Synthetic pyrethroids (Type II) and freshwater fish culture: Perils and mitigations

Abstract

As a new class of agricultural insecticides, synthetic pyrethroids are widely used to control insect pests. Synthetic pyrethroids have been shown to enter the aquatic environment from agricultural runoff or drift from aerial and ground-based spraying applications posing threat to fishes which are less tolerant to pesticides through direct exposure. These insecticides interfere with the sodium channel of the nervous system resulting in prolonged sodium tail current. Widespread application of these chemicals has warranted the attention of the ecologist to understand the impact of these chemicals on the aquatic environment. In this perspective, an updated account of toxicological evaluation of three type II synthetic pyrethroids, viz. deltamethrin, cypermethrin and fenvalerate in terms of their physico-chemical, metabolic, hematological, histological, behavioral and reproductive aspects with respect to the fishes has been presented which may be useful for policy makers, academics, environmental scientists and agricultural professionals needing ready access to this information. The aim of the present synoptic literature appraisal was to summarize the main effect of current use, type II synthetic pyrethroids (deltamethrin, cypermethrin and fenvalerate) on aquatic environment due to their persistence and accumulation. This article will focus on non-target organisms in inland fresh water environment with special reference to fin fishes and will critically evaluate the toxicity of these pyrethroids in terms of growth inhibition, metabolic disorders, neurotoxicity, reproductive failure, enzymatic dysfunction, haematological alterations, and tissue damages. The rationalized information in this milieu may be useful in ecological risk evaluation and human health management as fish serves as an important bio-indicator for aquatic systems health.

Prolonged mosquitocidal activity of Siparuna guianensis essential oil encapsulated in chitosan nanoparticles

“…It was possible to observe that, even in a concentration 2.3 times higher than the concentration suggested as limit in the acute toxicity tests on fish, the mortality was less than 15% (S1A Fig). This toxicity is lower than that observed with pyrethroids for fish and other aquatic organisms, for example [87].…”

Toxicological Responses of African Mud Catfish (Clarias gariepinus, Burchell, 1822) Fingerlings Exposed to Culture Water Contaminated with Different Concentrations of Cypermethrin

“…Water covers about 70% of the earth, and happens to be the most essential natural resources [15]. Despite this awareness of the essentiality of water, humans have ignored its importance by polluting it [16]. The advancement in industrialization has coincided with the problem of aquatic pollution.…”

Adverse Effects of Cypermethrin on the Chick (Galus domesticus) Development are Reversed by Co-Treatment with Vitamin E and Olive Oil

“…However, the developing embryos of the non-target animals are much more sensitive to toxic insults as compared to the adults' due to their partial metabolic incapability for detoxification and the easily distortable intricate developmental processes (tissues and organs differentiation) they are rapidly passing through. It is worth mentioning here that the type II pyrethroid insecticides are highly toxic to fish adults (Prusty et al, 2015); whereas CN has already been reported to be toxic for the developing zebrafish embryos (Shi et al, 2011). Moreover, the combined embryo toxic effects of CN and permethrin in zebrafish have also been reported (Yang et al, 2014).…”