What is Polyethylene?

Karyn Maier
Karyn Maier

Polyethylene is a type of polymer that is thermoplastic, meaning that it can be melted to a liquid and remolded as it returns to a solid state. It is chemically synthesized from ethylene, a compound that's usually made from petroleum or natural gas. Other non-official names for this compound include polythene or polyethylyne; and it is also abbreviated as PE. It is used in making other plastic compounds much often than it's used in its pure form. Though it has a wide variety of uses, it can be harmful to humans and to the environment.

Polyethylene is used in many common items, including the plastic grocery bag.
Polyethylene is used in many common items, including the plastic grocery bag.

Production and Uses

Of all the plastics produced for industrial and commercial products, polyethylene is the most common. As an example, 280 million metric tonnes of it was produced in 2011 alone. Over five times as much PE is manufactured each year than a closely-related compound, polypropylene (PP). The largest use for these polymers is in packaging materials, like films and foam; and for bottles and other containers that can be used in food, medical, and other consumer industries.

Ultra high molecular weight PE, a type of polyethylene, is used in bullet proof vests.
Ultra high molecular weight PE, a type of polyethylene, is used in bullet proof vests.

The characteristics of a plastic can be adjusted by combining it with various plasticizers, which are substances added to plastics to make them more durable, flexible, and transparent. Adding chromium/silica makes high-density polyethylene (HDPE), which is used to create sturdy products like garbage containers. Combining it with organic olefin compounds makes a type of low-density PE (LDPE) that is used for plastic grocery or shopping bags. Other common forms of polyethylene are ultra high molecular weight PE (UHMWPE), which is used in bullet-proof vests and knee joint replacements; and medium-density PE (MDPE), which is crack resistant for applications in gas pipe pressure fittings.

Polyethylene foam can be used for insulation.
Polyethylene foam can be used for insulation.

Plastics based on the PE molecule are widespread because the compound has physical characteristics that are considered safe and useful in a range of environments. These traits include the fact that it remains pliable for an extended period of time while remaining inert and impervious to damage by most liquids. Since its softness and strength level can be easily adjusted and it can be dyed many colors, it is often used in consumer products from food wrap to shampoo bottles, milk containers, toys, and grocery bags.

Some studies indicate that phthalate may contribute to the development of obesity.
Some studies indicate that phthalate may contribute to the development of obesity.

Potential Dangers

Depending on the compounds its bonded with, PE's level of toxicity and flammability varies considerably. There are concerns about two versions of the compound in particular, both of which are often used for medical and consumer purposes. Polyethylene-glycol (PEG), which acts as a binding agent for many drugs and is also found in products like shampoo and toothpaste, can cause allergic reactions in certain individuals. Some people experience nausea, flatulence, and diarrhea after being exposed to it, while others get a hives-like rash. The elderly seem to be particularly prone to these side effects.

In addition, harmful chemicals — including the plasticizer phthalate — may leach from polyethylene-terephthalate (PET), which has been widely used in the plastic bottling industry. Phthalate is associated with hormonal imbalances, increases in allergies, and reduced fertility. Some studies show that it may also contribute to the development of obesity and breast cancer.

Environmental Impact

While PE may help to make many useful and durable products possible, its environmental impact concerns many experts. It doesn't biodegrade easily, and can sit in a landfill for hundreds of years. About 20%-24% of all landfill space in the US alone is taken up by plastics, including polyethylene products. However, recycling may reduce this problem, since PE scrap can be melted down and reused.

Additionally, an aerobic bacteria called Sphingomonas can significantly reduce the amount of time it takes some forms of PE to break down, though it is not yet widely used. Environmental preservation efforts have also led to the development of bioplastics, with the aim of creating polyethylene from ethanol made from sugarcane.

Polyethylene is widely used to make plastic bottles for milk, soda and other beverages.
Polyethylene is widely used to make plastic bottles for milk, soda and other beverages.
Karyn Maier
Karyn Maier

Contributing articles to wiseGEEK is just one of Karyn’s many professional endeavors. She is also a magazine writer and columnist, mainly for health-related publications, as well as the author of four books. Karyn lives in New York’s Catskill Mountain region and specializes in topics about green living and botanical medicine.

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Discussion Comments


I'm not sure if PET is a version of polyethylene. I know that it ethylene is stated in the name however there is a difference. Polyethylene PE has the formula (C2H4)nH2 and is made up of monomers of ethylene. PET on the other hand is made up of ethylene glycol and terephthalic acid and has a very different formula.

It is tempting to think they are similar because of the ethylene part of the words, and because they are both plastics but it is important to realize that they actually have very different sources and do not share the same ethylene monomer content, therefore I'm not sure its right to say PET is a version of polyethylene.


