Research & reports

Carithers, Jaci, Gowen, Samantha, Jenney, Francis · Digital Commons - PCOM (Philadelphia College of Osteopathic Medicine) · United States (Atlanta)

A study in a Metro Atlanta residence, United States, analyzed lead contamination in soil and plant samples using inductively coupled plasma mass spectrometry (ICP-MS). The research found substantial lead contamination, particularly in areas where crops were grown. Results demonstrated the propagation of lead from contaminated soil into local vegetation over time, with an average level of 143.9 mg/kg, ranging from 5.1 mg/kg to 499.5 mg/kg.

U.S. Environmental Protection Agency · U.S. Environmental Protection Agency (EPA) · United States

This EPA page (last updated December 22, 2025) explains chromated copper arsenate (CCA), a wood preservative used since the 1940s for utility poles, posts, and other structural lumber. Manufacturers voluntarily ended CCA use for residential wood products in December 2003. EPA notes cancer and non-cancer health risks for workers and environmental risks to aquatic invertebrates and plants, while stating there is no health risk to the general public; removal of existing CCA structures is not mandated, though periodic sealant coating is recommended to reduce leaching.

Zhongqi Cheng, Anna Paltseva, Ireyena Li, Tatiana Morin, Hermine Huot, Sara Perl Egendorf, Zulema Su, Roxanne Yolanda, Kishan Singh, Leda Lee, Michael Grinshtein, Ying Liu, Kayo Green, Win Wai, Bushra Wazed, Richard K. Shaw · Soil Science · United States (New York City)

This study analyzed trace metal concentrations (Cr, Co, Ni, Cu, Zn, As, Cd, Pb) in 1,652 soil samples from 904 gardens in New York City. It found that many soils exceeded New York State Department of Environmental Conservation's Soil Cleanup Objective (SCO) limits for Pb, Cr, As, and Cd. Specifically, about 21% of community garden samples and 71% of home garden samples exceeded SCO limits for Pb and As, and less than 3% of all samples met criteria for unrestricted use.

David R. Koenig · BIOS · United States (Sacramento)

This research project, conducted at the University of California, Davis, aims to understand how elevated soil lead levels may affect urban gardening activities in Sacramento, CA. The study investigates the distribution of soil lead levels in the city and how knowledge of this information impacts the local community. Elevated soil lead levels are identified as a potential barrier to urban gardening.