Phthalates in underground waters of the Zagreb area

To determine whether and in what concentrations the underground waters, stream waters, spring water, and tap water from the Zagreb area contain phthalates -- compounds used as plastic softeners, which have recently been ascribed carcinogenic, mutagenic, and teratogenic effects.

The presence of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), benzylbutyl phthalate (BBP), diethylhexyl phthalate (DEHP), and dioctyl phthalate (DOP) was determined in a total of 96 samples of underground waters, stream waters, and tap water from the Zagreb area between February and June 1998. Identification and quantification of phthalates were performed by the method of gas chromatography (GC-ECD), with a detection limit of 0.005 microg/L.

The presence of one or more phthalates was demonstrated in 93 out of 96 (97%) water samples. The measured values ranged from 0.005 to 18.157 microg/L. Phthalates were detected in 76 out of 77 (98%) underground water samples. The mean level of all phthalates present in the water samples was 4.879 microg/L. Median test yielded a significantly increased level of phthalates in the underground waters from Jakusevac (sampled in February 1998) and Trebe , which are Zagreb and Samobor city waste dumps, as compared with other sites in the study (overall median=3.785; chi-square=22.682; p<0.001). Phthalates were found at a mean concentration of 3.363 microg/L in all 10 water samples from the Sava river, the major source of the Zagreb alluvium underground waters. In case of drinking water, phthalates were detected in 7 out of 9 (78%) samples, at a mean concentration of 0.887 microg/L. As expected, DEHP was the most commonly detected phthalate, found in 78 (81%) water samples.

The highest phthalate concentrations were recorded in underground waters directly related to the proximity of a waste dump. The levels of phthalates recorded in this study were lower than those reported from other countries and did not present a threat to human health. Environmental phthalate monitoring should be continued and their maximum allowed concentrations should be prescribed by regulations.