OBJECTIVETo investigate type I collagen metabolism in patients with arsenic poisoning in Dazhuyuan town, Ankang area in southern Shaanxi province known for high-level exposure to arsenic (As), fluoride (F) and selenium (Se).

METHODSThis case-control study involved 29 patients with arsenic poisoning from Dazhuyuan, a town in Ankang area of Shaanxi province affected by coal-borne endemic arsenicosis. Thirty individuals without arsenic poisoning from Chang'an county of Xi'an city were included as the control group. The serum concentrations of As and Se were determined using a graphite furnace atomic absorption spectrophotometer, and the levels of F detected with a fluoride ion-selective electrode. Enzyme-linked immunosorbent assay (ELISA) was used for assessing serum contents of PICP and PINP, and the sequence of COL1alpha1 gene was analyzed with ABI sequence analyzer.

RESULTSThe contents of PICP and PINP were similar between the two groups, which had also identical COL1alpha1 DNA sequences. After controlling for all the other factors, an inverse correlation was noted between PICP and serum F contents (r=-0.4, P<0.05) and between PINP and hair F content (r=-0.5, P<0.05), but a positive correlation was found between PINP and hair Se content (r=0.5, P<0.05).

CONCLUSIONHair F and Se levels are the major factors affecting PINP synthesis, and increased hair F level is associated with elevated PINP content, whereas hair Se level is inversely correlated to PINP content. But in the patients with arsenic poisoning from Dazhuyuan town, the PICP, PINP contents and COL1alpha1 DNA sequence show no significant alterations, suggesting that hair Se increment abolishes the effect of hair F increment in inducing the decrease in PINP content.