In honor of Plastic Free July, I thought I’d talk about some of the dangers of plastics, plus how to start avoiding them. From food storage containers and utensils to water bottles and toys, plastic has become so huge it’s spread to practically every part of our lives. Over 300 million metric tons of plastic are produced each year, and the toxic chemicals that go along with it are finding their way into your body and the environment, where they are collecting over time with some alarming results.
Plastics contain chemicals that are linked to tons of health concerns, cancer and reproductive issues for example. They usually contain endocrine disruptors, which is a huge part of why they’re so dangerous. Some chemicals used in plastic include BPA, polybrominated diphenyl ethers (PBDE), and phthalates. These kinds of harmful chemicals can enter the body through ingestion, inhalation, and absorption. One way plastic can be ingested is through leaching, or when chemicals from the plastic transfer into whatever’s around it, such as food, beverages, and items inside plastic packaging, or surrounding land and water. This effect is amplified when heat is involved, such as when hot food or beverages are placed in plastic containers, food is microwaved on a plastic plate, or plastic water bottles are cleaned in a dishwasher. Plastic toxins can also pass into the body directly, through microplastics. Microplastics, though somewhat self-explanatory, are tiny (specifically, <5 mm) pieces of plastic. There are two categories, primary and secondary. Primary microplastics are made to be used in cosmetics, synthetic fabrics like polyester and nylon, and fishing nets, among other things. The small size of plastic microbeads in facial scrubs, toothpaste, and body washes allows them to enter the body even more easily (try the Beat the Microbead app to check your beauty products!). Secondary microplastics come from large plastic items, such as children’s toys, plastic packaging, and water bottles, breaking down into smaller pieces due to sun radiation and waves. Plastic can’t decompose, so these microplastics will continue to harm humans and animals for millions of years. Microplastics wash out into the oceans and are absorbed by small organisms like plankton or eaten by bigger animals, which travel up the food chain, so humans end up eating them (they’ve been found in seafood). Unfortunately, there is no source of seafood that has no microplastics. Microplastics are even in drinking water, and water treatment facilities can’t remove them. Studies show that people are ingesting and breathing in about 5 grams of microplastics each week - that’s the same as eating a credit card once a week! Microplastics have been found in the digestive system and feces (and scientists think that may harm our bodies’ ability to destroy germs when they enter the stomach), the lungs, babies, fetuses and placentas (exposing them to cell-, organ-, and DNA-altering chemicals at some of the most critical stages of development and putting them at risk of damage to the reproductive system and other organs, cancer, and disease), and recently, human blood, which allows the microplastics to travel to all parts of the body. In studies on mice, microplastics were found in every tested organ of the body (including the brain) after exposure through water. Behavioral changes occurred, and levels of one kind of protein decreased, which can lead to Alzheimer's and depression, among other neurological concerns. Some other examples of plastic entering the body are breathing in the air from around plastic items filled with VOCs, or volatile organic compounds (make sure you let these items off-gas, or release toxic fumes, outdoors), and applying lotion that was kept in a plastic container.
Plastics are not only an issue in products while they're being used, but also when they're disposed of. About 50% of plastic goes to landfills (where it will sit for millions of years, leaching chemicals and releasing microplastics, or be burned, releasing toxic fumes). The rest washes out to sea, damaging marine ecosystems and entering the food chain, plus plastic particles absorb waterborne toxins such as PCBs, pesticides, herbicides, and PAHs, meaning those enter the food chain too. One of the biggest environmental problems is the huge buildup of plastic garbage in the five main ocean gyres. Ocean gyres are whirlpools made by global wind patterns and currents created by Earth’s rotation. The North Pacific Gyre is the biggest “landfill” on the planet, located in the center of the Pacific Ocean around a thousand miles off the West Coast of the US. 90% of the swirling trash is plastic, and as the ocean currents break down the items, animals mistake the smaller pieces for food. The seawater in the gyre is now filled with microplastics too, contaminating the once-pure ocean with carcinogenic chemicals and endocrine disruptors. The plastics then sink deeper into the ocean, allowing the toxins to be easily spread throughout all the water in the world by deep ocean currents and animals. This results in humans consuming microplastics either by drinking water, or eating seafood or even produce that was irrigated with polluted water.
The Resin Identification Code, the number inside a recycling symbol printed on the bottom of most plastic objects, is a classification system that tells you what type of plastic you’re dealing with, and therefore, what health risks are associated with it. The most toxic plastics are #7, #3, and #6. Here are the different types!
