How to Recognize the Plastics That are Hazardous to You

Story at-a-glance

  • A classification system called the Resin Identification Code, which is the number printed on the bottom of most plastic bottles and food containers, describes what kind of plastic resin the product is made out of.
  • The most toxic plastics are #7, #3 and #6, while those that may be somewhat safer include #1, #2, #4 and #5.
  • Ninety-five percent of all plastic products tested were positive for estrogenic activity, meaning they contain chemicals that can potentially disrupt your hormones and cause other adverse health effects.
  • If at all possible, seek to purchase products that are not made from or packaged in plastic.


This is an older article that may not reflect Dr. Mercola’s current view on this topic. Use our search engine to find Dr. Mercola’s latest position on any health topic.

By Dr. Mercola

Look around your home and take note of just how many plastic items are around you.  From food containers and utensils to bags, water bottles, shower curtains and children's toys, plastic has become a permanent fixture in our everyday lives – but it's one that comes with serious consequences.

Approximately 200 billion pounds (that's 100 million tons) of plastic are produced every year. Some now say we have entered the "Age of Plastics."1 But all of these plastic chemicals are now finding their way into your body and the environment, where they are accumulating over time with potentially catastrophic biological consequences.

Why You Should Check the Resin Identification Code

It is possible to seriously cut back on the amount of plastic in your life, which I strongly recommend and give tips for below. However, for the plastics you do use it's important to be aware of the risks they pose.

This can be determined through a classification system called the Resin Identification Code, which is the number printed on the bottom of most plastic bottles and food containers. It describes what kind of plastic resin the product is made out of.

The featured article2 compiled a breakdown of what each Resin Identification Code means, which you can use to help you make informed decisions on your plastic usage. As you'll read below, you should generally avoid plastics labeled #7, #3 or #6, while those that may be somewhat safer include #1, #2, #4 and #5.

Getting to Know Your Plastics: What the 7 Numbers Mean

Plastic #1: Polyethylene Terephthalate (PET)

Typically used to make bottles for soft drinks, water, juice, mouthwash, sports drinks and containers for condiments like ketchup, salad dressing, jelly and jam, PET is considered safe, but it can actually leach the toxic metal antimony, which is used during its manufacture.

One study that looked at 63 brands of bottled water produced in Europe and Canada found concentrations of antimony that were more than 100 times the typical level found in clean groundwater (2 parts per trillion).3

It also found that the longer a bottle of water sits on a shelf -- in a grocery store or your refrigerator -- the greater the dose of antimony present. It is believed that the amount of antimony leeching from these PET bottles differs based on exposure to sunlight, higher temperatures, and varying pH levels.

Brominated compounds have also been found to leach into PET bottles.4 Bromine is known to act as a central nervous system depressant, and can trigger a number of psychological symptoms such as acute paranoia and other psychotic symptoms.

Plastic #2: High Density Polyethylene (HDPE)

HDPE, which is considered a low-hazard plastic, is often used for milk, water and juice bottles, as well as bottles for cleaning supplies and shampoo. It's also used to make grocery bags and cereal box liners. HDPE (like most plastics) has been found to release estrogenic chemicals.

In one study, 95 percent of all plastic products tested were positive for estrogenic activity, meaning they can potentially disrupt your hormones and even alter the structure of human cells, posing risks to infants and children.5 In this particular study, even products that claimed to be free of the common plastic toxicant bisphenol-A (BPA) still tested positive for other estrogenic chemicals.

Plastic #3: Polyvinyl Chloride (PVC)

PVC plastic can be rigid or flexible, and is commonly found in bags for bedding, shrink wrap, deli and meat wrap, plastic toys, table cloths and blister packs used to store medications.

PVC contains toxic chemicals including DEHP, a type of phthalate used as a plastics softener. Phthalates are one of the groups of "gender-bending" chemicals causing males of many species to become more female. These chemicals have disrupted the endocrine systems of wildlife, causing testicular cancer, genital deformations, low sperm counts and infertility in a number of species, including polar bears, deer, whales and otters, just to name a few.

Scientists believe phthalates are responsible for a similar pattern of adverse effects in humans as well. If your home contains soft, flexible plastic flooring, such as vinyl or those padded play-mat floors for kids (often used in day cares and kindergartens, too), there's a good chance it is also made from toxic PVC. PVC flooring has been linked to chronic diseases including allergies, asthma and autism.

Plastic #4: Low Density Polyethylene (LDPE)

Another plastic that is considered a low hazard, LDPE is used in bags for bread, newspapers, fresh produce, household garbage and frozen foods, as well as in paper milk cartons and hot and cold beverage cups. While LDPE does not contain BPA, it may pose risks of leaching estrogenic chemicals, similar to HDPE.

