VIDEO: What are microplastics? Here's what you need to know in less than a minute. Transcript
Plastic is the most prevalent type of marine debris found in our ocean and Great Lakes. Plastic debris can come in all shapes and sizes, but those that are less than five millimeters in length (or about the size of a sesame seed) are called “microplastics.”
Microbeads are tiny pieces of polyethylene plastic added to health and beauty products, such as some cleansers and toothpastes.
As an emerging field of study, not a lot is known about microplastics and their impacts yet. The NOAA Marine Debris Program is leading efforts within NOAA to research this topic.
Standardized field methods for collecting sediment, sand, and surface-water microplastic samples have been developed and continue to undergo testing.
Eventually, field and laboratory protocols will allow for global comparisons of the amount of microplastics released into the environment, which is the first step in determining the final distribution, impacts, and fate of this debris.
Microplastics come from a variety of sources, including from larger plastic debris that degrades into smaller and smaller pieces.
In addition, microbeads, a type of microplastic, are very tiny pieces of manufactured polyethylene plastic that are added as exfoliants to health and beauty products, such as some cleansers and toothpastes.
These tiny particles easily pass through water filtration systems and end up in the ocean and Great Lakes, posing a potential threat to aquatic life.
Microbeads are not a recent problem.
According to the United Nations Environment Programme, plastic microbeads first appeared in personal care products about fifty years ago, with plastics increasingly replacing natural ingredients.
As recently as 2012, this issue was still relatively unknown, with an abundance of products containing plastic microbeads on the market and not a lot of awareness on the part of consumers.
On December 28, 2015, President Obama signed the Microbead-Free Waters Act of 2015, banning plastic microbeads in cosmetics and personal care products.
Scientists gather to study risk from microplastic pollution
A blue rectangular piece of microplastic on the finger of a researcher after it was found in debris collected from the Thea Foss Waterway in Tacoma, Wash., in 2010. Scientists say “microplastics” are turning up everywhere in oceans, from the water itself to the guts of fish and the poop of sea otters and giant killer whales. Yet little is known about the effects of these “microplastics” on sea creatures or humans.
Tiny bits of broken-down plastic smaller than a fraction of a grain of rice are turning up everywhere in oceans, from the water to the guts of fish and the poop of sea otters and giant killer whales.
Yet little is known about the effects of these “microplastics” — on sea creatures or humans.
“It's such a huge endeavor to know how bad it is,” said Shawn Larson, curator of conservation research at the Seattle Aquarium. “We're just starting to get a finger on the pulse.”
This week, a group of five-dozen microplastics researchers from major universities, government agencies, tribes, aquariums, environmental groups and even water sanitation districts across the U.S.
West is gathering in Bremerton, Wash., to tackle the issue.
The goal is to create a mathematical risk assessment for microplastic pollution in the region similar to predictions used to game out responses to major natural disasters such as earthquakes.
The largest of these plastic bits are 5 millimeters long, roughly the size of a kernel of corn, and many are much smaller and invisible to the naked eye.
They enter the environment in many ways. Some slough off of car tires and wash into streams — and eventually the ocean — during rainstorms.
Others detach from fleeces and spandex clothing in washing machines and are mixed in with the soiled water that drains from the machine.
Some come from abandoned fishing gear, and still more are the result of the eventual breakdown of the millions of straws, cups, water bottles, plastic bags and other single-use plastics thrown out each day.
Microplastic pollution revealed ‘absolutely everywhere’ by new research
Microplastic pollution spans the world, according to new studies showing contamination in the UK’s lake and rivers, in groundwater in the US and along the Yangtze river in China and the coast of Spain.
Humans are known to consume the tiny plastic particles via food and water, but the possible health effects on people and ecosystems have yet to be determined. One study, in Singapore, has found that microplastics can harbour harmful microbes.
The new analysis in the UK found microplastic pollution in all 10 lakes, rivers and reservoirs sampled.
