A wave of research has linked microplastics – tiny plastic particles capable of seeping into human tissue – and health problems in recent years, including an increased risk of heart attacks, certain cancers and reproductive problems. Researchers are still working to understand exactly how microplastics affect our health, but newly discovered documents suggest that industry scientists have been aware of the potential risks for decades.
An investigation by the Los Angeles Times obtained internal memos from scientists and chemical company executives revealing that the plastics industry has been aware of and concerned about the possibility of microplastic contamination of the human body for at least 50 years. This revelation comes just two weeks after a study published in Nature found some of the strongest evidence to suggest that microplastics cause biological damage.
“Our results challenge the dominant paradigm of plastic inertia (and) identify a perhaps overlooked mechanism for the adverse health and environmental effects of microplastics,” the authors write in their paper.
Decades of silence
The LA Times investigation found evidence of industry concerns dating back to 1974, when a German scientist named Gerhard Volkheimer presented his research to company and government scientists. His study showed that ingested pieces of PVC (polyvinyl chloride, commonly known as vinyl) plastic can end up in an animal’s bloodstream and then seep into its organs, including the liver, brain, lungs and others, in just two hours.
Volkheimer also fed human subjects potato starch, which moves through the body similarly to PVC, and found it was present in their blood and breast milk. So if potato starch can do this, it’s likely that PVC can do it too.
In the years since the presentation, industry staff have repeatedly referenced the research in internal memos, the Times found. A 1975 letter written by an executive at chemical manufacturer Union Carbide noted that Volkheimer’s study had “often been cited as a ‘horror story’ about ingesting PVC resin.” He contradicted those findings, pointing to a 1947 industry-sponsored study in which animals fed flakes of a PVC-like plastic called Geon 202 did not get sick.
Other documents show that the industry continued to cite Volkheimer’s research throughout the 1970s, 1980s and 1990s, the LA Times reports. Since then, scientists have found ample evidence to support his findings, showing that microplastics can pass from the gut into the bloodstream and accumulate in organs.
The impact of these plastic particles on human health remains an open question, but a growing number of studies point to significant risks.
Evidence of health risks is growing
The Nature paper published earlier this month found evidence suggesting that plastics are not chemically inert once tiny fragments enter the body, contradicting a long-held assumption about their safety.
“As plastic fragments into smaller and smaller particles, its surface area increases enormously,” lead study author Wei Min, a professor of chemistry and biomedical engineering at Columbia University, said in a statement. “Then, microplastics modify the water around them, generating high-energy reactive radicals that most likely contribute to the biological damage we see in animals and potentially in humans following exposure to microplastics.”
Because our bodies are filled with water, it is reasonable to assume that microplastics could create these free radicals, called reactive oxygen species (ROS), inside us. It’s possible that this is the mechanism behind at least some of the health problems linked to microplastics, but to confirm this, more research will be needed.
Tracey Woodruff, a professor of epidemiology and population health at Stanford University who reviewed the documents obtained by the LA Times, told the publication that they indicated that scientists and executives of major chemical companies had long chosen to remain silent about the potential risks of microplastics, but a spokesperson for the chemical industry’s largest trade group disputed that assertion.
“The scientific debate about what the evidence shows is not silence. It’s about how sound science and effective policy move forward,” Craig Davis, senior director of plastics chemistry at the American Chemistry Council, told the LA Times. “Our industry is committed to advancing the science of microplastics by supporting independent research and policies that would contribute to it. »
Plastic is already ubiquitous in our lives, and these dangerous particles have been detected in almost all populations and throughout the human body. In many ways, the damage is done. The question now is how serious will the consequences be?
Gn Health
