The perils of plastic

He’s written about our addiction to fossil fuels and our frightening dependency on chemicals. Now, in order to get us thinking twice before reheating that yummy burger in its polystyrene container, VITTORIO BOLLO addresses the third element in this unholy trinity – plastics.

Plastic is everywhere. It invades our daily life like an amorphous entity, reproducing itself in a seemingly endless array of forms. Fossil fuels may power the world economy, but plastics are like chemicals – they’re pervasive to the extent that we cannot separate our lives from them.

Plastics are almost always synthetic, although some are partially natural. Plastics are defined as being typically organic polymers of a high molecular mass (read: extremely difficult to break down naturally). Before getting excited by the notion that plastics are “organic” and, therefore, somehow “natural”, it should be remembered that in order for something to be organic it need only be comprised of carbon. The “organic” here is due to the fact that most plastics are in some way petroleum-base, hence “organic.”

Polymers are large molecular, repeated structural units. Rubber, amber and the cellulose that assists in making paper are all naturally-occurring polymers. Synthetic polymers include synthetic rubber, Bakelite, neoprene, nylon, PVC, polystyrene, polyethylene, polypropylene, silicone and countless others. Many of these are varieties of plastics. The name for nylon, by the way, was a word made up by the scientists who invented it as an amalgamation of the words New York (ny) and London (lon); trivia rules!

There’s no denying that plastics are incredibly useful and versatile – they’re lightweight, flexible, moisture- and corrosion-resistant, durable, strong and relatively inexpensive to manufacture. It is the primary packaging of many of the products we buy, and it allows us to keep food longer and more hygienically. However, it’s the impact of most plastics on human health and the environment that is of such concern to many health specialists and environmentalists.

The health implications of plastic are considerable. It’s important to note that most plastics need chemical additives to give them their desired properties. For example, the commonly used polyvinyl chloride (PVC) can contain up to 55 percent plasticising additives. These are generally what is known as phthalate chemicals. The problem with phthalates is that they are known “endocrine disruptors”; they disrupt the endocrine (or hormone) system in the human body. The endocrine system consists of glands that secrete hormones, and receptors that detect and react to the hormones. Endocrinal disruptions can cause cancerous tumours, birth defects and other developmental disorders. These disruptors are also known to cause learning disabilities and can result in severe attention deficit disorder, cognitive and brain development problems, deformations of the body (including limbs) and sexual development problems, including infertility in both men and women.

Another endocrine disruptor used in certain plastics is bisphenol A (BPA). Peer-reviewed scientific studies have linked BPA to health problems that include chromosomal and reproductive system abnormalities, impaired brain and neurological functions, cancer, cardiovascular system damage, adult-onset diabetes, early puberty, obesity and even resistance to chemotherapy. Some of these plasticising chemicals have been banned by the European Union for use in certain products, such as toys.

Different plastics have different effects on human health that go beyond endocrine disruption. It’s also important to stress here that certain plastics have been studied with regard to their health effects more than others. In addition to creating health and safety risks during the actual production of plastic, many of the chemical additives that give plastic products their desirable properties have other negative human health effects. These can include direct toxicity due to the use of lead, cadmium, and mercury, or indirect toxicity due to known carcinogens, as is the case with diethylhexyl phthalate (DEHP).

Internationally, plastics are typically arranged into seven broad categories, the numbers of which can often be found on plastic goods; for example, at the bottom of plastic bottles. These numbers are worth knowing.

They comprise:

1. Polyethylene terephthalate (PET or PETE) – mostly used in the production of clear plastic containers. The problem with this plastic is antimony trioxide. Workers exposed to antimony trioxide for long periods have exhibited respiratory and skin irritation, while among female workers there have been increased incidence of menstrual problems and miscarriage. The longer a liquid is left in a PET container, the greater the potential for release of antimony into the liquid.

2. High density polyethylene (HDPE) – mostly used in opaque (non-clear) plastic containers, this is considered a “safer” plastic, which isn’t to say there are no health effects in the production or use thereof.

3. Polyvinyl chloride (V or Vinyl or PVC) – used in toys, clear food and non-food packaging (such as cling wrap), some squeeze bottles, shampoo bottles and so on. PVC has been described as one of the most hazardous consumer products ever created. It has been strongly linked to asthma and allergic symptoms in children, may cause certain types of cancer, and has been linked to adverse effects on the liver, kidney, spleen, bone formation and body weight.

4. Low density polyethylene (LDPE) – used primarily in plastic bag production, most plastic wraps and squeezable bottles (such as those used for honey and mustard). This is considered a “safer” plastic, but again, the precautionary principle should apply here.

5. Polypropylene (PP) – used in some plastic bottles, yoghurt and margarine tubs, medicine and syrup bottles, straws and so on. PP is considered a “safer” plastic.

6. Polystyrene (PS) – used in Styrofoam containers, egg cartons, disposable cups and bowls, take-out food containers, plastic cutlery and compact disc cases. This plastic leaches styrene, which is also an endocrine disruptor. Long-term exposure by workers has shown brain and nervous system effects. It has also been shown to have adverse effects on red blood cells, the liver, stomach and kidneys in animal studies. Worryingly, styrene migrates very easily from polystyrene containers into the container’s contents when oily foods are heated in such containers.

7. Other – this is a catch-all category that includes all plastics not in any of the other six categories. Extreme caution should be used with this category, given that it can include polycarbonate, which is a very hazardous plastic used to make plastic cups, compact discs, computers and cell phones. But this category also includes the new era of safer, biodegradable plastics made from renewable resources such as corn and potato starch, and sugar cane.

A rule of thumb is to try use plastics 2, 4, 5 and (with much caution) 7 wherever possible. Given that the disposal and recycling of plastics are environmental issues, and that the emphasis here is on the health implications of plastics, one must try to avoid plastic use wherever possible, particularly with regards to food, beverages and other products one buys. However, that’s easier said than done. Try avoiding plastic on your next trip to the shops – it’s probably not possible.

Yet the health implications of plastics and the chemicals they contain are either very well-known or haven’t yet been effectively ascertained. In sustainability, one strives to always offer solutions, and packaging alternatives using stainless steel, cotton or cellulose do exist.

To avoid plastic in this day and age is, however, a gargantuan task. Our addiction to plastic has devastating effects on the environment, which I will explore in a follow-up article. Much as our lives are awash in plastic, so too is the planet.

Vittorio Bollo achieved an LL B in Law and Politics from a UK university and a Master’s degree in International Environmental Law from a Canadian university. He has over 12 years experience in the SHE field, primarily in consulting, training and R&D. He joined NOSA to work in its growing R&D department, where he continues to do work in environmental/SHE risk management and corporate governance, as well as his chief passion, sustainability.