Any food in grease-resistant packaging
What do candy bars, microwave popcorn, stick butter, and fast food all have in common? Besides all being fatty and unhealthy, theyre all packaged in materials that are coated in a grease resistant chemical called perfluoro-octanoic acid (PFOA). Its also frequently used in stain resistant and water resistant coatings. PFOA is highly toxic, and once ingested, stays in your system for years. Even worse is microwaving foods in these kinds of packaging, because that can increase the process of chemicals leaching into your food.
Bottled and canned foods and beverages
The hard, clear plastics that are used in beverage bottles often contain bisphenol-A (BPA), and though most of it is excreted by the body, most Americans who have urine tests have traces of it in their systems. BPA can have estrogen-like effects, and can cause reproductive problems. Canned sodas and acidic vegetables like tomatoes are the worst offenders because their acidic nature will speed up the chemical leaching process.
Styrofoam cups and containers
Styrofoam food and beverage containers contain polystyrene, which has been known to leach into liquids in food- especially in the presence of heat, fats, acids, or alcohol. Polystyrene has been linked to nerve damage and cancer risk. Coffee, tea (especially with lemon, due to its acidity), hot chocolate, and alcoholic drinks are the worst to be consumed from styrofoam containers. Never microwave food in a styrofoam container, because again, this will increase the chances of chemical leaching.