The millions of tons of plastic swirling around the world’s oceans have garnered a lot of media attention recently. But plastic pollution arguably poses a bigger threat to the plants and animals – including humans – who are based on land.
Very little of the plastic we discard every day is recycled or incinerated in waste-to-energy facilities. Much of it ends up in landfills, where it may take up to 1,000 years to decompose, leaching potentially toxic substances into the soil and water.
Researchers in Germany are warning that the impact of microplastics in soils, sediments and freshwater could have a long-term negative effect on such ecosystems. They say terrestrial microplastic pollution is much higher than marine microplastic pollution – estimated at four to 23 times higher, depending on the environment.
The researchers conclude that, although little research has been carried out in this area, the results to date are concerning: fragments of plastic are present practically all over the world and can trigger many kinds of adverse effects.
The study estimates that one third of all plastic waste ends up in soils or freshwater. Most of this plastic disintegrates into particles smaller than five millimetres, known as microplastics, and these break down further into nanoparticles (less than 0.1 micrometre in size). The problem is that these particles are entering the food chain.
Sewage
Sewage is an important factor in the distribution of microplastics. In fact, between 80 per cent and 90 per cent of the plastic particles contained in sewage, such as from garment fibres, persist in the sludge, says the study. Sewage sludge is often applied to fields as fertilizer, meaning that several thousand tons of microplastics end up in our soils each year. Microplastics can even be found in tap water....ReadMore