Effect of mercury on the hepato-nephrocitic system of Bombus atratus Franklin (Hymenoptera: Bombini)

Abstract

Most studies related to the disappearance and decreased of Bombus regards population survey and mortality in a particular region or locality. There is not significative studies about the impact of trace metals on the morphology of internal organs of neotropical native bees, despite such toxicants are present in most industrial waste released in air, soil and water. Therefore, the project aims to improve the knowledge of the impact of trace metals, such as mercury (Hg), in important internal organs of these bees. The study will analyze, in a comparative fashion and in replicate, the hepato-nephrocitic system of workers of B. atratus collected in the field and kept under controlled conditions of temperature and humidity bioassays. Experimental groups (n = 10 for each experiment), will receive natural food ad libitum (mixture of pollen, nectar and organic soy flour) and daily 2 mL of solution containing 0.2 ppb Hg (maximum concentration of mercury considered safe for Class II and Class VII waters, CONAMA) and 110 ppb (approximate average value found in honey pots in native stingless bee from Brazil, Argentina, Venezuela and Australia. - Pablo et al, 2012). For the control group (n = 10) will be offered food and 2 mL of mineral water. After exposure of 48h, the bees under crio-anesthesia at 4 oc will sacrificed and their internal organs (dorsal vessel, pericardial cells, fat body and hemocytes) will processed for routine, histochemical and immune-histochemical analyses. (AU)