Microplastics discovered in human heart

7 Sep 2023 by The Water Diplomat

In August, microplastics were found for the first time in human heart tissue. A discovery that is now raising new concerns about their long-term impact on health. A Chinese team discovered the presence of microplastics after examining tissue samples from 15 cardiac surgery patients. The presence of chemicals, such as acrylic or Plexiglas, provides "direct evidence of the presence of microplastics in cardiac surgery patients", although there may be some doubt about contamination during surgery, according to doctors. In several studies, researchers have explained the closed cycle of plastic's transformation until it reaches our plates. The accumulation of microplastics in water presents a diverse range, the main types being polystyrene, polyethylene, polyvinyl chloride and microbeads. Among organisms, his findings indicate that microplastics have been found in the intestinal contents of various mollusc species.

The dominant types of these organisms are polyethylene and PVC. A conclusion confirmed by a researcher in Singh's laboratory. He is currently concentrating on creating a preliminary database on microplastics found in water, sediment and shellfish. Plastic disintegrates into smaller fragments. Pieces of plastic less than five millimeters in size are classified as microplastics. Some are even as small as nanometers. Primary microplastics are tiny particles manufactured for commercial purposes, such as cosmetics, as well as microfibers discarded from clothing, fishing nets and other textiles. Secondary microplastics result from the degradation of larger plastic objects, such as water bottles. When plastic enters ecosystems, it inevitably transforms into microplastics. The smaller its size, the more dangerous it is. Compared to microplastics, nanoplastics can easily penetrate biological cells. 

A danger

A danger to nature and health. On August 17, an article published in The Guardian, based on a new paper by the University of Toronto, revealed that some 90% of water samples taken over the last ten years from the Great Lakes contain levels of microplastics that are dangerous to wildlife. Environmentalists call plastic recycling an "elaborate myth".  The data provided show a higher risk for around 20% of these samples. The Great Lakes provide drinking water for more than 40 million people in the USA and Canada, contain around 90% of the USA's fresh water and are home to 3,500 species of plants and animals. Although there are a myriad of sources of microplastics, wastewater treatment plants appear to be one of the main sources of pollution in the Great Lakes basin, as is the case elsewhere.

Pollution from the microfibres that come off clothes in washing machines is considered another common source. In fact, in 2022, to analyze the presence of microplastics in Jhelum, India, a study conducted by the National Institute of Technology (NIT) in Srinagar and published in the journal Science of the Total Environment examined solid waste disposal sites along rivers. Results: unscientific disposal in landfills along the banks of water bodies is the cause, a common phenomenon in Kashmir and throughout the country, contributing significantly to microplastic pollution.

Microplastics were present in all samples, and their abundance in the water was highest downstream of solid waste disposal sites, according to Muneeb Farooq, researcher at NIT Srinagar and lead author of the study. The same study also shows that, in addition to environmental stresses such as UV exposure, some factors that can contribute to microplastic production are the large local temperature differences between summers and winters. The researchers suggest that when frozen, plastic waste becomes brittle and more vulnerable to degradation under mild environmental pressures.