DIELDRIN POLLUTION IN THE RIVER HOLME CATCHMENT, YORKSHIRE

Dieldrin concentrations were measured during 1976 and 1977 in the River Holme and some of its tributaries, Yorkshire, England. The presence of dieldrin arises from its use as a mothproofer in the textile industry. Concentrations were measured from both water and sediment samples from each site. The highest levels of dieldrin were found below sewage works outfalls as the textile mills were discharging their effluent to sewer, not direct into the river. Stations above sewage outfalls had lower concentrations. Less than 30% of the dieldrin was associated with particles of less than 0.7 μmin diameter. Concentrations of dieldrin in this river catchment were thought to be high enough to have a biological effect and this aspect is briefly discussed. © 1979.