The role of burrowing beds and burrows of the SW Atlantic intertidal crab Chasmagnathus granulata in trapping organochlorine pesticides.

MENONE MIRTA; MIGLIORANZA KARINA SILVIA BEATRIZ; IRIBARNE OSCAR OSVALDO; AIZPUN JULIA ELENA; MORENO VICTOR JORGE

MARINE POLLUTION BULLETIN

Elsevier

Año: 2004 vol. 48 p. 240 - 247

0025-326X

The effect of crab beds and bioturbation activity of the SW Atlantic intertidal crab Chasmagnathus granulata on the organochlorine pesticide (OCP) concentrations in Bahýa Blanca estuary, Argentina were studied. Total OCP concentration was significantly lower inside than outside the crab burrows. Nevertheless, the concentrations from outside the crab beds were lower than from outside crab burrows, which indicated that crab beds act as sinks of sediment-bound OCP due to the bioturbation activities of the crabs. The same distribution patterns were found in all sediments as well as in crabs, being cyclodienes > HCHs > DDTs, although large amounts of metabolites rather than the respective parental were found in the organism showing the capacity of C. granulata for metabolising parental compounds. These more water-soluble compounds are excreted by the faeces and finally removed by tidal flushing to the sea. Our results suggest that crabs when present play a role in the distribution of sediment-bound OCP and the crab beds are modifiers of the dynamic of organic pollutants in estuarine areas.Chasmagnathus granulata on the organochlorine pesticide (OCP) concentrations in Bahýa Blanca estuary, Argentina were studied. Total OCP concentration was significantly lower inside than outside the crab burrows. Nevertheless, the concentrations from outside the crab beds were lower than from outside crab burrows, which indicated that crab beds act as sinks of sediment-bound OCP due to the bioturbation activities of the crabs. The same distribution patterns were found in all sediments as well as in crabs, being cyclodienes > HCHs > DDTs, although large amounts of metabolites rather than the respective parental were found in the organism showing the capacity of C. granulata for metabolising parental compounds. These more water-soluble compounds are excreted by the faeces and finally removed by tidal flushing to the sea. Our results suggest that crabs when present play a role in the distribution of sediment-bound OCP and the crab beds are modifiers of the dynamic of organic pollutants in estuarine areas.ýa Blanca estuary, Argentina were studied. Total OCP concentration was significantly lower inside than outside the crab burrows. Nevertheless, the concentrations from outside the crab beds were lower than from outside crab burrows, which indicated that crab beds act as sinks of sediment-bound OCP due to the bioturbation activities of the crabs. The same distribution patterns were found in all sediments as well as in crabs, being cyclodienes > HCHs > DDTs, although large amounts of metabolites rather than the respective parental were found in the organism showing the capacity of C. granulata for metabolising parental compounds. These more water-soluble compounds are excreted by the faeces and finally removed by tidal flushing to the sea. Our results suggest that crabs when present play a role in the distribution of sediment-bound OCP and the crab beds are modifiers of the dynamic of organic pollutants in estuarine areas.C. granulata for metabolising parental compounds. These more water-soluble compounds are excreted by the faeces and finally removed by tidal flushing to the sea. Our results suggest that crabs when present play a role in the distribution of sediment-bound OCP and the crab beds are modifiers of the dynamic of organic pollutants in estuarine areas. 2003 Elsevier Ltd. All rights reserved.2003 Elsevier Ltd. All rights reserved. Keywords: Organochlorine pesticides; Estuaries; Chasmagnathus granulata; Crab beds; Bioturbation; SedimentsOrganochlorine pesticides; Estuaries; Chasmagnathus granulata; Crab beds; Bioturbation; Sediments 1. Introduction Organochlorine pesticides (OCP), although banned in the Northern Hemisphere since the 1970’s due to their detrimental effects to wildlife, are still in use for controlling vector diseases and pests in the agricultural areas of the Southern Hemisphere. The occurrence of OCP residues in the SW Atlantic aquatic environment is the result of past and present use. Because of their properties, such as hydrophobicity and high persistence, they can be found mainly in environmental sink compartments such as sediment and biota (Kraaij et al., 2002). However, macroinvertebrate