ABSTRACT
Iodomethane is produced in the marine environment by algae and plankton. Model experiments have shown that iodomethane can dissolve a series of metal sulphides, in agreement with some of the results mentioned in the relative literature. While no dissolution of SnS was observed, PbS and HgS were dissolved proportionally with the iodomethane concentration. The two forms of HgS (cinnabar and metacinnabar) behaved differently, with metacinnabar being more soluble than cinnabar. Moreover, iodomethane can methylate lead and tin and mercury can be methylated when methyllead and methyltin compounds are present in the model system. The methylated species were identified using gas chromatography, and there is evidence that lead and tin undergo the same methylation mechanism. Preliminary experiments with natural sediments were performed, but no dissolution of Pb, Sn or Hg was observed. CAPSULE: Iodomethane can solubilize Pb and Hg sulphides, and methylate Pb and Sn, and (indirectly) Hg.
Subject(s)
Hydrocarbons, Iodinated/chemistry , Lead/chemistry , Mercury Compounds/chemistry , Sulfides/chemistry , Tin Compounds/chemistry , Water Pollutants, Chemical/chemistry , Methylation , SolubilitySubject(s)
Metals, Heavy/pharmacokinetics , Mollusca/chemistry , Refuse Disposal , Trace Elements/pharmacokinetics , Air Pollutants/analysis , Air Pollutants/pharmacokinetics , Animals , Antarctic Regions , Environmental Exposure , Environmental Monitoring , Incineration , Metals, Heavy/analysis , Reference Values , Trace Elements/analysisABSTRACT
The concentration of vanadium was measured in 35 samples of the epiphytic lichen Parmelia caperata collected along the coast of the Ligurian Sea (Italy), in order to detect the possible bioaccumulation of vanadium due to a huge crude oil burning occurred in that area in 1991. The cartographic elaboration of data shows a pattern of distribution of vanadium concentrations according to different degrees of deviation from background condition, showing that 8 years later memory of the accident is still detectable in foliose lichen thalli.
Subject(s)
Air Pollutants/pharmacokinetics , Lichens/metabolism , Vanadium/pharmacokinetics , Italy , Petroleum/adverse effects , TreesABSTRACT
Samples of Nephrops norvegicus from the Ligurian Sea were analysed for contents of organic mercury, total mercury and selenium. Results for 37 specimens are reported. Total mercury concentrations increase with size of the specimens. Percentage of organic mercury ranges from 31 to 88% with an average of 58%. Selenium does not correlate with size and the average content is 0.88 micrograms g-1 fresh weight (range 0.30-1.74 micrograms g-1 fresh weight).
