Long term adverse effects on female fertility by neonatal exposure to endosulfan and glyphosate in rats

GUERRERO SCHIMPF M; INGARAMO P. I.; MILESI M.; LUQUE EH; VARAYOUD J

Mar del Plata

Congreso; LXI Reunión Anual de la SAIC- LXIV Reunión Anual de la SAI- XLVIII Reunión Anual de la SAFE- VII Reunión Anual de NANOMEDAR- V Congreso Nacional de la AACYTAL. Mar del Plata, Argentina, 2016; 2016

Pesticide exposure has been associated with increased risk of long-lasting female reproductive disorders such as altered cyclicity, decreased conception rates and increased pregnancy loss. However, the impact to the exposure to pesticide mixture has received little attention. The aim of the present study was to evaluate the reproductive effects of neonatal exposure to a mixture of low doses of endosulfan and glyphosate commercial formulations. Newborn female rats received on postnatal days (PND) 1, 3, 5, and 7, by s.c injection, a commercial formulation of endosulfan at 600 µg/kg/day (END, n=30), a glyphosate based herbicide at 2 mg/kg/day (GBH, n=30) or a mixture of both pesticides at the before mentioned doses (END+GBH, n=27). The control animals were injected with the vehicle (C=22). On PND90, rats were mated with males of proven fertility and the pregnancy rate was evaluated. Sperm-positive females were sacrificed on gestational day 19 to assess the following reproductive parameters: number of corpora lutea (nCL), implantation sites (nIS) and resorption sites (nRS). The END-group showed a decrease of the nIS while the GBH exposed animals evidenced a higher nRS when compared with the control group. Finally, the binary mixture END+GBH revealed an increased in the nRS, as observed in GBH-group. Developmental exposure to END and GBH commercial formulations induced subfertility as a consequence of pre-implantation and post-implantation loss, respectively. Co-exposure to both formulations led to post-implantation loss indicating a predominant effect of GBH formulation. These results draw attention to the need of more studies on the potential reproductive impact of pesticide mixtures.