Dear Co-op America,
I have heard that plastics leach chemicals into our food and water when we use them. Is this true?
– Jane G., E-mail

It is true, Jane. Plastic can leach chemicals throughout its lifecycle. Toxins such as benzene and dioxin are released into surrounding communities during the manufacture of certain types of plastic, and some types leach chemicals as we use them. In addition, several studies have uncovered health risks associated with exposure to fumes when incinerating plastic. Of most concern to your health and the environment are the types of plastic coded for recycling as numbers three, six and seven.

Number three plastic: Polyvinyl chloride (PVC) production requires highly polluting and carcinogenic chemicals that can contaminate the surrounding environment. PVC often is made with softeners such as phthalates, which can leach out of or evaporate from the finished products and have been shown to cause developmental and reproductive damage. PVC incineration leads to the emission of dioxins, which are known to cause cancer, as well as reproductive, developmental and immune problems. Dumping PVC in landfills can cause the plastic's toxic additives to leach into groundwater.

Number six plastic: Polystyrene is a concern because the chemical styrene can leach from it into food and beverages. According to the EPA, short-term styrene exposure at levels above the Maximum Contaminant Level (used to set drinking-water standards) can cause nervous-system effects such as loss of concentration, weakness and nausea. Long-term exposure can cause liver and nerve damage and cancer.

Number seven plastic: Although the “number seven” designation is a catch all for plastics that do not fit into the other categories, products marked with this number are often polycarbonates, which are used in plastic baby bottles, the liners of metal food cans, sport water bottles and other items. Bisphenol-A (BPA) is an endocrine disruptor that can leach from polycarbonates when they are used. More than 80 percent of published studies assessing the effects of low-dose BPA exposure on laboratory animals found significant effects including alterations to brain chemistry, behavior, the immune system and male and female reproductive systems.

When you do use plastic, it is best to avoid those labeled with numbers three, six and seven. However, there are still chemical-leaching concerns associated with any plastic. To avoid chemical leaching, do not use plastic containers or cling wrap to heat food in the microwave and avoid bottled water, if possible. If you do drink bottled water, try not to buy bottles that have been stored for a long time or those that have been scratched. Do not reuse single-use water bottles. Do not use polycarbonate water bottles with warm or hot liquids. Avoid plastic toys if your children are still putting toys in their mouths. And avoid polycarbonate baby bottles.

Dear Co-op America,
I'm on a budget, so I need to know what types of produce do I absolutely need to buy organic to avoid toxins?
– Fred A., Los Angeles, CA

According to the Organic Consumers Association, produce with the highest pesticide levels are: apples, bell peppers, celery, cherries, imported grapes, nectarines, peaches, pears, potatoes, red raspberries, spinach and strawberries. We recommend buying these organic. Produce with the lowest pesticide levels include: asparagus, avocados, bananas, broccoli, cauliflower, sweet corn, kiwi, mangoes, onions, papaya, pineapples and sweet peas.

“Living Green” is brought to you by Co-op America, a national nonprofit that provides green living, purchasing and investing tips and resources. To join Co-op America and get a free copy of the National Green Pages™ directory of green businesses, call (800) 58-GREEN or visit www.coopamerica.org. E-mail Living Green questions to livinggreen@coopamerica.org.