More than 1,000 small pieces of plastic per litre were found in the River Tame, near Manchester, which was revealed last year as the most contaminated place yet tested worldwide.
Even in relatively remote places such as the Falls of Dochart and Loch Lomond in Scotland, two or three pieces per litre were found.
“It was startling. I wasn’t expecting to find as much as we did,” said Christian Dunn at Bangor University, Wales, who led the work. “It is quite depressing they were there in some of our country’s most iconic locations. I’m sure Wordsworth would not be happy to discover his beloved Ullswater in the Lake District was polluted with plastic.
Welcome to Australia's plastic beach – video
“Microplastics are being found absolutely everywhere [but] we do not know the dangers they could be posing. It’s no use looking back in 20 years time and saying: ‘If only we’d realised just how bad it was.’ We need to be monitoring our waters now and we need to think, as a country and a world, how we can be reducing our reliance on plastic.”
The River Thames in London was found to have about 80 microplastic particles per litre, as was the River Cegin in North Wales. The Blackwater River in Essex had 15. Ullswater has 30 and the Llyn Cefni reservoir on Anglesey 40.
Microplastics have been shown to harm marine life when mistaken for food and were found inside every marine mammal studied in a recent UK survey. They were revealed in 2017 to be in tap water around the world and in October to be consumed by people in Europe, Japan and Russia.
“Microplastic has been found in our rivers, our highest mountains and our deepest oceans,” said Julian Kirby, a plastics campaigner at Friends of the Earth who helped collect water samples for the new UK study. He urged MPs to back legislation “to drastically reduce the flow of plastic pollution that’s blighting our environment”.
Research by the National University of Singapore found more than 400 types of bacteria on 275 pieces of microplastic collected from local beaches. They included bugs that cause gastroenteritis and wound infections in humans, as well as those linked to the bleaching of coral reefs.
Defined as smaller than 5mm in size, microplastics have also been found underground in limestone aquifers in Illinois, US, at a level of 15 particles per litre. This type of groundwater source provides about a quarter of the world’s drinking water.
Other recent studies have found microplastics in bottom-living creatures and sediments taken from the North Sea and the Barents Sea. High concentrations were also foundin the middle and lower reaches of the Yangtze River and along the Mediterranean coast of Spain.
Microplastics are shed by synthetic clothing, vehicle tyres and the spillage of plastic pellets used by manufacturers. The physical breakdown of plastic litter also creates them. Rain washes them into rivers and the sea, but they can also be blown by the wind and end up in fields when treated sewage waste is used as fertiliser.
Kirsten Thompson from the University of Exeter, who is working with Greenpeace on a survey of microplastics in the UK’s major rivers, said: “We hope our research will help uncover exactly where this plastic is coming from and what impact it may be having.”
Microplastics: Your Environment, Your Health | National Library of Medicine
Plastic pieces less than 5 millimeters in size are commonly called microplastics. Microplastics are used in manufacturing, industry, and 3D printing. They are in consumer products such as synthetic clothing fabric, toothpaste, and skincare products.
They are also formed when plastics break apart into tiny beads. When microplastics wash down a drain, they are not removed by wastewater treatment and eventually create problems in the environment. They spread far across and throughout the ocean.
Major sources of microplastics include:
Microplastics are now found everywhere in the ocean and coastal waters, shorelines, ocean seabed, and sea surface.
There is scientific uncertainty about the hazards of microplastic issues. There is concern that microplastics could have adverse health effects on humans as they move through the marine food web.
Microplastics both absorb and give off chemicals and harmful pollutants. Plastic’s ingredients or toxic chemicals absorbed by plastics may build up over time and stay in the environment.
It is not known if you can be exposed to these pollutants by eating contaminated seafood.
You may be at risk if you work:
- At facilities making plastics or products made with plastics
- At waste management, wastewater treatment, or aquaculture facilities
- On a cruise ship
- In the shipping or fish farming industries
You may also be exposed if you:
- Use certain toothpaste or skincare products with plastic microbeads
- Visit shorelines
- Go in the ocean or coastal waters
- Do you use plastic bottles or containers?
