Cadmium exposure in Thai populations from central, northern and northeastern Thailand and the effects of food consumption on cadmium levels.

The aim of the present study was to investigate the association between cadmium body burden and the areas of exposure in Thailand, as well as blood pressure levels, the types and frequencies of foods, and alcohol consumption. A total of 182 healthy adult Thai subjects of both genders (89 males, 93 females) ages 18 to 57 years old weighing 40-95 kg were included in this study. Participants were residents from three main areas of Thailand: Pathum Thani Province (central Thailand; n=50), Khon Kaen Province (northeastern Thailand; n=43) and Mae Sot District, Tak Province (northern Thailand; n=89). The total amount of cadmium excreted in urine over 2 hours (microg/g creatinine) was used as an indicator of long-term cadmium exposure. Quantitation of cadmium was performed using electrothermal (graphite furnace) atomic absorption spectrometry (GFAAS). The urinary cadmium excreted displayed a normal frequency of distribution. Significantly higher mean cadmium levels were observed in subjects residing in Mae Sot, Tak Province (0.63 +/- 1.41 microg/g creatinine) and Khon Kaen (0.51 +/- 0.76 microg/g creatinine) compared to Pathum Thani Province (0.23 +/- 0.35 microg/g creatinine). The proportion of subjects with elevated blood pressure was significantly higher in the group exposed to higher (n=39) as opposed to lower (n=5) levels of cadmium. There were no significant differences in the mean total amounts of cadmium excreted in the 2-hour urine samples from subjects who consumed different types of meat and offal, or from those who consumed them at different frequencies.

Selected risk factors, human papillomavirus infection and the p53 codon 72 polymorphism in patients with squamous intraepithelial lesions in northeastern Thailand.

Risk factors for cervical squamous intraepithelial lesions (SIL) including human papillomavirus (HPV) infection and the p53 codon 72 polymorphism were investigated in a case-control study with 103 cases and 105 controls in Northeastern Thailand. Increased risk for SIL was observed for age at menarche (odds ratio (OR) = 2.2; p< 0.005), age at the first sexual intercourse (OR=2.4; p< 0.05), number of sexual partners (OR=2.7; p< 0.005) and partners' smoking history (OR=2.3-3.2; p< 0.01). Prevalence of malignant type of HPV infection in the control and SIL groups was 18.1% and 60.2%, respectively. HPV infection significantly increased risk for SIL 6.8-fold (p< 0.001). HPV-16 infection was the commonest (31 out of 62 carriers) in SIL patients and highly associated with risk. The p53 codon 72 polymorphism was not identified as a genetic risk for SIL in this study, as demonstrated in Thai cervical cancer. Therefore, to prevent cervical neoplasia or HPV infection, inclusion of knowledge on sexual behavior and effects of smoking into public health programs is important and, at the same time, a nation-wide screening scheme for cervical abnormalities including HPV-typing is a high priority in Thailand.