"I just want to say one word to you... just one word...Plastics."
One of the many great quotes from the 1967 film “The Graduate” finds the main character, Ben, floundering and undecided as to his future. His future father-in-law tries to guide him and suggests a career in plastics. Over the ensuing 57 years, he certainly would have been proven correct from the business standpoint. Plastics are everywhere. The worldwide production of plastic has grown from less than 2 million tons in 1950 to about 400 million tons in 2020. Plastic production is expected to double by 2040 and triple by 2060. While plastics have made our lives better there is a downside. Plastic waste is ubiquitous in the environment. Plastic bottles, plastic wraps for food and other plastic products are dumped in the ocean and found in the soil. These plastic products break down into smaller particles called microplastics. Microplastics are picked up by fish, especially tuna, oysters, and mussels. The burning of plastics results in the release of microplastics into the air. Humans are exposed to microplastics by ingestion (for example by eating fish) or inhaling air laden with these particles. The Center for Disease Control suggests that microplastics are present in the bodies of nearly all Americans. Microplastics have been found in the colon, liver, spleen and lymph nodes. Now we find out that plastics are present in our arteries.
A study from the March 7 2024 New England Journal of Medicine was eye opening and thought provoking. The researchers examined plaque from patients undergoing surgery for blockage in their carotid (neck) arteries. 304 patients had plaque removed and analyzed. In 58% of patients, microplastics were found in their arteries. Over the next 3 years, the patients who had microplastics in their blood vessels were 4 times more likely to die or have a heart attack or stroke compared to patients without microplastics. The proposed mechanism is that microplastics penetrate the cells in the blood vessel wall, producing chronic inflammation and resulting in worsening plaque production and outcomes. The authors proposed microplastics as a new cardiac risk factor. The study generated lots of discussion in the medical community. The study itself had many flaws (single center, small number of patients). The bottom line is association does not mean causation. Microplastics may be associated with adverse cardiac outcomes but may not be causing the adverse events. Further studies are needed to confirm the findings.
Plastics may be another in a growing number of environmental pollutants that have cardiovascular consequences. Known risk factors are air pollution (http://sportscardiology.blogspot.com/2017/08/paris-polluted-arteries-r-not-in-style.html)
and noise pollution
(http://sportscardiology.blogspot.com/2020/02/the-cardiac-consequence-of-sound.html). Pollution is defined as the presence of a substance in the environment that can cause adverse health effects as well as damage to the ecosystem. Air pollution is the most important environmental cardiac risk factor. Of all of the air pollution related deaths, cardiac disease accounts for 45% of the total, while lung disease is only 8%. In addition, there is soil and water pollution due to farming and industrial activity as well as waste disposal (plastics falls into this category). In addition to plastics, other pollutants include pesticides and heavy metals. Despite different chemical compositions, pollutants lead to cardiovascular disease through common pathways. Pollutants trigger stress reactions leading to systemic inflammation leading to plaque and blockage in arteries, increased blood clotting, and abnormal hormonal secretion.
Controlling pollution is important for overall cardiac health. Decreased air pollution over the past 50 years has contributed to the decline in overall cardiac mortality in that time period. Given the scope and magnitude of the pollution problem, what can a single person do? While most of the heavy work decreasing pollution must be left to governments and industry, there is much the individual can help with. To decrease exposure to air pollution one can stay indoors during high pollutant levels, commute by public transportation or bike or on foot and avoid spending time in high pollution areas, such as near highways. In addition, plastic pollution can be decreased by minimizing single use plastics (products designed for one use and then thrown away). This includes food and beverage containers, bottles, straws, cups, plastic forks and knives and disposable plastic bags. Follow some of these easy measures and your arteries will thank you.