Arsenic Exposure and OGG1 Expression

The study subjects included a total of 299 Ba Men residents from the sub-villages of Wulan, Jianshe, Fengchan, and Xinyao located in Sha Hai Village, Hangjin Hou County, and the subvillages of Miaohao and Xigelian, located in Sheng Feng Village, Wu Yuan County (Figure 1). These subvillages were selected because most residents have been exposed to a wide range of As levels in drinking water from the artesian wells for > 10 years. Before subject selection, well-water samples of the homes from these subvillages were collected and analyzed for As concentrations. The study subjects were selected according to the criteria set for the study design focusing on the As effects on OGG1 expression at low doses (≤200 μg/L). The criteria included a) approximately 70% of subjects with As exposure levels from nondetectable to 200 μg/L and 30% with As exposure levels > 200 μg/L, with exposures of at least 5 years; b) approximately equal numbers of males and females and equal numbers of smokers and nonsmokers; and c) age ranging from 11 to 60 years. Questionnaires were administered to all participants to obtain demographic information, history of well use, diet, smoking, occupation, pesticide use, and medical information. Diagnosis for skin hyperkeratosis, depigmentation, and hyperpigmentation was based on the China national standards for diagnosis of arsenicosis (People’s Republic of China 2000 ). Skin hyperkeratosis is the presence of benign wart-like growths on the skin. Skin hyperpigmentation is the presence of dark pigmentation, and depigmentation is the presence of pale or light brown color on the skin.
This study was conducted according to the recommendations of the Declaration of Helsinki (World Medical Association 1989 ) for international health research. All subjects gave written informed consent to participate in this study. The research protocol met the requirements for protection of human subject certification and was approved by the U.S. EPA.