Nutrient intake of working women in Bangkok, Thailand, as studied by total food duplicate method.

OBJECTIVES: To establish a general view of food habits in Thailand, and to make a quantitative assessment of rice dependency of Thai people. DESIGN: Cross-sectional study. SETTING: Community. SUBJECTS: 52 non-smoking and non-habitually drinking adult women in Bangkok participated in the study. METHODS: The participants offered 24 h food duplicates and peripheral blood samples, and underwent clinical examination including anthropometry. The duplicates were subjected to nutritional evaluation taking advantage of the Thai food composition tables (FCTs), and analyzed for eight nutrient elements by inductively coupled plasma mass spectrometry (ICP-MS). RESULTS: The participants took 1630 kcal from 55 g protein (63% from animal sources), 57 g lipid (mostly from vegetable oil), and 224 g carbohydrate (60% from rice) daily. Nutrient intake at lunch was as large as that at dinner. About a half of the women had insufficient energy intake (ie <80% RDA) whereas 4% had an excess (>120%). Protein intake was sufficient in most cases, whereas lipid intake was in excess in more than a half of the women. Ca, Fe, Mg, Zn and possibly P intakes were below the RDA values in many participants. FCT-based estimates agreed well with the ICP-MS measures in cases of Fe and Ca but tended to be greater than the measures by 50% with regard to P. CONCLUSIONS: Lunch as substantial as dinner for Thai urbanites. There was a marked dependency on rice as an energy source. Whereas protein intake is generally sufficient, the intake of Ca (and to a lesser extent Fe) was insufficient in a majority of the study participants. SPONSORSHIP: Dai-ichi Mutual Life Insurance, Japan; the Ministry of Health and Welfare, the government of Japan.

Dietary intake of phytate, zinc and calcium of self-selected diets of Ubon Ratchathani and Bangkok subjects, Thailand.

The dietaty intakes of phytate, zinc and calcium of volunteers in Ubon Ratchathani (northeast Thailand) and Bangkok metropolitan were studied. The selected subjects were 10 men and 10 women from each area. The daily diets were collected for 5 consecutive days using duplicate portion technique. The diets were blended, aliquoted, mixed, freeze-dried and homogenized. Phytate was analysed by using ion exchange coupled with colorimetric method. Zinc and calcium were analysed by atomic absorption spectrophotometer. The total intakes of phytate were 1104.8 +/- 965.2 and 1139.3 +/- 481.1 mg/day for males and females in Ubon Ratchathani, 1304.7 +/- 956.2 and 997.1 +/- 435.1 mg/day for males and females in Bangkok. The zinc intakes were 20.0 +/- 8.8, 12.7 +/- 4.6, 7.7 +/- 1.8 and 6.1 +/- 1.2 mg/day for males and females in Ubon Ratchathani and for males and females in Bangkok, respectively. The calcium intakes were 524.6 +/- 259.9, 379.9 +/- 111.4 for males and females in Ubon Ratchathani and 366.5 +/- 150.5, 286.7 +/- 68.7 mg/day for males and females in Bangkok. The calculated phytate/zinc molar ratios were 7.5, 3.9 for males and females in Ubon Ratchathani and 16.2 and 17.5 for males and females in Bangkok. This study indicated that subjects from Bangkok have a phytate/zinc ratio higher than those in Ubon Ratchathani and higher than 12. This may effect the availability of some micronutrients such as zinc, calcium and iron. The daily intakes of zinc and calcium in these two groups were low compared to Thai RDA.

Non-occupational lead and cadmium exposure of adult women in Bangkok, Thailand.

