Microplastics are plastic particles measuring less than five millimetres (0.2 inches).
They have hit the headlines over recent years, as improper disposal has resulted in tonnes of waste making its way into the ocean.
Each year, tonnes of plastic waste fails to get recycled and dealt with correctly, which can mean they end up in marine ecosystems.
Although it’s unclear exactly how they end up in the water, microplastics may enter through simple everyday wear and tear of clothing and carpets.
Tumble dryers may also be a source, particularly if they have a vent to the open air.
Plastics don’t break down for thousands of years and it is estimated that there are already millions of items of plastic waste in the oceans. This number is expected to rise.
Studies have also revealed 700,000 plastic fibres could be released into the atmosphere with every washing machine cycle.
Current water systems are unable to effectively filter out all microplastic contamination, due to the varying size of particles.
The amount of plastic rubbish in the world’s oceans will outweigh fish by 2050 unless the world takes drastic action to further recycle, a report released in 2016 revealed.
More than 80 per cent of the world’s tap water is contaminated with plastic, research published in September 2017 revealed.
The US has the highest contamination rate at 93 per cent, followed by Lebanon and India, experts from the University of Minnesota found.
France, Germany and the UK have the lowest levels, however, they still come in at 72 per cent.
Overall, 83 per cent of water samples from dozens of nations around the world contain microplastics.
Scientists warn microplastics are so small they could penetrate organs.
Bottled water may not be a safer alternative, as scientists have found contaminated samples.
Creatures of all shapes and sizes have been found to have consumed the plastics, whether directly or indirectly.
Previous research has also revealed microplastics absorb toxic chemicals, which are then released in the gut of animals.