FATE OF DI-2-(ETHYLHEXYL)PHTHALATE IN 3 SLUDGE-AMENDED NEW-MEXICO SOILS

The degradation, volatilization, and adsorption of Di-3-(ethylhexyl)phthalate (DEHP) **1**4C were monitored in three calcareous soils from New Mexico amended or unamended with sewage sludge. Evolution of **1**4CO//2 was the only mechanism of loss of DEPH from these soils. No volatilization of parent compound or organic metabolites was detected. The effects of sewage sludge on DEHP degradation varied with soil, DEHP concentration, and sludge incubation time. As a result, 50% disappearance time varied from 8 to 72 d, depending on treatment interactions. Degradation of DEHP was greater in two sandy loams than in a clay soil. Preliminary data suggest extensive adsorption of DEHP by all soils with no effect of sewage sludge additions.