Background lead and cadmium exposure of adult women in Xian City and two farming villages in Shaanxi Province, China

The objectives of the present study are: (a) to clarify the current levels of environmental exposure to lead (Pb) and cadmium (Cd) in Shaanxi Province in China in comparison with levels in other parts of mainland China; (b) to examine if there is any urban-rural difference in Pb and Cd exposure; and (c) to quantify the role of cereals as the dietary source of environmental exposure to these metals. For this purpose, triplet surveys on lead and cadmium exposure were conducted in the provincial capital of Xian and two farming villages A and B in Shaanxi Province, China in 1997. The grand geometric mean for lead (Pb) intake via foods (Pb-F), Pb in blood (Pb-B) and Pb in urine as corrected for creatinine concentration (Pb-Ucr) were 30 micrograms/day, 33 micrograms/l and 5 micrograms/g creatinine, respectively, with significant differences among the survey sites, e.g. Pb-B being higher in Xian (43 micrograms/l) than in the two villages (38 and 22 micrograms/l). The counterpart values for cadmium (Cd) intake via foods (Cd-F), Cd in blood (Cd-B) and Cd in urine (Cd-Ucr) were 6.1 micrograms/day, 0.46 microgram/l and 2.8 micrograms/g creatinine, respectively, with no substantial inter-survey site difference. Thus, it was possible to conclude that, from comparison with the values reported in 1990s literature, the exposure of Shaanxi people to Pb and Cd is no higher than, and even possibly lower than, the levels reported for people in other parts of mainland China. The exposure to Cd was almost exclusively from foods, whereas the exposure to air-borne Pb was large enough in Xian to explain higher Pb-B and Pb-Ucr than the level in Village B despite lower Pb-F in Xian than in Village B. Cereals (wheat, rice, maize and foxtail millet) contributed 26 and 84% of dietary Pb and Cd intake, respectively.

Urban-rural comparison of nutrient intake by adult women in Shaanxi Province, China

Triplet surveys were conducted in the city of Xi' an and two villages (one in the vicinity and the other at a distance) in Shaanxi Province in China in October-November (when agricultural activities were low), 1997, to elucidate nutrient intakes with a focus on possible urban-rural differences. Total food duplicate samples were collected from non-smoking and non-habitually drinking adult healthy women (about 50 subjects per site and 149 in total). The nutrient intakes were estimated from the weight of food items in reference to national food composition tables. On average, the women took 1873 kcal energy, 54 g protein and 37 g lipid per day, with a lipid energy ratio of 18.4%. Both excess and insufficient energy intake was observed as a result of food intake analysis and body mass index determination. With regard to minor nutrient intakes, insufficiency was serious in the case of calcium, vitamin A and vitamin B2, but not with iron. Whereas dependency on plant foods for sources of energy and protein was common to the three regions, Xi' an people consumed more animal foods than those in the villages. Intake of fish and shellfish was quite low throughout the three regions. Among the four types of cereals, wheat was consumed most substantially in the three regions and in three meals (except for the village where people essentially did not take lunch in reflection of low agricultural activities), whereas rice was consumed more in Xi' an than in the two villages. Maize consumption was higher in the two villages (especially for breakfast) than in the city. In contrast, foxtail millet (although in small amounts) was taken primarily in Xi' an and only at the time of breakfast.

Prevalence of hepatitis B and C infection markers among adult women in urban and rural areas in Shaanxi Province, China

In an attempt to investigate possible urban-rural difference in prevalence of hepatitis B and C virus (HBV and HCV, respectively) infection in continental China, triplet surveys on HBV and HCV infection markers (ie, HBsAg, anti-HBs, anti-HBc, and anti-HCV) and serum enzyme levels (AST, ALT and gamma-GTP) were conducted in 1997 on groups of apparently healthy adult women (49 to 50 subjects per group); one group (the City group) was in Xian, the provincial capital of Shaanxi Province, and two others (the Village A group and the Village B group) were in farming villages in the Province some 200 and 25 km away from Xian, respectively. Comparison among the three groups showed that there was no urban-rural difference in prevalence of HBV and HCV infection positive (HBV+ and HCV+) cases and that the overall prevalence of HBV+ and HCV+ cases was 70% and 3%, respectively. HBsAg+ prevalence was however higher in the villages (8% when the two villages were combined) than in the city (2%). HBV infection was not associated in general with apparent increase in emission enzyme levels in the serum, whereas HCV infection might be associated with an increase in ALT, AST and gamma-GTP. The present observation in combination with other previously published results suggests that urban-rural difference will not be remarkable in HBV and HCV infection prevalence in Continental China and that the public health problem is more serious with HBV infection and quite less so with HCV infection.

Influence of medicinal herbs decocted with different utensils on colony formation of gastric carcinoma cells

In order to elucidate the different results obtained in cancer patients with similar condition and symptoms treated by the same medicinal herbs, an investigation of the utensils used for making decoctions was carried out. It was found that the decoction made by means of glassware, enamel and earthenware pots had the best effect of inhibiting the colony formation of human gastric carcinoma cells, the next were the decoctions made by means of unrefined iron pots, stainless steel pots and copper pots, and the worst was that made with aluminium pots. It was also found that there was no difference between the water contained in those utensils and normal saline in the influence on the colony formation of human gastric carcinoma cells. Therefore, it is believed that the difference in effect of the decoctions made by means of different kinds of utensils is not due to the trace dissolution of the utensil materials, but is most likely due to the occurrence of some chemical reactions while making the decoction. That the decoctions made by means of different utensils had different peak values in the absorption spectrum also supports this proposition.