Potential for Biodegradation of Phthalic Acid Esters in Marine Regions

Abstract

Di-(2-ethylhexyl) phthalate was the major phthalic acid ester in the Mississippi River estuary, with mean levels of 0.1 mug/g (dry weight) in surface sediments, 1.0 mug/liter in river water, and 0.7 mug/liter in delta water. Bacteria that grew aerobically on dibutyl phthalate and o-phthalic acid were readily detected in the sediments and water. Pure cultures of bacteria were isolated on seven different phthalic acid esters from freshwater and marine sources. The marine isolates were taxonomically diverse and grew on a variety of phthalic acid esters. Dibutyl phthalate and o-phthalic acid supported growth in full-strength synthetic sea-water medium, but Na -dependent catabolism was demonstrable only for o-phthalic acid.