Environmental studies have identified mercury pollution in the Northern Adriatic Sea (Italy). High- level methyl mercury exposure is a known cause of neurodevelopmental disorders. However, the exposure-effect relation at levels <10ppm is controversial. To assess the possible health effects of prenatal methyl mercury exposure through maternal fish consumption, we conducted an epidemiologic cohort study in a mercury polluted area of the Adriatic Sea. We identified all the children born between 1999 and 2001 to women who were resident in two coastal fishing towns. A comparison group was identified inland. A total of 243 children were enrolled. Their mothers were interviewed approximately two months after delivery to determine a variety of covariates and the type, quantity and origin of fish consumed during pregnancy. Total mercury (THg) and methyl mercury (MeHg) were assessed in maternal hair and breast milk and in the child's hair. The children were evaluated after age 18 months with a physical examination and the Denver Developmental Screening Test II (DDST II). Statistical analyses matched by residential area are not presented since they were not associated with fresh fish consumption, THg or MeHg exposure level or neurodevelopmental outcomes. To date 52 children have been evaluated. After adjustment for a number of potential confounders, preliminary results indicate that the fine motor adaptive score on the Denver Developmental test is inversely related to maternal hair THg. These pilot findings are suggestive of an association between children's fine motor skills and their prenatal methyl mercury exposure from maternal fish consumption. However, only a small number of the cohort have been tested and more extensive testing with more sensitive and specific tests is needed to determine if these findings persist.

The main objectives of our study were to estimate the impact of a mercury cell chlor-alkali (MCCA) complex in Rosignano Solvay (Tuscany, Italy) on the local environment and to assess mercury exposure of inhabitants living near the plant. Measurement campaigns of atmospheric Hg near the MCCA plant showed that the impact of the emitted Hg from the industry on the terrestrial environment is restricted to a close surrounding area. Total gaseous mercury concentrations in ambient air of inhabited area around the MCCA plant were in the range of 8.0–8.7ng/m3 in summer and 2.8–4.2ng/m3 in winter. Peaks of up to 100ng/m3 were observed at particular meteorological conditions. Background levels of 2ng/m3 were reached within a radius of 3km from the plant. Reactive gaseous mercury emissions from the plant constituted around 4.2% of total gaseous mercury and total particulate mercury emission constituted around 1.0% of total gaseous mercury emitted. Analysis of local vegetables and soil samples showed relatively low concentrations of total mercury (30.1–2919μgHg/kg DW in the soil; <0.05–111μgHg/kg DW in vegetables) and methylmercury (0.02–3.88μgHg/kg DW in the soil; 0.03–1.18μgHg/kg DW in vegetables). Locally caught marine fish and fresh marine fish from the local market had concentrations of total Hg from 0.049 to 2.48μgHg/g FW, of which 37–100% were in the form of methylmercury. 19% of analysed fish exceeded 1.0μgHg/g FW level, which is a limit set by the European Union law on Hg concentrations in edible marine species for tuna, swordfish and shark, while 39% of analysed fish exceeded the limit of 0.5μgHg/g FW set for all other edible marine species. Risk assessment performed by calculating ratio of probable daily intake (PDI) and provisional tolerable daily intake (PTDI) for mercury species for various exposure pathways showed no risks to human health for elemental and inorganic mercury, except for some individuals with higher number of amalgam fillings, while PDI/PTDI ratio for methylmercury and total mercury exceeded the toxicologically tolerable value due to the potential consumption of contaminated marine fish.

Because of increasing awareness of the potential neurotoxicity of even low levels of organomercury compounds, analytical techniques are required for determination of low concentrations of ethylmercury (EtHg) and methylmercury (MeHg) in biological samples. An accurate and sensitive method has been developed for simultaneous determination of methylmercury and ethylmercury in vaccines and biological samples. MeHg and EtHg were isolated by acid leaching (H2SO4-KBr-CuSO4), extraction of MeHg and EtHg bromides into an organic solvent (CH2Cl2), then back-extraction into Milli-Q water. MeHg and EtHg bromides were derivatized with sodium tetrapropylborate (NaBPr4), collected at room temperature on Tenax, separated by isothermal gas chromatography (GC), pyrolysed, and detected by cold-vapour atomic fluorescence spectrometry (CV AFS). The repeatability of results from the method was approximately 5-10% for EtHg and 5-15% for MeHg. Detection limits achieved were 0.01 ng g-1 for EtHg and MeHg in blood, saliva, and vaccines and 5 ng g-1 for EtHg and MeHg in hair. The method presented has been shown to be suitable for determination of background levels of these contaminants in biological samples and can be used in studies related to the health effects of mercury and its species in man. This work illustrates the possibility of using hair and blood as potential biomarkers of exposure to thiomersal.

