Exposure assessment of a mercury spill in a Nevada school -- 2004.

Background: Although mercury is toxic, few studies have measured exposure in children who handled elemental mercury briefly. In 2004, a student spilled approximately 60 milliliters of mercury at a Nevada school. Within 12 hours, all students were removed from the source of exposure. We conducted an exposure assessment at the school.
Methods: We administered questionnaires and obtained urine samples from students. Using two-sample t-tests, we compared urine mercury levels from students who self-reported exposure to mercury levels of other students.
Results: Two-hundred students participated, including 55/62 (89%) who were decontaminated. The students' geometric mean urine mercury level was 0.36 microg/L (95% confidence interval 0.32-0.40 microg/L). The student who brought the mercury to school was the only one to have an elevated urine mercury level (11.4 microg/L).
Conclusion: Despite environmental contamination, mercury exposure may have been minimized because of rapid identification of the elemental mercury spill and decontamination.