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Are you eating cancer?

PETERSON AIR FORCE BASE, Colo. -- If it doesn't clearly say "microwave-safe", it probably isn't.

According to the National Sanitation Foundation International webpage, placing certain plastics into the microwave can be harmful to your health.

Many white paper towels are fabricated with plastics, and are not microwave safe. Even some paper plates can be harmful. Plain paper is safe, but plastic coated paper is generally not microwave-safe.

The NSF is a World Health Organization recognized for its scientific and technical expertise in the health and environmental sciences and recommends never using plastic storage containers such as margarine tubs, take-out containers, whipped topping bowls and other one-time use containers for cooking or reheating food in your microwave. These containers are not heat resistant and can melt, possibly leaching harmful chemicals into your food. When eaten, these chemicals can disrupt the endocrine system, increasing risk for certain cancers, diabetes and early puberty, according to the NSF.

To minimize risk, the NSF also recommends using non-plastic dishes in the microwave; glass and ceramic are preferred for use in a microwave oven. When that's not possible, only use microwave-safe plastics.

How do you know? Check the triangle.

Just what is in a triangle? On the bottom of most plastic containers, you will find a small triangle made of arrows with a number inside of it. This number indicates the type of plastic that the product is made out of. By understanding this number, consumers can better understand if and how they can recycle the product and more importantly if it is safe to place in the microwave.

Plastics marked with a "Type 1" are the easiest to recycle and are in high demand by re-manufacturers. This plastic is widely accepted by recycling facilities and curbside recycling programs. These plastics are made of polyethylene terephthalate, also known as PETE or PET. Some common plastics marked with a number one include soda and water bottles, some medicine containers, mouthwash bottles, peanut butter containers, salad dressing bottles and vegetable oil containers.

Type 1 and Type 2, which contain mostly high density polyethylene (HDPE), may be safe if marked "microwave safe"; however, some recommend against food contact when microwaving.

Type 5 plastics contain polypropylene (PP) and are used to make food storage containers like ketchup and syrup bottles, straws and plastic bottle caps. This type of plastic is most commonly labeled "microwave safe" although some still recommend against food contact when microwaving.

Polypropylene, which is in Type 5, is difficult to recycle and is only occasionally accepted through curbside programs and recycling centers.

However, as new methods for recycling PP are becoming more common, an increased number of recycling centers are accepting it.

Type 7 plastics are the most difficult to recycle and should never be used in the microwave. Some of these plastics are uniquely recycled by artists who find ways to fashion the materials into new objects. This plastic can also occasionally be re-manufactured into plastic lumber. It is important to know that some nursing bottles contain Polycarbonate and should be thrown out if they have been boiled or washed more than 20 times or are badly scratched.

What about items such as coffee cups, disposable cutlery and plates, meat trays, packing peanuts, insulation, egg cartons and carryout containers? These are Type 6 plastics made from polystyrene (PS), also known as Styrofoam. They are not heat stable and are a potential human carcinogen, meaning they contain bisphenol A (BPA), and they should never be microwaved.

Type 6 plastics are difficult to recycle, but are sometimes accepted by recycling plants and curbside programs.

Type 3 plastics are also difficult to recycle and contain polyvinyl chloride (PVC). Vinyl, a Type 3 material, often contains bisphenol A (BPA) making it hard to recycle.

Type 3 plastics are used for some plastic wraps and they should never be used in a microwave with food. PVC is also used in shower curtains, baby bottle nipples and a variety of clear bottles and packaging products. Recycled PVC can be used to make decks, mud flaps, gutters, flooring and cables.

Simply knowing the meaning of the plastic type can not only help the environment but also your body. Check with your local recycling facilities and Civil Engineering squadron to find out more on the harm plastics can cause and the proper way to dispose of them.