Effects of atrazine on growth and sex differentiation, in juveniles of the freshwater crayfish Cherax quadricarinatus

C. MAC LOUGHLIN; I. CANOSA; G. SILVEYRA; L. LÓPEZ GRECO; E. RODRIGUEZ

ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2016 vol. 131 p. 96 - 103

0147-6513

The effect of the herbicide atrazine was assayed in early juveniles ofthe redclaw crayfish Cheraxquadricarinatus. Four cohorts of juveniles (a total of 280 animals) wereexposed for 4 wk to each one of three atrazine concentrations (0.1, 0.5 and 2.5mg/L) or a control (0 mg/L), from a commercial formulation having 90% of activeprinciple. At the end of the exposure, no significant (p>0.05) differencesin either mortality or molting were noted. However, the weight gain and theprotein content of abdominal muscle decreased significantly (p<0.05) in thehighest atrazine concentration as compared to control, indicating that atrazineacted as a relevant stressor, although at a concentration higher than thosereported in the environment. Besides, the proportion of females increasedprogressively as the atrazine concentration increases, being significantly(p<0.05) higher than that of controls at the highest concentration assayed.Both macroscopic and histological analysis revealed a normal architecture ofgonopores and gonads in both control and exposed animals. The obtained resultsstrongly suggest that atrazine could be causing an endocrine disruption on thehormonal system responsible for the sexual differentiation of the studiedspecies, increasing the proportion of female proportion without disturbing thegonad structure.