ARSENIC DOSE AND ITS RELATION TO CARDIOVASCULAR RISK AMONG RESIDENTS IN MIDDLE TAIWAN

Abstract

ISEE-34 Introduction / Aim: Arsenic has been found to be abundant in general, and much attention has been paid to the southwestern Pacific region. Blackfoot disease was found to be endemic in the southwestern coast of Taiwan, due to the ingestion of artesian well water with high arsenic concentrations. Even today, researchers still observe high rates of cancers and various vascular diseases in this area. However, much less information is known for the general population in Taiwan. Methods: In order to investigate arsenic body load in community residents and to examine the associated factors for both exposure and cardiovascular effects, we carried out a cross-sectional study of residents from industrial and non-industrial areas of middle Taiwan. A random sample, stratified for age (35-, 45- and 55-) and gender, was taken during 2002.09 ∼ 2003.03, using household surveys, where interviews were conducted by public health nurses. Clinicians performed heath checkups in health care units, where fasting venous blood samples were collected and blood pressure was measured. Total arsenic levels in hair, blood, and urine were quantified by inductive coupled plasma-mass spectrometry (ICP-MS), after standardized pre-treatment and quality control including assurance tests had been carried out. Results: Hair arsenic concentration, in the inorganic form, was significantly higher in industrial (0.06 μg/g hair) when compared to non-industrial (0.04 μg/g hair) areas (p=0.002). Use of underground water (odds ratio (OR)=1.97, p=0.003) and male gender (OR=15.4, p<0.001) are independent factors associated with increased arsenic level in hair, when considering occupation and life style of the subjects. Hair arsenic level was demonstrated to be an important predictor of metabolic syndrome, next to age and gender. The excess risk for arsenic load was most significant in the 35–44 age group. The pattern for the increased risk was similar for hypertension (OR=1.5, p=0.098), when all the potential risk factors were taken into consideration. Increased plasma glucose concentrations with increasing hair arsenic levels was profound in diabetic patients (r=0.25, p=0.05). Conclusion: This first report on internal arsenic exposure associated with increased risk of metabolic syndrome and hypertension in the community is worth noting, for the prevention of high prevalence of the diseases in industrialized countries.