What significant health risks increase for individuals in polluted cities?

Individuals living in polluted cities face significant health risks primarily because air pollution introduces harmful particulate matter, toxic chemicals, and other pollutants into the atmosphere, which can be inhaled. This exposure has been scientifically linked to various serious health conditions, particularly affecting the cardiovascular and respiratory systems.

Heart attacks can occur as a result of increased inflammation and oxidative stress caused by these pollutants, which can lead to the hardening of arteries and create a higher risk for cardiovascular events. Respiratory diseases, including chronic obstructive pulmonary disease (COPD) and asthma, are exacerbated by air pollutants that irritate the airways and lung tissue. Additionally, long-term exposure to air pollution is a well-established risk factor for lung cancer, as certain carcinogenic substances can lead to mutations in lung cells.

The other choices include health issues that are not strongly associated with air pollution, such as digestive issues and skin allergies, which while they can be problematic, do not have the same direct evidence linking them to air quality as heart attacks, respiratory diseases, and lung cancer do. Therefore, the most significant health risks associated with living in polluted cities focus on cardiovascular and respiratory conditions.