Migration of phthalates from plastic products to model solutions.

The aim of this investigation was to determine the level and rate of migration of phthalates, compounds used as plastic softeners, from various plastic products into model solutions and to assess the possible adverse effects of the phthalate amounts released on human health, thus to contribute to harmonization of the opinions on the maximal allowed human exposure to these compounds through environmental factors. Nine specimens of plastic toys, 16 specimens of plastic food containers and 10 specimens of other plastic consumer goods were analyzed. The specimens of plastic products were submitted to 10-day action of model solutions. Three model solutions were used: distilled water, 10% ethyl alcohol, and 3% acetic acid. Identification and quantification of the phthalates released were performed by the method of gas chromatography on days 1, 5 and 10 of exposure, at a detection limit of 0.005 microgram/kg. On day 10, the highest level of released phthalates (54.5 mg/kg) was measured in distilled water, followed by 44.4 mg/kg in 3% acetic acid and 32.3 mg/kg in 10% ethyl alcohol. According to plastic product categories, the highest pooled level of phthalates released to all three solutions was recorded for plastic toys (66.2 mg/kg), followed by food containers (37.6 mg/kg) and other consumer goods (27.4 mg/kg). According to plastic product categories, toys showed the most rapid phthalate release, with 65.4% (43.3 of 66.2 mg/kg) of the pooled level of phthalates released to all three solutions recorded on day 1. As indicated by the study results, the levels of phthalates released would not present a hazard for human health, not even over a prolonged period of time. However, data on the highest and fastest pooled phthalate release from plastic toys, and this especially to distilled water simulating salivary action, point to the need of continuous evaluation and amendments of the legislation on phthalates in consumer goods.

Toxic metals in freshwater fish from the Zagreb area as indicators of environmental pollution.

The aim of this investigation was to determine the levels of heavy metals and metalloids in freshwater fish from the Zagreb area. A total of 216 freshwater fish samples from 5 sites were examined: Sava river upstream from Zagreb, Sava river at Zagreb, Sava river downstream from Zagreb, Jarun Lake, and 5 "ecologic" fishponds from the Zagreb surroundings. The metals lead, cadmium, mercury and the metalloid arsenic were determined by the method of atomic absorption spectrometry. The mean pooled levels of lead, cadmium and arsenic in all fish samples were 112.3 +/- 95 micrograms/kg, 8.5 +/- 11 micrograms/kg and 23.5 +/- 36 micrograms/kg, and did not exceed the allowed levels of 1,000 mg/kg, 100 micrograms/kg and 200 micrograms/kg, respectively. In 4 fish samples, the levels of mercury exceeded the allowed limit of 500 micrograms/kg (509, 596, 605 and 788 micrograms/kg), however, the pooled mean level of mercury was 127.8 +/- 90 micrograms/kg. There was no major difference in the levels of heavy metals between the two fish families observed, although the levels of lead, cadmium and mercury were higher in the family Ictaluridae (144 vs. 107 micrograms/kg, 10.4 vs. 8.2 micrograms/kg, and 153 vs. 124 micrograms/kg, respectively), whereas the level of arsenic was higher in the family Cyprinidae (23.8 vs. 21.8 micrograms/kg). Although the Sava river at Zagreb is the main recipient of sewage and wastewater in the Republic of Croatia, the levels of heavy metals were within the allowed limits in all groups of freshwater fish samples, with the exception of 4 samples that contained moderately elevated levels of mercury. Study results suggest that only mercury could be considered a good indicator of environmental pollution, because higher levels of mercury were measured in the fish from the Sava river than in the fish from the Jarun Lake and fishponds from the Zagreb surroundings, considering both pooleded and fish family specified data.

Presence of N-nitrosamines in canned liver patty.

The presence of N-nitrosamines was determined in samples of industrially manufactured liver patty stored at different temperatures for a variable period of time. Sample preparation included steam distillation and extraction of redistilled samples with dichlormethane. The extracts were analyzed by a gas chromatography--mass spectrometry system (GC-MS-SIM). Study results expressed as total N-nitrosamines, including methylethyl-, diethyl- and dibutyl-N-nitrosamines, ranged from 0.0008 to 2.997 mg/kg, which significantly exceeded the recommended value of 0.002 mg/kg. The increase in the formation of N-nitrosamines was directly dependent on the length and temperature of product storage.