Pollution's Impact: Diseases Caused And Ways To Prevent Them

Pollution is a pressing global issue with far-reaching consequences for human health and the environment. It is a major cause of disease and premature death, with air pollution being the most significant contributor. Air pollution is caused by various factors, including industrialization, combustion, and inadequate waste management, leading to increased levels of harmful pollutants in the atmosphere. These pollutants, such as fine particulate matter (PM2.5), nitrogen dioxide (NO2), and ozone (O3), can have detrimental effects on human health, causing respiratory and cardiovascular diseases, cancer, and even contributing to premature mortality. The impact of pollution is particularly severe in low- and middle-income countries, where exposure to pollutants is higher due to factors such as the combustion of low-quality fuels and inadequate waste management practices. With pollution causing approximately 9 million deaths per year, it is essential to address its root causes and implement effective pollution-control policies to mitigate its devastating impact on human health.

Air pollution and cancer

Air pollution is a significant and far-reaching threat to public health, with 99% of the world's population breathing unhealthy air, according to the World Health Organization (WHO). It is a major contributor to the global disease burden, with emissions from major sources such as industry, power generation, transportation, and domestic burning exceeding WHO health-based air quality guidelines. Outdoor air pollution, in particular, poses a pressing global health challenge due to its ubiquity and severe adverse health effects, including cancer.

Numerous studies have established a link between air pollution and lung cancer. Outdoor air pollution is estimated to cause approximately one in ten cases of lung cancer in the UK, and it is responsible for hundreds of thousands of lung cancer deaths worldwide each year. While smoking is a more significant risk factor for lung cancer than air pollution, it is important to note that air pollution can also increase the risk of lung cancer in non-smokers. Nearly half of lung cancer cases in people who have never smoked are associated with air pollution.

The mechanisms by which air pollution contributes to lung cancer are still being investigated. One theory suggests that tiny particles from air pollution may build up in the lungs and damage the DNA in cells, altering their division and leading to cancer. Additionally, air pollution may cause inflammation in the lungs, which could be another pathway to cancer development.

Recent studies have also found an association between air pollution and an increased risk of other types of cancer, including breast cancer. Research has shown an 8% increase in breast cancer incidence in areas with higher exposure to fine particulate matter (PM2.5). This association is particularly relevant given that air pollution is a pervasive exposure, impacting almost everyone. Additionally, a 2024 meta-analysis of 61 studies found a significant relationship between exposure to air pollutants and cancer incidence and mortality, with lung cancer being the most frequently studied cancer.

While pollution is a risk factor for cancer, it is essential to consider other lifestyle risk factors that can be modified to reduce cancer risk. These include diet, exercise, sun exposure, and alcohol consumption. Additionally, reducing air pollution not only mitigates the risk of lung cancer but also provides a range of health benefits, such as improved diet and increased physical activity, which can contribute to lower rates of other cancers.

Pollution and cardiovascular disease

Air pollution is a well-known risk factor for chronic non-communicable diseases, and it has been estimated that it contributes more to global morbidity and mortality than all other known environmental risk factors combined. Fine particulate matter (PM2.5) and ozone gas have been the primary focus of environmental health research and regulatory standards due to their detrimental health effects.

The Global Burden of Disease (GBD) study estimates that pollution caused approximately 9 million deaths worldwide in 2019, with 61.9% attributed to cardiovascular disease, including ischemic heart disease and stroke. This indicates that pollution plays a significant role in the development of cardiovascular disease, and its impact may be greater than previously recognized.

The adverse health effects of air pollution exposure are well-documented, particularly in relation to cardiovascular and respiratory diseases. Short- and long-term exposure to ambient air pollution (AAP) and outdoor particulate matter (PM) have been linked to an increased risk of cardiovascular events and mortality. Fine particulate matter (PM2.5) and ultrafine particles can penetrate deep into the lungs and enter the bloodstream, impacting the cardiovascular system. The size of inhalable particles also plays a role, with smaller particles (_100 nm) associated with more severe adverse effects following short-term exposure.

Additionally, air pollution has been found to contribute to the development and exacerbation of cardiovascular disease. Evidence suggests that exposure to increased concentrations of PM2.5 over a short period can trigger cardiovascular disease-related heart attacks and death. Long-term exposure to air pollution accelerates the process of atherosclerosis, leading to a higher risk of cardiovascular events such as heart attacks and strokes.

The impact of air pollution on cardiovascular health is a growing concern, and it is essential to raise awareness among the public, the scientific community, and policymakers. Incorporating pollution reduction strategies into cardiovascular disease prevention programs could potentially save millions of lives. This includes individual measures such as the use of face masks and in-home air purifiers, as well as societal-scale interventions to control pollution at its source and transition to clean energy.

Pollution and neurological disorders

Air pollution is a serious and common public health concern associated with growing morbidity and mortality worldwide. It is a global public health issue, with the Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study reporting that air pollution alone caused 6.7 million deaths globally in 2016. This number is expected to double by 2050 if no action is taken.

Neurological disorders represent the largest cause of disability-adjusted life-years and the second-largest cause of global deaths, after cardiovascular diseases. A 2017 report by The Lancet Commission on pollution and health highlighted that all types of pollution (air, water, soil, chemical, and occupational pollutants) are the world's largest environmental cause of poor health, responsible for about 9 million deaths in 2015, which is 16% of all deaths globally.

Several studies have found a significant link between air pollution and neurological disorders, with particulate matter air pollution associated with impaired cognitive function, accelerated cognitive decline, Parkinson's disease, Alzheimer's disease, and dementia. A 2020 study by researchers at Harvard University, which analysed 17 years' worth of hospital admissions data from over 63 million older U.S. adults, found that for each 5 micrograms per cubic meter of air (μg/m3) increase in annual PM2.5 concentrations, there was a 13% increased risk of first-time hospital admissions for Parkinson's disease and Alzheimer's disease and related dementias. This risk remained elevated even below supposedly safe levels of PM2.5 exposure.

Another study, which used genetically modified mice, showed that air pollution can produce neuropathological damage in individuals susceptible to oxidative stress. Further, human studies have shown that short- or long-term exposure to air pollution in the elderly can cause hypomethylation in peripheral lymphocytes, and higher exposure to traffic-related air pollution is associated with shorter leukocyte telomeres, a sign of biological ageing.

Given the adverse effects of air pollution on neurological health, there is a need for stricter standards and policies to reduce PM2.5 concentrations and improve overall air quality.

Pollution and respiratory disease

Air pollution is a pressing global issue that poses significant risks to human health, with vulnerable populations identified across the world. The respiratory system is remarkably resilient to air pollution, but constant exposure to high levels of particle pollution can contribute to reduced respiratory function.

Particle pollution exposure has been linked to a range of respiratory health effects. These include respiratory symptoms such as coughing, phlegm, and wheezing, as well as more severe outcomes like acute respiratory infections, respiratory hospitalizations, and premature mortality in people with chronic lung disease. Long-term exposure to fine particles can also lead to a decrease in lung function growth in children and an increased risk of asthma development.

The aging process naturally weakens the lungs, making older adults more susceptible to the harmful effects of air pollution. The gradual decline in lung function, coupled with a weaker immune system, puts older individuals at greater risk of respiratory infections and other serious illnesses. Additionally, older adults are more likely to have pre-existing chronic illnesses, which can be exacerbated by exposure to air pollutants.

Children are also at increased risk due to their smaller, developing airways and higher breathing rates relative to their size. Their still-developing immune systems make them more susceptible to respiratory infections, and spending more time outdoors can increase their exposure to air pollution.

Pregnant individuals are another vulnerable group, as physical changes during pregnancy already put stress on the body. Exposure to air pollution during pregnancy can increase the risk of hypertensive disorders, intrauterine inflammation, and damage to the placenta, which can negatively affect fetal growth and development.

Climate change and air pollution are closely linked, with climate change amplifying air pollution levels. This combination poses a significant threat to respiratory health, and there is an urgent need for interventions to tackle these complex challenges.

Pollution and diabetes

Air pollution and diabetes are responsible for millions of deaths globally each year. A study by researchers at Washington University School of Medicine in St. Louis, Missouri, found a strong link between air pollution and diabetes. The study, which was published in The Lancet Planetary Health, revealed that air pollution contributed to approximately 3.2 million cases of diabetes and 8.2 million years of healthy life lost globally in 2016.

Diabetes is a metabolic disorder caused by insufficient insulin secretion and impaired biological effects, resulting from a combination of genetic and environmental factors. Type 2 diabetes, in particular, is a chronic disease characterized by high blood sugar levels due to problems with insulin production and utilization. It often develops gradually and is influenced by lifestyle factors such as diet, exercise habits, age, and genetics.

Air pollution has been identified as a significant environmental problem, especially in developing nations. Fine particulate matter (PM2.5) and other air pollutants like PM10 and NO2 are associated with an increased risk of developing type 2 diabetes. The risk of pollution-induced diabetes is higher in lower-income countries with less stringent clean air policies, such as India, China, and Indonesia. Even at levels deemed "safe" by organizations like the EPA and WHO, the risk remains significant.

The exact mechanism linking air pollution and diabetes is still not fully understood, but it is believed that air pollutants induce diabetes through increased inflammation, oxidative stress, and endoplasmic reticulum stress. Additionally, air pollution is a known driver of cardiovascular disease, which is a common complication of diabetes. The onset and progression of diabetes can be influenced by exposure to air pollutants, leading to adverse health outcomes.

To address the issues of air pollution and diabetes, interventions such as portable air cleaners, increased physical activity, and policies promoting cleaner air and healthier lifestyles are essential. These interventions can help reduce the impact of air pollution on people with diabetes and potentially prevent the development of the disease.

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