Investigation of Heptachlor, Heptachlor epoxide and Aldrin in sediments, macrobenthos and Caras fish (Carassius carassius)

OCPs (Organochlorine pesticides) are part of various contaminants that are able to accumulate in organisms and transfer through the food chain, due to their high fat solubility and persistence in the environment .The aim of the present study was to examine the levels of Heptachlor, Heptachlor epoxide and Aldrin in sediments, macrobenthos (Chironomidae) and Caras fish (Carassius carassius) at 8 stations (in the west side, 2 in the central part and 3 in the east side) in West Lagoon of Anzali wetland (Abkenar) in the spring of 2013. The pesticides concentrations were analyzed using the Moopan method and Gas chromatography-mass spectrometry (GC-MS). Heptachlor epoxide had the highest concentrations with a mean of (6.01±4.42) ppb and (0.41±0.09) ppb in fish and sediment samples respectively. In addition, the highest average concentration of pesticides in macrobenthos (Chironomidae) samples was related to Aldrin with a mean of (0.16±0.07) ppb. The highest levels of all three pesticides were found in the sediments from the east of the Abkenar lagoon. The highest levels of Heptachlor, Heptachlor epoxide, and Aldrin in fish were recorded in the central and eastern part of Abkenar and in Chironomidae samples in the central and western part of Abkenar. The overall order of pesticides levels were west>central>East parts in Abkenar In the present study, concentrations of heptachlor, heptachlor epoxide, and Aldrin in sediments were higher than the Canadian standards (TEC: Threshold effect concentration). None of the concentrations of the pesticides detected in fish samples were higher than the standards recommended by Europe Standards) EU (in macrobenthos samples, the highest average concentration of pesticides was related to Aldrin and all of the toxins (Heptachlor, Heptachlor epoxide and Aldrin) were below the LOQ (Limit of Quantification) standard. Analysis of variance (ANOVA) of Heptachlor epoxide in sediment, Heptachlor in fish and Aldrin in Chironomidae samples revealed a significant difference (P<0.05). According to the results of the study, biomagnification can be observed in the food chain.