Assessment of DDT, HCH and PCB Pollution of Lake Sediments in Poland

In the years 2010–2013, 528 samples of surface sediments were collected from lake depths in the area of Poland. The content of 7 PCB congeners, HCH isomers and p,p’-DDT, p,p’-DDE and p,p’-DDD was determined using the GC-ECD method. The studies showed the common occurrence of organochlorine compounds in lake sediments in Poland. The presence of HCHs, at a concentration above the determination limit, was detected in 83.71% of samples, that of DDTs in 98.86% of samples, and of PCBs in 98.86% of samples. The maximum HCH concentration was 60.7 ng g⁻¹, that of DDTs 602.9 ng g⁻¹, and of PCBs 50.7 ng g⁻¹, while the averages were 6.3 ng g⁻¹, 19.2 ng g⁻¹ and 2.8 ng g⁻¹, respectively. High levels of DDTs are found in sediments of those lakes upon which major towns are located, whereas the highest HCH concentrations are observed in sediments of the lakes upon which holiday centres and agrotourism facilities have developed. The ratio of concentrations of total DDT metabolites to p,p’-DDT was above 2 in almost all samples, and the value was most frequently from several to tens (average 28.3). Sediments of some lakes contain higher concentrations of γ-HCH and DDT metabolites than their PEC values, the content of γ-HCH was higher in 1.89% of the analysed samples, the content of p,p’-DDE in 3.78% of the samples, and the content of p,p’-DDD in 7.38% of the samples. Concentrations of p,p’-DDT and PCB in excess of the PEC value were not found in any of the samples tested.