no conflicts of interest. The authors are not affiliated with Directorate of Plant Protection, Quarantine (DPPQ) and none of the employees of this institution were contacted to prepare this review and thus are not contributors of this review. All the statements made in this review are the opinions of the authors as understood from the available literature. The evaluators (Prof. Senthilkumaran Balasubramanian and Prof. Vijay Kumar Kutala) provided inputs to improve the overall presentation and thus did not contribute to the actual preparation and presentation of the manuscript and hence they were not included as authors. The evaluators are aware of this agreement.

Supplemental material

Supplemental material for this article is available online here.