Air Pollution & Human Health: Short-Term and Long-Term Effects of Deteriorating AQI

Air Pollution & Human Health: Short-Term and Long-Term Effects of Deteriorating AQI

Air pollution has emerged as one of the most serious public health challenges worldwide. Increasing industrialisation, vehicle emissions, construction activities, fossil fuel burning, and climate-related changes have caused a steady decline in air quality. The Air Quality Index (AQI) is a standardised tool used to measure and communicate how polluted the air is and how it affects human health.

As AQI levels rise, health risks increase for everyone—not only for people with existing illnesses, but also for healthy individuals. The impact of polluted air is often invisible, gradual, and cumulative, making it particularly dangerous.

 Understanding AQI and Air Pollutants

 What is AQI?

The Air Quality Index is a numerical scale that reflects the concentration of major air pollutants in the atmosphere. It categorises air quality into levels such as good, moderate, poor, and severe, each indicating increasing health risk.

 Major Pollutants Affecting AQI

The most harmful pollutants included in AQI measurement are:

• PM2.5 (Fine Particulate Matter) – Tiny particles that penetrate deep into the lungs and bloodstream

• PM10 (Coarse Particulate Matter) – Dust and particles that affect airways

• Nitrogen Dioxide (NO₂) – Emitted from vehicles and power plants

• Sulfur Dioxide (SO₂) – Released from fossil fuel combustion

• Carbon Monoxide (CO) – Reduces oxygen delivery in the body

• Ground-level Ozone (O₃) – Triggers breathing problems

Among these, PM2.5 is the most dangerous due to its ability to enter vital organs.

 Short-Term Health Effects of Poor AQI

Short-term exposure refers to breathing polluted air for a few hours or days. Even brief exposure can trigger noticeable health problems.

 Eye, Nose, and Throat Irritation

Common early symptoms include:

• Burning or itching eyes

• Watery eyes

• Sore throat

• Nasal congestion

• Frequent sneezing

These symptoms often worsen during high-AQI days.

 Respiratory Symptoms

Polluted air directly irritates the respiratory system, leading to:

• Persistent coughing

• Wheezing

• Shortness of breath

• Chest tightness

• Reduced lung performance

People with asthma and allergies experience sudden flare-ups, often requiring medication or medical attention.

 Cardiovascular Stress

Short-term exposure also affects the heart and blood vessels:

• Increased blood pressure

• Irregular heartbeat

• Reduced oxygen circulation

• Higher risk of heart attacks during severe AQI episodes

Studies show hospital admissions rise sharply during pollution spikes.

 Effects on Children

Children react faster to pollution due to developing lungs:

• Frequent respiratory infections

• Reduced physical activity tolerance

• Eye and throat irritation

• Increased school absenteeism

 Long-Term Impact on Respiratory Health

Long-term exposure means breathing polluted air over months or years. The damage caused is often permanent.

 Chronic Lung Diseases

Prolonged pollution exposure increases the risk of:

• Asthma development

• Chronic bronchitis

• Chronic Obstructive Pulmonary Disease (COPD)

• Persistent airway inflammation

Lung function gradually declines, affecting daily activities.

 Lung Cancer Risk

Air pollution is a major non-smoking-related cause of lung cancer:

• Fine particles damage lung cells

• DNA mutations increase over time

• Cancer risk rises even in non-smokers

 Impact on Children’s Lung Development

Children exposed to polluted air for years may experience:

• Stunted lung growth

• Lower lung capacity in adulthood

• Higher lifetime risk of respiratory disease

 Cardiovascular Damage from Prolonged AQI Exposure

Once pollutants enter the bloodstream, they affect the heart and blood vessels directly.

 Blood Vessel Inflammation

Long-term exposure leads to:

• Chronic inflammation of arteries

• Narrowing of blood vessels

• Increased plaque formation

 Heart Disease and Stroke

Consistent exposure increases the risk of:

• Hypertension

• Heart attacks

• Stroke

• Heart failure

Even individuals with no prior heart disease may develop cardiovascular problems over time.

 Effects on Brain and Mental Health

Air pollution is increasingly linked to neurological and psychological disorders.

 Cognitive and Neurological Effects

Pollutants crossing the blood–brain barrier can cause:

• Brain inflammation

• Memory impairment

• Reduced concentration

• Faster cognitive decline

Long-term exposure increases the risk of neurodegenerative diseases.

 Mental Health Disorders

Research associates polluted air with:

• Anxiety

• Depression

• Mood instability

• Increased stress levels

Chronic inflammation and reduced oxygen supply may alter brain chemistry.

 Impact on Children’s Brain Development

Children exposed to high AQI levels may experience:

• Reduced attention span

• Learning difficulties

• Lower academic performance

 Immune System Suppression

Air pollution weakens the immune system, making the body more vulnerable to illness.

 Increased Infections

Common effects include:

• Frequent colds and flu

• Prolonged recovery time

• Severe respiratory infections

 Chronic Inflammation

Long-term exposure causes continuous immune activation, leading to:

• Reduced immune efficiency

• Higher risk of autoimmune disorders

• Poor response to infections

 Effects on Pregnancy and Child Health

Pregnant women and unborn babies are especially vulnerable.

 Pregnancy Complications

High AQI exposure increases the risk of:

• Preterm birth

• Low birth weight

• Miscarriage

• Developmental abnormalities

 Long-Term Impact on Children

Children exposed before birth may face:

• Weak lung development

• Increased asthma risk

• Reduced immunity

 Skin Damage and Premature Aging

The skin absorbs pollutants directly from the air.

 Skin Problems Caused by Pollution

Long-term exposure leads to:

• Dull and uneven skin tone

• Acne and clogged pores

• Eczema flare-ups

• Hyperpigmentation

 Accelerated Aging

Pollution generates free radicals that:

• Break down collagen

• Cause early wrinkles

• Reduce skin elasticity

Skin damage often reflects deeper internal inflammation.

 Reduced Life Expectancy and Mortality Risk

One of the most severe consequences of long-term air pollution exposure is early death.

 Increased Mortality Rates

Polluted air increases deaths due to:

• Heart disease

• Stroke

• Lung cancer

• Chronic respiratory illness

 Shortened Lifespan

Studies estimate that continuous exposure to high AQI levels can reduce life expectancy by several years.

 Why AQI Awareness and Prevention Are Critical

Air pollution damage accumulates silently over time. Preventive action is essential.

 Individual Preventive Measures

• Monitor daily AQI levels

• Avoid outdoor activity during severe AQI

• Improve indoor air quality

• Use protective measures when exposure is unavoidable

 Community and Policy Importance

• Strong pollution-control policies

• Sustainable transport and energy use

• Public awareness and participation

Conclusion

Air pollution is not just an environmental concern—it is a direct threat to human health. Poor AQI affects nearly every organ system, causing both immediate discomfort and long-term, life-threatening diseases. From respiratory and cardiovascular damage to cognitive decline and reduced lifespan, the effects of polluted air are profound and far-reaching.

Understanding AQI and its health consequences empowers individuals and communities to take preventive action. Protecting air quality is ultimately about safeguarding human health today and ensuring a healthier future for generations to come.