THERE are some countries in the world where the air is so polluted you can forget about coming home with a healthy holiday glow.

The World Health Organization (WHO) released its 2014 report into global air pollution with some concerning finds.

The database looked at the air pollution levels of 1600 cities across 19 countries by using a reading called PM2.5 and PM10. PM2.5 is considered the best indicator of assessing health impacts from air pollution and examines the concentration of fine particulate pollution of 2.5 micrometers or less in diameter.

The particles might be smoke, dirt, mould or pollen and their fine size poses the biggest risks to human health as they can be inhaled and accumulated in the respiratory system. WHO says there is no safe level of PM2.5.

Here are the 10 most polluted countries in the world.

1. Pakistan

Average PM2.5 pollution: 101 ug/m3

With a population of almost 180 million urban air pollution in Pakistan causes thousands of adult deaths each year.

A World Bank report found that outdoor air pollution alone causes more than 80,000 hospital admissions per year; nearly 8,000 cases of chronic bronchitis, and almost five million cases of lower respiratory cases in children under the age of five.

2. Qatar

Average PM2.5 pollution: 92 ug/m3

With a population of 2 million people and growing, Qatar also faces increased pollution from its high rate of construction and busy air traffic making it the second most polluted country in the world.

3. Afghanistan

Average PM2.5 pollution: 84 ug/m3

The Afghanistan government estimates that air pollution is responsible for 3000 deaths every year in the capital Kabul.

With a population of almost 30 million, Afghanistan suffers from traffic congestion, dust and the geographical limitations of a mountainous city.

The city’s swelling size has led to illegal homes powered by diesel generators or for those who can’t afford electricity, they burn tires and plastic bags for fuel.

4. Bangladesh

Average PM2.5 pollution: 79 ug/m3

Home to nearly 155 million people, the air quality has fallen nearly 60 per cent in the last 10 years. In fact three Bangladeshi cities are in the top 25 cities with the poorest air quality.

5. Iran

Average PM2.5 pollution: 76 ug/m3

With a population of more than 76 million, four cities in Iran make the top 10 list of most polluted cities in the world. A combination of poor political decisions, substandard gasoline and traffic congestion means that its residents inhale a deadly mix of rubber particles, asbestos, sulfur dioxide, nitrogen oxide and carbon monoxide.

6. Egypt

Average PM2.5 pollution: 74 ug/m3

The average resident of Cairo breathes in more than 20 times the acceptable level of air pollution every day according to WHO. The growing number of cars, factories and power plants, and the use of old heating methods such as burning coal and wood are considered to be the main man-made sources of air pollution.

7. Mongolia

Average PM2.5 pollution: 64 ug/m3

It’s population may only be 2.7 million but Mongolia’s long, cold winters that can drop to minus 40 degrees Celsius means that many Mongolians burn coal for cooking and heating creating a huge air pollution problem. Its capital Ulaanbaatar is one of the most polluted cities in the world.

8. United Arab Emirates

Average PM2.5 pollution: 61 ug/m3

It may be one of the richest regions in the world, but it has made its fortune from the oil and gas industries that are notoriously filthy. With a population of more than 9 million, Dubai launched an annual “car free day” in 2010 to try and tackle its problems with congestion and pollution.

9. India

Average PM2.5 pollution: 59 ug/m3

In the winter of 2013, air pollution in New Delhi was 60 times higher than the level considered safe according to India’s Center for Science and Environment (CSE) and it had the highest rate of air pollution in the world according to WHO.

Pollution from construction sites, industrial emissions, open fires, vehicle emissions and a staggering population of 1.2 billion put India at number nine on the list.

10. Bahrain

Average PM2.5 pollution: 57 ug/m3

Air pollution is not entirely relegated to the world’s developing nations. The high income country of Bahrain may only have a population of 1.3 million but it scraped in at number 10 on the list due to its high levels of pollution from energy production, dust, smoke and industrial emissions.