UC HEALTH LINE: Sun Isn t the Only Consideration for Urban Gardening

CINCINNATI—The benefits of gardening go beyond reaping the fruits (or vegetables) of your labors … gardening is a source of exercise, financial savings and pride. 

As more urbanites test their green thumbs, experts caution growers to think beyond the sun/shade balance: The legacy of lead-based paint and gasoline still exists today in unexpected places like the soil in your own back yard.  

"Lead is an element which doesn’t break down over time and it is difficult to remove once it is in the environment or our bodies,” explains Bill Menrath, a senior research associate with the UC College of Medicine’s environmental health department.  "People think they are only exposed to lead through lead-based paint, but exposure sources exist throughout our environment.” 

Menrath says this isn’t a reason to restrict gardening to rural farms; but if someone lives in a pre-1978 house it is important to take precautions when working in the yard—especially for households with small children. 

He recommends following these simple steps to create a safe urban garden for your family to enjoy together:

• Plant your garden at least 10 to 15 feet from old buildings and from roads.This will reduce the risk of exposure from flaking lead-based paint that has fallen to the ground and been absorbed into the soil, either recently or in the past. Areas farther from the road may also have lower lead concentrations related to gasoline exhaust from leaded gasoline days.

• Build a raised bed or use above-ground containers. Most soil around older buildings has some level of lead contamination. To avoid the risk entirely, consider installing a simple rectangular bed above the existing ground filled with 6 to 8 inches of clean soil and organic material, like manure or peat moss. Vegetable roots are shallow, so there is less risk that they will reach the contaminated soil. 

• Chose low-risk crops.Plants grown in lead-contaminated soil can become contaminated with lead  so root vegetables like carrots, beets, onions, potatoes and similar crops are of the most concern. Leafy vegetables can also be risky because fine dirt particles can splash up on the leaves and are unintentionally eaten. Tomatoes, peppers, beans and other above-ground non-leafy vegetables are the best options for urban gardening. 

• Wash and scrub those veggies.Menrath says thoroughly washing all your vegetables, especially the root crops, with a mild vinegar and water solution before eating them is critical. You can use a stiff brush to scrub root vegetables. Lead often concentrates on the skin of the vegetable, so peeling root vegetables can reduce lead ingestion risk as well.

Outside of the garden, Cincinnati Children’s Hospital Medical Center pediatrician Nick Newman, DO, there are three simple steps every family should follow to reduce the risk for lead exposure: Wash your hands regularly–especially before eating; remediate chipping paint in and outside the home; and remove your shoes to avoid tracking potential lead-contaminated dust inside. 

"Children absorb about 50 percent of the lead they ingest and their natural hand-to-mouth-behaviors put them at even greater risk for exposure,” adds Newman, who serves as director of the Pediatric Environmental Health and Lead Clinic at Cincinnati Children’s. "Public health initiatives have made great strides in reducing the number of lead poisoned children, but it still happens and the health effects are irreversible.  

Previous UC research led by Kim Dietrich, PhD, has shown that childhood lead exposure negatively impacts cognitive and neuromotor (muscle-function) development and may even cause irritability and aggressive behavior that leads to increased criminal behavior in adulthood. Inhalation and digestion of lead-laced dust particles are the most common means of exposure. 

Learn more about preventing lead poisoning in children from the Ohio Department of Health.