Comparison of blood lead levels between children in an urban setting and children in a rural setting

Environmental heavy metal exposure is a public health problem that is of great concern because it is highly toxic for children. The urban setting in downtown El Paso is historically known to be contaminated through various sources of contamination of heavy metals. The goal of this study was to compare whether children in a historically contaminated urban downtown area had significantly increased levels of lead exposure as compared to children in a demographically similar rural area approximately 20 miles north of the urban center, while controlling for gender and age. Cadmium and mercury were also measured for comparison purposes. It was predicted that children living in the urban setting would have significantly higher BLLs than children living in the rural community. This was an observational study which included a total of 222 children, 111 children from a rural setting and 111 children from the downtown urban setting. Fewer children were tested in the rural setting, thus all rural children tested were included, and 111 from the urban setting were selected for inclusion based on an age and gender match to the rural children. Blood lead, cadmium, and mercury levels were analyzed with inductively coupled plasma mass spectrometry (ICP-MS). General linear model regression analyses were conducted to determine whether blood lead, cadmium and/or mercury levels were predicted by location, controlling for gender and age. Children living in the urban setting had higher BLLs (2.86, ±1.29), than children living 20 miles north of El Paso (1.11±1.03). A regression analysis revealed a significant association between geographic location and BLLs, (F (3, 218) = 125.13, p \u3c0.000). Blood cadmium and mercury levels did not differ by geographic location. The prevalence of lead poisoning has decreased significantly however low-level lead exposure persists. It is known that BLLs in the ranges observed in the urban sample examined in this study are associated with early neurocognitive deficits and possible long-term effects. While the smelter plant located one mile from the urban setting has been shut down for ten years, continuing contamination exists in the region. Increased efforts should be made to monitor children’s blood lead in this urban community and identify potential contamination sources. Finally, community-based approaches to education are needed for parents, school personnel and children, regarding the potential effects of early chronic low-level lead exposure