Determination of methylmercury, ethylmercury, and inorganic mercury in mouse tissues, following administration of thimerosal, by species-specific isotope dilution GC-inductively coupled plasma-MS
2003 (English)In: Analytical Chemistry, ISSN 0003-2700, Vol. 75, no 16, 4120-4124 p.Article in journal (Refereed) Published
Isotopically enriched HgO standards were used to synthesize CH 3200Hg+ and C2H5199Hg+ using Grignard re-agents. These species were employed for isotope dilution GC-ICPMS to study uptake and biotransformation of ethylmercury in mice treated with thimerosal, (sodium ethylmercurithiosalicylate) 10 mg L-1 in drinking water ad libitum for 1, 2.5, 6, or 14 days. Prior to analysis, samples were spiked with aqueous solutions of CH3200Hg+, C2H 5199Hg+, and 201Hg2+ and then digested in 20% tetramethylammonium hydroxide and extracted at pH 9 with DDTC/toluene. Extracted mercury species were reacted with butylmagnesium chloride to form butylated derivatives. Absolute detection limits for CH 3Hg+, C2H5Hg+, and Hg2+ were 0.4, 0.2, and 0.6 pg on the basis of 3s of five separate blanks. Up to 9% of the C2H5Hg+ was decomposed to Hg2+ during sample preparation, and it is therefore crucial to use a species-specific internal standard when determining ethylmercury. No demethylation, methylation, or ethylation during sample preparation was detected. The ethylmercury component of thimerosal was rapidly taken up in the organs of the mice (kidney, liver, and mesenterial lymph nodes), and concentrations of C2H5Hg+ as well as Hg2+ increased over the 14 days of thimerosal treatment. This shows that C2H5Hg+ in mice to a large degree is degraded to Hg2+. Increased concentrations of CH3Hg + were also observed, which was found to be due to impurities in the thimerosal.
Place, publisher, year, edition, pages
2003. Vol. 75, no 16, 4120-4124 p.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-26484DOI: 10.1021/ac0342370Local ID: 11036OAI: oai:DiVA.org:liu-26484DiVA: diva2:247033