Cindy Fox Aisen
Not since victory gardens helped World War II era Americans on the home front survive food shortages have urban gardens been as necessary and popular as they are today. With more food production in cities, the safety of the produce grown there becomes increasingly important.
As city dwellers across the country are harvesting fruits and vegetables for family consumption and planning ahead for the next planting season, geochemist Gabriel Filippelli, Ph.D., professor of earth sciences at the School of Science at Indiana University-Purdue University Indianapolis, warns that urban soil may be contaminated with lead. He advises investigating the legacy of contamination in soil before planting and eating.
“Most surface contamination in urban settings like Baltimore, Brooklyn, Detroit or Indianapolis is from harmful metals, especially lead, and tends to be found near roadways, older homes or lead smelters. Sources of contamination can be automobile exhaust, degraded paint, tire and vehicle debris, industrial emissions or other products of human technology,” said Filippelli, who is an international leader in the emerging field of medical geology.
He encourages urban gardeners to study a map of their metropolitan area and determine potential soil contamination risk by proximity to busy streets, major roadways, freeways, dilapidated painted structures or older industrial facilities.
Gardens with no or low levels of lead contamination as determined by location or with test results of less than 200 parts per million (ppm) can be abundantly planted, but may benefit from high phosphate fertilizer which immobilizes metals like lead.
For gardens at medium risk based on location or soil tested at 200-500 ppm, he recommends covering the soil, planting in raised bed settings, and mulching between beds to reduce the risks of tracking lead-rich soil onto the plots or into the home.
Read full post at Science Daily