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In the last two decades (1990-2012), as part of a comprehensive monitoring of the eco-system, earthworms were collected from four locations in the vicinity of the natural gas production and treatment plant Molve, Croatia. Their tissues were analyzed for total mercury concentration by cold vapour AAS. The range of the median mercury concentration values (wet weight) in earthworms were 0.004-0.283, 0.013-0.260, 0.005-0.317 and 0.009-0.191 μg/g for Molve 9, Molve 10, Molve 11 and Molve 12 location, respectively. Although the results of mercury measurements in earthworm tissues from different locations vary in a wide range of values, integrated results of all measurements during last twenty years period demonstrate small but constant decline in concentration values, especially after the year 2004. Comparing our results with results published in available data from Europe and some areas of Croatian on mercury concentration in earthworms it can be concluded that area investigated in this research belongs to moderately mercury contaminated region. Nevertheless, further eco-monitoring and mercury measurements in various biological samples are important for more complete interpretation of results and will be continued.

Results presented are part of the first going on comprehensive investigation on the toxic heavy metals (Hg, Pb, Cd) contamination in game animals in Croatia. During regular hunting procedures samples (muscle, liver, kidney) of wild boar of 3 different age groups (piglets, < 1 year, n = 17 ; middle-aged animals, around 2 years, n =12 ; adults, >3 years, n =11) from the low land area of Croatia were collected. Concentrations of metals were analyzed using atomic absorption spectrometry and are expressed in &micro ; ; g/g wet weight. Statistical evaluation of results was made by calculating medians and mean values to enable further statistical procedure. In muscle tissue the lowest median concentration was measured for Cd (0.0019 &micro ; ; g/g), lead was present in slightly higher median concentration (0.002 &micro ; ; g/g) while median Hg concentration was the highest (0.009 &micro ; ; g/g). Statistically significant different Cd concentrations were determinated in piglets comparing to middle-aged and adults animals (p

For the last eighteen years (1990-2007), as part of a comprehensive monitoring of the eco-system, hares (n=5) were collected around natural gas processing plant – GTP Molve on eight occasions. Their organs (muscle, liver, kidney and brain) were analyzed for total mercury concentration by cold vapor AAS. The range of the median mercury concentration values (wet weight) in hares organs were 0.001-0.005, 0.010-0.045, 0.020, 0.130 and 0.001-0.015 µ ; g/g for muscle, liver, kidney and brain, respectively. Comparing our results with results published in available literature on mercury concentration in hares it can be concluded that area investigated in this research belongs to low contaminated region by mercury. Achieved results also point to the fact that closed mercury removal system installed in 1993 is effective in mercury removal from natural gas.

Levels of total mercury in the muscle (29 samples) and liver tissue (15 samples) of bluefin tuna (Thunnus thynnus) weighing 100-300 kg were determined by cold vapour atomic absorption (AA) spectroscopy. Tunas were previously captured in the waters of Malta, towed to the farm in the Adriatic Sea and fattened with defrosted herring and sardine for the period of 6 to 7 months. The purpose of the investigation was to determine the magnitude of mercury contamination and to ascertain whether the concentrations in muscle tissue exceeded the maximum level defined by the European Commission Decision (1 μ g/g wet weight). Total mercury concentrations in the muscle tissue of tunas ranged from 0.49 to 1.809 (median 0.899 μ g/g wet weight) while in the liver tissue it was from 0.324 to 3.248 (median 1.165 μ g/g wet weight). Total mercury concentrations in six samples of sardine ranged from 0.050 to 0.072 μ g/g wet weight while two samples of herring contained 0.020 and 0.053 μ g/g wet weight. Twelve out of 29 (41%) muscle samples of tuna contained mercury above the maximum level defined by the European Commission Decision. It is generally believed that mercury levels in Mediterranean fish are higher than those of the other seas or oceans due to numerous deposits of mercury ores and metallic mercury in surrounding countries.

