[Effects of humic acid on lipid peroxidation in arsenosis prevalent areas].
OBJECTIVE
To explore the causes of blackfoot disease in Taiwan.


METHODS
Experiments to induce lipid peroxidation by arsenic and humic acid were made in vitro. Arsenic was determined for the water sampled from the arsenosis prevalent areas in Inner Mongolia and blackfoot disease prevalent areas in Taiwan and humic acid determined for the extracts of the coal rich in arsenic sampled from Guizhou Province in China by MDA-TBA colorimetry.


RESULTS
Experiments found that humic acid could induce lipid peroxidation caused by sodium salt of unsaturated fatty acids in vitro in a weak and unstable manner, which could be promoted by 0.05 mmol/L of Fe(+ +) and not by 1 mmol/L As(2)O(3). The extent of lipid peroxidation caused depended on the sources, constituents and structure of humic acid samples, those from Inner Mongolia ranked the highest, those from Guizhou and Taiwan the medium and the commercial humic acid (Aldrich Co. in the US) the lowest. The experiments also found that lipid peroxidation caused by commercial humic acid presented a dynamic process in the existence of trace amount of iron, and humic acid could decompose the products of lipid peroxidation.


CONCLUSIONS
The experiments suggested the relations of humic acid and arsenic to iron and other transition elements in the blackfoot disease prevalent areas and areas with an environment rich in arsenic and humic acid.
Yu
X
X
Institute for Geochemistry, Chinese Academy of Sciences, Guiyang, Guizhou 550001.
Lu
F
F
Zheng
B
B
Huang
T
T
Gao
R
R
Liu
C
C
Hong
Q
Q
D020261:Arsenic Poisoning / Q000378:metabolism*; D006812:Humic Substances / Q000494:pharmacology*; D007501:Iron / Q000494:pharmacology; D015227:Lipid Peroxidation / Q000187:drug effects*; D013624:Taiwan
D006812:Humic Substances; D007501:Iron