Microplastics in the oceans, air and human body

From the depths of the oceans to the mountaintops, humans have littered the planet with tiny shards of plastic. We have even ingested this microplastic into our bodies – with uncertain effects.

Images of plastic pollution have emerged: a turtle being smothered by a grocery bag, water bottles washing up on beaches, or the monstrous “Great Pacific Garbage Patch” of floating garbage.

Millions of tons of plastic, produced primarily from fossil fuels, are released into the environment each year and break down into smaller and smaller pieces.

“10 years ago we could not have imagined that there could be so many small microplastics that are invisible to the naked eye and that they are all around us,” said Jean-Francois Ghiglione, a researcher at the Laboratory of Microbial Oceanography in France.

“And we couldn’t imagine finding them in the human body yet.”

Now scientific studies are increasingly showing evidence of microplastics in some human organs – including “lungs, spleen, kidneys and even the placenta,” Ghiglione told AFP.

It may not come as a shock that we breathe these airborne particles, especially microfibers from synthetic clothing.

“We know microplastics are in the air, we know they’re all around us,” said Laura Sadofsky of Hull York Medical School in the UK.

Her team found polypropylene and PET (polyethylene terephthalate) in lung tissue and identified fibers made from synthetic fabrics.

“The surprise for us was how deep it got into the lungs and how big these particles were,” she told AFP.

In March, another study reported the first traces of PET in the blood.

Given the small sample of volunteers, some scientists say it’s too early to draw any conclusions, but there are concerns that if plastics get into the bloodstream, they could be transported to all organs.

In 2021, researchers found microplastics in both maternal and fetal placental tissue and expressed “great concern” about the potential consequences for fetal development.

But concern is not the same as a proven risk.

“If you ask a scientist if there is a negative effect, he or she would say, ‘I don’t know,'” said Bart Koelmans, professor of aquatic ecology and water quality at Wageningen University.

“It’s potentially a big problem, but we don’t have the scientific evidence to positively confirm the effects, if any.”

One hypothesis is that microplastics could be responsible for certain clinical pictures that weaken human health.

While scientists have recently identified their presence in the body, it’s likely that people have been eating, drinking, and breathing in plastics for years.

In 2019, a shock report from environmental organization WWF estimated that people ingest and breathe in up to five grams of plastic a week — enough to make a credit card.

Koelmans, who disputes the methodology and results of this study, has calculated that the amount is closer to a grain of salt.

“In life, a grain of salt a week is still a lot,” he told AFP.

While human health studies have yet to be developed, toxicity in certain animals adds to concerns.

“Small microplastics that are not visible to the naked eye have harmful effects on all animals that we have studied in the marine environment or on land,” Ghiglione said.

He added that the array of chemicals found in these materials – including dyes, stabilizers, flame retardants – can affect growth, metabolism, blood sugar, blood pressure and even reproduction.

The researcher said there should be a “precautionary” approach and urged consumers to reduce the number of plastic-packaged products they buy, particularly bottles.

Earlier this year, the United Nations launched a process to develop an internationally binding agreement to tackle the global plastic plague.

It has warned that the world is facing a pollution crisis to match the biodiversity and climate crisis.

While the health effects of plastics are unknown, scientists do know the effects of indoor and outdoor air pollution, which experts at the Lancet Commission on Pollution and Health estimated caused 6.7 million people to die in 2019 early have suffered death.

Around 460 million tons of plastics were used in 2019, twice as much as 20 years earlier. Less than 10 percent was recycled.

Annual production of fossil fuel-based plastics is projected to top 1.2 billion tons by 2060, with waste topping 1 billion tons, the Organization for Economic Co-operation and Development said last month.

“People can’t stop breathing, so even if you change your eating habits, you’re still going to breathe them in,” Koelmans said.