Styrofoam and Polystyrene Containers are Poisoning Your Food, Part 2

Last updated on September 11, 2021.

Yellow warning sign with skull and crossbones
Image by OpenIcons from Pixabay

In Part 1 of this series, I introduced polystyrene, which we commonly refer to as Styrofoam, food packaging. This type of plastic is terrible for the environment and human health. Today, we’ll look at the toxicity of polystyrene in depth.

After watching friends and coworkers repeatedly reheat their take-out and leftovers in polystyrene, I decided to write a post about it. I had known polystyrene was potentially toxic for a long time, but I had no idea of the breadth of the problem.

Chemicals Leach from Containers into Food

Polystyrene leaches styrene and benzene, chemicals that have known toxic properties, into food. In testing, one scientific journal independently tested and found that polystyrene leaches more toxins when in contact with high-temperature contents and into foods with higher fat content.1 What does this mean? It means that if you buy hot food, fatty food, soup, or coffee and it is packaged in polystyrene, some of the chemicals from the container leach into your food. Over time, these chemicals can cause severe health problems.

“Styrene is likely to leach when it comes in contact with fatty foods, hot beverages, and especially alcohol. When thinking about the kinds of foods that typically end up in Styrofoam containers (fatty foods) and cups (hot coffee), it seems as though the exact kinds of items Styrofoam contains are exactly the kind of items it should never touch.” -The Green Dining Alliance2

Melted polystyrene spots from hot food in a polystyrene container.
I recently went to a BBQ restaurant in Dayton, TN. They serve most of their food in polystyrene containers. My fried okra side melted the polystyrene and those chemicals certainly leached into my food. I didn’t eat the okra, I dumped it out so that I could photograph the container. I likely will never dine at that place again. It really concerns me that people eat food out of these types of containers every day! Photo by me
Melted polystyrene spots from hot food in a polystyrene container.
Photo by me

Known Toxicity

When I searched “polystyrene human health” I got more than 13 million results. After reading many articles, I realized that all organizations and even the government, including the Environmental Protection Agency (EPA), know that polystyrene is harmful to human health as well as land and marine environments. Furthermore, the Food and Drug Administration (FDA) permits the migration of styrene from packaging into food!

Study after study shows that chemicals from polystyrene leach into foods and beverages, especially with higher temperatures and food with higher fat content. And study after study shows that styrene is dangerous to human health. In fact, most agencies caution against the use of polystyrene because of the known health hazards, including:

        • The Environmental Protection Agency (EPA)
        • The World Health Organization (WHO)
        • The International Agency for Research on Cancer
        • National Institute for Environmental Health Sciences
        • U.S. Department of Health and Human Services (DHHS)
        • National Research Council (NRC)
        • Occupational Safety and Health Administration (OSHA)
        • National Institute for Occupational Safety and Health
        • The Agency for Toxic Substances & Disease Registry (ATSDR), Center for Disease Control and Prevention (CDC)
Take-out in polystyrene containers
Image by albedo20 on Flickr, Creative Commons license (CC BY-NC-ND 2.0)

A Known Carcinogen

Styrene exposure increases the risk of leukemia and lymphoma and is a neurotoxin. This alone is enough reason to avoid polystyrene containers. In 2018, the World Health Organization (WHO) reclassified styrene as a probable carcinogen.3 While the EPA does not classify it as a carcinogen, it noted that animal cancer studies provided some evidence for carcinogenicity.4 Several of the organizations mentioned above, including the International Agency for Research on Cancer and the Department of Health and Human Services consider it to be carcinogenic.

Hormone Disruption

There are countless studies that show certain types of plastics contain known hormone disruptors. Those chemicals often mimic estrogen and they seep into food and beverages (including breastmilk). In 2014, Environmental Health tested 11 samples of polystyrene and consistently found estrogen seepage after exposure to intense steam or ultraviolet rays5. Since polystyrene is a type of plastic, this is just one more reason to avoid polystyrene containers.

It is terrifying that many schools use foam trays for cafeteria food. Hormone disruption in young children prevents them from developing normally, can affect their ability to reproduce as adults, and can set them up to be prone to other diseases.

