‘Plastic pollution’, like ‘climate change’, seems to have become an environmental dirty phrase that makes people instantly bored.
Unlike climate change, however, whose impact it may be challenging to relate to directly, there is nothing distant about finding discarded plastic at your feet in any rural location you visit.
This is especially the case with marine plastic pollution, and I, for one, did not manage to find a single plastic-free beach over the past year (I really tried).
Alongside the easily noticeable objects (cups, bottles, tyres), consider the less obvious (such as small plastic pellets or ‘nurdles’), or the barely visible (fragments and fibres – collectively known as microplastics), and it follows that plastic pollution probably covers most of the globe.
Increased awareness of the vast presence of miniscule pieces of plastic in the environment is leading to the establishment of specialised research campaigns in an attempt to understand the effects of this ubiquitous material.
The problem with plastic pollution, besides it being unsightly and costly to clear up, is that it has found its way absolutely everywhere, including our food and water sources, as revealed by recent investigations.
However, the fairly short-lived existence of plastic in our daily lives, beginning roughly in the 1940s, implies that we are not yet experiencing the full effects it may have on both the natural environment and our personal health.
Although we are well aware of the physical harm that plastic debris can cause to wildlife, such as entanglement and asphyxiation, with decreasing debris size comes decreasing knowledge.
While we understand that species can be transported on floating pieces of plastic and become invasive in their new environments, there is much left to learn concerning the role that microplastics play as vectors of persistent, bioaccumulating, toxic contaminants.
Microplastics are minute pieces of plastic, generally agreed to be smaller than 5mm in diameter, although a universal definition does not yet exist – a feature telling of the early stages of this field of scientific research.
They can either come from larger plastic items which break down (secondary microplastics) or be manufactured at this size (primary microplastics). The latter category is largely made up of tiny resin pellets or microbeads which serve as exfoliants in cosmetic products and are also found in toothpaste.
Due to their miniscule size, these particles have a very large surface area to volume ratio, making them ideal vectors of contaminants, which can attach and release themselves from the plastic through a reversible process.
Dichlorodiphenyltrichloroethane (DDT), for example – banned entirely in the UK in 1984 and banned for agricultural use in the USA in 1972 – is still used in some parts of the world as a means to control malaria, and can find its way into our plates through such a process.
The microplastics’ size allows them to pass through water filtration systems, making them almost impossible to keep out of lakes and seas, where they are easily ingested by fish which we may be eating.
Sources and Bans
In fact, it is believed that 80% of the plastic that ends up in the sea comes from sources on land, due to poor waste management.
In terms of nurdles, an estimated 53 billion of these small plastic pellets find their way into the natural environment each year; in Europe alone, up to 230,000 tonnes of plastic may be entering the ocean each year; in the UK, plastic cotton bud stems are the most common litter found on beaches.
Action has already been taken in the form of bans, such as the Microbead-Free Water Act of 2015 signed by Obama, and similar bans on microbeads in personal care products are under consideration in Canada, Australia, the UK, Ireland and France.
Furthermore, several companies have converted to non-plastic stems for their cotton buds, including Johnson & Johnson, Marks & Spencer, and The Body Shop, with several more stating they will soon follow this trend.
Why biodegradable plastic/alternatives aren’t a solution
Indeed, biodegradable plastics have been developed, and when they do truly biodegrade into carbon dioxide, water and inorganic molecules, this is a great solution.
Unfortunately, specific conditions are required for this break-down to take place.
While landfills and industrial composters provide suitably high temperatures and have the necessary microbes present, this is not the case when plastic finds its way into oceans. In such less than ideal conditions, the best result is to have a big piece of plastic break down into many microplastics, and this is no solution at all.
Looking at environmentally-friendly alternatives to plastic, such as steel, glass, aluminium and paper, it appears that the environmental cost is much the same.
The production and consumption of plastic is more harmful when compared to the same amount of alternative materials; nevertheless, approximately four times more alternative material is needed to perform the same function as plastic, so this initial advantage is easily offset.
True improvements would involve more efficient and sustainable designs to minimise the use of plastic followed by better waste management and disposal.
Campaigns and Research
Although disturbing figures are already emerging, the young life of microplastics research still has a long way to go in providing standardised methods and collecting sufficient data to allow comparisons in space and over time.
At present, dedicated research teams do exist and range from special advisory bodies to the UN with the establishment of the Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP) in collaboration with representatives of the plastic industry in late 2011, to citizen-based surveys sponsored by charities, such as seasonal ‘nurdle hunts’ in the UK organized by Scottish charity Fidra.