Ecotoxicological effects of soil-bound pentachlorophenol residues on the microflora of soils

Pentachlorophenol (PCP)-14C was applied to two soils (50 and 200 mg/kg dry weight) and incubated for 20 weeks at room temperature. Total and extractable 14C-residues decreased continuously, whereas soil-bound residues increased. ATP-content, substrate-induced soil respiration and substrate-induced heat output did not recover during decline and binding of PCP; in the soils dosed with 200 mg/kg, ATP-content reached nearly zero. After removal of the extractable 14C-residues by exhaustive extraction, significant effects of the remaining soil-bound residues (6–30 mg/kg) on the microflora of fresh soils were observed only by ATP-content.