Filling the gaps in ecotoxicological profiles of toxaphene and short chain chlorinated paraffins
|Original title:||Filling the gaps in ecotoxicological profiles of toxaphene and short chain chlorinated paraffins|
|Authors:||Jakub Hofman, Jitka Černohlávková, Blanka Holubářová, Jitka Bezchlebová|
|Field:||Soil contamination adn decontamination incl. pesticides|
|Type:||Article in Proceedings|
|Keywords:||soil; contamination; toxaphene; SCCP|
Many of recognized priority POPs which are in environmentalistic focus can be found in soils in significant concentrations. However, many of these chemicals have not been ecotoxicologically characterized in details yet, especially with respect to soil organisms. The lack of data on ecotoxicity for soil invertebrates or microorganisms is apparent in toxicological profiles (e.g. ATSDR, IPCS), risk assessments (e.g. ECB RAR), and also in scientific articles. To help filling these gaps, two model POPs were chosen: short chain polychlorinated paraffins as widely used industrial chemicals and toxaphene as pesticide banned long ago but still present in some ecosystems due to its persistency. The effects of these chemicals on microbial biomass, respiration and functional diversity and the effects on mortality and reproduction of Enchytraeus crypticus (Enchytraeidae, Oligochaeta) were measured to get information about possible effects on soil microflora and invertebrates. No significant negative effects of toxaphene were recorded at concentrations even 10 ppm, in both tests. Comparing these results with levels supposed in natural no-contaminated soils (i.e. 1-10 ppb) the risk of harmful effects of contemporary toxaphene residues in soils is low. For chlorinated paraffin C12 with 64% of chlorines no significant effects were recorded at 100 ppm concentrations, in both tests. Considering predicted levels for SCCPs in natural non-contaminated soils (i.e. 10 ppb) the risk of harmful effects is also low. However, there are reported levels 1000 times higher at industrial or agricultural sites for both chemicals and there is probable risk of negative effects especially on microbial respiration and reproduction of enchytraeids.