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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.

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Fungicides are regularly applied in horticultural production systems and may migrate off-site, potentially posing an ecological risk to surface waterways. However, few studies have investigated the fate of fungicides in horticultural catchments. This study investigated the presence of 24 fungicides at 18 sites during a 5-month period within a horticultural catchment in southeastern Australia. Seventeen of the 24 fungicides were detected in the waterways, with fungicides detected in 63% of spot water samples, 44% of surface sediment samples, and 44% of the passive sampler systems deployed. One third of the water samples contained residues of two or more fungicides. Myclobutanil, trifloxystrobin, pyrimethanil, difenoconazole, and metalaxyl were the fungicides most frequently detected, being present in 16-38% of the spot water samples. Iprodione, myclobutanil, pyrimethanil, cyproconazole, trifloxystrobin, and fenarimol were found at the highest concentrations in the water samples (> 0.2 μg/l). Relatively high concentrations of myclobutanil and pyrimethanil (≥ 120 μg/kg dry weight) were detected in the sediment samples. Generally the concentrations of the fungicides detected were several orders of magnitude lower than reported ecotoxicological effect values, suggesting that concentrations of individual fungicides in the catchment were unlikely to pose an ecological risk. However, there is little information on the effects of fungicides, especially fungi and microbes, on aquatic ecosystems. There is also little known about the combined effects of simultaneous low-level exposure of multiple fungicides to aquatic organisms. Further research is required to adequately assess the risk of fungicides in aquatic environments.