Plastic #1: Polyethylene Terephthalate (PET/PETE):
PET is commonly used to make bottles for soft drinks, water, juice, mouthwash, and condiments, as well as synthetic fabrics like polyester and chewing gum. It leaches the toxic metal antimony, which is used in its production. Antimony harms the eyes, skin, lungs, heart, and stomach, and it is a carcinogen and endocrine disruptor. One study found that the longer a water bottle sits, like in a grocery store or fridge, the more antimony is in the water. Sunlight, heat, and lower pH levels can also increase the amount of antimony leached. Antimony has also been found in fabrics, like polyester blends, that are made of PET. Bromine, which is known to act as a central nervous system depressant and can trigger a number of mental illnesses, also leaches from PET. Exposure to UV rays as well as heat can increase this leaching. PET has been found to contain endocrine disruptors, especially phthalates (which can increase obesity and insulin resistance, decrease anogenital distance in males, decrease levels of sex hormones, and harm both female and male reproductive systems, among other health concerns – fetuses, babies, and children are especially vulnerable). PET contains carcinogens too. One study found that water in a PET bottle triggered a 78% rise in the growth of breast cancer cells compared to the control water. Don’t reuse PET, like a disposable plastic water bottle for example, as PET leaches a greater amount every time it is reused.
Plastic #2: High Density Polyethylene (HDPE)
HDPE is used to make items such as milk, water, cleaning supply, shampoo, and juice bottles, grocery bags, cereal box liners, picnic tables, and tableware. It can leach estrogenic chemicals (endocrine disruptors that mimic or interfere with estrogen) that are particularly dangerous to fetuses and teens. HDPE is produced with chromium oxide, which causes respiratory issues, such as asthma and bronchitis. Some of the other effects linked to HDPE are included in the LDPE section below, as the research is for both kinds of polyethylene. If using plastic is unavoidable, HDPE is a good choice as it’s one of the less harmful plastics. It’s also worth noting that there is very little research on HDPE alone, so we may be unaware of other HDPE-specific risks.
Plastic #3: Polyvinyl Chloride (PVC)
PVC can be stiff or flexible, and is commonly found in piping, bags for bedding, credit cards, shrink wrap, clothing, electronics, kitchen appliances, deli wrapping, toys, and tablecloths. Vinyl flooring and children’s playmats are also likely made from PVC. It’s the most dangerous plastic, so much so that it’s called the “poison plastic”, yet it’s also the third most common plastic in the world. PVC is full of endocrine disruptors, carcinogens, BPA, lead, mercury, phthalates, and many other toxic chemicals, including DEHP, a plastic-softening phthalate known to cause cancer. PVC causes cancer, genital deformations, low sperm count, and infertility in humans and animals. Several studies have shown that exposure to phthalates like in PVC causes short anogenital distance (more similar to females) which is directly linked to low sperm count, called phthalate syndrome. Exposure to PVC can alter ovarian structure, cause it to take longer to get pregnant, and increase the number of males being born. Some other health concerns linked to PVC are hormone disruption (which results in a multitude of other problems, especially reproductive ones, that you can read about here), allergies, asthma, autism, nausea, liver, brain, and reproductive damage, developmental issues in children, birth defects, scleroderma (the hardening and tightening of the skin that might also affect blood vessels, internal organs, muscles, and the digestive tract), endometriosis, immune system issues, respiratory system dysfunction, lymphohematopoietic system damage, and eye, nose, and lung irritation. When produced, used, or burned, like in landfills, PVC releases hydrogen chloride, a corrosive, extremely toxic gas that can burn skin and cause permanent respiratory damage, and dioxin, the world’s most dangerous and incredibly persistent synthetic carcinogen. The primary source of the global dioxin burden is PVC.
Plastic #4: Low Density Polyethylene (LDPE)
LDPE is used in bread, newspaper, ziploc, frozen food, garbage, and produce bags, as well as paper milk cartons, cups for both hot and cold drinks, and plastic wrap. LDPE poses risks of leaching estrogenic chemicals, similar to HDPE. LDPE, also like HDPE, is made with chromium oxide. Polyethylene (LDPE and HDPE) microplastics have been shown to alter DNA and harm cells. Polyethylene additives (similar to many plastics' additives) have been linked to issues like reproductive harm and cancer. One study showed that LDPE and HDPE microplastics can change the kinds of bacteria in the digestive system and cause inflammation. Like HDPE, if you can’t avoid using plastic at some point, LDPE is a good choice as it’s one of the less harmful plastics, and again, there isn’t much research on LDPE by itself, so we may be unaware of additional LDPE-specific risks.
