Abstract

ANDRADE HERRERA, Moises et al. Presence of organochlorine pesticides and characterization of biomarkers in wild mice living in crop fields. Therya [online]. 2018, vol.9, n.3, pp.209-218. ISSN 2007-3364.  https://doi.org/10.12933/therya-18-600.

The use of pesticides in crops bordering conservation areas poses risks for wildlife incidentally exposed; its effects in the Yucatan Peninsula, Mexico, are still unknown. Wild mice that inhabit farming land play a key ecological role, and can also be used as bioindicators of wildlife exposure to pollutants. The objectives of this work were to determine the presence of organochlorine pesticides (OC) in liver and evaluate the seasonal response of enzymatic biomarkers (BM) such as acetylcholinesterase (AChE), glutathione-S-transferase (GST), and catalase (CAT). Wild mice (Mus musculus) were captured between June 2015 and April 2016 in a watermelon crop of a rural community in Quintana Roo, Mexico. Individual mice were sacrificed in situ, followed by tissue dissection (liver, brain and skeletal muscle). Pesticides were determined by gas chromatography; BM activity was estimated by spectrophotometry. We captured 35 individuals, with a capture success of 2.33%. The prevailing OCs detected were drines in both climatic seasons. The rainy season influenced the activity of biomarkers to a greater extent, since AChE showed a lower activity (16 % and 40 % in brain and liver, respectively). GST was activated during the same season (77 % higher), while CAT did not show significant differences between seasons. There was no significant correlation between OC concentrations and biomarker activity, except for drines and AChE in the brain. OC concentrations recorded in the present work are below (2- and 20-fold lower) those reported in other works on rodents under controlled conditions. BM activity suggests that rainfall seem to exacerbate the effects of pesticides on mice; however, it seemingly does not pose a risk for their survival. The use of wild mice as bioindicators is a valuable and practical tool to detect disturbances derived from the use of pesticides in agricultural areas. Further research is recommended using a broader BM battery to identify those pollutants with the most severe effect on the physiology of wild animals incidentally exposed to pesticides.

Keywords : Acetylcholineterase; catalase; glutathione-S-transferase; biomarkers; Mus musculus; organochlorine pesticides; wildlife.

        · abstract in Spanish     · text in English     · English ( pdf )