Organic vegetables are wonderful, and well worth their price, say some. Growing your own organic vegetables is best, of course. You feel safer knowing exactly what was used on your vegetables before they got to your table. But if you cannot grow your own organic vegetables, the argument goes, it is worth the trouble to find a store or farmers' market where you can buy them. So let's suppose you take that trouble. Let's suppose you find a source of organic vegetables.

Do you know what vegetables to buy organic? Are all organic vegetables worth the higher price?

Organic vegetables that are certified organic under U.S. Dept. of Agriculture regulations must be produced without most synthetic pesticides, synthetic fertilizers, antibiotics, growth hormones, and feed made from animal parts.

Organic certification sounds like something most of us would want, but is it always necessary? Is it worth the extra money?

What Vegetables to Buy Organic

These 5 organic vegetables are usually worth the higher prices, since conventionally grown versions contain high amounts of pesticide residues.

1. Green beans: Conventionally grown green Beans can contain three organophosphates that are toxic to the nervous system: acephate, dimethoate and methamidophos. They can also contain endosulfan, an insecticide that disrupts endocrine secretion.

2. Potatoes: Non-organic potatoes are increasingly being exposed to pesticides, according to the Consumers Union. These potatoes may contain dieldrin and methamidophos. While this is bad enough for adults, children who eat potatoes are at risk for a high dose of aldicarb, a pesticide that pervades the inside of the potato.

3. Spinach: Spinach is ahead of all foods when it comes to DDT. Other pesticide residues are claimed to be falling as U.S. farmers are learning to use less quantities of synthetic insecticides. Nevertheless, spinach still can contain permethrin and dimethoate. Permethrin is thought to be potentially cancer-causing.

4. Tomatoes: Tomatoes grown by conventional means have been found high in chlorpyrifos. Chlorpyrifos, also known as Lorsban for farm use and Dursban for home use, is the most heavily used insecticide in the United States.

5. Winter Squash: When tested, two-thirds of winter squash samples exceeded the safe daily limit for a young child of Dieldrin, a chlorinated, carcinogenic insecticide. Heptachlor, another powerful carcinogen was also found. Winter squash in baby food contained DDT.

What Fruits to Buy Organic

Organic vegetables are only part of the picture when it comes to produce. Organic vegetables are often peeled and cooked before eating. Organic fruits are often eaten unpeeled, especially by young children. Young children also consume much greater amounts of fresh fruit per pound of body weight than do adults. The pesticides are concentrated more highly in children.

So while you're thinking about what vegetables to buy organic, you should also consider these 7 fruits.

1. Apples: Apples can contain methyl parathion. Whether fresh apples, applesauce, or baby food, they can also contain chlorpyrifos.

2. Cantaloupe: Like tomatoes, cantaloupes grown by conventional means have been found high in chlorpyrifos.

3. Grapes: Imported grapes can contain dimethoate. Grapes grown in the U.S. contain methomyl and methyl parathion. Methomyl is a carbamate insecticide listed as an endocrine disruptor.

4. Peaches: Peaches are perhaps the worst of all fruits when grown conventionally. They contain high amounts of iprodione residue, classified by the Environmental Protection Agency (EPA) as a probable human carcinogen. Peaches also contain methyl parathion, an organophosphate insecticide.

5. Pears: All conventionally grown pears, whether fresh or in baby food, can contain methyl parathion, as well as other insecticide residues.

6. Raspberries: Organic raspberries may be expensive, but you will be avoiding the fungicide captan, iprodione and carbaryl.

7. Strawberries: If you go for the beautiful red color of conventionally grown strawberries, you should know that it is caused by the fungicide captan, believed to be a possible human.

What Organic Vegetables Should You Buy?

Some organic vegetables are probably not worth the extra cost. When organic vegetables and fruits pose a health risk high enough to be listed by Consumers Union, however, you may want to take notice.