Correlation of socioeconomic status and lead concentration in tap water in Missouri

Lead exposure can have devastating health consequences. This effect is especially detrimental to the developing brain of children. Tap water is the most common source of lead in our diet. There is evidence that lower socioeconomic populations are at higher risk of exposure to tap water with a higher concentration of contaminants. We hypothesized that lead concentration is higher in the tap water of communities with lower per capita income and lower median household income. Using publicly available data from the annual water quality reports, we analyzed the 90th percentile lead levels for municipalities in the state of Missouri. Our results demonstrated that cities in the highest per capita income quartile had significantly lower 90th percentile lead levels than those in the lowest per capita income quartile (2.62±0.28 ppb vs. 4.74±0.83 ppb). Similarly, the highest median household income cities had significantly lower 90th percentile lead levels than those in the lowest median household income quartile (2.44±0.29 ppb vs. 4.62±0.88 ppb). In view of the long-lasting and irreversible health consequences of lead exposure, these findings have important implications when it comes to allocation of resources for mitigating effects of lead on health of populations.