Endocrine Disruption and Transgenerational effect of Atrazine herbicide in the nematode Caenorhabditis elegans life cycle?.

MOYA A, KRONBERG MF, CLAVIJO A, MAZZARELLA D, PAGANO EA,; MUNARRIZ, ER.

Cordoba

Congreso; IV Congreso Argentina de la Sociedad de Toxicología y Química Ambiental.; 2016

SETAC

Introduction: Endocrine disrupting chemicals (EDCs) are exogenous agents that interfere with hormone signaling. A wide range of substances like pesticides, polychlorinated biphenyls and plasticizers cause endocrine disruption. Atrazine (ATZ) is a worldwide used herbicide to control broadleaf and grassy weeds on crops such as corn, sorghum and sugarcane. Reports shown that ATZ have endocrine disruptor activity; nevertheless, their adverse effects on human and animal health are not fully understood. ATZ use was banned in the European Union in 2004 while the Environmental Protection Agency (EPA) approved its use, consequently the safety of ATZ remains controversial. Objective: The aim of this study is to assess ATZ endocrine disrupting effects using the nematode Caenorhabditis elegans as a biological model. Specifically, we were interested in study how the life cycle was affected in second-generation descendent of nematodes treated with low doses of ATZ.Materials and Methods: C. elegans in L4 larval stage were exposed to different concentrations of ATZ (0.001; 0.01; 0.1; 1; 10 mg/l) for 24 hours till they reached adulthood. After the ATZ treatments, worms were washed and keep in culture for two generations (F1 and F2). Nematode growth and reproduction were measured in all three nematodes populations (F0, F1 and F2). Post embryonic development in F1 and F2 was analyzed and percentage of developmental stages was calculated.Results: Second generation (F2) C. elegans, from parental generation treated with low doses ATZ, show a no-monotonic in ?W" shape dose-response curve for growth and reproduction. The maximum effect on growth and reproduction was determinate at 0.001 and 0.01 mg/l ATZ. Results show a 30 and 15% decrease in grown and reproduction respectively compare to the untreated worms. The postembryonic developmental analysis showed a delay in F1 and F2. In this kind of experiments we observed a decrease number of adults worms in F1 and F2 (15 and 30% respectively) from parental generation treated with ATZ (0.001 and 0.01 mg/l ATZ) compared to the control.Conclusions: Our results show that the herbicide ATZ has a transgenerational effect in C. elegans life cycle. Specifically, low doses of ATZ can interfere with the normal postembryonic development till two generation after the worms were of treated with the herbicide. As a consequence of these alterations, low doses of ATZ decrease the growth and reproduction rates in the nematode C. elegans.