Dioxins/furans: Dioxins are a family of chemicals that are some of the most highly toxic substances known. Dioxins and furans are not produced intentionally (and because they are produced unintentionally, they are sometimes referred to as U-POPs). However, it is well known that they are created when other chemicals are made or disposed of by burning – for example, when plastics are incinerated or burned. Dioxins can cause reproductive and developmental problems, damage the immune system, interfere with hormones, and cause cancer. Chlorinated dioxins and furans were among the original “dirty dozen” persistent organic pollutants (POPs) listed for global elimination under the Stockholm Convention. Brominated and bromo-chlorinated dioxins and furans have been shown to have the same concerns and have recently been nominated for global restriction under the Stockholm convention.
PBDEs/BFRs: Polybrominated diphenyl ethers (PBDEs) are a type of brominated flame retardant (BFR), which are chemicals added to plastics, including electronics, to make them resistant to heat or flame. BFRs are endocrine disrupting chemicals that have been found to disrupt reproductive development, alter thyroid development, and affect neurodevelopment in children. While certain PBDEs are listed in the Stockholm Convention for elimination, there remain many types of BFRs on the market which are similarly toxic. For example, a 2020 study on newer (“novel” or NBFRs) found that “…more and more evidence reveals the neurotoxic effects of NBFRs.”
Polychlorinated biphenyls (PCBs): A highly carcinogenic and neurotoxic group of chemicals banned under the Stockholm Convention as one of the original “dirty dozen” persistent organic pollutants (POPs). It was widely used in industrial and consumer applications, including plastics, insulation, coatings, paint, and many others. Despite its ban, PCBs continue to be a health threat due to their resistance to breakdown in the environment, continued use, and longevity of products and materials that were manufactured with PCBs before its ban, and as a known byproduct of certain production processes.
Bisphenol A (BPA): The chemical building block used to produce polycarbonate plastics and epoxy resins, and a common additive in plastics. BPA is found in many consumer goods, such as food containers, food can linings, eyeglass lenses, plastic water pipes, and thermal receipt paper. Human exposure is extremely widespread. BPA is an endocrine disruptor and associated with breast, prostate, ovarian, and endometrial cancers. While many countries have moved to ban BPA, other replacement chemicals within the bisphenol group may exhibit the same health impacts.
Phthalates: Known as “everywhere chemicals” due to their extremely widespread use, they are used in plastics to increase flexibility and are found in fragrances and personal care products. Like many plastic chemicals, they do not permanently bind to plastics and can transfer easily to anything that comes in contact with plastic during production, transport, and use. These substances are endocrine disrupting chemicals that may lower testosterone and estrogen levels, impair thyroid function, and are reproductive toxicants.
UV stabilizers: Used to prevent plastic degradation from sunlight, these chemical additives can leach from plastic products and packaging into food and the environment. Studies have shown that some can act as endocrine disrupting chemicals and can impede fertility and development.
Chlorinated Paraffins: These are high production volume mixtures characterized by the size of molecules (i.e., carbon chain length) which comprise the substance, so are typically referenced as short-chain, medium-chain, or long-chain chlorinated paraffins. Regardless of chain length all these groups of chemicals have shown to have similar concerns. They are used as flame retardants or to make plastics more flexible. These complex mixtures are endocrine disruptors and suspected carcinogens. Studies have shown that they affect the liver, kidney, and thyroid.
Per- and polyfluoroalkyl substances (PFAS): Known as “forever chemicals,” this group of more than 10,000 chemicals that are extremely resistant to environmental breakdown and accumulate in wildlife and people. They are often used to make products stain-, water-, and grease-resistant, and are a chemical building block in producing some plastics and coatings like polytetrafluoroethylene (PTFE). PFAS are endocrine disruptors that affect the immune system, liver, and thyroid, and have been linked to cancer and reproductive harm.
Endocrine disrupting chemicals (EDCs): Any substance or mixture that interferes with natural hormone function. Hormones are produced by our endocrine glands and are vital to human development and maintenance of our health. EDCs impair the endocrine system and can lead to a variety of disorders and diseases. Studies have shown that many plastic chemicals are EDCs. Most chemical regulation policies have not caught up to the latest science on EDCs as these chemicals can be harmful even at low dosages, meaning that there may be no safe level of exposure.
Heavy Metals: Several groups of toxic metals are used in plastics to provide material characteristics like color or durability. These include dangerous lead compounds like lead chromium, which are neurotoxins and particularly harmful to children. Other toxic metals such as arsenic and chromium have been found in studies of plastic toys and other products. Some older types of PVC-plastic production release mercury that can contaminate the environment and nearby food chains.
Microplastics: Plastic particles that are less than 5mm in length (even smaller particles may be referred to as nanoplastics). They have been detected in virtually every environment studied—land, water, air—and throughout the human body—in blood, saliva, and breast milk, among others. Microplastics may act as a transport mechanism for toxic chemicals found in or on the particles, and researchers are still learning how microplastics impact human health. As these particles accumulate within our bodies, researchers are concerned about cancer risks and impairment of our bodily processes, including digestive, respiratory, endocrine, reproductive, and immune systems.
Polycyclic Aromatic Hydrocarbons (PAHs): A large class of chemicals found in fossil fuels and produced during burning of fuels, wastes (including plastics), and as a byproduct of other industrial processes. Some PAHs are persistent and accumulate in soil and several are carcinogenic and may be harmful to the reproductive and immune systems.
Alkylphenols: A group of chemicals with wide industrial use, they are used as additives and intermediates in plastics to add durability or flexibility. They are also commonly used in formulating detergents, cleaning agents, personal care products, pesticides, and paints. These chemicals impact hormone function by mimicking estrogen and disrupting the reproductive system and may also be associated with a heightened risk of breast and endometrial cancer. Additionally, they are considered to be highly toxic to aquatic animals.