Plastic #5: Polypropylene (PP)

PP plastic is used to make containers for yogurt, deli foods, medications and takeout meals. While polypropylene is said to have a high heat tolerance making it unlikely to leach chemicals, at least one study found that PP plastic ware used for laboratory studies did leach at least two chemicals.6

Plastic #6: Polystyrene (PS)

Polystyrene, also known as Styrofoam, is used to make cups, plates, bowls, take-out containers, meat trays and more. Polystyrene is known to leach styrene,7 which can damage your nervous system and is linked to cancer, into your food. Temperature has been found to play a role in how much styrene leaches from polystyrene containers, which means using them for hot foods and beverages (such as hot coffee in a polystyrene cup) may be worst of all.

Plastic #7: Other

This is a catch-all designation used to describe products made from other plastic resins not described above, or those made from a combination of plastics. It's difficult to know for sure what types of toxins may be in #7 plastics, but there's a good chance it often contains BPA or the new, equally concerning chemical on the block in the bisphenol class known as Bisphenol-S (BPS).

BPA and BPS are endocrine disrupters, which means they mimic or interfere with your body's hormones and "disrupts" your endocrine system. The glands of your endocrine system and the hormones they release are instrumental in regulating mood, growth and development, tissue function, metabolism, as well as sexual function and reproductive processes.

Some of the greatest concern surrounds early-life, in utero exposure to bisphenol compounds, which can lead to chromosomal errors in your developing fetus, causing spontaneous miscarriages and genetic damage. But evidence is also very strong showing these chemicals are influencing adults and children, too, and leading to decreased sperm quality, early puberty, stimulation of mammary gland development, disrupted reproductive cycles and ovarian dysfunction, cancer and heart disease, among numerous other health problems.

For instance, research has found that "higher BPA exposure is associated with general and central obesity in the general adult population of the United States,"8 while another study found that BPA is associated not only with generalized and abdominal obesity, but also with insulin resistance, which is an underlying factor in many chronic diseases.9

Plastics Pose a Great Risk to the Environment, Too

Plastics are not only an issue in products while they're being used but also when they're disposed of. While approximately 50 percent of plastic waste goes to landfills (where it will sit for hundreds of years due to limited oxygen and lack of microorganisms to break it down) the remaining 45 plus percent "disappears" into the environment where it ultimately washes out to sea, damaging marine ecosystems and entering the food chain.

Plastic particles are like "sponges" for waterborne contaminants such as PCBs, pesticides like DDT, herbicides, PAHs, and other persistent organic pollutants. This phenomenon makes plastics far from benign, and scientists have yet to determine the full extent of the dangers posed by their consumption or the effects higher up the food chain.

One of the biggest environmental assaults is the massive accumulation of plastic trash in each of the world's five major oceanic gyres. Gyres are large, slowly rotating oceanic whirlpools, driven by global winds and ocean currents.10 Garbage and debris is funneled into the center of these gyres, in a kind of toilet bowl effect or vortex.

One of these gyres, the North Pacific Gyre, is in the middle of the Pacific Ocean about a thousand miles from the Western coast. In its midst is a huge mass of trash (90 percent plastics), which floats in a soup of smaller pieces that have been broken apart by wave action.

Some call it the "Great Pacific Garbage Patch" and others the "Pacific Trash Vortex," but regardless of its name, it's the largest "landfill" in the world. In it you will find everything from plastic netting to bottles and bags and buckets, paint rollers, hula-hoops and medical equipment. Most of the garbage patch, however, is not made up of large items but rather microplastics you can't see with the naked eye, forming a sort of plastic soup where pure seawater used to be. Filter-feeding marine animals ingest these plastic particles, and the toxins they contain, and subsequently pass them up through the food chain, and eventually to humans.

Tips for Cutting Down on Your Plastic Use

If at all possible, seek to purchase products that are not made from or packaged in plastic. Here are a few ideas for doing so:

Use reusable shopping bags for groceries Bring your own mug for coffee Bring drinking water from home in glass water bottles, instead of buying bottled water
Store foods in the freezer in glass mason jars as opposed to plastic bags Take your own non-plastic container to restaurants for leftovers Request no plastic wrap on your newspaper and dry cleaning
Avoid disposable utensils Buy foods in bulk when you can Replace your plastic kitchenware with glass or ceramic alternatives
Use stainless steel or high-heat-resistant nylon for utensils in lieu of plastics    


Since plastic is found widely in processed food packaging (this includes canned foods and beverages, which typically have a plastic lining), modifying your diet to include primarily fresh, whole foods that you purchase at a farmer's market or food co-op will have the added benefit of helping you cut down on exposure to plastic chemicals that are common in the food packages sold at most supermarkets.


By continuing to browse our site you agree to our use of cookies, revised Privacy Policy and Terms of Service.