[Detection of serum PICP and PINP and COL1alpha1 DNA sequence analysis in patients with arsenic poisoning in Dazhuyuan Town, Ankang area in southern Shaanxi Province].

OBJECTIVE: To 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). METHODS: This 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. RESULTS: The 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). CONCLUSION: Hair 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.

[Pilot experiment of fluorine fixing ratio of coated lump stone coal fuel].

The pilot experiment on coated lump stone coal fuel selected from 16 families in Haoping Shanxi were studied. 8 families burned coating high fluorine lump stone coal with lime, clay and low fluorine anthracite, 8 families burned untreated lump stone coal. The results show that the fluorine-fixing ratio at treated group was 75.0% when coal fluorine compared with coal cinder fluorine. In comparison with untreated group, the concentration of door air fluoride lowered 85.7%, SO2 lowered 75.0%, dust lowered 55.3%.

[Regularity of flourine release from fluorine-rich coal combustion in the fluorine poisoning area].

Laboratory experiments and in situ measurements inside farmer's houses indicate that the fluorine concentration of indoor air was positively related with the fluorine content in the consumed coal (R = 0.612, P<0.01), but fluorine content in the coal had no effect on the release rate of coal fluorine under the usual combustion temperature of about 1000 degrees C. The release rate of coal fluorine varied versus combustion temperature ranging from 200 to 1200 degrees C, following a "S" curve pattern, increasing slowly under 300 to 700 degrees C, but quickly under 700 to 1000 degrees C, and then slowly again before finally reaching 100% under 1100 to 1200 degrees C, this curve can be fit by Logistic equation. The release rate of coal fluorine usually depends upon the existence status of fluorine and the chemical and mineral components of the coal. The fluorine in soft coal or anthracite from Guizhou is released more quickly than in bone coal from Southern Shanxi, with the former almost completely released under 1100 degrees C but the later almost completely released under 1200 degrees C. The combustion temperature of civil stoves is at most 1000 degrees C, under which averagely 86.9% of the fluorine in coal from Guizhou and 80.6% of that in bone coal from Southern Shanxi is released.