Introduction:
Worldwide, cardiovascular disease continues to be the primary cause of mortality despite advancements in medical prevention and treatment. Reducing the incidence of cardiovascular disease and associated mortality has depended mainly on the identification of risk factors, such as diabetes, hypertension, dyslipidemia, physical inactivity, and tobacco use. Understanding these risk factors has improved early identification, raised public awareness of cardiovascular disorders, and directed prevention and treatment.
Another significant but sometimes disregarded risk factor for cardiovascular disease is environmental pollution. According to the Global Burden of Disease (GBD) study, 9 million fatalities globally occurred in 2019 as a result of pollution, with cardiovascular disease accounting for 61.9 % of those deaths. Lowering exposure to these environmental toxins is crucial for reducing pollution-related health problems. To assist in preventing ecological toxins, this article will offer insights into their sources.
How Does Environmental Pollution Impact Cardiovascular Health?
Air Pollution:
Global health is significantly impacted by ambient air pollution, which includes particulate matter (PM) and gaseous pollutants such as nitrogen oxides, carbon monoxide, and sulfur dioxide. The average life expectancy is lowered by 2.9 years, and the causes of almost 50 % of the excess fatalities are linked to diabetes, hypertension, ischemic heart disease, and cardiovascular disorders. PM, especially PM2.5 (particles ≤2.5 µm), is a significant contributor to cardiovascular risk and is produced by burning fossil fuels, manufacturing operations, and vehicle emissions.
Atherosclerosis, coagulation, thrombosis, arrhythmias, hypertension, and endothelial dysfunction are all associated with PM2.5 exposure. While long-term exposure is linked to chronic atherosclerosis, short-term exposure can cause an acute myocardial infarction. According to research on animals, PM2.5 affects cardiovascular health by causing oxidative stress, inflammation, and disruption of circadian rhythms.
Globally, wildfires have increased PM2.5 exposure due to climate change, which has resulted in a considerable increase in cardiovascular morbidity and mortality. The detrimental consequences of air pollution on cardiovascular health are further highlighted by the fact that contaminants, including nitrogen oxides, ozone, and volatile organic compounds (VOCs), also play a role in these detrimental effects.
Climate Change:
One major global threat from climate change is the development of environmental risks that influence cardiovascular health. In addition to the air pollution caused by wildfires, the health effects of climate change, specifically temperature variations, are directly linked to cardiovascular disease. Hot and cold temperatures are some of the most immediate dangers. After breaking global heat records in 2022, the planet saw its highest temperatures in over 100,000 years in 2023. Elevated temperatures increase the risk of cardiovascular death resulting from heart failure, stroke, and ischemic heart disease. In a similar vein, excessive cold increases these dangers.
According to physiological principles, cold causes vasoconstriction and hypertension, whereas high temperatures result in dehydration, an elevated heart rate, and sympathetic activity. Due to age-related changes in the circulatory system and a higher prevalence of underlying illnesses, older persons are more vulnerable. Psychological stress brought on by climate change worsens cardiovascular outcomes, disproportionately affecting underprivileged groups. Forecasts suggest that if extreme weather events become more common and severe, the number of extra cardiovascular deaths caused by climate change will rise, particularly among older persons and non-Hispanic Black populations.
Noise and Light Pollution:
Cardiovascular and metabolic illnesses are becoming more closely associated with light and noise pollution. Studies using epidemiological methods have connected traffic noise to higher rates of cardiovascular illness and death. When this noise activates the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis, stress hormones like cortisol and catecholamines are released. These hormones can worsen hyperglycemia, hypercholesterolemia, and hypertension. Adiposity indicators and obesity have been linked to prolonged exposure to noise. According to research on animals, noise exposure causes oxidative stress, inflammation, endothelial dysfunction, and chronically elevated blood pressure, all of which are atherosclerosis factors.
Another effect of noise is disturbed sleep, which raises the risk of cardiovascular disease. Both conventional (such as obesity and hypertension) and unconventional (such as sleep disturbance) risk factors are involved in the cardiovascular consequences of noise. Furthermore, a lot of light at night disturbs circadian cycles, raising cardiovascular risk. Research has revealed links between obesity, hypertension, preclinical atherosclerosis, and light pollution. The effects of continuous light exposure on animal models show that brown adipose tissue is reduced and body fat is increased, underscoring the need for more research on the effects of light pollution on heart health.
Per- And Polyfluoroalkyl Substances:
Humans frequently contain per- and polyfluoroalkyl substances (PFASs), synthetic organic chemicals usually used in manufacturing. Due to their resistance to metabolism, these chemicals accumulate in the liver, kidneys, and blood after ingesting, inhaling, or coming into contact with the skin. Because of toxicity concerns, older PFAS have decreased, but newer PFAS are rising. Common PFAS have been linked to a considerable increase in the risk of cardiovascular disease, which includes heart failure, coronary heart disease, and stroke, according to studies. PFAS causes oxidative stress, endothelial dysfunction, hypercoagulability, hyperlipidemia, and platelet activation, among other pathways that lead to cardiovascular disease.
Metals:
Contaminant metals from air pollution and other sources, such as lead, zinc, cadmium, arsenic, mercury, nickel, and iron, increase the risk of cardiovascular disease. These metals cause lipid peroxidation, produce reactive oxygen species, reduce vasodilation, and interfere with lipid metabolism. Even at modest exposure levels, elevated blood concentrations of these metals are associated with an increased risk of cardiovascular disease due to their links to obesity, hypertension, hyperlipidemia, and diabetes. Exposure to heavy metals has been linked to increased risks of peripheral artery disease, coronary artery disease, and stroke.
How Can the Exposure to Environmental Pollution Be Reduced?
Reducing environmental pollution is a multifaceted strategy combining individual behavioral adjustments, regulatory actions, and public health policies to address the cardiovascular effects of environmental toxins:
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It is essential to strengthen environmental rules to lower air pollution emissions and restrict the release of poisons from industrial sources. Regular enforcement and monitoring are crucial to guarantee compliance and safeguard the public's health.
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Healthcare providers, legislators, and the general public can be encouraged to take preventative action and advocate for cleaner surroundings by learning about the cardiovascular risks of environmental contaminants.
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Nature-friendly design, encouraging active transportation, and lowering fossil fuel dependency can all help lessen air pollution exposure and enhance cardiovascular health outcomes.
Conclusion:
Environmental contaminants have a significant and diverse effect on cardiovascular health, influencing populations all over the world in a variety of ways. To limit exposure, establish regulatory frameworks, and promote sustainable practices, governments, healthcare professionals, researchers, and the general public must work together to address this issue. As great as the problem is, there is also a great chance to enhance cardiovascular health by tackling environmental contaminants.
