Jeroen Douwes
This is an interesting, albeit small, study suggesting a role for micro and nano plastics (MNPs) in ischaemic heart disease. Despite the large increases in MNP exposure observed since it was first reported 20 years ago, few health studies have been conducted. However, evidence from in vitro and animal models show: inflammatory and other immune responses; oxidative stress; endocrine disruption; cyto-, geno-, and neuro-toxicity; metabolic effects; and gut-microbiota disruption. Emerging clinical studies show associations with cardiovascular disease, stroke, neurodegeneration, neurological symptoms, anxiety and depression. This suggests that MNPs may be a significant and emerging health risk, but research on MNPs and health is still in its infancy and more well-designed and larger studies in human populations are urgently needed.
"This study adds to the emerging evidence that MNP exposure may increase the risk of cardiovascular disease. Previous studies have been criticised for using methods that were not specifically designed to eliminate plastic contamination from sample collection and processing, which the current study addressed, adding to the importance of the study.
"The paper focuses on airborne MNP exposure, and only in passing refers to MNP exposure through diet, which is another significant exposure route that may be at least as important for cardiovascular risk.
"MNPs originate from items (packaging, car tyres, clothing, toys, household products, etc), or are manufactured for use as additives, e.g., to fertilisers, cleaning agents, and personal-care products, and have become ubiquitous in the environment. As a result, they can be detected in food, drinking water, and air, with exposure occurring through ingestion (e.g., via consumption of highly processed foods, reheated foods in plastic containers, bottled drinks, and teabags), inhalation (associated with synthetic clothing, floor coverings, car-tyre wear, and indoor dust), or skin absorption (via personal-care products and synthetic-fibre clothing). So, other exposure routes may be equally or likely more important.
"Due to their small size, MNPs have the potential to migrate through the body, including, as shown in recent studies, the gut, blood, airways, liver, kidney, cerebrospinal fluid, brain, placenta, breast milk, testicles, etc., so health effects will likely not be limited to the cardiovascular system.
"Of interest, in addition to synthetic, mostly oil-derived, polymers, MNPs may contain >16,000 chemical additives, including plasticisers, flame retardants, UV stabilisers, colourants, manganese, other heavy metals, etc, which can leach into surrounding tissue, thus further contributing to health risks, highlighting the need to study the potential health effects that may arise from this new environmental pollutant. This is urgently needed as MNP pollution is rapidly increasing, and currently estimated at 10-40 million tonnes per annum, with an expected doubling of emissions by 2040. If these exposures are, as emerging evidence suggests, causally associated with ill health then we need to start looking at safer options not involving plastics.