Description:
Lead is an environmental toxicant that affects virtually every system in the body (ATSDR 2007). In children, lead decreases intelligence, growth and hearing; causes anemia; and can cause attention and behavior problems (CDC, 1991). Young children are particularly susceptible to lead poisoning because they absorb far more lead from their environments than do adults and because their central nervous systems are still developing (CDC 2005). For children under 6 years of age, the Centers for Disease Control and Prevention (CDC) has defined an elevated BLL as ≥5 micrograms per deciliter (µg/dL), but there is evidence for subtle effects at even lower levels (CDC 2005). The CDC Advisory Committee on Childhood Lead Poisoning Prevention recommended that CDC replace the use of a reference value with an upper value limit based on the 97.5% of the BLL distribution in U.S. children: 5 µg/dL (CDC 2012). Sources of lead exposure include lead-based paint, industrial emissions, cottage industries (e.g. informal battery recycling), lead soldered cans and water pipes, lead glazed ceramics, and traditional medicines (CDC, 2002a; CDC, 2005).
Several urban neighborhoods in Philadelphia, Pennsylvania, have a history of soil lead contamination due, in part, to lead-emitting industry as well as the legacy of lead-based paint and leaded gasoline emissions. The point source of interest for this study was the John T. Lewis site (a.k.a., Anzon facility), where a large emitter formerly operated in the Kensington community of Philadelphia (Figure 1). Lead paint was produced at the site from 1849 to 1996. The facility used numerous kilns, oxidizing furnaces, and corroding beds to make its lead-containing products. Over the years, plant emissions, equipment malfunctions, and fires at the facility released lead-containing particulates into the surrounding community. The John T. Lewis facility was closed in 1996 and eventually redeveloped into a multi-use commercial complex/shopping center. Residential structures in the study area have long been co-located alongside other industrial, commercial, and service facilities in this neighborhood, where as many as 12 were suspected to have operated in the past (Figure 1).
During July 2014, the CDC, Agency for Toxic Substances and Disease Registry (ATSDR), and City of Philadelphia Department of Public Health (PDPH) conducted a study in Philadelphia. The community areas have been subject to various environmental and public health investigations since the 1970s. However, previous investigations were limited by their use of convenience samples. We conducted a study to quantify the risk of elevated BLLs among children using a representative population-based survey design. The objectives of the study were to: 1) describe child BLLs in the target communities; 2) identify risk factors and sources of lead exposure among these children; 3) describe environmental lead levels among enrolled households; and 4) compare study findings with existing data sources. The U.S. Environmental Protection Agency (EPA) Region 3 collaborated with the public health agencies and provided funding to conduct the study.
The target communities comprised ZIP codes 19125 and portions of 19122, 19123, 19133 and 19134. The neighborhoods in the study area are Kensington, Olde Kensington, Port Richmond, Northern Liberties, and Fishtown (Figure 1). The demographic characteristics in the study area (using complete ZIP code level data) are as follows: percent pre-1950 housing: 85.0–88.0%; median household value: $159,900–$193,200; percent rental housing: 30.6–35.1%; percent households with African Americans: 5.9–43.1%; and percent households with children <5 years: 6.0–7.6% (U.S. Census 2011). Using Philadelphia tax assessor data, Figure 2 depicts the age of housing in the study area. There is a concentration of housing built before 1900 surrounding the site of interest, and extending toward the northwest.
CS289146-A
PHLchild_lead_assessment_2014-508.pdf