密歇根新闻广播 含铅的水浇菜园有问题吗?（在线收听）

Drinking lead-tainted water is out of the question, as is cooking with it and bathing in it. But what about gardening? Is it safe to water your garden with leaded water through a hose without a filter?

Below is Teresa McLean's answer. She's a Flint-based Michigan State University Extension Service educator in community food systems.

McLean said you will not be "appreciably adding" to lead in soil by watering it with lead-tainted water. But that doesn't mean lead in soil isn't a concern.

Lead already exists in some soils across Michigan. McLean said it occurs naturally at low levels, but it also comes from other places—like lead paint on houses and lead remnants from when cars used lead gasoline.

For that reason, McLean said it's crucial to test for lead in soil before you garden. The EPA's Hazard Standard for lead in soil says any lead level below 400 parts per million is safe—and that's in areas where children play. McLean, however, suggests a 300 ppm limit.

The good news about veggies

When it comes to growing food, even in soil that contains lead, McLean had some good news.

"Fortunately for us, vegetables are not very good at taking up lead," she said. "When we talk about low-risk vegetables, anything that fruits … like tomatoes, peppers, green beans, corn—if there is any lead uptake at all, it does not get translocated to the fruits, and so those are considered the safest type of vegetable to grow in a garden with elevated lead levels."

While lead doesn't typically make its way into vegetables, it can stick to them. That's why McLean said gardeners should be wary of "soil splash."

"Soil splash, the soil that gets stuck to our root vegetables or our leafy greens, could be a concern if not washed properly," she said. "And so we do recommend peeling all root crops and pulling off the outer leafy greens. Of course, here in Flint, we have to wash them thoroughly with filtered or bottled water."

McLean also suggested that people gardening in soils with elevated lead levels wear gloves and boots when gardening to prevent unnecessary contact with lead.