These samples were run in duplicate and intra-sample precision was measured. Blood mercury concentrations ranged from 0.74 μg/L to 14.80 μg/L, with a mean of 3.36 μg/L and the 50th percentile at 2.76 μg/L. All sam-ples were above the detection limit and all had errors in precision of less than 10%; the mean error was 1.8% when measured in duplicate.