A deep comprehension of environmental problems requires a systematic and multidisciplinary approach involving technical, biomedical and environmental issues, as well as social, economic and political information. The intrinsic heterogeneity of environmental and biomedical data makes difficult to establish an explicit correlation between them, thus entangling still more the environmental problem. A new multidisciplinary approach to manage environmental problems and support the safeguard of citizens health from mercury pollution is proposed by the EMECAP (European Mercury Emission from Chlor-Alkali Plants; Contract N° QLK4-CT-2000-00489) project. The project, which involved twelve partners from six European countries (Italy, Norway, Poland, Romania, Slovenia and Sweden), tested and validated this new methodology on three different Mercury Cell Chlor-Alkali (MCCA) Plants located in Italy, Poland and Sweden. The methodology includes innovative mercury monitoring devices, biomedical and environmental methods and databases, a mercury dispersion model and a data mining software to investigate possible relationships among mercury emissions, environmental damages and onset of pathologies in human population living in the neighbourhood of mercury sources.

The amounts of the 19 elements As, Br, Ca, Cd, Ce, Co, Cr, Cs, Fe, K, La, Mo, Na, Rb, Sb, Sc, Se, Sm, and Zn in 92 lyophilized autopsy human liver samples from normal subjects have been analyzed by instrumental neutron-activation analysis (INAA). For intercomparison and quality control ten samples were independently analyzed in two institutes, the Institute of High Energy Physics in China and the “Jožef Stefan” Institute in Slovenia. Most of the element contents determined by the two institutes were in quite good agreement, even though different experimental conditions were applied, indicating the reliability of the analytical results. Analysis of the chemical species of mercury present in the ten liver samples was also performed in Slovenia. Possible differences between the element content of male and female liver samples were studied by means of Student’s t-test, but significant differences were found only for Ce, Co, Fe, La, Mo, and Zn. The results obtained were also compared with those reported from other areas of the world; no appreciable differences were observed. Correlation among the various elements in the human liver samples was studied using multivariate statistics. It was found that there was relatively close correlation between some elements, for example As–Fe, Ca–Fe, Cd–Co, Cd–Zn, Mo–Zn, Co–Se, Cs–Rb, Br–Rb, Sc–Sm, La–Sm, La–Ce, etc.; these correlations could be rationally explained by the similarity of the electronic structures of the elements and/or their physiological functions in the human body.

Natural gas contains various forms of inorganic and organic Hg species. In order to control and improve the efficiency of an industrial facility for mercury removal from natural gas at the INA-Naftaplin gas treatment plant, Molve, Croatia, a comprehensive environmental monitoring program, including mercury measurement in air, was established. Generally, total mercury concentrations in air are very low (e.g. below 10 ng.m-3) and therefore potentially subject to analytical errors (e.g. contamination). In order to control Hg contamination in air, a cost effective method, based on biomonitoring using in-situ lichen species and/or transplanted lichens specie Hypogymnia physodes was developed and optimised in recent years. The present work represents further refinement of the methodology including normalisation to geochemical background. In the present study two geographical areas were studied: (a) the INA Naftaplin Gas Treatment Plants in Croatia, where the efficiency of an industrial facility for removal of Hg from natural gas was investigated, and (b) the mercury mining area, Idrija, Slovenia. The lichen Hypogymnia physodes from a pristine area was transplanted to representative locations presented for periods of 3, 6 and 12 months during 2000/2003. In addition soil samples were collected at all sampling locations for geochemical and calculation of enrichment factors. Samples of soil samples were prepared according to standard procedures for determination of trace and major elements in soil. Determination of total mercury was performed by cold vapour atomic absorption CV AAS and MeHg by extraction/ethylation/chromatographic separation and detection by CV AFS, while other elements were performed by the instrumental neutron activation analysis INAA. The results shawed that the concentration levels of practically all elements are increased with time. These increases are mainly connected with a deposition of local soil dust, which is confirmed with the normalization of the original data for transplanted lichens with Sc. The elements that can be directly associated with the natural gas pumping and processing facilities are Hg, Ba and Br. An estimate was made for the average concentrations of Hg in the air, which was considerably elevated at stations close to technological setting for natural gas tretament, particularly during the exposure period from 6 to 12 months. The approach was validated by in Idrija with continuous monitoring of Hg in air as well as in lichens. Apart from Hg some other elements were closely evaluated. A number of elements that showed an increased enrichment in lichens are those probably associated with agricultural activity (Cu, Pb, Zn) as well as engine exhausts (Pb, Sb, Ni) or smelting and burning of fossil fuels (Sr, Zn).

