WHY IS THERE LEAD IN THE SOIL?
• Lead is found naturally in the soil in low amounts
• Most houses built before 1978 have leaded paint inside and outside
• Soil (mainly in large cities) may have high lead levels because of heavy industry and exhaust from leaded gas (banned in 1986)
WHERE CAN LEAD BE FOUND IN YOUR YARD?
• Lead may be found in the top 4 inches of soil around your yard
• Soil lead is found in highest amounts near the walls of buildings, especially if they were painted prior to 1978
• Soil lead levels can be higher close to roads
WHERE IS LEAD IN THE GARDEN?
• Lead is not usually found in the fruit of the plant like cucumbers, tomatoes, or strawberries
• Lead is most often found in the root of plants like carrots, beets, turnips, potatoes
• Soil with lead can collect on leafy vegetables (collards, kale, turnip greens) especially those close to the ground
WHEN SHOULD YOU BE WORRIED?
When your yard has a soil testing level of
• Below 100 ppm*: safe range, no action needed
• 100-400 ppm*: level of concern, use Best Gardening Practices
• 400-2,000 ppm*: NO gardening before contacting a professional gardening group like The Greening of Detroit
• Above 2000 ppm*: gardening of any kind is NOT recommended
* ppm = Parts-Per-Million = 1 milligram Pb per kilogram soil (mg/kg) (Concentration of Lead from soil test)
BEST GARDENING PRACTICES
• Treat soil with lead free compost
• Till soil as deeply as possible (at least 4 in.)
• Plant your garden away from buildings, garages and the street
• Keeping your soil pH above 6.5 will help limit the amount of lead entering plants
• Wear gloves and wash up after gardening
• Keep a layer of mulch around plants to stop soil from splashing onto leaves during rain
• Do not eat or smoke while gardening
• Wet the soil before working in the garden to keep soil dust down
• Keep children under 6 years old out of gardens with soil lead levels above 100 ppm* because they may eat dirt
After Harvesting/Before Eating
• Wash all vegetables with soap and water or a vinegar water mixture (1 part vinegar to 9 parts water)
• Throw away outer leaves of leafy vegetables, and wash inner leaves well
• Peel and wash root vegetables well (if your soil lead levels are higher than 400 ppm* you should not plant root crops before consulting a professional gardening group
CLEANING UP AFTER GARDENING
• Wash hands after working in the garden
• Remove shoes/boots before coming into your home
• Keep a separate set of clothes for gardening
• Wash gardening clothes separately
GET YOUR SOIL TESTED!
Contact Keep Growing Detroit at 313-757-2635 or visit detroitagriculture.net.
The above information was taken from the Lead Safe Gardening Pamphlet.
Download the pamphlet here: Lead Safe Gardening Pamphlet Download
Lead Poisoning 101 Brochure Sources and Additional Information:
Lead Contamination in Urban Gardens
Lead in the Home Garden and Urban Soil Environment