For those of you becoming sick, and losing hair from use of this product, do not depend on any information from the manufacturer or any health trials financed either directly or indirectly from the manufacturer or those related to, either directly or loosely, as they have financial gain directly associated with the sale, legality and positive outcomes of such studies.

Research the safety data sheets, which by law, must be made available for any chemical sold or otherwise likely to be in contact with humans. California is one of the more consumer friendly states as a good place to start. These large corporations have a lengthy history of acting in fraudulent, dishonest and unethical ways. Also, the many wonderful US laws and others protect the corporate interests over your own health, since most, if not all "proprietary" ingredients and/or chemicals do not have to be listed nor tested for toxicity.

Furthermore, these companies and industries are heavily lobbied by special interests and are paid to turn the other cheek. A prime example would be the aviation turbine oil used in commercial jet aircraft. It contains very toxic compounds such as organophosphates, which are used in chemical warfare and pesticides. Often, this oil leaks and is heated, and then the fumes enter the aircraft passenger cabin. These chemicals are neurotoxic and cause long term illness and disability in passengers and even higher incidences in flight crews as they are exposed daily over entire careers etc. Look up Aerotoxic Syndrome or toxic cabin air, and you'll have plenty to read. It's an eye opener and a huge coverup by the airlines, those that regulate them and the oil companies.

Don't trust the government and those you think are there to protect your health. They don't care and we are just acceptable losses in their billion dollar industries. Humans lie and when money is involved, they lie even more. I had to learn the hard way myself.


What are the additives or plasticizers of polyethylene?


I just received two rolls of cushion-pak foam that I had intended to use in preparing household goods for moving to anther location. A warning on the roll suggests that these rolls of foam be stored in a well ventilated place and away from any source of ignition.

I began wondering how safe this polyethylene product really is, whether it is readily flammable, and how it would "travel" in a closed moving truck for three days. I am sure this foam product is widely used, but I am concerned about potential damage to household goods and art objects over the long haul. Do you have any suggestions?


Which material, PE or PP, is more suitable for manufacturing medical gowns, wipes and tray wraps and why? I have seen a lot of PE being used but what are the reasons behind it. I have seen the softness of the surface (of the finished product)being mentioned quite often as the desired output but would PP not give the same results? Is PE stronger than PP when made into light spun bond, thermally bonded fabrics?

Responses will be much appreciated!


I was taking Miralax on a regular basis to offset the side effects of a calcium channel blocker. I experienced significant hair loss. I saw my doctor and was tested for possible disease related causes and the tests all came back fine. I then assumed it was one of the heart medicines. I am now off all of the heart medicines (with medical approval) and off the Miralax.

My hair has grown back, except I have noticed with the occasional use of Miralax, the hair loss returns. Miralax is over the counter. Thus, I thought it was safe. I was wrong.


do polyethylene bags outgas?


Post 8: The polyethylene beads will not block the septic tank lines, as they will eventually break down, particularly if there is a UV source. However, if it's a concern you can switch to body scrubs using salt/ sugar granules, and face scrubs using nut husk particles as the exfoliate source.


I have just mistakenly drank the ice in the polar pack. From my understanding, it contains Polyethylene. is it harmful to humans?


I have been taking Polyethylene Gycol (Miralax) for almost a year and have had thinning hair ever since. I have slowly stopped all drugs and other possible causes. Therefore I must conclude that Miralax Is the cause. I am slowly weaning off of Miralax and hope I'm right.


What about polyethylene fill for pillows? How toxic is that for us to be sleeping on every night?


Polyethylene is used in toothpastes. Colgate brand, 125ml tube, sku # 8 714789 058382. Poison!


I found out that polyethylene mixed with mica and graphite makes a good material to make bonsai pots. Can anyone tell me in what form that polyethylene will be and if any water is needed to make the paste.


I am concerned about the safe use of a body scrub product that uses polyethylene as the gritty exfoliating substance. The company says that it is biodegradable, but I rubbed it strongly between my figures and it did not break down.

I am concerned about its use in my septic tank. I have two teenage daughter who use this product every day. Anything that doesn't biodegrade in the septic tank will eventually block the flow of water to the leach lines.


I am taking Polyethylene glycol (Miralax) also. If Polyethylene glycol isn't plastic what is it? Everything I have read says polyethylene is a plastic. Please clear this up for me. Thank you.


what is the best method in connecting/ jointing the edges of the polyethylene sheet so that the liquid inside does not leak when i want to construct a water storage?


No, you're not ingesting plastic. But, hair loss is not a known side effect of Miralax, so you should probably see your doctor.


Since I've been taking Polyethylene Glycol (Miralax) my hair is coming out. Am I ingesting plastic by taking Miralax? Could that be causing my hair to fall out?


Thank you for this clear and understandable summary!

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