It’s raining plastic in the Alps
Plastic rain is now a frighteningly real phenomenon. If you thought acid rain wasn’t bad enough, if you thought we didn’t have enough animal casualties from plastic pollution, think again.
Over the past decade, we’ve seen a huge number of sea animals and whales dying because of the vast quantities of plastic in our oceans. Recently a dead whale surfaced on a beach with plastic filled inside her body.
But as time progresses, the problem is only getting worse.
A new study suggests that it’s raining plastics in the Alps and the Arctic. A large amount of plastic has been found in the snow in these areas. The obvious question is, how do plastics end up in the rain? The answer in one word – microplastics.
What are Microplastics?
Microplastics are smaller versions of plastics that are less than 5 mm (0.2 inch) in length. They have already been detected in seawater, drinking water and in animals. But, the question is how do they get formed and transported to various places as far as the Alps and the Arctic.
Research done by a team of experts from Alfred Wegener Institute, at the Helmholtz Centre for Polar and Marine Research (AWI) suggests that microplastics get transported by the atmosphere and get washed out as rain and precipitation, particularly in the form of snow.
The leaders of the research team, Dr Melanie Bergmann and Dr Gunnar Gerdts analysed snow samples from Helgoland, Bavaria, Bremen, the Swiss Alps and the Arctic. Their observations found that the concentration of microplastic in the snow was very high. Not only in the places located near cities but also in secluded places like the Arctic on the island Svalbard and in snow on drifting ice floes.
How do they reach there?
The hypothesis of the research has been supported by an earlier study conducted on pollen grains. The study on pollen grains had confirmed that they were carried away in atmosphere from the middle latitudes to the Arctic. Pollen grains are of the same size of the microplastics. They also found dust from Sahara getting transported to the northeast Atlantic.
How much microplastic?
The snow from arctic contained around 14,400 particles per litre. A rural road in Bavaria contained 154,000 particles per litre. Both these figures are dangerously high.
Types of Microplastics
These microplastics were found to be parts of nitrile rubber, acrylates and paint. Nitrile rubber is used in gaskets, hoses and has been found to be resistant to various types of fuels. It also has a broad temperature range. Paints that enter the plastic rain cycle are those that are used to coat the surfaces of buildings, ships, cars and offshore oil rigs.
The microplastics found in Bavaria contained various types of rubbers including the one found in automotive tyres.
A matter of concern is the fact that concentration of microplastic found in the study is much higher than the amount found in previous studies.
Why is this increasing so much? One of the team leader, Gunnar Gerdts, says “First of all, snow is extremely efficient when it comes to washing microplastic out of the atmosphere. Secondly, it could be due to the infrared spectroscopy we used, which allowed us to detect even the smallest particles – down to a size of only 11 micrometres.”
The Method of Detection
The team of researchers melted the snow and passed it through a filter. The debris trapped in the filter were then examined using a microscope.
As different plastics respond differently to infrared light, they used it to identify the various plastics found in the snow.
Previous methods used microscopes to find out the nature of the plastics by putting the plastic under the microscope. This made it less accurate and researchers were not able to detect many of the plastics present in the snow.
“We’ve automated and standardised the technique so as to rule out the errors that can creep in when manual analysis is used.” says Gerdts.
Melanie Bergmann, one of the above mentioned team leaders, says “This additional transport route could also explain the high amounts of microplastic that we’ve found in the Arctic sea ice and the deep sea in previous studies.”
She added,“To date there are virtually no studies investigating the extent to which human beings are subject to microplastic contamination.” As most of the researchers focused on how animals or human beings absorb microplastics from what they eat.
Bergmann also said, “But once we’ve determined that large quantities of microplastic can also be transported by air, it naturally raises the question as to whether and how much plastic we’re inhaling. Older findings from medical research offer promising points of departure for work in this direction.”