Computerized data treatment for an HPLC-GFAAS system for the identification and quantification of trace element compounds

Liquid chromatographs, coupled with graphite furnace atomic absorption spectrometers, have been widely used for the identification and quantification of trace element compounds. The quantification of the discontinuous signals from the spectrometer defining a chromatographic band is very much a matter of judgement and therefore prone to error. This paper describes a system which links a high-performance liquid chromatograph via a ‘Brinckman’ flowthrough cup to a Hitachi Zeeman graphite furnace atomic absorption spectrometer equipped with an autosampler. The introduction of aliquots from the column effluent and the analysis sequence is computer-controlled through a home-built interface. The signals from the spectrometer are passed through an analoguedigital converter and processed by selectable algorithms. The software offers a variety of options for processing the chromatographic data, such as data smoothing, Gaussian or spline interpolation, and trapezium or Simpson integration

Human Health Risk Assessment For Arsenic: A Critical Review

Millions of people are exposed to arsenic resulting in a range of health implications.This paper provides an up-to-date review of the different sources of arsenic (water, soil and food), indicators of human exposure (biomarker assessment of hair, nail, urine and blood), epidemiological and toxicological studies on carcinogenic and non-carcinogenic health outcomes, and risk assessment approaches. The review demonstrates a need for more work evaluating the risks of different arsenic species such as; arsenate, arsenite monomethylarsonic acid, monomethylarsonous acid, dimethylarsinic acid and dimethylarsinous acid as well as a need to better integrate the different exposure sources in risk assessments

Antimony leaching from cot mattresses and SIDS.

1 Polyvinyl chloride (PVC) cot mattress covers from SIDS cases were investigated as potential sources of soluble (potentially ingestable) antimony in the cot environment. 2 Body fluids (urine, saliva) and proprietary domestic detergents/sterilizing fluids markedly enhanced leaching of antimony from PVC. Release of antimony was also enhanced at both low and high pH and by elevated temperature. The extent of antimony leaching did not correlate well with PVC content of this element. 3 These data do not support the assumption that postmortem analysis of antimony content proves exposure to gaseous antimony trihydride from mattress PVC. 4 Ingestion of antimony released from PVC could account for the high variability associated with reported detectable levels of antimony in liver from both SIDS and other infants. It could also explain suspected additional postnatal exposure to this element, which gives rise to elevated levels of Sb in the hair of some healthy infants

Biovolatilization of antimony and sudden infant death syndrome (SIDS)

1 The aerobic filamentous fungus S. brevicaulis IMI 17297 methylated antimony from Sb2O3 substrate, with the formation of gaseous trimethylantimony (TMA). No evidence was found for the generation of other gaseous antimony compounds by this organism. 2 Biovolatilization of inorganic antimony was greatest during cultivation of the fungus on solid media at 25 degrees C, and occurred more readily from antimony (HI) substrates than from antimony (V) substrates, 3 Under simulated cot environment conditions (CO2 enriched atmosphere, 33 degrees C) the fungus exhibited an altered morphology and a reduced capability to volatilize inorganic antimony from the pure compound. 4 No evidence of antimony biovolatilization from cot mattress PVC was found, unless antimony was released from PVC by heat treatment (at 80 or 100 degrees C). 5 These data suggest that normal cot environment conditions are non-optimal for volatilization of antimony by S. brevicaulis, and that Sb2O3 in cot mattress PVC is not bioavailable. 6 Cot mattress isolates of S. brevicaulis also volatilized antimony (not encapsulated by PVC), whereas those of other filamentous fungi (Penicillium spp,, Aspergillus niger, Aspergillus fumigatus, Alternaria sp.) and of bacteria (Bacillus spp,) did not. 7 The oxidation products of TMA may be the true determinants of toxicity for biogenic antimony gases produced in an aerobic environment