Records of organochlorine pesticides DDT, HCH, PeCB and HCB in the southwest of Buenos Aires Province, Argentina

NORMA TOMBESI; KARLA POZO; ALVAREZ, MÓNICA; ANDRÉS H. ARIAS; PETRA PRIBYLOVA

Pto. Madryn

Congreso; IV Reunión Argentina de Geoquímica de la Superficie (IV RAGSU); 2016

IPEEC, CESIMAR, UJuanBocsco, UTNFRCH

Thirteen superficial sediment/soil samples used in this study were collected from differentsites along the Bahia Blanca Estuary and surrounding sites, located in the Buenos AiresProvince southwest, Argentina, to assess the concentration levels and spatial distribution of12 selected organochlorine pesticides (OCs). Despite the official ban and restriction on theusage of these pesticides, their presence was detected in all samples. ΣOCs in soil/sedimentsranged between 0.20 and 1040.44 ng g-1 dw (mean = 82.37 and SD = 276.6 ng g-1 dw). DDTs(sum of DDD, DDE, and DDT) ranged from 0.08 to 1039.95 ng g-1 dw (mean = 81.31 and SD= 276.7 ng g-1 dw), HCHs (sum of 􀀀-HCH, 􀀀-HCH, 􀀀-HCH and 􀀀-HCH) from 0.08 to 0.88 ngg-1 (mean = 0.43 and SD = 0.23 ng g-1 dw). Lower concentrations were found for PeCB (mean= 0.095 and SD 0.17 ng g-1 dw) and HCB (mean = 0.56 and SD 1.7 ng g-1 dw). DDTs weredetected in significant concentrations in Bahia Blanca and Dorrego sampling locations;despite this, a major reductive dechlorination process of DDTs to DDEs under aerobicconditions was suggested to be in course. On the other side, HCHs were found in higherproportions at Cuatreros, Maldonado, Galvan, and PBB locations. In comparison to otherworldwide locations and to the world coastal sediment concentrations range, in general,soil/sediment DDTs and HCHs levels were in the low/medium range with exceptionally highDDT levels hotspot. According to international criteria about sediment quality guidelines forDDTs and Lindane (Arias et al., 2010), the levels found in this study are consistent with lowto intermediate ecotoxicological risk assessment.