Combined chemical analyses and biomonitoring at Avedoere wastewater treatment plant in 2002

Influent - effluent monitoring by comprehensive chemical analyses was conducted at the Avedoere wastewater treatment plant (WWTP) during 2002. In one programme, the same samples were tested for algal toxicity by the ISO 8692 method. Based on evaluation of 17 hazardous substances (including 7 heavy metals), there was a quite good agreement between calculated and measured toxic units. In another programme, influent - effluent monitoring for 11 pharmaceuticals and specific hormones showed high removal rates, except for sulphamethizol and furosemide. High removal is probably due to WWTP operation with long SRTs. Effluent biomonitoring of freshwater mussels showed only bioaccumulation for: diethyl-phthalate, LAS, EOX as well as Cr and Ni. Surprisingly, no bioaccumulation could be observed for 100 other specific organic compounds and 8 other heavy metals (including Hg, Cd and Pb).