Which pollutant is commonly monitored for its effects on human health in urban areas?

Particulate matter is a critical pollutant monitored in urban areas because it poses significant health risks due to its ability to penetrate deep into the respiratory system. Particulate matter, often categorized into PM10 and PM2.5 based on the size of the particles, can include a variety of substances such as dust, soot, and aerosols. These tiny particles can be inhaled, leading to adverse health effects, including respiratory and cardiovascular diseases.

Moreover, urban areas tend to have higher concentrations of particulate matter due to activities such as vehicle emissions, industrial processes, and construction. Public health studies have demonstrated a clear link between elevated levels of particulate matter and increased rates of asthma, lung cancer, heart attacks, and other serious health conditions. Therefore, monitoring particulate matter is essential for both understanding air quality and implementing measures to protect public health.

In contrast, while carbon dioxide is an important greenhouse gas, its direct effects on human health in urban settings are less significant compared to particulate matter. Nitrogen dioxide also contributes to respiratory problems but is typically not as routinely monitored due to its less severe health impacts compared to particulate matter. Hydrogen sulfide is a toxic gas that can have health effects, but it is less commonly present in typical urban settings compared