Abstract
This work describes the evaluation of several parameters for preparing a tuna fish candidate reference material (RM) in order to measure its total Hg and methyl-Hg mass fractions by cold vapor atomic absorption spectrometry (CV-AAS) and solid sampling graphite furnace atomic absorption spectrometry (SS-GF AAS). Best results were acquired after extraction with toluene and L-cysteine for 15 min at 80 °C. The parameters investigated were stability of chemical composition during production, homogeneity and analyte segregation. No analyte segregation was observed and the material was shown to be stable even when stored at 50 °C for 10 months. Total Hg mass fraction was 3.03 ± 0.22 µg g-1 by CV AAS, 2.99 ± 0.43 µg g-1 by SS-GF AAS and 2.95 ± 0.15 µg g-1 by direct mercury analyser (DMA). Methyl-Hg mass fraction was 2.49 ± 0.13 µg g-1 by CV AAS and 2.44 ± 0.46 µg g-1 by SS-GF AAS.
Highlights
Mercury (Hg) is a highly toxic pollutant found in a variety of chemical species, among which organic mercury compounds are generally more toxic than inorganic ones
Both inorganic and methyl-Hg can be reduced by NaBH4, depending on the concentration of the reagents used for hydride generation
Considering the results obtained for total Hg and methyl-Hg in raw fish, freeze-dried fish and freeze-dried and cryogenically ground fish (Table 5), there was no influence of sample treatment on the total Hg or methyl-Hg mass fractions since there was good agreement between the results. These results show that the homogeneity of total Hg and methyl-Hg mass fraction distribution was improved in the final steps of reference material (RM) production
Summary
Mercury (Hg) is a highly toxic pollutant found in a variety of chemical species, among which organic mercury compounds are generally more toxic than inorganic ones. Methyl-Hg can affect the immune system, alter genetics, disturb enzyme function and damage the nervous system, including coordination and the senses of touch, taste and sight.[1] Fish and seafood consumption are the main source of methyl-Hg ingestion by humans.[2] The levels of methylHg in large predatory fish such as shark, marlin, swordfish and certain tuna fish species are high, since this compound is bioavailable in aquatic systems, bioaccumulates and biomagnifies in the food chain. According to Codex guideline levels, maximum methyl-Hg levels are set at 1.0 and 0.5 mg kg-1 for large predatory fish and for nonpredatory fishs, respectively.[3] Control and knowledge of Hg levels is important in order to avoid environmental disaster and/or promote toxicological information
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
