Mercury abiotic materials

Techniques for analysis of different mercury species in biological samples and abiotic materials include atomic absorption, cold vapor atomic fluorescence spectrometry, gas-liquid chromatography with electron capture detection, and inductively coupled plasma mass spectrometry (Lansens etal. 1991 Schintu etal. 1992 Porcella etal. 1995). Methylmercury concentrations in marine biological tissues are detected at concentrations as low as 10 pg Hg/kg tissue using graphite furnace sample preparation techniques and atomic absorption spectrometry (Schintu et al. 1992). 

Table 5.5 Mercury Concentrations in Selected Abiotic Materials Material (units) Concentration Reference8... 

A half-life of about 40 days was reported for hexachloroethane in an unconfined sand aquifer (Criddle et al. 1986). Laboratory studies with wastewater microflora cultures and aquifer material provided evidence for microbial reduction of hexachloroethane to tetrachloroethylene under aerobic conditions in this aquifer system (Criddle et al. 1986). In anaerobic groundwater, hexachloroethane reduction to pentachloroethane and tetrachloroethylene was found to occur only when the water was not poisoned with mercury chloride (Roberts et al. 1994). Pentachloroethane reduction to tetrachloroethylene occurred at a similar rate in both poisoned and unpoisoned water. From these results, Roberts et al. (1994) suggested that the reduction of hexachloroethane to tetrachloroethylene occurred via pentachloroethane. The first step, the production of pentachloroethane, was microbially mediated, while the production of tetrachloroethylene from pentachloroethane was an abiotic process. 

Allard B, Arsenic I (1991) Abiotic reduction of mercury by humic substances in aquatic system. An important process for the mercury cycle. Water Air Soil Poll. 56 457-464 Anderson A (1979) Mercury in soils. In Nriagu JW (ed.) The biochemistry of mercury in the environment. Elsevier, Amsterdam, pp 79-112 Azzaria LM, Aftabi A (1991) Stepwise thermal analysis technique for estimating mercury phases in soils and sediments. Water Air Soil Poll 56 203-217 Azzaria LM (1967) A Method of determining traces of mercury in geologic materials. Geol Surv Can, pp 66-54. 

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