- Minimize use of consumer products that might contain microplastics.
- Choose paper bags over plastic bags and glass products over plastic ones.
- Recycle plastics to help prevent introducing more microplastics in the environment.
- Never throw plastic items in lakes, rivers, oceans, or other bodies of water.
- Great Pacific Garbage Patch National Geographic Society An encyclopedic entry on the Great Pacific Garbage Patch, also known as the Pacific trash vortex, a collection of marine debris, including microplastics, in the North Pacific Ocean, and efforts to clean it up.
- Toxicological Threats of Plastic Environmental Protection Agency Information on hazardous plastic pollution in the marine environment and the dangers of microplastics in water.
- What are microplastics? National Oceanic and Atmospheric Administration Information and a short video on what are microplastics and how they can be dangerous to ocean and aquatic life.
- New Link in the Food Chain? Marine Plastic Pollution and Seafood Safety National Institute of Environmental Health Sciences Information about plastic pollution in the ocean, and the health effects from associated toxic exposure to people who eat seafood, from a federal institute that investigates the interplay between environmental exposures, human biology, genetics, and common diseases to help prevent disease and improve human health.
Microplastic pollution is everywhere, but scientists are still learning how it harms wildlife: U of T experts
Plastic pollution is a growing global concern. Large pieces of plastic have been found almost everywhere on Earth, from the most visited beaches to remote, uninhabited islands. Because wildlife are regularly exposed to plastic pollution, we often ask what effects plastics have on the animals.
Over time, macroplastics (plastic debris larger than five millimetres in size) break up into tiny particles called microplastics (smaller than five millimetres), which can persist in the environment for hundreds of years.
Macroplastics are known to cause detrimental effects for wildlife. Individual animals can ingest large pieces or become entangled in plastic items, such as fishing gear, and suffocate or starve to death. Although there is no question that macroplastics are harmful to wildlife, the effects of microplastics are not as straightforward.
While many studies find microplastics can affect the gene expression, growth, reproduction or survival of an animal, others conclude that microplastics have no negative effects. The lack of clear consensus makes it more difficult for decision-makers to enact effective policies to mitigate plastic pollution.
Not all plastics are the same
We recently took a deep dive into the research that has looked at how plastic pollution affects aquatic and terrestrial wildlife.
We found that while macroplastics continue to cause detrimental effects to individual animals, they are also causing larger-scale changes to populations of animals, communities and ecosystems.
For example, plastic pollution can introduce invasive species to new habitats by transporting organisms hundreds of kilometres from their native range, changing the composition of species in a community.
The effects of microplastics, however, are much more complicated. Of the studies we included in our review, nearly half (45 per cent) found that microplastics caused an effect.
Some studies saw that microplastics caused animals to have shorter lives, eat less or swim slower, and others saw changes in the number of offspring produced, and changes in the genes being expressed.
Yet, 55 per cent of the studies didn’t detect any effects.
Why do some studies detect effects while others do not? There are several possibilities. For one, the researchers used different experimental designs in their lab experiments.
There’s also the issue of using the term microplastics, which refers to a complex mixture of plastics that vary in material (such as polyethylene, polystyrene or polyvinyl chloride), the chemicals associated with them (including additives, fillers and dyes), as well as their size and shape. Each of these characteristics, along with how much plastic the animal is exposed to in the experiment, could affect their potential to detect an effect.
Microfibres and microbeads
For example, we saw that when studies exposed crustaceans to polystyrene, a type of plastic used to make disposable containers, lids and cutlery, the crustaceans generally produced more offspring. But when they were exposed to polyethylene or polyethylene terephthalate, which is used to make plastic bags and beverage bottles, the crustaceans produced fewer offspring.
