PubMed · 13104356
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B H JOHNSON. 1953. Simple method for cleaning mercury.. https://doi.org/10.1093/ajcp%2F23.11_ts.1186
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The preparation and characterization of a soil reference material (SOIL-1) from a site polluted with mercury due to the past mercury mining in Idrija, Slovenia is reported. Homogeneity tests and intercomparison exercises for total (T-Hg) and methylmercury (MeHg) were performed. In addition, selective sequential extraction was applied for Hg fractionation, and multielemental analyses were performed by k(0) standardization neutron activation analysis (k(0)-INAA) and inductively coupled mass spectrometry (ICP-MS) for other trace elements. Comparison of different analytical methods, as well as the distribution of data were critically evaluated using descriptive statistics and analysis of variance (ANOVA). Due to the nugget effect (cinnabar particles representing more than 90% of the mercury), homogeneity for T-Hg determination was difficult to achieve. The intercomparison exercise indicated that in order to obtain comparable results for total mercury (T-Hg) sample decomposition by HF must be performed. These data are then in good agreement with non-destructive methods such as k(0)-INAA. Accepted reference values calculated taking into account the results obtained by six and three laboratories, respectively, were 67.1+/-11.3 mg kg(-1) for T-Hg and 4.0+/-1.3 ng g(-1) for MeHg (95% confidence intervals). However, the results obtained for Hg fractionation displayed significant differences in the organically bound fraction and elemental Hg. Results obtained by two laboratories using totally different analytical protocols for other elements showed excellent agreement for most elements. In summary, the results obtained for the SOIL-1 sample were of sufficient quality to suggest its use for quality control in laboratories dealing with mercury contaminated soils.
Mercury is one of the most toxic and hazardous pollutant which occurs in the environment in different chemical forms, of which methylmercury is the most dangerous. Recently it was recognised that long-term anthropogenic inputs of mercury into environment resulted in the global mercury pollution and it was concluded that action should be taken to quantify the pollution sources and reduce human-generated releases of mercury. This paper presents new data on mercury levels in aquatic sediments from about 15 Croatian rivers, lakes and estuaries. It also brings data on mercury concentrations in soils from eight different regions of Croatia. Distribution of mercury species is discussed in more details for the Sava River, the Krka estuary and the Kastela Bay on the eastern Adriatic coast. Results show that sediments and soils from Croatia are generally not contaminated by mercury, except for some rivers and coastal locations under direct anthropogenic influence.
In the town of Idrija, Slovenia, the world's second largest mercury mine was active for 500 years and about 37,000 tons of mercury has been lost in the environment. Mercury is still drained from soil, riverbed and floodplains and transported with the Idrijca and Soca Rivers to the Gulf of Trieste. A part of inorganic mercury is methylated either in the river system, or later in the coastal area, and, due to its bioaccumulation and biomagnification represents potential danger to human health. A 1-D aquatic model MeRiMod was used to simulate hydrodynamics and sediment transport in the river system from Idrija to the Soca River mouth. Transport of particle bound and dissolved mercury as well as potential net methylation of mercury in the river system was simulated. The simulation of an observed flood wave with 20-year recurrence period was performed in order to validate the model. Methylation was simulated at lower discharges, as higher methylation rates occur in such conditions. The measurement data and the MeRiMod model were also used to establish a historical mercury mass balance of the Idrijca and Soca Rivers catchment. Sediment core data from the Gulf of Trieste and the measured concentrations from floodplains were used to verify and calibrate the model. Simulations of different high discharges were performed as most of the transport of particulate mercury occurs within flood wave conditions. Compared to the measurements, the results of the model showed an agreement within an order of magnitude, for the transport of total mercury mostly within a factor of 4, and for the methylation within a factor of 5. However, proper trends of the phenomena were obtained by simulations. The combination of modelling and measurements has resulted in some interesting conclusions about the phenomenon of the transport and transformations of mercury in the observed river system.