Plastic #5: Polypropylene (PP)
PP plastic is used to make containers for yogurt, deli foods, medicine, and takeout, plus chip bags, diapers, carpet, packing tape, and menstrual products. PP is considered “microwave-safe” since it’s heat resistant and won’t change shape in the microwave, but that doesn’t mean it’s safe to eat foods that were microwaved in PP containers! PP leaches endocrine disruptors and other chemicals (with an especially high risk of asthma). One study found that PP food containers leach especially with heat and acidity. Polypropylene exposure can cause cell death, lung issues, cell harm, and inflammation in the intestine.
Plastic #6: Polystyrene (PS)
Polystyrene, A.K.A. Styrofoam, is used to make cups, plates, bowls, takeout containers, food packaging, and more. PS has been shown to leach many toxic chemicals, including styrene, which can damage the nervous system and is linked to cancer and gene, lung, liver, and immune damage. Higher temperatures increase the leaching of styrene from PS, which means using it for hot foods and beverages (like hot coffee in a Styrofoam cup) is worst of all. PS is linked to headaches, tiredness, dizziness, drowsiness, and attention disorders. It’s full of endocrine disruptors, especially estrogenic chemicals, and it can lead to thyroid issues, irregular menstruation, breast and prostate cancer, and liver and nerve damage. PS is especially dangerous to fetuses and small children. It’s even made by processing chemicals like benzene! This is one of the most toxic plastics, so really try not to use it.
Plastic #7: Other
Plastic #7 can be used to make baby bottles, sippy cups, big water jugs, medical containers, eyeglasses, and metal food can linings. This is a catch-all category for things made from other plastics not mentioned above or a combination of plastics. It almost certainly contains BPA and/or the newer, equally dangerous chemical BPS. Some of the greatest danger is in utero exposure to bisphenol chemicals, which can lead to chromosomal errors in a developing fetus, causing, in the best-case scenario, genetic damage, and worst-case, miscarriage, stillbirth, or significant health issues in the baby. In adults and children, exposure can lead to decreased sperm quality, early puberty, disrupted reproductive cycles, chronic diseases, ovarian dysfunction, cancer, and heart disease, among numerous other health problems. Plastic #7 specifically has been found to interfere with mood, growth, development, sexual, tissue, brain and neurological, and reproductive functions, and puberty, along with many other essential human developmental processes, and increase risk of reproductive cancers, obesity, heart disease, and type 2 diabetes. The scary thing about #7 is that it can be a combination of any and all plastics, so it can contain any and all of the chemicals mentioned above, and therefore any and all of their health concerns. Because of this, Plastic #7 is one of the most dangerous plastics and should be avoided.
Bonus: Bioplastics and Silicone
Bioplastics are made completely or partially from renewable biomass (organic matter) sources like sugarcane, corn, starch, or microalgae. Bioplastics made fully from renewable resources reduce fossil fuel use, can be decomposed or composted under very specific conditions, and have a smaller carbon footprint, which makes them better for the environment. However, when bioplastics are oxygen-deprived like in a landfill, they release a lot of methane, which warms the planet. One study researched 27 bioplastics, including all 3 categories of bioplastics - bio-based (made using biomass) and biodegradable (like PLA and PHA), petroleum-based and biodegradable (like PBS and PBAT), and bio-based and non-biodegradable (like Bio-PE and Bio-PET). They determined that bioplastics leach several toxic chemicals, including one commonly found in PE, that are especially harmful to nerve cells, can cause alterations in the gene expression of antioxidant enzymes, stress-response genes, and cytokines (which disrupts cell signaling) as well as genetic damage in general, and are endocrine disruptors. The study showed that bioplastics are just as toxic as traditional plastics, with a slightly higher percent of bioplastics being toxic to cells and a slightly higher percent of traditional plastics having endocrine disruptors. Silicone is synthetic and contains a bunch of chemical additives. Unlike traditional plastics, it’s made from silica (the element silicon in its common form) plus hydrocarbons from fossil fuels. Silicone is used to make pacifiers, utensils, muffin tins, toys, containers, beauty products, and more. Silicone cooking products can melt in too-high temperatures, which can cause liquid silicone to go in your food. Liquid silicone can move throughout your body and block blood vessels in the brain, heart, lymph nodes, lungs, or other organs, which can even lead to death. Many shampoos include liquid silicone, so always make sure to avoid those. Here’s a safe one, if you’re looking for a shampoo