Polystyrene food tray
Image by Laura Taylor on Flickr, Creative Commons license (CC BY-NC-ND 2.0)

Other Health Hazards

Styrene exposure can come from other sources, such as photocopier toner, automobile exhaust, and plastics manufacturing. Exposure can cause irritation of the skin, eyes, mucous membranes, the upper respiratory tract, and gastrointestinal irritation. Chronic exposure can cause neurological problems such as depression, headaches, fatigue, weakness, hearing loss, and disrupted kidney function.6

Additional Unknown Chemicals

There are many chemicals and ingredients that are not tested for and not regulated by the EPA and FDA. While this may seem surprising, the standard operating procedure in the United States is to allow the chemical to be used until a known hazard is not only discovered, but proven. Essentially, chemicals are innocent until proven guilty.

Hefty polystyrene container
Hefty polystyrene container, photo by me

Exposure through Manufacturing

Anyone who lives near or works in polystyrene manufacturing sites are at risk of even greater health problems due to respiratory exposure. The Clean Water Action organization noted that “occupational exposure to Styrene increases [the] risk of lymphoma, leukemia, lung tumors, pancreatic cancer, urinary bladder cancer, prostate cancer, and colorectal cancer. High rates of neurotoxicological effects have been reported in workers,” as well as decreased sperm counts.”7 These plants also emit a toxic and volatile gas called pentane, often used as a blowing agent in the production of polystyrene. 

“Over fifty chemical byproducts are released during the manufacturing of polystyrene, contaminating the air, water and communities that live near these facilities.” Children’s Environmental Health Network

What You Can Do

Polystyrene is toxic to human health. When ordering take-out, ask the restaurant if they use “Styrofoam” or polystyrene containers, and if they do, you can either ask if they have an alternative type of container or decide to order from somewhere else. When bringing leftovers home from a restaurant, keep a glass or metal container in your car specifically for such occasions. Bring your own reusable coffee mug to coffee shops. As I mentioned at the beginning of my post, please try to avoid eating food in polystyrene, and definitely stop reheating your food in polystyrene containers in the microwave

Last, polystyrene is the most common type of #6 plastic and is largely not recyclable because of food contamination. In Part 3, I will cover the problems with recycling and the environmental damage polystyrene causes. Thank you for reading, and please subscribe!

 

Additional Resources:

“Styrene,” Report on Carcinogens, 14th Edition, National Toxicology Program, Department of Health and Human Services.

Report, “What’s the Package? Unveiling the Toxic Secrets of Food and Beverage Packaging,” Clean Water Action and Clean Water Fund, August 2016.

Article, “Leaching of styrene and other aromatic compounds in drinking water from PS bottles,” by Maqbool Ahmad and Ahmad S. Bajahlan, Journal of Environmental Sciences, 19 (2007), p. 421–426, accessed September 12, 2021.

Footnotes:

Styrofoam and Polystyrene Containers are Poisoning Your Food, Part 1

Last updated June 20, 2021.

Black Styrofoam take out container
Photo from www.webstaurantstore.com

Take-out has definitely increased in popularity since the onset of COVID-19 and often take-out and leftovers are transported and served in what we colloquially refer to as Styrofoam containers. These containers present several problems because they largely cannot be recycled or composted. These items clutter up landfills, litter rivers, and pollute oceans. They are extremely dangerous to marine life because the containers break down into small pieces that many species ingest. Worst of all, these containers leach toxins into our food, and those toxins are poisonous to humans.

This is the first of a five-part series to explain the dangers of putting food into said containers. I want to acknowledge that I am neither a physician nor a scientist. I am, however, a concerned environmentalist, mother, and friend, and as such I must inform you that I feel it is imperative to stop eating and reheating food in Styrofoam/polystyrene containers immediately.

Styrofoam vs. Polystyrene

Foam take-out containers are actually made of polystyrene, which is how I’ll refer to them in this post. Though it has become a genericization, Styrofoam is a trademarked brand of closed-cell extruded polystyrene foam (XPS), commonly called “Blue Board” and used in building materials and insulation. This material is light blue in color and is owned and manufactured by The Dow Chemical Company. The kind used for take-out and food packaging is actually Expanded Polystyrene, or EPS. Both types have insulating and cushioning properties.

“Polystyrene is the name for a whole family of plastics … but the foam forms have [a] disproportional environmental impact.” -Joseph A. Davis, Society of Environmental Journalists

Styrofoam food container
Styrofoam food container. Image by Aislan Máximo “Max” on Pixabay

What is Polystyrene?