Levels of total mercury in the muscle (29 samples) and liver tissue (15 samples) of bluefin tuna (Thunnus thynnus) weighting 100 – 300 kilos were determined by cold vapor atomic absorption (AA) spectroscopy. Tunas were previously captured in the waters of Malta, towed to the farm in the Adriatic Sea and fattened defrosted herring and sardine for the period of 6 to 7 months. The purpose of the investigation was to determine the magnitude of mercury contamination and to ascertain whether the concentrations in muscle tissue exceeded the maximum level fixed by the European Commission Decision (1 µg/g wet wt). Total mercury concentrations in muscle tissue of tunas ranged from 0.49 to 1.809 (median 0.899 µg/g wet wt) while in liver tissue it was from 0.324 to 3.248 (median 1.165 µg/g wet wt). Total mercury concentrations in 6 samples of sardine ranged from 0.050 to 0.072 µg/g wet wt, while two samples of herring contained 0.020 and 0.053 µg/g wet wt. Twelve out of 29 (41 %) muscle samples of tuna contain mercury above maximum level fixed by the European Commission Decision. It is generally believed that mercury levels in Mediterranean fish are higher than those of the other seas or oceans due to numerous deposits of mercury ores and metallic mercury in surrounding countries. We also have to keep in mind that tunas are highly mobile fish which swim for the whole life what enables them to enter or leave Mediterranean Sea or Atlantic Ocean.

This study, as part of a comprehensive monitoring of the eco-system, was aimed at establishing a relationship between mercury concentration in ambient air and tissues of wild animals in the vicinity of the natural gas processing plant - GTP Molve, Croatia. The study indicates the presence of low ambient air mercury concentrations, being far below the maximum allowable values. During the last measurement period 1999-2001., mercury was detected at levels (4-9 ng/m3) well below worker exposure standards (50 μ g/m3) and a typical ambient air quality toxic standard (10 ng/m3- suggested value for ambient air in Croatia). The range of the median mercury concentration values in hares organs obtained on for occasions in the period 1990-2001 were 0.001-0.0025, 0.001-0.003, 0.007-0.027 and 0.041-0.062 μ g/g in muscle, brain, liver and kidney tissue, respectively. The results of mercury measurements in ambient air and in hare’ s tissues during last decade demonstrate small but constant decline in concentration values. Nevertheless, further eco-monitoring and mercury measurements are important and needed.

Over the last three decades, a multitude of studies have been carried out on the levels of mercury found in cetaceans. Due to its lengthy persistence and high mobility in the marine ecosystem, mercury shows a high level of biomagnification in the upper levels of the food web and the dolphins are typical end-points in the bioaccumulation of persistent pollutants in the pelagic food chain. Beached dolphins found along the coast are an important source of information on marine mammals ; in recent years, they have been found along several coasts. Altogether 17 stranded or by-caught dolphins were collected between 1990 and 1999 aged between

The present study, as part of a comprehensive monitoring of the eco-system, was aimed at establishing a relationship between mercury concentration in ambient air and tissues of wild animals in the vicinity of the natural gas processing plant - GTP Molve, Croatia. The study presents a part of results of mercury concentration measurements in hares present in the wider area around GTP Molve. The results indicate that concentrations are within normal levels. Mean mercury concentration values found in hares’ muscle, liver, kidney and brain tissues recorded in 1999 were lower than those recorded during 1995 and 1990. Mercury concentration measurements in ambient air and in hare’ s tissues demonstrate small but constant decline in concentration values. Achieved results point to the need of further research in order to investigate correlations between particular values so as to be able to make adequate conclusions.

Heavy metal contaminated fish food is a significant source of increased heavy metal levels in intensively bred fish. Concentration of Hg, Pb and Cd in muscle and liver tissues of rainbow trout originated from two fish farms in Croatia during the period 1978-1989. did not exceed MAC with the exception of Cd in a few samples, while in the majority of food samples cadmium concentration was above MAC as regulated by law.

The mercury concentration in muscles, partly in the liver and kidney tissue of various freshwater fish, and in water and pond sediments of many fishponds in Croatia was investigated