American Robin (Turdus Migratorius) Blood Lead Levels May Reflect Elevated Soil Lead Levels: Further Consequences of the Flint Water Crisis

High levels of pollutants often occur in urban environments and can pose a threat to human residents as well as local wildlife. The Flint, Michigan water crisis was caused by the corrosion of pipe infrastructure, resulting in high levels of lead (Pb) leaching into the drinking water. Irrigation with contaminated water may have introduced lead into the soil causing another source of exposure to humans as well as wildlife. A widespread songbird species, the American robin (Turdus migratorius), feeds heavily on earthworms and ingests large amounts of soil during foraging. This study investigated the impact of the Flint water crisis on American robin blood lead levels (BLL) during the breeding season in southeast MI by comparing BLL of birds captured at irrigated sites of Flint to those captured at unirrigated sites in Flint, irrigated sites in a nearby city (Ypsilanti) and rural sites. Robins captured at irrigated Flint sites had nearly double BLL compared to unirrigated Flint sites and all other control sites. Body condition declined with increasing BLL at these irrigated sites of Flint, suggesting a measurable fitness impact of lead at these levels. Because BLL in American robins is known to reflect soil lead levels and soil lead is a known driver of BLL in children, robins may act as a bioindicator for urban communities. Further research should determine the efficacy of using robin BLL as a bioindicator of soil lead and how lead might be impacting body condition and other long-term fitness metrics in urban wildlife.

Effect of Exterior Home Renovation on Community Lead Hazards: A Pilot Study in South Bend, Indiana

Communities across the US face challenges from legacy lead contamination. In South Bend, Indiana, over 68,000 homes were built before 1978, and most contain leaded paint. When these homes are repainted, repaired, or renovated, failure to use lead-safe practices can contaminate the surrounding soil with lead paint flakes and dust. In this study, we used X-ray fluorescence (XRF) to measure soil lead levels surrounding a home with exterior leaded paint (about 10% Pb w/w) after it was repainted in fall of 2019. The painted wooden exterior was prepared for painting by dry scraping without the use of tarps or plastic barriers. A total of 220 soil samples were collected from the home and its immediate neighbors, and an additional 102 samples were collected from 34 homes in the same neighborhood. The median lead level in dripline soil samples across the neighborhood was 434 ppm, but in the recently repainted house, the median soil lead was 1808.9 ppm, and it was 1,346.4 ppm in the four neighboring homes. The repainted house and its four neighbors were mulched by covering all bare soil to a 4-6 inch depth with chipped wood mulch. Two months later, another 100 soil samples were collected and analyzed. The surface lead level around the target house dropped to 13.8 ppm, showing that mulching is an effective strategy for interim control of high soil lead levels.