replacement! Silicone is also linked to immune damage, anemia, blood clots, memory difficulties, chest aches, eye issues, tiredness, fever, joint pain, hair loss, kidney problems, rashes, light sensitivity, and mouth sores. In product ingredient lists, silicones have names that end in -cone or -siloxane, like dimethicone, cyclomethicone, and cyclopentasiloxane, so those should be avoided. Silicone leaches siloxanes, especially at high temperatures and in the presence of high-fat foods. Siloxanes are endocrine disruptors, and exposure to them can lead to thyroid and autoimmune disease, uterine tumors and other reproductive issues, possibly even leading to permanent infertility, and cancer. If you have to use silicone, and it’s probably a better choice than traditional plastic when necessary, make sure it’s medical grade (preferably) or food grade (the higher the quality, the less leaching happens, so try to avoid below food grade). Toxic dyes that make silicone colorful also leach out, so always choose plain. You can test to see if something is pure silicone (without any other, usually cheaper and more dangerous, materials on the inside) by pinching, twisting, or stretching a flat part of it to see if any white shows through - pure silicone doesn’t change color. If you see white, it has fillers, and it’ll probably leach unknown chemicals. Never put silicone in the dishwasher or heat it, and if a silicone product becomes cloudy or worn out, replace it.
When possible, buy products that are not made of or packaged in plastic. There are plenty of plastic-free replacements out there now - try stainless steel, cloth, glass, wood, bamboo, natural rubber, or ceramic alternatives. I’m also happy to help if you’re looking for something in particular. I might start writing some quick articles on plastic-free substitutes, so let me know if you’d like that. It’s also a great idea to contact companies to try to persuade them to use a different material. Check the bottom of containers for the Resin Identification Code so you know any special dangers associated with them. Listed below are some additional tips:
Use glass, ceramic, stainless steel, wood, or bamboo containers
Use reusable shopping and produce bags for groceries
Use your own plastic-free water bottle or mug for hot beverages like coffee, tea, and hot chocolate
Bring drinking water from home in glass or stainless steel water bottles, instead of using bottled water
Store foods in glass, wood, bamboo, ceramic, or stainless steel containers instead of plastic ones or ziploc bags
At restaurants, request glass cups and non-plastic dishes for your food, and bring your own containers for leftovers
Request no plastic wrap on your newspapers and dry cleaning
Buy a microplastic filter for your laundry
Avoid plastic utensils, and use silver or stainless steel silverware, and wood or bamboo disposable utensils instead
Try to buy organic clothes and products made with organic fabrics when possible
Replace plastic kitchen- and tableware with glass, wood, stainless steel, bamboo, or ceramic replacements
Buy foods in bulk or at farmers' markets (as they often have cardboard packaging or none at all!) when you can, or find products that use plastic-free packaging
Eat fresh (hopefully organic!) food instead of canned, since canned foods often have plastic linings
Use beeswax wrap, wax paper, parchment paper, or lids instead of plastic wrap
Vacuum with a HEPA filter, get a good air filter capable of filtering out microplastics and dust, and wet mop household surfaces, as microplastics are found in dust and air
Wash your hands before eating
When possible, reduce your consumption of processed foods, as the less processed a food is, the less plastic it interacted with
Avoid stain- and water-resistant coatings, as these are often plastic
Cut back on seafood to avoid microplastics, and when eating it, try frozen fish as it avoids the endocrine disruptor-coated packages and additional plastic containers and packages – plus, choosing omega-3 fat-rich fish is healthier and better for freezing
Never, never, never microwave food in any type of plastic, including the bags or containers it comes in; when microwaving food, heat it in microwave-safe ceramic or glass and cover it with a paper towel instead of plastic wrap, or better yet, a glass microwave cover
Get a water filter to remove microplastics and other toxins from water
Taking small steps to remove plastic, especially PVC, PS, and Plastic #7, is important to minimize toxin exposure.
Thanks for this comprehensive information. It can feel overwhelming the amount of plastic used in almost everything in our daily life. I try to remember that small steps lead to big improvements. For example, I have replaced plastic food containers with glass, use parchment paper but not plastic wrap, replaced reusable plastic water bottles with steel, etc. I hope to see more food product companies return to glass packaging too. I look forward to more of your swap tips for items mentioned in this article that are typically plastic!