This survey was conducted to examine the extent of the exposure of Bangkok citizens to lead (Pb) and cadmium (Cd), and to evaluate the role of rice as the source of these heavy metals. In practice, 52 non-smoking adult women in an institution in the vicinity of Bangkok, volunteered to offer blood, spot urine, boiled rice and 24-h total food duplicate samples. Samples were wet-ashed, and then analyzed for Pb and Cd by ICP-MS. Geometric means for the levels in blood (Pb-B and Cd-B) and urine (Pb-U and Cd-U as corrected for creatinine concentration), and also for dietary intake (Pb-F and Cd-F) were 32.3 micrograms/l for Pb-B, 0.41 microgram/l for Cd-B, 2.06 micrograms/g creatinine for Pb-U, 1.40 micrograms/g creatinine for Cd-U, 15.1 micrograms/day for Pb-F and 7.1 micrograms/day for Cd-F. Rice contributed 30% and 4% of dietary Cd and Pb burden, respectively. When compared with the counterpart values obtained in four neighboring cities in southeast Asia (i.e. Nanning, Tainan, Manila, and Kuala Lumpur), dietary Pb burden of the women in Bangkok was middle in the order among the values for the five cities. Pb level in the blood was the lowest of the levels among the five cities and Pb in urine was also among the low group. This apparent discrepancy in the order between Pb-B (i.e. the fifth) and Pb-F (the third) might be attributable to recent reduction of Pb levels in the atmosphere in Bangkok. Regarding Cd exposure, Cd levels in blood and urine as well as dietary Cd burden of Bangkok women were either the lowest or the next lowest among those in the five cities.

Lead--the toxic metal to stay with human.

Lead has been known to be toxic to most living things at high dose. It is found naturally in earth and present in almost all parts of the environment, such as foods, air, water, dust, soil, paint, and tissues of living organisms including human. This metal is being used in various aspects including the manufacturing of storage batteries, production of chemicals, paints and gasoline additives. It is also used to make various metal products, e.g. sheet lead, solder, and pipes. Human exposure to lead is mainly from foods and other environments. However, it is expected that exposure to environmental lead is normally excessive and produces toxic effects. The well-known and excessive environmental exposures are air of industrial and heavy traffic areas. Use of leaded gasoline has caused the main lead pollution for years in almost every big city. Therefore, city inhabitants normally exposed to lead much more than those who live in the rural area. The most vulnerable groups at risk to lead exposure are fetuses and preschool age children. Young children in the 2-3 year-old age may be the most at risk for exposure to contaminated soil. Adults are affected when exposure is excessive in the working place and causing lead poisoning. Toxicities are mainly on heme biosynthesis, neurological effects including encepharopathy, peripheral neuropathy, and most importantly on I.Q. deficits. It also affects renal tissues to produce acute and chronic nephropathy and elevated blood pressure. There are studies of lead exposure of various means and the effects on human health, both in children and adults. Lead in environment and human exposure are expected to stay with us for long to come, due the still required lead use in many fields, particularly the use of lead in storage batteries and others. The magnitude of exposure will depend solely on the control of use by not allowing the contamination of lead in our environment to be excessive.

Prevalence of hepatitis B and C virus infection among working women in Bangkok.

A small-scale seroepidemiological survey on hepatitis B and C virus infection was conducted in the vicinity of Bangkok, Thailand, in 1998. Adult women working in a health sciences institution were invited to participate in the study, and 52 subjects (19 to 57 years of age) volunteered to offer peripheral blood. They were non-smoking and non-habitually drinking, and about two thirds of the subjects were married. The sera from the blood samples were assayed for HBsAg, anti-HBs, anti-HBc, and anti-HCV positivities. The serum assay showed that none of the subjects was positive to HBsAg or anti-HCV, but a half of the subjects (50%) were either positive to anti-HBs, to anti-HBc or to the both, thus having experienced HBV infection in the past. The prevalence of the positivities was significantly higher among those at 35-57 years of age than those younger than 35 years. Comparison of the present findings with the results reported in literature suggested that the risk of HBV infection should have been higher than that of HCV infection, that the observed positivity of HBV infection was probably lower than ever reported, and that anti-HCV positivity should be the lowest.

Serum trace metals in chronic viral hepatitis and hepatocellular carcinoma in Thailand.

