The dirtiest country in the world is Pakistan. The air in the country is polluted. The main cause of this pollution is smoking, smoke emission from cars and industries. Many other countries like Egypt, India, UAE, Iran, Mongolia, Afghanistan and Qatar has be marked by World Health Organization (WHO) as unhealthy countries for living. These countries do not pay attention to their air dirtiness.
In terms of human initiated dirt, African countries are known to be dirty; you would see children picking food from a heap of waste. That’s why certain diseases are prevalent in Africa. Bulgaria is also known to be dirty.