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There's a trend that more city people decide that they want to grow crops and raise some live-stock (家禽). After all, there are few things more satisfying than biting into a bunch of tender, red carrots you grow yourself, or a fresh egg from the backyard.
Most gardeners understand that the soil in big cities is often polluted with lead and know to get their soil tested. But most are pretty clueless about how to prevent other types of pollutants, like heavy metals and asbestos(石棉)from getting into their vegetables.
Part of the problem is that “there might be pollutants that gardeners can't test for,” says Brent Kim, a program officer. Most soil tests look for lead, cadrniunt(镉)and arsenic(砷). But they don't test things like chemicals left behind by cars, which might have escaped into the soil.
So if you're thinking of staring an urban garden, Kim says, once you've found a plot of land, you should learn what's now an empty plot or a backyard might once have been a parking lot, a gas station or a chemical ground. “Knowing its past will give you some idea about what might be in that soil,” he says.
“People tend to think raised beds are going to solve their pollution problem,” Kim says. But polluted soil could easily kicked onto your plants, especially if the beds are low to the ground.
“Another consideration is that you have to be careful about the materials that you're using to build a raised bed,” Kim says. Recycling wood from an old construction site might seem like a good, eco-friendly idea. But that wood could be treated with chemicals you don't want touching your fruits and veggies, Kim says. And it's always a good idea to use gloves while gardening, and wash all your produce thoroughly.
“I see these urban growing spaces as these oases(绿洲)in the middle of these urban environments,” Kim says. “They bring communities together, and they help people save money on fresh produce. Urban growing spaces are amazing. Let's keep doing this, but let's do it safely.”
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