PLASTICS ARE A HAZARD TO HUMANS AND ANIMALS
With biodiversity and our health at stake, we cannot wait to act, Dr. Sharon Dodd says.
As a practising family physician and member of the Canadian Association of Physicians for the Environment, I am especially concerned about the serious health hazards of plastics on human health, in addition to the harms of plastic on all the ecosystems in the world.
That's why I'm watching closely as Canada hosts the fourth session of the UN negotiations for a global plastics treaty in Ottawa from April 23 to 29. The goal of these meetings is to develop an international legally binding treaty outlining how to deal with the immense problem of plastic pollution. As the fourth meeting is being held in our own backyard, I am especially hopeful and expect the Canadian government to lead the way and propose the strongest commitments on tackling our problems with plastic.
Plastics are everywhere and their integration into our daily lives has been growing exponentially since the 1950s. Almost everything we use has some component of plastic, such as food packaging, toiletries, clothing, furniture, cooking utensils, cutting boards and much more. Currently 460 million tonnes of new plastic are made each year, and production is rising. Global plastic production doubled from 2000 to 2019, and without action, rates of plastic production could further double again by 2040.
Globally, only nine per cent of plastic is recycled and 50 per cent ends up landfills. The rest is incinerated, ends up as litter, or in our oceans. The main problem with plastic is that it doesn't degrade. Whether on land or in the oceans, over time larger plastic pieces break into tiny pieces, commonly called microplastics. In fact, every single piece of plastic that has ever been created is still somewhere on our planet and never goes away.
Plastics have been found on the deepest ocean floors, in our deserts, soils and on the top of the highest peaks in the world. Studies show microplastics as particulate in the air as well.
The effects of accumulating plastics on all ecosystems is well known and visible. What we are learning about more and more, due to growing medical research, is the negative effects of microplastics and plastic additive chemicals on the human body.
Common plastic additives include phthalates, bisphenols and PFAs (polyfluorinated alkyl substances), as well as flame retardants, fillers, colourants and heavy metals.
In 2022, researchers found traces of common synthetic polymers and microplastics in blood samples of human subjects. Plastics are absorbed into the bloodstream, through absorption in the digestive tract, when foods contaminated with plastics are ingested. Studies have also shown the presence of microplastics in human lung tissue. They enter the respiratory system by breathing in air contaminated with plastic particles. This can lead to respiratory diseases such as asthma. From the lungs, microplastics can potentially migrate to other organs and tissues after entrapment by the immune system.
If microplastics can enter our bloodstream, they can potentially reach, and even accumulate, in any organ in the body. In fact researchers have found microplastics in heart tissue samples of patients undergoing heart surgery. Nanoplastics have been found to breach the blood-brain-barrier in mice and then trigger inflammatory cells. In humans, this can cause neurodegenerative disorders such as Parkinson's and Alzheimer's diseases.
What has alarmed me the most is the discovery of microplastics in human placenta samples. Animal studies have shown nanoplastics in the embryonic gut wall of chicks. This indicates that microplastics can cross from the maternal bloodstream into the embryo and affect very early stages of human development. My pregnant patients avoid the consumption of alcohol, drugs and certain prescription medications due to fear of harming the developing fetus. They deserve more information and health warnings about the harms of microplastics or chemical additives on the developing fetus.
Just as concerning is the effect of plastics and additives on the endocrine system, which manages metabolism, reproduction, development and other essential functions. Microplastics and additive chemicals are often called endocrine-disrupting chemicals because they disrupt or imitate hormones within our bodies.
Diseases related to endocrine disrupters include neurodevelopmental disorders such as autism spectrum disorder and attention deficit hyperactivity disorder. Other diseases linked to these chemicals include obesity, type-2 diabetes, infertility, precocious puberty, miscarriage, male infertility and many cancers.
The harms of plastics on human health are an issue of human rights and environmental injustice. The adverse health effects of plastics affect those living in communities near fossil fuel extraction sites or those working in plastic production, due to air and water pollution. In addition to pollution, production of plastic accounts for 3.4 per cent of global greenhouse gas emissions. This doesn't even take into account the GHG emissions from incineration, landfilling, and other waste management practices of plastics. As we know, climate change impacts vulnerable communities
The harms of plastics on human health are an issue of human rights and environmental injustice.
disproportionately, with health impacts from disasters such as wildfires, floods and droughts.
The health harms, injustice and biodiversity loss related to plastic pollution is obvious. We can't wait to act.
We call on the Canadian government to develop national strategies and to lead the international community during the Global Plastics Treaty meetings.
This includes limiting plastic production and expanding reusable alternatives. We need our government to prohibit hazardous chemical additives in plastics and take extra steps to make sure these don't end up in food packaging — including from recycled plastics. Finally, the government must address injustices to front line communities and workers and ensure the right of all people to a clean, healthy and sustainable environment.
If our reliance on plastic is causing harm to the health of our children, then it's time we seriously reconsider the cost of convenience of plastic.