PM2.5 stands for particulate matter 2.5 microns or smaller. These particles are 30 times thinner than a human hair and come from car exhaust, power plants, wildfires, and burning fuel. They are small enough to bypass your body's natural defenses and enter your bloodstream.

How does air pollution affect the body?

Air pollution affects virtually every organ in the body. PM2.5 particles enter your lungs, pass into your bloodstream, and travel to your heart, brain, kidneys, liver, and other organs. This causes chronic inflammation, increasing risks of heart disease, stroke, lung cancer, dementia, and many other conditions.

How many people are affected by air pollution?

99% of the global population breathes air that exceeds WHO safety guidelines. Air pollution kills approximately 8 million people every year—more than AIDS, malaria, and tuberculosis combined.

Saint Helena, Ascension and Tris's Saint Helena Air Pollution Report

Overview

Air Pollution in Saint Helena

Saint Helena faces significant air pollution challenges. 0% of districts exceed the WHO guideline for clean air. This is putting 6 thousand across 8 districts at risk.

The average PM2.5 over 2023 was 1.7µg/m³. That's 0.3 times the WHO guideline for clean air of 5µg/m³.

This is equivalent of everybody, including children, smoking about 28 cigarettes in a year.

Trends

Air Quality Trend

Annual PM2.5 levels from 2014 to 2023. The WHO guideline for safe air is 5 µg/m³.

Health Impact

Life Expectancy Impact

If Saint Helena met the WHO guideline of 5 µg/m³, the average person would live 0 years longer.

That's 0 years of life stolen from 6 thousand people. Years of watching children grow up. Years of building a career. Years of quiet mornings and celebrations.

Lives cut short. Breathing kills.

Most Polluted

Districts with Highest Pollution

The top 8 most polluted districts in Saint Helena. These areas face the greatest health burden from air pollution.

1.St. Paul's
0 years lost
2.Blue Hill
0 years lost
3.Half Tree Hollow
0 years lost
4.Jamestown
0 years lost
5.Alarm Forest
0 years lost
6.Longwood
0 years lost
7.Levelwood
0 years lost
8.Sandy Bay
0 years lost

Exposure

Population Exposure by Pollution Level

Distribution of population across different PM2.5 pollution levels. The WHO guideline is 5 µg/m³—only populations below this threshold are breathing safe air.

< 5 µg/m³

100%

5-10 µg/m³

10-15 µg/m³

15-25 µg/m³

25-35 µg/m³

> 35 µg/m³

Districts

All 8 Districts in Saint Helena

Complete air quality data for every district in Saint Helena, sorted by population.

District	Population	PM2.5 µg/m³
Longwood	1K	1.7
St. Paul's	1K	1.7
Half Tree Hollow	971	1.7
Jamestown	603	1.7
Levelwood	516	1.7
Blue Hill	493	1.7
Alarm Forest	410	1.7
Sandy Bay	278	1.7

Showing 8 districts, sorted by population (largest first). PM2.5 values are for 2023. Years lost calculated against WHO guideline of 5 µg/m³.

Breathing in Saint Helena is Injurious to Health.