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Chapter Three Impacts of Global Climate Change

persistent inflammatory responses in the lungs, damaging the normal structure of airways
and alveoli, ultimately resulting in airflow limitation and breathing difficulties. For patients
already diagnosed with COPD, air pollution may exacerbate symptoms and increase the need
for hospitalization.
3.Asthma
Airborne particulate pollution can trigger or exacerbate asthma symptoms, leading to
frequent attacks. For people already suffering from asthma, environmental pollutants may
reduce their response to conventional treatments, making the condition more difficult to
control. Studies show that high concentrations of PM2.5 and PM10 can cause airway con-
striction and inflammatory responses, increase airway resistance, and worsen symptoms such
as breathing difficulties, coughing, and wheezing in asthma patients. Particularly in children,
long-term exposure to polluted air may impair lung function development, increasing the
risk of developing asthma in the future.
4.Lung Cancer
Studies have shown significant associations between long-term exposure to high con-
centrations of particulate pollution and lung cancer incidence. Certain types of fine particu-
late matter contain carcinogens that can directly damage DNA and promote cancer cell for-
mation and development. The World Health Organization (WHO) has classified outdoor air
pollution as a Group 1 carcinogen, highlighting its severe threat to human health. Long-term
inhalation of fine particulate matter containing heavy metals, polycyclic aromatic hydrocar-
bons (PAHs), and other harmful chemicals increases the risk of lung cancer, particularly in
urban areas and regions with concentrated industrial emissions.
(II) Health Risks of Long-Term Exposure to Pollutants
In addition to respiratory diseases, long-term exposure to particulate pollution may also
trigger other serious health issues.
1.Cardiovascular Diseases
Fine particulate matter can enter the bloodstream and reach the heart and other organs,
causing vasoconstriction, elevated blood pressure, and arrhythmias. Long-term exposure
increases the risk of heart attacks, strokes, and heart failure. Studies have shown that air pol-
lution is closely linked to the occurrence of cardiovascular events. Particularly among the
elderly and patients with pre-existing cardiovascular conditions, inhalation of fine particulate
matter may accelerate arterial hardening, increase the risk of thrombosis, and trigger fatal
cardiovascular events.
2.Impact on the Nervous System
Some studies have found that long-term exposure to high concentrations of particulate
pollution is associated with cognitive decline and the occurrence of neurodegenerative dis-
eases such as Alzheimer’s disease. This may be due to pollutants crossing the blood-brain
barrier into the brain, affecting normal neuronal functions. Long-term exposure to fine par-
ticulate matter may trigger chronic inflammatory responses, damage nerve cells, and affect

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