Agricultural soil as a potential source of input of organochlorine pesticides into a nearby pond

MIGLIORANZA, K. S. B., M. A. GONZALEZ SAGRARIO, J. E. A. DE MORENO, V. J. MORENO, A. H. ESCALANTE

Reino Unido

Congreso; Third SETAC World Congress. Tenth Annual Meeting of SETAC-Europe; 2000

SETAC

A study was conducted in Southeastern region of Buenos Aires province, Argentina, to assess an agricultural soil as potential source of organochlorine pesticides (OCPs) for the aquatic biota of a nearby pond. We analysed a compound, g-HCH (lindane), still in use, 3 banned compounds (DDTs, heptachlor an aldrin) and their metabilites (DDD, DDE, heptachlor epoxides, dieldrin and endrin) in soil, bulrush, grass-shrimp and fish by gas chromatography with electron capture detection (GC-ECD). The OCP patterns exhibited differences between soil an biota. The soil was enriched in lindane whereas the hydrophilic pesticides, lindane and heptachlor epoxid, were accumulated in greater quantities in bulrush stems, as they grow within the water column. The presence of heptachlor in soil and its absence in aquatic biota shows its fast degradation rate. Noteworthy, we found low levels of DDT in surface soil and the highest levels in bottom-feeding fish, although they were still bellow permissive levels for human consumption. Because of the relationships between the distribution patterns of OCPs in both environments, our study supports the importance of surface runoff in transporting OCPs from agricultural soil to the nearby pond.