Out of eight people who die one of which is the result of air pollution said the agency and is now the single largest environmental health danger.
According to Frank Kelly, who is a director at King's College London, pollution is something very hard to avoid as we all have to breathe.
Tiny particles are able to get deep into the lungs and cause irritation which is the primary risk. Scientists also believe, it is one of the main culprits for inflammation in the heart, which leads to chronic problems or heart attacks.
4.3 million people died from indoor air pollution out of which mostly were from Asia as a result of using wood and coal stoves as according to WHO. In contrast to 3.7 million deaths from out door pollution in the year 2012 and nearly 90% was from those countries which are still developing.
Since many people are exposed to both indoor as well as outdoor pollution and their deaths can be an attribute of both areas, the agency has reduced the numbers from 8 million to 7 million. Anywhere the figures are double the previous figures and is based on modelling.
The reason for the increase in numbers is due to the fact that now the agency is better informed about the health effects of pollution with its improved detection systems. It was only last year that the cancer agency of WHO made air pollution as carcinogen. Linking dirty air to lungs and bladder cancer.
Women were more vulnerable than men to air pollution in developing countries as they are more indoors and breathing the polluted air and soot from the fire places according to Flavia Bustreo, the Director-General for family, women and children's health.
More research is need according to other experts to make out which was the most deadliest component of pollution so that measures can be put in place to control it.
Majid Ezzati says that they don't know as yet if dust from the Sahara is as bad diesel fuel or burning coal or vice verse.
As according to Kelly, it is mostly up to governments to erode away at pollution levels by legislations, removing power stations from cities and providing cheap alternatives for indoor wood and coal stoves.
He also goes on to say that one can reduce his exposure to pollution by not travelling during rush hours or taking smaller roads. There is no evidence that face masks work in heavily polluted cities and more over, mask send the wrong message out, that you pollute and we are able to protect ourselves with masks.