Smelting Remains a Public Health Risk Nearly a Century Later: A Case Study in Pueblo, Colorado, USA

Abstract

Pueblo, Colorado has a long history of smelting activities, and recent studies raised concerns about lead exposure. This study tested 240 children in Pueblo for blood lead levels (BLLs) and found a significant association between distance from old smelters and children BLLs. Around 7.5% of Pueblo children had BLLs above the Centers for Disease Control and Prevention reference level of 5 µg/dL for elevated BLL, and 18.3% had BLLs between 3.3–4.9 µg/dL. Out of the 36 children who lived near former smelters, 13.9% had BLLs above 5 µg/dL vs. 6.37% for children living away from old smelters. The proportion of Pueblo children with elevated BLL was nearly three times the 2007–2010 United States national average (7.5% vs. 2.6%), and this was higher in the immediate vicinity of old smelters (13.9% vs. 2.6%). Genetic polymorphisms for ALAD-1 or ALAD-2 alleles, which play a role in susceptibility to lead toxicity, were not associated with children BBLs. Around 38.5% of houses sampled near the smelters had topsoil lead levels higher than the Environmental Protection Agency’s benchmark of 400 mg/kg. Our study resulted in the addition of areas of Pueblo to the EPA Superfund National Priorities List in December 2014, and cleanup is currently underway to minimize the public health risks.

ALAD Allelic Frequency and Lead Toxicity in Children Under the Age of Five in a Former Used Lead-Acid Battery Area

“…Shen, et al, 26 studied the gene distribution of the ALAD isozyme phenotypes in 229 children aged 6-10 years who live within a community in which a large smelter is located; they found ALAD1/1 (92%), ALAD1/2 (8%), and ALAD2/2 (0%). Diawara, et al, 27 reported that among 231 children who lived next to smelting activities in Pueblo, Colorado, the United State of America, 94.4% of children had ALAD1/1, 5.6% had ALAD1/2 polymorphisms, and none had ALAD1/1 polymorphism.…”

Spatiotemporal Variation and Pollution Assessment of Pb/Zn from Smelting Activities in China

“…With the growing demand for Pb and Zn resources in China, the environmental problems arising from the Pb/Zn smelting process cannot be ignored. During the smelting of Pb/Zn minerals, a large amount of waste water, waste gas and solid waste is generated; if improperly treated or discharged, it causes soil heavy metal pollution, and ultimately results in harm to human health through the food chain [6,14,[22][23][24]. At present, studies on the environmental release of Pb/Zn during smelting in China are insufficient, and the environmental release and distribution of Pb/Zn at the provincial level is unclear.…”