Figure 3

Evaluation of dose response for arsenic exposure and hypertension. Blue symbols indicate studies conducted in populations with low arsenic levels in drinking water (average < 50 μg/L); black symbols indicate studies conducted in populations with moderate-to-high arsenic levels in drinking water (average > 50 μg/L). The size of each data point is inversely weighted based on the inverse of the variance of the estimated log OR. For the Wang SL et al. (2007) study, actual arsenic levels for each hair tertile were not provided, and values defining the arsenic exposure tertiles were approximated based on the geometric mean of hair arsenic.