Lipids that contain arsenic in the Mediterranean mussel, Mytilus galloprovincialis

Environmental contextAlthough arsenic-containing lipids are widespread in marine environments, their origin remains unknown. We show that the arsenolipids in a filter-feeding bivalve mollusc closely match those found in marine food sources, including unicellular algae and bacteria. The results demonstrate the role of lower trophic levels in determining the forms of arsenic found in higher organisms. AbstractArsenic-containing lipids, arsenolipids, are widely found among marine organisms, but their origin and possible biochemical roles remain unknown This work describes the diversity and abundance of arsenolipids in the digestive gland and mantle of nine specimens of the Mediterranean mussel, Mytilus galloprovincialis. By using high performance liquid chromatography (HPLC) coupled to both elemental and high-resolution molecular mass spectrometry, we identified 36 arsenolipids including arsenic derivatives of fatty acids, hydrocarbons, sugar-phospholipids and sugar-phytol; 21 of these arsenolipids were identified for the first time and included a new group comprising ether-phospholipids. The arsenic compounds in the mussels show distinct profiles depending on the tissue type, which provide insight into the arsenolipid origin. The results suggest that the presence of some arsenolipids in the mussels is from direct uptake of the compounds, presumably from food, rather than biogenesis within the mussels.

A multi-electrode glow discharge ionization source for atomic and molecular mass spectrometry

A novel multi-electrode glow discharge provides increased sensitivity and analytical flexibility for both atomic and molecular MS determinations.

Radiocarbon Tracers in Toxicology and Medicine: Recent Advances in Technology and Science

This review summarizes recent developments in radiocarbon tracer technology and applications. Technologies covered include accelerator mass spectrometry (AMS), including conversion of samples to graphite, and rapid combustion to carbon dioxide to enable direct liquid sample analysis, coupling to HPLC for real-time AMS analysis, and combined molecular mass spectrometry and AMS for analyte identification and quantitation. Laser-based alternatives, such as cavity ring down spectrometry, are emerging to enable lower cost, higher throughput measurements of biological samples. Applications covered include radiocarbon dating, use of environmental atomic bomb pulse radiocarbon content for cell and protein age determination and turnover studies, and carbon source identification. Low dose toxicology applications reviewed include studies of naphthalene-DNA adduct formation, benzo[a]pyrene pharmacokinetics in humans, and triclocarban exposure and risk assessment. Cancer-related studies covered include the use of radiocarbon-labeled cells for better defining mechanisms of metastasis and the use of drug-DNA adducts as predictive biomarkers of response to chemotherapy.

Origin of arsenolipids in sediments from Great Salt Lake

Environmental contextArsenic is a globally distributed element, occurring in various chemical forms with toxicities ranging from harmless to highly toxic. We examined sediment samples from Great Salt Lake, an extreme salt environment, and found a variety of organoarsenic species not previously recorded in nature. These new compounds are valuable pieces in the puzzle of how organisms detoxify arsenic, and in our understanding of the global arsenic cycle. AbstractArsenic-containing lipids are natural products found predominantly in marine organisms. Here, we report the detection of known and new arsenolipids in sediment samples from Great Salt Lake, a hypersaline lake in Utah, USA, using high-performance liquid chromatography in combination with both elemental and molecular mass spectrometry. Sediments from four investigated sites contained appreciable quantities of arsenolipids (22–312ng As g−1 sediment) comprising several arsenic-containing hydrocarbons and 20 new compounds shown to be analogues of phytyl 2-O-methyl dimethylarsinoyl riboside. We discuss potential sources of the detected arsenolipids and find a phytoplanktonic origin most plausible in these algal detritus-rich salt lake sediments.