You skip the pesticides, you remove weeds by hand, you choose heirloom seeds. Organic methods give you comfort in knowing that your vegetables are grown without excessive chemicals.

But what many careful gardeners don’t know is their gardens can carry a hazard that organic methods alone may not prevent: lead.

Lead has no safe level of exposure and it’s present in the soil of some Canadian urban gardens. Where does it come from? Leaded gasoline emissions from historical use, deteriorating lead-based paint that seeps into the soil around older buildings and industrial activities like mining.

Luckily there are many simple and affordable ways to reduce lead exposure and make our gardens safer.

Lead affects us all differently

Lead has no function in the human body and is harmful in any concentration.

Though estimates vary, adults absorb around three to 10 per cent of the lead they ingest, while those who are fasting or malnourished may absorb up to 60 to 80 per cent. The number is higher for children, who may absorb up to 50 per cent — or up to 100 per cent on an empty stomach.

For adults, lead accumulates primarily in our bones and teeth due to repeated or prolonged exposure before slowly being released into the rest of the body. For children, a greater proportion of lead is absorbed in soft tissues, causing serious health problems to begin earlier in life.

Over time, exposure can cause long-term irreversible health effects on the brain and nervous system, the kidneys and the........

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