As the federal government plans its counterattack against opponents of its single-use plastic ban, the battle to reverse the health and environmental hazard posed by microplastics – plastic debris less than five millimetres in size – continues globally, and here in Canada.
The same day the Supreme Court overturned the cabinet order classifying plastic items as toxic, effectively overturning the ban on single-use plastics, EarthDay.org released a new report, Babies vs Plastic, summarizing research on microplastics in early childhood. Microplastics have been detected in all physical environments, from the oceans to the Arctic, but also in reproduction, starting with conception. Research suggests that microplastics may impact fertility; even sex toys contribute to exposure.
Beyond fetal and neonatal exposure, early childhood is a time of high risk of exposure. Microplastics can be detected at various levels in placentas, breastmilk, infant formula and meconium (newborn poop). Toddlers put everything in their mouths, exposing them to microplastics, especially in commonly used items like pacifiers, bottles and neighbourhood playground structures.
Microplastics come from plastic in manufacturing; the disintegration of products such as shopping bags produce secondary microplastics. Both break into tiny pieces, entering our water, air and soil – and our bodies. Small animals ingest microplastics, mistaking them for food, and pass them into the human food chain. Microplastics can then break down into microscopic pieces called nanoplastics. Though less well studied, nanoplastics’ microscopic size could allow them to more easily bypass cellular structures such as the blood-brain barrier.
Two factors increase the risk of toxicity for ecosystems and human health. The first comes from additives in plastics to add properties such as flexibility. Research has forced changes in regulation as health risks from exposure to plastic additives like phthalates and bisphenol A (BPA) are identified. The second risk comes from the ability of microplastics to accumulate and carry contaminants. For example, landfills contain numerous chemicals and biohazards that cling to microplastics.
George Kitchling, a family doctor and a member of Canadian Association of Physicians for the Environment, calls exposure to microplastics a threat. “Certainly, you know, smoking one cigarette is not going to kill you. But we know that smoking cigarettes causes lung cancer and [could] kill you. So, this is something similar.”
Environment and Climate Change Canada and Health Canada are responding with a report on microplastics in Canada, slated for publication next year. The report is expected to discuss the occurrence of microplastics, their effects on human health and the environment, and the methods used in research. Government funding has been allocated to find innovative ways to reuse plastic, including those that are hard to recycle. Still, cultural shifts are challenging for consumerist societies, where it is easy, cheap and convenient to throw items away after a single use.
Sabina Halappanavar, a scientist at Health Canada studying microplastics in the air, says her team wants to learn more about how exposure to microplastics impacts health. She says that microplastics research is in its early stages, with teams working on learning about their diverse characteristics – their shape, size, how they enter our bodies and in what amounts.
“Knowing there is microplastics in the air that comes from a disposable plastic water bottle, in the lab we have prepared microplastics from plastic water bottles. And then we have exposed cells to the microplastics to see their response,” says Halappanavar.
“There’s no escaping some form of exposure.”
“… Using cell models, yes, some of them do induce certain types of toxicity. Some of them induce cell death. Some of them induce pro-inflammatory mediators – meaning if you were to inhale them, possibly, it may cause inflammation reactions in your lungs,” she says of the preliminary findings. For now, acute effects on human health are not clear.
Microplastics can also seep into the environment during recycling, water treatment and wastewater processing. This means that microplastics may be re-distributed to new environments. Either way, there’s no escaping some form of exposure.
“Removing microplastics is going to be incredibly challenging,” says Ryan Prosser, a professor in environmental toxicology at the University of Guelph. “I think our best hope is focusing our attention on cutting our use of plastic.”
While his team continues to study exposure on marine life, and levels leading to toxicity, Prosser emphasizes the root of the problem: widespread plastic use and poor waste management systems.
For the most part, microplastics in drinking water are removed through processes already in place to remove contaminants. Water treatment is strictly regulated for consumer safety, with processes and regulations in place to remove toxins and particles from drinking water. Additional treatment with coagulants helps particles in water stick together, making it easier to remove. However, more pollution could result in toxicity from exposures in drinking water, Husein Al-Muhtaram, a researcher at the Drinking Water Research Group (DWRG) warns.
“The percentage removal may be the same. But you can imagine 99 per cent removal of 100 particles gives you one particle, but 99 per cent removal of a thousand particles gives you 10 particles,” says Al-Muhtaram. “The more there is to begin with in the source water, the more that you will have in the finished water, and that range is very, very wide, depending on what the sources are. And I’m talking about studies that have been conducted around the world.”
The team of researchers based at the University of Toronto is collaborating with industry and governments to study microplastic levels and improve removal from drinking water. It also has been working with teams in California, where policies are being implemented to test microplastic levels in water. California has become a leader in regulating microplastics and is researching their impacts on human health. This year, monitoring will be implemented in 27 water systems in the state, the first time that any government, anywhere in the world, will require monitoring specifically for microplastics in drinking water.
