Case studies and evidence-based approaches to addressing urban soil lead contamination

Abstract

Urban soils in many communities in the United States and internationally have been contaminated by lead (Pb) from past use of lead additives in gasoline, deterioration of exterior paint, emissions from Pb smelters and battery recycling and other industries. Exposure to Pb in soil and related dust is widespread in many inner city areas. Up to 20e40% of urban children in some neighborhoods have blood lead levels (BLLs) equal to or above 5 mg per decilitre, the reference level of health concern by the U.S. Centers for Disease Control. Given the widespread nature of Pb contamination in urban soils it has proven a challenge to reduce exposure. In order to prevent this exposure, an evidence-based approach is required to isolate or remediate the soils and prevent children and adult's ongoing exposure. To date, the majority of community soil Pb remediation efforts have been focused in mining towns or in discrete neighborhoods where Pb smelters have impacted communities. These efforts have usually entailed very expensive dig and dump soil Pb remediation techniques, funded by the point source polluters. Remediating widespread non-point source urban soil contamination using this approach is neither economical nor feasible from a practical standpoint. Despite the need to remediate/isolate urban soils in inner city areas, no deliberate, large scale, cost effective Pb remediation schemes have been implemented to isolate inner city soils impacted from sources other than mines and smelters. However, a city-wide natural experiment of flooding in New Orleans by Hurricane Katrina demonstrated that declines in soil Pb resulted in major BLL reductions. Also a growing body of literature of smaller scale pilot studies and programs does exist regarding low cost efforts to isolate Pb contaminated urban soils. This paper reviews the literature regarding the effectiveness of soil Pb remediation for reducing Pb exposure and BLL in children, and suggests best practices for addressing the epidemics of low-level Pb poisoning occurring in many inner city areas.

New Approaches to Identifying and Reducing the Global Burden of Disease From Pollution

“…Water managers switched supply sources to save money, the involved water engineers inadequately modeled the impacts of water chemistry on internal pipe deposit mineralogy, the surveillance system measured water chemistry from the finished water side of the system but not at the tap, and the public health system had to wait for hundreds of lead poisoned children showing up in clinics before the problem was traced back to its source, over a year later (Hanna-Attisha et al, 2016;Sadler et al, 2017). Even once the water system is ultimately repaired, Flint, like many other older cities in the U.S., suffers from soil lead contamination, which remains unaddressed (e.g., Filippelli et al, 2015)-in Flint, it is likely responsible for~50% of the peak blood lead levels even at the peak of the water crisis (Laidlaw et al, 2017). The links between lead poisoning, criminal misconduct, and the environmental injustice of this situation have been highlighted (e.g., Needleman et al, 2002), but it is not at all unique, and until we more fully integrate the geo-side and health-side in the area of pollution exposure and disease, we are bound to continue failing the health of people, and often the most vulnerable people.…”

Does Involving Parents in Soil Sampling Identify Causes of Child Exposure to Lead? A Case Study of Community Engagement in Mining‐Impacted Towns in Peru

“…There is considerable scope for testing the effectiveness of a more participatory approach, because educational interventions have been shown to reduce child BLL but are not always effective (Hilts et al, 1998). Covering, or replacing, high-Pb soil with clean soil has also been shown to reduce child BLLs (Laidlaw et al, 2017;Lanphear et al, 2003;von Lindern et al, 2003). Reducing indoor dust-Pb loading, has also been connected to decreases in child BLL, especially at higher BLLs (Braun et al, 2018;Haynes et al, 2002), although it appears there are diminishing returns at lower BLL (Braun et al, 2018;Haynes et al, 2002).…”

Lead (Pb) Bioaccessibility and Mobility Assessment of Urban Soils and Composts: Fingerprinting Sources and Refining Risks to Support Urban Agriculture

“…Capping contaminated soil with clean fill at the neighborhood scale has been shown to lower BLLs and prevent soil recontamination, though these plans are often limited by cost and material availability (Filippelli et al, 2015;Hynes et al, 2001;Laidlaw et al, 2017;Mielke et al, 2016). Capping contaminated soil with clean fill at the neighborhood scale has been shown to lower BLLs and prevent soil recontamination, though these plans are often limited by cost and material availability (Filippelli et al, 2015;Hynes et al, 2001;Laidlaw et al, 2017;Mielke et al, 2016).…”

“…To mitigate the recontamination risk, gardeners must annually reapply compost to their raised beds and plots, which can be prohibitively costly and time-intensive for low-income residents. Capping contaminated soil with clean fill at the neighborhood scale has been shown to lower BLLs and prevent soil recontamination, though these plans are often limited by cost and material availability (Filippelli et al, 2015;Hynes et al, 2001;Laidlaw et al, 2017;Mielke et al, 2016).…”