Zinc humic acid

Paulauskis, J.D. and R.W. Winner. 1988. Effects of water hardness and humic acid on zinc toxicity to Daphnia magna Straus. Aquat. Toxicol. 12 273-290. 

Winner, R.W. and J.D. Gauss. 1986. Relationship between chronic toxicity and bioaccumulation of copper, cadmium and zinc as affected by water hardness and humic acid. Aquat. Toxicol. 8 149-161. 

Benzofuran derivatives are rare in petroleum, where sulfurated heterocycles predominate among heterocyclic compounds. Benzofurans and 2,3-dihydrobenzofurans are found, however, in the 200°-270° fraction of the distillate of California crude oil, with dibenzofurans and naphthobenzofurans.123 Alkyl-dibenzofurans have been traced in the 275°-305° fraction of petroleum with alkylnaphthalenes, 4-methyl-dibenzofuran among others.124 The distillation of humic acids with zinc powder is said to give benzofuran and hydrobenzofuran derivatives.125... 

Figure 4.6. Fourier transform infrared spectra of humic acids (HAs) and fulvic acids (FAs) isolated from pig slurry (PS), unamended soil (PSO, and soils amended with 90 and 150m3ha 1yr 1 of PS for 7 years (PS90 and PS150, respectively). Reprinted from Hernandez, D., Plaza, C., Senesi, N., and Polo, A. (2006). Detection of copper(II) and zinc(II) binding to humic acids from pig slurry and amended soils by fluorescence spectroscopy. Environ. Pollut. 143, 212-220, with permission from Elsevier, and from Hernandez, D., Plaza, C., Senesi, N., and Polo, A. (2007). Fluorescence analysis of copper(II) and zinc(II) binding behavior of fulvic acids from pig slurry and amended soils. Eur. J. Soil Sci. 58, 900-908, with permission from Blackwell Publishing.

Hernandez, D., Plaza, C., Senesi, N., and Polo, A. (2006). Detection of copper (II) and zinc(II) binding to humic acids from pig slurry and amended soils by fluorescence spectroscopy. Environ. Pollut. 143, 212-220. 

Randle, K., and Hartmann, E. H. (1987). Applications of the continuous flow stirred cell (CFSC) technique to adsorption of zinc, cadmium and mercury on humic acids, Geoderma 40, 281-296. 

From the extraction in NaOH solution we may consider the stability order of Me-humic acid complexes. The order is Cu Zn> Mn> Fe. Copper forms more stable complexes with humic acid than zinc, in accordance with data available in literature for, soils (9-12), as well as manganese which forms complexes... 

Copper, lead, cadmium, zinc and probably other divalent transition metal ions appear to compete for similar coordination sites in humic and fulvic acids. However, in a fashion analogous to the case with Fe" some workers have identified more than one site for a particular ion. At least three have been suggested as being available in humic acids for Pb" forms complexes... 

There is a good deal of information on the inorganic forms of several elements in many rocks, soils and coals, but much remains to be done on the organic associations of trace elements. For example copper, lead and zinc are associated with humic acids, probably through carboxyl or phenolic groups (Saxby, 1969 Nissenbaum and Swaine, 1976). Vanadium porphyrins occur in petroleum (Davis, 1967), but the form of vanadium in coal has not been established. In most shales and coals, trace elements probably occur partly inorganically and partly organically bound. 

Soil is a complex matrix containing humic acids that have ion-exchange abilities with metals, such as lead, cadmium, bismuth, mercury, and zinc which disturb the ecological system, taking into account the atmospheric circuit ... 

Of the other forms of nonresidual associations, some metal-organic compounds, for example, fulvic and humic acids, have been shown to be particularly effective in the transfer of (toxic) metals from inorganic matter into organisms 51). According to Table II, where data of humate extractions with O.IN NaOH are compared, these effects should be more relevant for iron, copper, zinc, and lead in the sample from the Rhine River than in the sediment material from Lake Constance. The other nonresidual metal associations (easily reducible, carbonates, moderately reducible forms) partly indicate higher percentages in Lake Constance sediments (Mn and Pb), whereas others (chromium, copper, and zinc) are enriched in the Rhine sample. 

In the O.IN NaOH extractable fraction (which is assumed to reflect the humic acid phases) of the Rhine sediment, PCF values are particularly high for iron, copper, and lead, exhibiting a slight increase in the fine-grained particles compared with the silt-sized material. For the sample from Lake Constance, the concentration factors in the humate phase have been found to be 11 and 40 for copper, 9 and 12 for iron, and 5 and 9 for chromium, in the pelitic and silty sediment fractions, respectively. Similar concentration factors of trace metals in the NaOH-extractable matter have been observed by Chen et al. (14) for chromium, lead, copper, and zinc, whereas iron and manganese showed no significant association with this fraction. 

Zinc is an essential nutrient that is present in all organisms. Although biota appears to be a minor reservoir of zinc relative to soils and sediments, microbial decomposition of biota in water can produce ligands, such as humic acids, that can affect the mobility of zinc in the aquatic environment through zinc precipitation and adsorption (Callahan et al. 1979). 

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