Response: Microwave ovens cook food using microwave radiation (at a frequency of 2450 mHz), which is also used by mobile phones, TV broadcasting, and radar systems. Microwave radiation differs from radiation produced from the sun or X-rays, in that it is non-ionizing and thus non-cancer causing. Nevertheless, the use of microwave radiation to cook food has raised some concerns about microwave ovens, generally because of possible radiation leaks, nutrient loss, and the possibility of cancer causing food byproducts.
Standing in front of your microwave may increase your exposures to microwave radiation; however, such increases are likely to be low, especially when compared to your exposures to microwave radiation from your cell phone. Exposures to microwave radiation are kept low by the oven design, which makes sure that microwaves stay inside the oven and are only produced when the oven is on and the door is shut. Radiation leaks around and through the glass door are generally below levels recommended by international standards.In the United States, microwave ovens are regulated by the US Food and Drug Administration, who set safety requirements for new microwave ovens of 1 mW/cm2, measured 5 cm away from the oven surface. [This requirement sets the rate of energy flow per unit energy.] The maximum permissible radiation level is higher for older microwave ovens, with an allowable level of 5 mW/cm2, measured 5 cm away from the oven surface. Both levels are thought to be safe and to pose no risk to your health.
You should be aware, however, that your oven could leak more microwave radiation, if it gets damaged, is dirty, or is improperly operated or maintained. You can minimize these chances by making sure that your oven door closes properly and that your door’s safety devices (that prevent microwaves from being produced when the door is open) work correctly. Also, you should make sure that the seals to your door and oven are clean and intact. If your oven is damaged in any way, you should not use it until it has been repaired by an appropriately qualified service engineer.
If you are still worried or want to be cautious, you can also just watch your food cook from further away. This will reduce your exposures to radiation from your microwave substantially. Happy cooking!
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Helen Suh MacIntosh is a professor in environmental health at Harvard University and studies how pollution behaves in the environment and how it affects people's health. Please keep in mind that her answers are just her interpretation of available information and should not be taken as the only viewpoint or solution to a problem. Use this column at your own risk. Having said this, please feel free to post any of your environmental health questions to AskTreeHugger [[@]] TreeHugger [[.]] com (please use a descriptive email subject line and mention if you want to remain anonymous or not).