Buying organic is a good way to cut your exposure to potentially harmful pesticides, but it can get expensive. So how can you save on organics?

According to the September issue of ShopSmart magazine, one way to save is to limit organic purchases to fruits and veggies that have the most dangerous pesticide residues when grown conventionally.

Here are the worst of the bunch, in order of risk, based on a new analysis of government data by the nonprofit Organic Center. (Produce with the lowest pesticide risk includes citrus fruits, bananas, pineapples and onions.)

Riskiest fruits: imported grapes, cranberries, nectarines, peaches, strawberries, pears, apples and cherries.

Riskiest vegetables: green beans, sweet bell peppers, celery, cucumbers, potatoes, tomatoes, peas and lettuce.

This list refers to U.S. produce. Some imported items have higher pesticide levels. The “risk index score” for an imported peach is almost 5 times that of a domestic peach; for sweet bell peppers, it’s nearly 5 1/2 times as high. Also, be wary of overseas “organics,” where regulatory oversight might not be as reliable.