Humic substances arsenic

Allard, B. and I. Arsenic. 199L Abiotic reduction of mercury by humic substances in aquatic system — an important process for the mercury cycle. Water Air Soil Pollut. 56 457-464. 

NOM is common in sediments, soils, and near ambient (<50 °C) water. The materials result from the partial decomposition of organisms. They contain a wide variety of organic compounds, including carboxylic acids, carbohydrates, phenols, amino acids, and humic substances (Drever, 1997, 107-119 Wang and Mulligan, 2006, 202). Humic substances are especially important in interacting with arsenic. They result from the partial microbial decomposition of aquatic and terrestrial plants. The major components of humic substances are humin, humic acids, and fulvic acids. By definition, humin is insoluble in water. While fulvic acids are water-soluble under all pH conditions, humic acids are only soluble in water at pH >2 (Drever, 1997, 113-114). 

Cano-Aguilera, I., Haque, N., Morrison, G.M. et al. (2005) Use of hydride generation-atomic absorption spectrometry to determine the effects of hard ions, iron salts and humic substances on arsenic sorption to sorghum biomass. Microchemical Journal, 81(1), 57-60. 

Speciation studies have been focused on relatively few elements, mainly aluminum, antimony, arsenic, chromium, lead, mercury, selenium, and tin. The primary species of these elements studied with ICP-MS detection are presented in Table 3 and they include different oxidation states, alkylated metal and/or metalloid compounds, selenoaminoacids, and selenopeptides. In addition, applications in studies of the pharmacokinetics of metal-based drugs (Pt, V, Au), metalloporphyrins (Ni, V, Fe, etc.), heavy metals in phytochelatins (Cd, Cu, Zn, Hg, etc.) and in humic substances should be mentioned. 

Davis, C. C., Knocke, W. R., and Edwards, M., 2001, Implications of aqueous silica sorption to iron hydroxide Mobilization of iron colloids and interference with sorption of arsenate and humic substances Environmental Science Technology, v. 35, p. 3158-3162. 

Felbeck, G.T., Jr. 1965. Structural chemistry of soil humic substances. Adv. Agron. 17 327-368. Ferguson, J.F., and J. Gavis. 1972. A review of the arsenic cycle in natural waters. Water Res. 

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. 

Alicia Fernandez Cirelli (water quality aquatic ecosystems aquatic humic substances heavy metal pollution use of macrophytes as biosorbents for simultaneous removal of heavy metals biotransfer of arsenic from water to the food chain). Director, Center for Transdisciphnary Studies on Water Resources, Faculty of Veterinary Sciences, University of Buenos Aires (UBA) National Scientific and Technical Research Council (CONICET), Buenos Aires... 

Biogeochemical interactions among the arsenic, iron, humic substances, and bacterial activities in mud volcanoes in southern Taiwan. Journal of Environmental Sciences Health A, 46 (11), 1218-1230. 

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