Soil contamination by some organic micropollutants related to sewage sludge spreading.

The aim of the present publication is to give some information on soil contamination by 4 different micropollutant classes due to sewage sludge spreading. The soil under research shows an accumulation of light molecular weight PAHs and PCBs, DEHP and 4-NP just after spreading, but one month later the concentration of these micropollutant groups fall to the concentration detected just before the sludge spreading. As far as the soil concentration is concerned, only PAHs and PCBs are precipitation dependent. Some test plots, enriched during 10 years with fertilisers, pig-dung or sewage sludges show only an increase of the PAH concentrations of the plots amended with sludges. In the same way, the sewage sludge is chiefly responsible for the increase of PCBs in the soils, but pig-dung seems to contain quantities of these micropollutants which have to be taken into consideration.