Recently, the issue of single-use plastic and its impact on the environment has come to the fore, with many companies vowing to cut back their plastic use, and increased media coverage across the globe. It isn’t difficult to see why there is a growing passion for addressing the problem of plastic—its environmental significance is truly shocking—and in 2016 the Ellen MacArthur Foundation published a report that concluded there will be as much plastic in the ocean as fish by 2020.
But what about the impact of plastic on human health?
A survey of research findings of human health problems, that correlate with exposure to chemicals associated with plastics, reads like a catalogue of modern Western diseases. Plastic has saturated our environment, leaving our health vulnerable to the dozens, if not hundreds, of industrial chemicals we are exposed to every day. In the not too distance future, it is likely that medical professionals will need methods for assessing the plastic load in their patients.
Read on for more information about the chemicals that make up common plastics and the part they play in various health problems.
Bisphenol A (BPA) previously garnered positive, rather than negative, medical attention as it was considered for use as synthetic oestrogen. However, the discovery that BPA could be used in the creation of shatter-proof polycarbonate plastic led to its widespread use in everyday household items, and prompted an avalanche of research into this curious substance.
The Endocrine society has identified BPA as an “endocrine disruptor” and, in 2012, detailed how it could derail normal cellular function and organ development, particularly during the foetal and neonatal stages of human growth. Studies in mice have indicated that BPA’s effects can be multigenerational, and long-term exposure to the chemical has been linked to female infertility, lowered sperm quality, polycystic ovarian syndrome, cardiovascular disease, and obesity.
Despite the extensive list of detrimental consequences of BPA exposure on human health, industry pushback has often stalled national regulations that would reduce the production or use of BPA. Worldwide, BPA production is almost 5 million tonnes.
Studies dating as far back as the 1930s demonstrated that even short-term exposure to vinyl chloride in lab animals and factory workers caused liver damage. In 1980, the National Toxicology Program listed vinyl chloride as a known human carcinogen, which doesn’t just affect the liver, but also includes the brain, lungs, and lymphatic and hematopoietic systems.
Today, there is a lower risk of ingesting vinyl chloride, after government bodies reined back the use of PVC in food packaging and films. However, swallowing or inhaling dust emitted from consumer products made with PVC remains a possible vulnerability.
The International Agency for Research on Cancer (IARC) has determined that styrene is a possible carcinogen, and studies in mice exposed to styrene by inhalation or ingestion indicate that it causes cancer of the lung.
For the general public, breathing indoor air and ingestion of styrene migrants in food and beverages packaged or served in polystyrene are the primary routes of exposure. Although evidence of styrene carcinogenicity is humans is more limited, the central nervous system is deemed to be the most sensitive target of styrene toxicity in humans. Chronic occupational exposure can cause tiredness, feeling drunk, slowed creation time, and impaired concentration, balance, and colour vision.
Phthalates are ubiquitous in manufactured products, and therefore widespread in the general population. Women and children typically show greater exposure than men, and in a nationally representative sample of the US population (National Health and Nutrition Examination Survey [NHANES] 2003-2004), all of the pregnant women tested positive for at least four phthalates.
Like BPA, phthalates are endocrine disruptors. More specifically, they are antiandrogenic endocrine disruptors, and exposure to phthalates is linked with impaired genital development, reduced semen quality and sperm DNA damage, pubertal gynecomastia, and premature thelarche.
Featured image credit: 426187984 by Mohamed Abdulraheem via Shutterstock.