Profiles of dissolved gaseous mercury (DGM) concentration were systematically measured on a wide geographical scale for the first time in the Mediterranean basin during the international oceanographic cruise MED-OCEANOR on board the R/V Urania of the National Research Council of Italy from 14 July to 10 August 2000. Generally, DGM levels increase from the surface to the first hundred meters and remain constant down to the bottom, suggesting that DGM is produced not only in surface water via photo-induced reactions, but also in deep water as a consequence of bacterial activity, even if it is not possible to exclude a contribution of the geothermal activity at the bottom. The Western Mediterranean basin resulted to be characterised by an average DGM concentration value (0.088pM) in surface water, lower than that observed in the Eastern basin (0.211pM).

The purpose of the present work was to develop a simple, rapid, sensitive and accurate method for the simultaneous determination of inorganic mercury (Hg(2+)) and monomethylmercury compounds (MeHg) in natural water samples at the pg L(-1) level. The method is based on the simultaneous extraction of MeHg and Hg(2+)dithizonates into an organic solvent (toluene) after acidification of about 300 mL of a water sample, followed by back extraction into an aqueous solution of Na(2)S, removal of H(2)S by purging with N(2), subsequent ethylation with sodium tetraethylborate, room temperature precollection on Tenax, isothermal gas chromatographic separation (GC), pyrolysis and cold vapour atomic fluorescence spectrometric detection (CV AFS) of mercury. The limit of detection calculated on the basis of three times the standard deviation of the blank was about 0.006 ng L(-1) for MeHg and 0.06 ng L(-1) for Hg(2+)when 300 mL of water was analysed. The repeatability of the results was about 5% for MeHg and 10% for Hg(2+). Recoveries were 90-110% for both species.

Lake Velenje is located in one of the most polluted regions ofSlovenia, the Šalek Valley. The major source of pollution is the coal-fired thermal power plant in Šoštanj (ŠTPP). In the past, dumping of coal ash directly into Lake Velenje and drainage water from the ash disposal site resulted in unique chemical characteristics of the lake water, such as very high pH (10–12) and high concentrations of heavy metals. The introduction of a closed cycle ash transport system in 1995resulted in a very fast recovery of the lake water quality. The aim of our study was to establish the sources, fate and distribution of mercury in Lake Velenje. In order to establishrecent sources of mercury, total mercury and methylmercury concentrations were measured in various environmental samples(lake inflows, outflow, rainwater, sediments, etc.). Total mercury and methylmercury concentrations were measured at thesurface and at different depths to establish mercury cycling, its transport and chemical transformations in the lake. Generalwater quality parameters (such as pH, Eh, O2, temperature,TDS, conductivity) were also determined. The results show that the major sources of mercury in Lake Velenje are lake inflows and wet deposition. Total mercury andmethylmercury concentrations in the water column are very low (total mercury: 0.2–2.7 ng L-1; methylmercury: 20–86 pg L-1) and can be compared to other non-contaminated freshwater lakes. These results suggest that the major form of mercury emitted from thermal power plant stacks is volatile Hg0, whichhas no or very little influence on the nearby surroundings, but rather is subject to long-range atmospheric transport.

The Idrija mine, Slovenia has severely enhanced the mobilisation of Hg by mining activities, and Hg-laden material remains in the region. The tailings and contaminated soils are continuously eroded and serve as a continuous source for the river, the flood plains and the Gulf of Trieste. The paper presents data of the recent study which aims to assess the extent of contamination of Gulf of Trieste after the closure of the Hg mine. Mercury and methylmercury were measured in various environmental compartments (estuarine and marine waters, sediments, and organisms) during 1995-97 period. Data obtained show that even 10 years after closure of the Hg mine, Hg concentrations in river sediments and water are still very high and did not show the expected decrease of Hg in the Gulf of Trieste. A provisional annual mercury mass balance was established for the Gulf of Trieste showing that the major source of inorganic mercury is still the River SoCa while the major source of methylmercury is the bottom sediment of the