Very small pieces of plastic that pollute the environment
Microplastics in sediments from rivers
Microplastics are very small pieces of plastic that pollute the environment. Microplastics are not a specific kind of plastic, but rather any type of plastic fragment that is less than 5 mm in length according to the U.S. National Oceanic and Atmospheric Administration (NOAA). They enter natural ecosystems from a variety of sources, including cosmetics, clothing, and industrial processes.
Two classifications of microplastics currently exist. Primary microplastics are any plastic fragments or particles that are already 5.0 mm in size or less before entering the environment. These include microfibers from clothing, microbeads, and plastic pellets (also known as nurdles).
 Secondary microplastics are microplastics that are created from the degradation of larger plastic products once they enter the environment through natural weathering processes. Such sources of secondary microplastics include water and soda bottles, fishing nets, and plastic bags.
 Both types are recognized to persist in the environment at high levels, particularly in aquatic and marine ecosystems.
Additionally, plastics degrade slowly, often over hundreds if not thousands of years. This increases the probability of microplastics being ingested and incorporated into, and accumulated in, the bodies and tissues of many organisms. The entire cycle and movement of microplastics in the environment is not yet known, but research is currently underway to investigate this issue.
Microplastic fibers identified in the marine environment
Photodegraded plastic bag adjacent to hiking trail. Appx 2,000 pieces 1 to 25 mm. 3 months exposure outdoors.
The term “microplastics” was introduced in 2004 by Professor Richard Thompson, a marine biologist at the University of Plymouth in the United Kingdom.
Microplastics are common in our world today. In 2014, it was estimated that there are between 15 and 51 trillion individual pieces of microplastic in the world's oceans, which was estimated to weigh between 93,000 and 236,000 metric tons.
Polyethylene based microspherules in toothpaste
a) Artificial turf football field with ground tyre rubber (GTR) used for cushioning. b) Microplastics from the same field, washed away by rain, found in nature close to a stream.
Primary microplastics are small pieces of plastic that are purposefully manufactured. They are usually used in facial cleansers and cosmetics, or in air blasting technology. In some cases, their use in medicine as vectors for drugs was reported. Microplastic “scrubbers”, used in exfoliating hand cleansers and facial scrubs, have replaced traditionally used natural ingredients, including ground almonds, oatmeal, and pumice. Primary microplastics have also been produced for use in air blasting technology. This process involves blasting acrylic, melamine, or polyester microplastic scrubbers at machinery, engines, and boat hulls to remove rust and paint. As these scrubbers are used repeatedly until they diminish in size and their cutting power is lost, they often become contaminated with heavy metals such as cadmium, chromium, and lead. Although many companies have committed to reducing the production of microbeads, there are still many bioplastic microbeads that also have a long degradation life cycle similar to normal plastic.
Secondary plastics are small pieces of plastic derived from the breakdown of larger plastic debris, both at sea and on land.
Over time, a culmination of physical, biological, and chemphotodegradation, including photodegradation caused by sunlight exposure, can reduce the structural integrity of plastic debris to a size that is eventually undetectable to the naked eye.
 This process of breaking down large plastic material into much smaller pieces is known as fragmentation.
 It is considered that microplastics might further degrade to be smaller in size, although the smallest microplastic reportedly detected in the oceans at present is 1.6 micrometres (6.3×10−5 in) in diameter. The prevalence of microplastics with uneven shapes suggests that fragmentation is a key source.
Other sources: as a by-product/dust emission during wear and tear
There are countless sources of both primary and secondary microplastics. Microplastic fibers enter the environment from the washing of synthetic clothing.
 Tires, composed partly of synthetic styrene-butadiene rubber, will erode into tiny plastic and rubber particles as they are used. Furthermore, 2.0-5.
0 mm plastic pellets, used to create other plastic products, often[quantify] enter ecosystems due to spillages and other accidents.
A Norwegian Environment Agency review report about microplastics published in early 2015
states it would be beneficial to classify these sources as primary, as long as microplastics from these sources are added from human society at the “start of the pipe”, and their emissions are inherently a result of human material and product use and not secondary defragmentation in nature.
