Occurrence/prevalence of polychlorinated biphenyls (PCBs) in Bombus pauloensis from areas with different land uses in Buenos Aires, Argentina

CECCHETTO FRANCO; MAGGI MATIAS; MIGLIORANZA KARINA SILVIA BEATRIZ

Congreso; Congreso SETAC LA; 2021

Bees (Fam. Apidae) are a crucial component in global biodiversity, ecosystems stability and crops production. In the last years, bees have been threatened by a combination of factors, such as habitat loss, pathogens, agricultural intensification and environmental pollution. Polychlorinated biphenyls (PCBs) belong to persistent organic pollutants, currently forbidden and regulated by the Stockholm Convention; however, they are still present in the environment and are matter of concern. In Argentina the social bumblebee Bombus pauloensis, is one of the most prevalent species of the genre, inhabiting natural, agricultural, and urban areas. The aim of this study was to assess the impact of land use (conventional and ornamental plants agricultures, and natural reserve) on the levels of PCBs in B. pauloensis. Females (workers) and males were sampled from a conventional agriculture production area (A1), an ornamental plants field adjacent to an urban solid waste disposal site (A2) and a natural reserve with organic crops production (A3). Analyses were performed by GC-ECD. In general males showed higher levels than females in sites A1 and A3, while in A2 the concentrations were similar between both sexes. In the case of females, the maximum PCBs levels were found in A2 (58,72 ng/g), followed by A1 (40,22 ng/g) and A3 (27,77 ng/g), according to proximity at waste disposal, while in males the order was A1 (70,72 ng/g ) > A3 > A2, where A3 (61,98 ng/g) and A2 (57,29 ng/g) differed slightly. The 3-CB were the main congener groups found followed by 5-CB in both sexes. These results could reflect atmospheric transport as the main source of these pollutants. However, it is not discarded an exposure to local source of heavy chlorinated biphenyls probably due to proximity to solid waste disposal (A2) and the important industrial area located near the sampling site A1- At our knowledge, this work represents the first study about PCBs on wild bees in Argentina and remarks the potential of B. paulensis as a biomonitor of environmental pollution