All plastic materials that are exposed to the elements will over time disintegrate into smaller and smaller pieces, until they finally end up as microplastics, that is, plastic particles that are less than 5 mm in size. But there are other sources of microplastics as well. Photo: iStock. The Norwegian Environment Agency has surveyed the origins of microplastics. The most important land-based source by far is car tyres. Photo: iStock.

The rogues gallery of microplastics

The Norwegian Environment Agency has surveyed the origins of microplastics. The most important land-based source by far is car tyres.

New knowledge

The Norwegian Environment Agency is publishing three new technical reports on microplastic pollution in marine environments:

The report Sources of Microplastic Pollution to the Marine Environment was written by the consultancy firm Mepex Consult. The report calculates the size of the various sources that directly cause microplastic pollution in Norway.

The report Mikroskräp i avloppsvatten från tre norska avloppsreningsverk (Micro waste in drainage water from three Norwegian drainage facilities) was written by the IVL Swedish Environmental Research Institute. The report studies three drainage facilities in Norway, their purification effect, and the amount of microplastics they discharge.

The report Microplastics in Marine Environments: Occurrence, Distribution and Effects was written by the Norwegian Institute for Water Research (NIVA). The report compares and assesses current knowledge about the scope, spread, and effects of microplastics in marine environments.

Plastic particles less than five millimetres in size are known as microplastics, which have become an ever greater environmental problem.

Animals might think that such plastic particles are food and eat them, resulting in internal injuries, digestion problems, and a false sense of being full.

Plastic particles can also contain toxic substances. Moreover, they absorb environmental toxins from their surroundings. When microplastics are eaten by animals, the toxins may be passed up the food chain – at worst, they may even end up in the food we serve on our plates.

Surveying microplastics

Knowledge is one of the keys to solving the problem. We know that there are many sources of microplastics. Large amounts are generated when plastic waste in the ocean is broken down into ever smaller pieces by the elements, but microplastics are also found as additives to cosmetics and other products.

We need to know more about where microplastics come from and what happens to them. The Norwegian Environment Agency therefore commissioned Mepex Consult to survey the primary land-based sources of microplastic emissions in Norway.

Measures against microplastics and marine pollution

Many voluntary organizations, municipalities, the Norwegian Environment Agency (represented by the Norwegian Nature Inspectorate, SNO), and other public agencies carry own annual clean-up actions along the coast. The environmental authorities also monitor beach waste.

In 2015 the Norwegian Environment Agency is reviewing the list of possible measures in order to assess what steps should be taken. International cooperation will be at the heart of the efforts, since microplastics are dispersed far and wide by the ocean currents.

An element in this work will be to scrutinize the primary sources of microplastic emissions and obtain more knowledge about the damage they cause.

The Storting (the Norwegian parliament) has decided to allot NOK 10 million in the government budget to a separate item for combating marine pollution.

The Norwegian Environment Agency administers these funds and is in the process of drafting allocation criteria, so that calls for funding applications can be announced during the spring.

8,000 tonnes

According to the firm’s report, titled Sources of Microplastic Pollution to the Marine Environment, around 8,000 tonnes of microplastics are generated each year in Norway.

“If you fill central Bergen [pop.: 250,000] with these 8,000 tonnes, the local inhabitants will be up to their knees in microplastics,” says Ellen Hambro, the director general of the Norwegian Environment Agency.

“The report provides us with a first estimate of the amount of microplastics that are emitted in Norway and of where they come from.”

The figures do not include microplastics that are generated when marine pollution decomposes and disintegrates in the ocean.

Tyres and paint

According to the report, by far the largest source is the wear and tear of car tyres, which accounts for around 4,500 tonnes, or approximately half the total emissions. Mepex estimates that around half of the tyre fragments end up in the ocean.

The second largest source stems from the painting and upkeep of ships and pleasure boats. No less than 650 tonnes of the materials related to such activities end up in the ocean as microplastics. The painting and upkeep of buildings represent another significant source, accounting for 310 tonnes that end up in the ocean.

Consumer products

There has been a recent focus on the use of microplastics in cosmetics and similar products, with manufacturers for example adding small plastic particles in order to create an abrasive effect in toothpaste and exfoliants. The problem is that such particles end up in the bathroom drain and hence passed along in the drainage system.

The amount of microplastics that end up in the ocean depends on how effective the purification systems are. The Norwegian Environment Agency asked the IVL Swedish Environmental Research Institute to examine three Norwegian drainage facilities. The resulting report shows that the facilities eliminate between 87 and 97 per cent of the miniscule particles.

According to the Mepex report, microplastics-enhanced cosmetics generate around 40 tonnes of microplastic waste a year in Norway. Around four tonnes of this waste is carried all the way to the sea.

“Cosmetics and toothpaste are not the primary sources of microplastics,” notes Hambro.

“It is nevertheless an area where consumers can make a difference. Last year the Nordic Ecolabel announced that skin care products, soaps, and toothpaste that want to be labelled with the green Swan label must document that they do not contain microplastics. Consumers who buy Swan-labelled cosmetics spare the environment for hazardous plastic particles.”