Article Effect of β -cyfluthrin (synthetic pyrethroid) on learning, muscular coordination and oxidative stress in Swiss albino mice Neelu Kanwar Rajawat 1 , Inderpal Soni 2 , Farah Syed 2 , Rajbala Verma 2 , PJ John 2 and Reena Mathur 2 Abstract The present study was planned to evaluate neurotoxic effects of β-cyfluthrin in female Swiss albino mice. Two doses of β-cyfluthrin, specifically, one-tenth of median lethal dose (LD 50 ) and one-twentieth of LD 50 , were selected for the study. Open-field behaviour, exploratory behaviour and emotional status were affected, and animals showed anxiety-like behaviour after β-cyfluthrin administration. Spatial learning was decreased using the Hebb–Wiliams maze. Acetylcholinesterase enzyme activity significantly decreased in the treated animals. The administration of β-cyfluthrin caused increased lipid peroxidation (malondialdehyde) and decreased superoxide dismutase, catalase and glutathione peroxidase activity in brain tissue. In conclusion, β-cyfluthrin caused neurotoxicity as well as oxidative damage in the brain of Swiss albino mice at the tested dose levels. Keywords β-Cyfluthrin, locomotory behaviour, neuromuscular coordination, learning, oxidative stress Received 9 July 2018; Revised 1 March 2019; Accepted 8 March 2019 Introduction Pesticides comprise a large group of substances that are of great importance in modern food production and for the control of pests and weeds. Use of these chemicals has improved our life in a variety of ways. However, some of these chemicals may adversely affect our environment, animals and plants, directly or indirectly, at even lower concentrations than those known to be lethal. Synthetic pyrethroids are a newer class of insecticides, safer than other pesticides. Clas- sically, pyrethroids have been divided into two types, type I and type II, based on chemical structure and the acute poisoning syndromes observed in non-target species at near-lethal dose levels (Soderlund et al., 2002; Vijverberg and van den Bercken, 1990). Type I pyrethroids are known to produce T-syndrome of poisoning characterized by tremors, while type II pyr- ethroids produce a Choreathetosis with salivation (CS)-syndrome characterized by increased pawing and burrowing behaviour followed by profuse saliva- tion, whole body tremors, and a ‘sinuous writhing’ motion known as choreoathetosis (Verschoyle and Aldridge, 1980). In the present work, β-cyfluthrin has been used, which is a type II synthetic pyrethroid found in a number of formulations in India and around the world. It is an active ingredient of many insecticide prod- ucts (Rajawat et al., 2014) used for a wide array of pests in agriculture, in and around the home and in food handling establishments (Mense et al., 2006). Its ISO-approved common name is 3-(2,2-dichloro-vinyl)-2,2-dimethyl- cyclopropane-carboxylic acid cyano-(4-fluoro-3-phe- noxy-phenyl)-methyl ester (FAO, 1999). Like all synthetic pyrethroids, β-cyfluthrin is a neurotoxicant. It causes hyperexcitation of the nervous system, 1 Department of Zoology, The IIS University, Jaipur, India 2 Environmental Toxicology Lab, Department of Zoology, University of Rajasthan, Jaipur, India Corresponding author: Inderpal Soni, Environmental Toxicology Lab, Department of Zoology, University of Rajasthan 302004, Jaipur, India. Email: inderpalsoni@gmail.com Toxicology and Industrial Health 2019, Vol. 35(5) 358–367  The Author(s) 2019 Article reuse guidelines: sagepub.com/journals-permissions DOI: 10.1177/0748233719840957 journals.sagepub.com/home/tih