Phthalate ester residues--their metabolism and analysis in fish.

During the course of our analysis of fish and other aquatic materials for pesticide residues, unknown components were often detected. Concern about the identity of late eluting gas-liquid chromatographic (GLC) peaks in fish and water extracts led to the identification of phthalic acid esters (PAEs) as environmental contaminants (1). Further study of these contaminants with a GLC-mass spectrometer (GLC-MS) led to their identification as di-2-ethylhexyl phthalate (DEHP) and di-n-butyl phthalate (DBP). Preliminary data from acute toxicity tests indicate that these compounds are relatively low in toxicity. Chronic studies, however, indicate that they may have more subtle effects on reproduction of some aquatic species (2). Residue data obtained from a variety of areas, dietary materials, and samples related to fish rearing operations have established some information on the incidence of PAEs in relation to pesticides and polychlorinated biphenyl contaminants (Table 1). PAE residues in water appeared to be correlated with rivers draining industrialized or heavily populated areas (John Hesse, Michigan Department of Natural Resources, East Lansing, Michigan 1972 personal communication). However, the distribution of PAEs in the aquatic environment remains to be defined. PAEs are commonly used as plasticizers, especially in poly(vinyl chloride) plastics. In