Polystyrene is a chemically produced plastic that can be a hard or foam plastic. The foam is created by expanding the styrene (plastic), a petroleum by-product, which is accomplished by blowing various gases into it. Polystyrene is made from ethylene and benzene, both hydrocarbons derived from petroleum and natural gas, also known as petrochemicals. So those fast-food containers are made from fossils fuels and mixed with chemicals. That doesn’t sound too appetizing, does it?

The American Chemistry Council (ACC), promoters of all plastic despite the human health and environmental problems it causes, infers that polystyrene is natural when it is far from it: “Polystyrene is made by stringing together, or polymerizing, styrene, a building-block chemical used in the manufacture of many products. Styrene also occurs naturally in foods such as strawberries, cinnamon, coffee and beef.”1 They are referring to the minuscule amounts in those natural items, which are not mixed with additional additives and chemicals that are potentially dangerous. I find it appalling that the ACC makes such a comparison.

Added Chemicals

Many sources indicate that polystyrene is made up of mostly air, but that’s not completely accurate. The plastic is expanded into foam by creating air pockets between the polymers, but a gas or a chemical is used in expanding it. The industry formerly used chlorofluorocarbons (CFCs) as a blowing agent, and as you may know, CFCs deplete the planet’s protective ozone layer. Most CFCs have been removed worldwide following bans in the late 1980s.2

Today, there are two principal methods of production for polystyrene in the United States, according to the CDC’s Agency for Toxic Substances and Disease Registry. The primary method uses ethylbenzene; the second is created through a series of chemical reactions using ethylbenzene, propylene, propylene oxide, and α-methyl phenyl carbinol.3

Chicken, rice, and vegetables in polystyrene container
Image by Vitalis Arnoldus from Pixabay

Use of Polystyrene Containers

Polystyrene is used for packaging materials, insulation, fiberglass, automobile parts, plastic pipes, carpet backing, boat hulls, and food packaging and containers. There are two types of EPS food containers. The rigid form is used for clear food containers, plates, bowls, beverage cups and lids, utensils, and straws. The foam form is used to make plates, insulated beverage cups, soup bowls, ice cream cups, clamshell food containers, meat trays, and cafeteria trays. These containers are everywhere: restaurants, fast-food restaurants, cafeterias, buffets, coffee shops, ice cream shops, movie theaters, grocery stores, supermarkets, etc.

Keebler ice cream cones, packed in #6 polystyrene packaging.
Keebler ice cream cones, packed in #6 polystyrene packaging. Photos by me

Keebler ice cream cones, packed in #6 polystyrene packaging.

Inexpensive but Harmful

This material is inexpensive to manufacture. It is also cheap to ship because polystyrene is so light, but it also makes it easy for the pieces to take to flight, littering our roads, rivers, and ocean. The ACC really promotes the use of material despite environmental and human health hazards: “Polystyrene foodservice packaging typically insulates better, keeps food fresher longer and costs less than alternatives.”4 But the true cost is devastating when considering the pollution, human health effects, and harm to wildlife.

“When considering the cleanup costs, carbon emissions, environmental costs, and potential health effects, the hidden cost of Styrofoam comes out to $7 billion, annually.” -Green Dining Alliance of St. Louis

Looking Forward

The world produces more than 14 million US tons of polystyrene each year according to earthday.org and the Green Dining Alliance. Most of that ends up in the trash or worse, our land, rivers, and ocean. Polystyrene is the most common type of #6 plastic and is largely not recyclable because of food contamination. I will explore these topics more in Part 3 of this series. For now, please know this, these containers leach harmful chemicals into your food, especially when heated. The best thing you can do is not to use them.

When ordering take-out, you can always ask the restaurant if they use “Styrofoam” or polystyrene containers. If they do, you can either ask if they have an alternative or decide to order from somewhere else. When bringing leftovers home from a restaurant, keep a glass or metal container in your car specifically for such occasions. It’s also a good idea to bring your own reusable coffee mug to coffee shops. As I mentioned at the beginning of my post, please try to avoid eating food in polystyrene, and definitely stop reheating your food in polystyrene containers in the microwavePolystyrene is toxic to human health. I will cover this in more detail in my next post, Part 2.

Thank you for reading, and please subscribe to keep up with this short series and others to come!

 

Additional Resource:

Article, “Is the 30-Year-Long Styrofoam War Nearing Its End?” by Katherine Martinelli, JSTOR Daily, 

Footnotes: