Air Pollution's Impact: Diseases And Health Hazards

Air pollution is a major environmental and health risk, causing millions of deaths each year. It is responsible for a wide range of diseases, including respiratory problems, heart disease, and cancer. The specific disease outcomes most strongly linked with exposure to air pollution include stroke, ischaemic heart disease, chronic obstructive pulmonary disease, lung cancer, pneumonia, and cataract (household air pollution only). In addition, air pollution has been linked to an increased risk of metabolic dysfunction-linked fatty liver disease, several gastrointestinal disorders, and kidney diseases. It is a significant cause of morbidity and premature death, with certain populations, such as children, older adults, and people of color, being more vulnerable to its adverse effects.

Cancer

Air pollution is a major cause of disease and premature death. It is the single largest environmental health risk in Europe. Fine particulate matter (PM2.5) is the air pollutant driving the most significant health problems and premature mortality.

Outdoor air pollution poses an urgent global public health challenge, as it is linked to numerous adverse health effects, including cancer. There is substantial evidence from human and animal studies, as well as mechanistic evidence, supporting a causal link between outdoor air pollution and lung cancer incidence and mortality. It is estimated that hundreds of thousands of lung cancer deaths worldwide each year are attributable to particulate matter air pollution.

The International Agency for Research on Cancer has classified air pollution, particularly PM2.5, as a leading cause of cancer. Air pollution can affect almost every organ in the body, and due to their small size, some air pollutants can penetrate the bloodstream via the lungs and circulate throughout the body, leading to systemic inflammation and carcinogenicity.

In the UK, outdoor air pollution causes roughly 1 in 10 cases of lung cancer. While smoking has a much larger impact on lung cancer risk, air pollution still plays a significant role. Tiny particles may build up in the lungs and damage the DNA in cells, altering their division and leading to cancer. Researchers are also investigating how air pollution may cause inflammation in the lungs, potentially leading to cancer.

In addition to lung cancer, air pollution has been associated with an increased risk of several other types of cancer. A study in Hong Kong found that long-term exposure to fine particulate matter was linked to higher mortality rates from breast, liver, and pancreatic cancer. Another study of over 57,000 women suggested that living near major roadways may increase the risk of breast cancer. Furthermore, occupational exposure to benzene, an industrial chemical, is associated with leukemia and non-Hodgkin's Lymphoma.

While the evidence is more limited, air pollution may also be linked to other cancers, such as bladder cancer. Additionally, air pollution could affect gut microbiota and influence the development of digestive organ cancers.

Respiratory diseases

Air pollution is a major global health concern, causing over 6.5 million deaths annually. It is the single largest environmental health risk in Europe and a leading cause of premature death and disease. Fine particulate matter (PM2.5) is the air pollutant that causes the most harm to human health. These particles are so small that they can penetrate the lung epithelium and enter the bloodstream, travelling throughout the body and causing systemic inflammation and carcinogenicity.

Particulate matter that penetrates the lungs can cause lung inflammation, exacerbating symptoms of asthma and COPD. Air pollutants can also increase susceptibility to respiratory infections. Studies have found a significant association between outpatient consultations for upper respiratory tract infections and the concentration of air pollutants such as PM10, nitrogen dioxide, ozone, and sulphur dioxide.

Children are especially vulnerable to air pollution as their bodies and immune systems are still developing, and they breathe faster, taking in more air per unit of body weight than adults. Prenatal exposure to air pollution can negatively impact lung development and respiratory health, increasing the risk of chronic respiratory diseases in adulthood.

In addition to outdoor air pollution, indoor pollution is also a major concern. Kitchen fumes, poor ventilation, and dampness leading to mould growth can all contribute to respiratory issues. Carbon monoxide, a harmful gas found indoors, can obstruct oxygen supply to the heart.

To minimise the risks of respiratory diseases caused by air pollution, individuals can take measures such as improving indoor ventilation, reducing exposure to outdoor air pollution, and advocating for stricter air pollution regulations.

Cardiovascular issues

Air pollution is a major public health issue, causing cardiovascular and pulmonary diseases worldwide. Cardiovascular disease is the leading cause of death in the United States, with one in three Americans suffering from heart or blood vessel disease. Traditional risk factors for cardiovascular disease include male sex, older age, increased blood pressure, high total cholesterol, low HDL, and smoking. However, air pollution exposure has also been identified as a contributing factor to the development and progression of cardiovascular disease.

Fine particulate matter, or PM2.5, is of particular concern when it comes to air pollution and cardiovascular health. These particles are 2.5 micrometres or smaller in diameter and can be inhaled deeply into the lungs, where they can then affect the heart and blood vessels. Sources of PM2.5 include tobacco smoke, automobile or diesel exhaust, and wood smoke. Wildfire smoke, which includes smoke from prescribed fires, also contains PM2.5 and other pollutants, posing a risk to those with pre-existing heart conditions.

Short-term exposure to air pollution, especially fine particulate matter, can increase the risk of heart attack, stroke, arrhythmias, and heart failure in susceptible individuals, such as the elderly or those with pre-existing medical conditions. Long-term exposure to air pollution is also a risk factor for cardiovascular disease and has been linked to an increased risk of death. The American Heart Association reports that someone dies from cardiovascular disease every 40 seconds in the United States.

The effects of air pollution on cardiovascular health are not limited to PM2.5. Larger particles, such as PM10, which is related to black smoke, can also have adverse effects. Ultrafine particles, or UPs, can directly enter the systemic circulation and cause health issues. Additionally, indoor air pollution, such as from smoking, can also contribute to cardiovascular risks.

Gastrointestinal disorders

Air pollution is a major environmental health hazard and the leading cause of disease and premature death in Europe. It is responsible for more than 6.5 million deaths each year globally, a number that has increased over the past two decades. Almost every organ in the body can be impacted by air pollution, and it can lead to systemic inflammation and carcinogenicity.

Several gastrointestinal disorders have been linked to air pollution. People who live in areas with high levels of air pollution are more likely to suffer from gastrointestinal issues. The specific gastrointestinal disorders that have been linked to air pollution include irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), Crohn's disease, ulcerative colitis, and peptic ulcers. The symptoms of these disorders include abdominal pain, diarrhoea, constipation, and bloating.

The mechanisms through which air pollution contributes to gastrointestinal disorders are varied. Firstly, air pollutants such as particulate matter, volatile organic compounds (VOCs), and nitrogen dioxide (NO2) can lead to inflammation in the gastrointestinal tract, disrupting its normal functioning. This chronic exposure to air pollution has been linked to an increased risk of digestive disorders. Secondly, elevated cortisol levels, often associated with stress responses triggered by air pollution, can disrupt the digestive system's normal functioning, leading to IBS and peptic ulcers. Inflammation and oxidative stress also play significant roles in pollution-induced digestive diseases.

Additionally, chemical pollutants, including industrial chemicals, pesticides, and food additives, are associated with various digestive diseases. Exposure to these chemicals through contaminated air can disrupt the gut microbiota balance, leading to IBS, food intolerances, and colorectal cancer.

Furthermore, the intestinal tract can be damaged by exposure to gaseous and particulate matter components of air pollution, leading to intestinal diseases such as appendicitis, gastroenteric disorders, and peptic ulcers.

Kidney damage

Air pollution is a major cause of premature death and disease, posing a significant threat to global health. It is responsible for more than 6.5 million deaths each year worldwide, with fine particulate matter (PM2.5) being the leading cause of air pollution-related deaths.

One of the lesser-known dangers of air pollution is its impact on kidney health. Studies have found a connection between air pollution and an increased risk of chronic kidney disease (CKD). CKD occurs when a person's kidneys become damaged or unable to effectively filter blood.

The exact mechanisms by which air pollution damages the kidneys are not yet fully understood. However, it is believed that air pollutants can enter the bloodstream through the lungs and circulate throughout the body, leading to systemic inflammation and oxidative stress, which can adversely affect the kidneys.

People with diabetes, obesity, high blood pressure, or heart disease are at an even higher risk of developing CKD due to air pollution. In addition, certain occupations that involve exposure to industrial chemicals or agricultural pollutants may also increase the likelihood of kidney damage.

Furthermore, air pollution has been linked to cognitive impairment in patients with CKD. However, studies suggest that a kidney transplant can help to reverse these cognitive effects. While the full extent of the relationship between air pollution and kidney damage is still being investigated, the existing evidence highlights the importance of reducing air pollution to mitigate its adverse health impacts.

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