Depending on the definition used, nanoplastics are less than 1 μm (i.e. 1000 nm) or less than 100 nm in size. The existence of nanoplastics in the environment is under debate since detection, and quantification in environmental matrices remains a challenge.
Speculations over nanoplastics in the environment range from it being a temporary byproduct during the fragmentation of microplastics to it being an invisible environmental threat at potentially high concentrations.
The presence of nanoplastics in the North Atlantic Subtropical Gyre has been confirmed and recent developments in Raman spectroscopy and nano-fourier-transform infrared (nano-FTIR) technology are promising answers in the near future regarding the nanoplastic quantity in the environment.
Nanoplastics are thought to be a risk to environmental and human health. Due to their small size, nanoplastics can cross cellular membranes and affect the functioning of cells. Nanoplastics are lipophilic and models show that polyethylene nanoplastics can be incorporated into the hydrophobic core of lipid bilayers.
 Nanoplastics are also shown to cross the epithelial membrane of fish accumulating in various organs including the gall bladder, pancreas, and the brain. Little is known on adverse health effects of nanoplastics in organisms including humans.
In zebrafish, polystyrene nanoplastics can induce a stress response pathway altering glucose and cortisol levels, which is potentially tied to behavioral changes in stress phases.
The existence of microplastics in the environment is often established through aquatic studies. These include taking plankton samples, analyzing sandy and muddy sediments, observing vertebrate and invertebrate consumption, and evaluating chemical pollutant interactions. Through such methods, it has been shown that there are microplastics from multiple sources in the environment.
Microplastics could contribute up to 30% of the Great Pacific Garbage Patch polluting the world's oceans and, in many developed countries, are a bigger source of marine plastic pollution than the visible larger pieces of marine litter, according to a 2017 IUCN report.
Sewage treatment plants
Sewage treatment plants, also known as wastewater treatment plants (WWTPs), remove contaminants from wastewater, primarily from household sewage, using various physical, chemical, and biological processes.
 Most plants in developed countries have both primary and secondary treatment stages. In the primary stage of treatment, physical processes are employed to remove oils, sand, and other large solids using conventional filters, clarifiers, and settling tanks.
 Secondary treatment uses biological processes involving bacteria and protozoa to break down organic matter. Common secondary technologies are activated sludge systems, trickling filters, and constructed wetlands.
The optional tertiary treatment stage may include processes for nutrient removal (nitrogen and phosphorus) and disinfection.
Microplastics have been detected in both the primary and secondary treatment stages of the plants. A groundbreaking 1998 study suggested that microplastic fibers would be a persistent indicator of sewage sludges and wastewater treatment plant outfalls.
 A study estimated that about one particle per liter of microplastics are being released back into the environment, with a removal efficiency of about 99.9%. A 2016 study showed that most microplastics are actually removed during the primary treatment stage where solid skimming and sludge settling are used.
 When these treatment facilities are functioning properly, the contribution of microplastics into oceans and surface water environments from WWTPs is not disproportionately large.
Sewage sludge is used for soil fertilizer in some countries, which exposes plastics in the sludge to the weather, sunlight, and other biological factors, causing fragmentation. As a result, microplastics from these biosolids often end up in storm drains and eventually into bodies of water.
 In addition, some studies show that microplastics do pass through filtration processes at some WWTPs (Microplastics as Contaminants, 2011). According to a study from the UK, samples taken from sewage sludge disposal sites on the coasts of six continents contained an average one particle of microplastic per liter.
A significant amount of these particles was of clothing fibers from washing machine effluent.
Car and truck tires
Wear and tear from tires significantly contributes to the flow of (micro-)plastics into the environment. Estimates of emissions of microplastics to the environment in Denmark are between 5,500 and 14,000 tonnes (6,100 and 15,400 tons) per year.
Secondary microplastics (e.g. from car and truck tires or footwear) are more important than primary microplastics by two orders of magnitude.
The formation of microplastics from the degradation of larger plastics in the environment is not accounted for in the study.