A current hot topic is Plastic pollution, there is growing concern surrounding plastic pollution and with good reason, Microplastic has been reported in every major open ocean and many freshwater lakes and rivers (Rochman Et Al, 2015).
What are microplastics and why are they a problem?
The size of plastic pollution (Macroplastic – (>5mm), Microplastic – (<5mm)) (Fendall, 2009) means they are bioavailable to thousands of species across nearly all trophic levels (Rochman Et Al, 2015). Most products that contain microplastics have a size of <100 microns, this means they can be ingested by plankton immediately (Rochman Et Al, 2015), it must be considered that these organisms are at the bottom of the food chain thus these plastics will be transmitted up the food chain. Over time these plastics will be exposed to sunlight and with it they will undergo UV-degradation, this will make them smaller and more toxic in the long term.
Where do they come from?
In the 1990s it was recognised that a source of microplastic pollution was liquid hand-cleansers, this seemed a small problem as these products were rarely used by the average consumer. However, in 2009, microplastic-containing products are much more common in the household as the majority of facial cleansers now contain polyethylene microplastics. These are not captured by wastewater plants and will enter the oceans (Fendall, 2009).
In developed countries, where these products are used much more frequently, waste water goes through several treatment processes. Waste water is sent through settling tanks, within these tanks 95−99.9% of the microbeads may settle out into the sludge (Rochman Et Al, 2015), as a result the final discharge contains fewer than seven microbeads per litre of effluent, this may not sound significant, however an example is that waste water treatment plants in the United States are capable of treating more than 160 trillion litres of water every day (Rochman Et Al, 2015), this water is then discharged directly into habitats.
How can this problem be solved?
There has not yet been proposed a cost-effective efficient clean-up technique, it is for this reason marine scientists need to educate the public to the dangers of using products that pose an immediate and long-term threat to the health of the oceans and the food we eat (Fendall, 2009). Source reduction seems to be the most likely avenue to pursue.
Another option is to return to abrasive materials previously used in these products such as pumice, oatmeal, or walnut husks.
Currently this problem is only getting worse and there are no current cleanup schemes that are working however a ban on microbeads has been imposed in america and the UK will join them in 2017.
Fendall, L. S. (2009). Contributing to marine pollution by washing your face: Microplastics in facial cleansers. Marine Pollution Bulletin, 1225 – 1228.
Free Et Ea, C. M. (2014). High-levels of microplastic pollution in a large, remote, mountain lake. Marine Pollution Bulletin, 156 – 163.
Rochman Et Al, C. M. (2015). Scientific Evidence Supports a Ban on Microbeads. Environmental Science and Technology, 10759 – 10761.