With the body of research on microplastics now growing across the globe, researchers warned that the latest studies on the health issue are already showing that the impacts are very concerning and it could pose serious problems in the future.

According to Tracey Woodruff, a researcher at the University of California in San Francisco, a systematic review of 2,000 previous studies on animals found that microplastics “can harm fertility and are linked to increased cancer risk while harming respiratory health.”

“It is a ‘red flag’ that microplastics have been found in so many areas of the body, including the brain, testes and even crossing the placenta into the fetus,” Woodruff noted.

“Many of the most worrying studies, such as the one from March, have been observational. This means they cannot prove microplastics are directly causing the health problems they have been linked to,” she added.

She explained that “data from animals has been used to identify carcinogens and reproductive toxicants for decades”

However, the UC researcher pointed out that many things remain unknown about how microplastics could affect health, including the role played by their size, shape and composition.

“Many plastics are a complex cocktail of polymers and chemicals and there are fears they could smuggle in other contaminants in what is called the ‘Trojan Horse’ effect.

Woodruff’s findings are corroborated in other studies that cite microplastics having been found throughout the human body, including inside the lungs, blood and brains, and while it is not yet clear how harmful they are to human health, researchers are sounding the alarm.

“These tiny pieces of plastic have been detected almost everywhere on Earth, from the deepest oceans to the highest mountains, as well as in the air, water, soil and food chain. Every day humans ingest, inhale, or otherwise come in contact with microplastics, which are less than 5 millimeters (0.2 inches) and mostly invisible to the naked eye,” French specialist researcher Fabienne Lagarde.

At the French parliament, Lagarde disclosed that “a human in 2024 has plastic in almost all the organs of their body . . . and it will probably be even worse for the children born in 2040.”

Numerous studies, she said, have linked the presence of microplastics—or nanoplastics, which are 1,000 times smaller—to a range of health problems.

In March, a study in the New England Journal of Medicine found an association between microplastics accumulating in people’s blood vessels and an increased risk of heart attack, stroke or even early death.