Speciation of mercury in eelgrass (Zostera marina L.): a seasonal study in the Great Bay Estuary, New Hampshire
✍ Scribed by Thomas S. Pannhorst; James H. Weber
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 73 KB
- Volume
- 13
- Category
- Article
- ISSN
- 0268-2605
No coin nor oath required. For personal study only.
✦ Synopsis
The first detailed determination of mercury(II) [Hg(II)] and monomethylmercury cation (MeHg ) concentrations in eelgrass (Zostera marina L.) is described. The rapid and simple method includes digestion by the new reagent tetrabutylammonium bromide/potassium hydroxide, derivatization by sodium borohydride and detection by hydride generation-cold vapor atomic fluorescence spectrometry. Mercury in leaves/stems and roots/rhizomes of eelgrass samples collected near Adams Point of the Great Bay Estuary, NH, from May to November of the 1997 growing season was speciated. The seasonal ranges of concentrations in leaves and stems of eelgrass are: Hg(II), 14.9-40.4 ng Hg g À1 dry weight; MeHg , 1.06-3.89 ng Hg g À1 dry weight. MeHg content averaged 6.9% of total mercury. Analogous values for roots and rhizomes are: Hg(II) 15.4-57.7 ng Hg g À1 dry weight; MeHg 0.91-2.41 ng Hg g À1 dry weight; MeHg averaged 6.4% of total mercury. The non-parametric Kendall test showed that Hg(II) and MeHg concentrations in leaves and stems increased from May to July, then decreased. For roots and rhizomes the Kendall test showed that Hg(II) concentrations were unchanged from May to August, then decreased, and that MeHg concentrations decreased throughout the growing season. The non-parametric Wilcoxon Signed-Ranks method showed no systematic difference in Hg(II) or MeHg concentrations between leaves/stems and roots/rhizomes.