Your contact lenses become plastic litter every time you f lush them down the loo
CONTACT lenses are threatening marine life because they can turn into harmful microplastics, scientists are warning.
Nearly 14% of the Irish public wear contact lenses, according to the online statistics consultancy, Statista.
But the lenses become plastic litter when flushed down the toilet or washed down the sink.
US chemists found that five polymers used in the lenses lose their structural strength when exposed to common microbes found in water treatment plants.
They say this could break them down into microplastics that make their way into the sea to be swallowed by fish, which mistake them for food.
This, in turn, has led to fears that the human food chain could be contaminated.
The Irish Daily Mail has campaigned against plastic waste and for a ban on the plastic microbeads used in face scrubs, toothpaste and shower gels. But up to one in five people still flush contact lenses down the sink or toilet, nationwide research in the US found.
Dr Rolf Haden, from Arizona State University, who co-authored the study, said: ‘I had worn glasses and contact lenses for most of my adult life.
‘But I started to wonder, has anyone done research on what happens to these plastic lenses?’
Researchers then exposed five polymers used in daily disposable lenses to anaerobic and aerobic micro-organisms found in water treatment plants. The results, to be presented at the annual meeting of the American Chemical Society, show the lens surfaces became weakened.
Varun Kelkar, from the university’s Biodesign Institute, said: ‘We found there were noticeable changes in the bonds of the contact lenses after longterm treatment with the plant’s microbes.
‘When the plastic loses some of its structural strength, it will break down physically. This leads to smaller plastic particles which would ultimately lead to the formation of microplastics.’
Contact lenses, like cotton buds, are very hard to remove from sewage because they can squeeze through screens and pass through the whole treatment process before ending up in the waste water that flows into rivers or seas.
Contacts tend to be denser than water so they sink, posing a threat to bottomfeeding marine animals that mistake microplastics for food.
The indigestible fragments fill their stomachs so they may die of starvation.
The researchers want labels on contact lens packets to tell users how to dispose of them properly.
The European Union is close to passing a new law to ban many types of single-use plastics, including straws, sticks for holding balloons and many types of fishing tackle.
Contact lenses are not included in the list, which also includes plastic plates, plastic utensils, plastic coffee stirrers and cotton swabs with plastic stems.
The draft directive also restricts the use of plastic cups and plastic packaging used by the take-away industry, and urges member states to set clear goals for plastic reduction.
The European Commission intends to get the draft approved by EU member
Fish can mistake the microplastics for food
states and the European Parliament before the end of May 2019, and members are asked to introduce domestic laws within about two years after.
European states have led the world in restricting the use of plastic shopping bags. In 2002, Ireland became the first country in the world to introduce a tax on shopping bags. The measure spread to other European Union countries and the EU aims by next year to have cut plastic shopping bags by 80% from 2010 levels.
The products that face restrictions make up 70% of plastic waste washed up on European beaches.