This study was conducted to determine and compare serum trace metal levels in viral hepatitis-associated chronic liver disease. Of 98 patients aged 43 (+/- 13) [mean (+/- SD)] years, 83 (85%) were seropositive for hepatitis B surface antigen (HBsAg) and 15 (15%) were seropositive for anti-hepatitis C virus (HCV). Twenty-five patients had chronic persistent hepatitis, 32 chronic active hepatitis, 21 post-necrotic cirrhosis, and 20 hepatocellular carcinoma. Determination of fasting serum trace metal levels (zinc, copper, calcium, magnesium, and phosphorus) was performed after the patients had been on a 2-day diet containing 10-12 mg zinc/day. Compared to healthy volunteers (n = 30), serum zinc levels were significantly decreased in patients with chronic active hepatitis, cirrhosis, and hepatocellular carcinoma (P < or = 0.0001), and copper levels were significantly elevated only in patients with hepatocellular carcinoma (P < 0.0001). The overall serum levels of calcium, magnesium, and phosphorus were within normal ranges, and levels of calcium and magnesium correlated with serum zinc (P = 0.01-0.03). Serum zinc levels correlated with bilirubin, albumin, and cholesterol (P = 0.0004 < or = 0.0001), but not with daily urinary zinc excretion. Serum copper levels correlated with alkaline phosphatase and gamma-glutamyltransferase (P = 0.008-0.0001). These results suggested that changes in liver cell pathology compounded by functional impairment may alter the metabolism of trace metals, in particular, zinc and copper. The possible relationship of these changes to the pathogenesis of chronic liver disease is discussed.

High urinary excretion of nitrate and N-nitrosoproline in opisthorchiasis subjects.

About 50% of the population in some provinces of north-east Thailand are infested with liver fluke (Opisthorchis viverrini), and many develop cholangiocarcinoma subsequently. This study was designed to demonstrate possible endogenous formation of N-nitrosoproline (NPRO) in this population. Diet samples, saliva and urine were taken from subjects with and without liver fluke and analysed for nitrate and nitrite; urine was also analysed for NPRO. Nitrate and nitrite levels in saliva were higher in subjects with liver fluke than in those without; total nitrate and NPRO excretion was also higher in this group. Subjects with liver fluke may therefore be more heavily exposed to N-nitroso compounds than others, and may be at higher risk for cholangiocarcinoma.

Nitrate and nitrite in saliva and urine of inhabitants of areas of low and high incidence of cholangiocarcinoma in Thailand.

Cholangiocarcinoma is one of the main liver diseases in northeast Thailand. Associations with exposure to liver fluke and N-nitrosodimethylamine in formation of the tumour have been demonstrated in animals. This study was carried out to compare possible endogenous formation of N-nitroso compounds in inhabitants of areas with low and high incidences of cholangiocarcinoma by examining the levels of nitrate and nitrite in their saliva and urine. Thirty-two subjects (16 males and 16 females) living in the north-east (high incidence) and 12 volunteers (6 males and 6 females) in Bangkok (low incidence) were allowed to take regular meals, and their saliva and urine were collected before, and 30, 60 and 120 min after each meal. Nitrate and nitrite concentrations in saliva of the group in the high-incidence area were significantly higher than those of the group in Bangkok: salivary nitrate was 2-2.8 times higher and nitrite 2-5.6 times higher in the north-eastern group when compared with levels at each corresponding time interval in the low-incidence group. Nitrate levels in urine were also significantly higher in the north-eastern group at some time intervals, but urinary nitrite levels were similar and very low in both groups throughout the day. This finding may indicate a greater possibility of in-vivo formation of N-nitroso compounds in the north-east area than in Bangkok and might be associated with the occurrence of cholangiocarcinoma in north-east Thailand.

Zinc status in normal Thai infants and children.

Serum zinc levels in Thai infants and children from newborn to 14 years were studied. Data showed that serum zinc levels of infants were significantly lower than that of children (P less than 0.0005) although serum zinc levels in infants were low. They appeared to have normal growth and development. Beyond one year of age serum zinc levels increased with increasing age and there was no reduction in serum zinc level in pubertal subjects. Serum retinol binding protein was also studied. It was found to be low at birth and started to increased in the age of 1--5 months, the relationship between serum zinc and serum RBP was not apparent either in the younger age groups or in adult population.