Recently David Boyd , the UN Special Rapporteur on Human Rights and the Environment , released a fact that caused quite a stir. Worldwide, air pollution is responsible for the premature death of 7 million people a year , 800 every hour. 

These figures show us, once again, that smog damages our health in a very significant way. However, it can happen that we feel powerless : if we live in a big, chaotic and busy city, how can we defend ourselves? 

We asked for the opinion of Dr. Paolo Contiero , Head of the Simple Structure of Environmental Epidemiology of the Cancer Institute of Milan . Dr. Contiero did not limit himself to explaining and commenting on the data  but he also offered us some simple advice that we can put into practice immediately.

7 million deaths from premature death a year: how many are due to cancer?

The global order of magnitude of the impact of pollution is roughly that indicated by Boyd of the United Nations, indeed, it could be even greater . 

According to a recent German study , in Europe every year there are more or less 800 thousand more deaths , compared to those that would occur if the level of smog were lower. Of these 800 thousand, 7% (therefore 50-55 thousand people per year ) is mainly due to lung cancer . 

All these studies take into account only the environmental risk factors that are established and almost only count lung cancers. But the situation is very complex: there are many other cancers that are affected, in one way or another, by pollutants. 

Other analyzes suggest that pollutants influence not only the onset of the disease, but also its progression .

My group at the Cancer Institute has studied the survival of women who have been diagnosed with breast cancer : it has been seen that, with high levels of atmospheric disease, the prognosis worsens by about 60%. Two other American studies go in the same direction.

All these evidences are not yet included in the estimates I mentioned earlier, which are very reliable but refer only to absolutely certain and sure factors. I expect that in the coming years, with advances in scientific research and the definition of as yet unknown risk factors, these numbers may increase further . 

What are the main sources of pollution?

Pollution can be divided into two broad categories: indoor , that is the air we breathe inside the house, and outdoor , that is the smog we breathe outdoors.

In the world, the outdoor component is relevant practically everywhere . The indoor one also exists in Europe, but has an even greater weight in Africa, Asia and South America , where backward methods of cooking food are still used.

How do you demonstrate a cause-and-effect relationship between pollution and cancer?

The IARC , the international agency for field research, expressed its opinion on the relationship between atmospheric particulate matter and lung cancer .

What does the IARC do? For all the most relevant risk factors, it collects all the published studies and brings together the best experts in the world , who issue a final verdict. It is a process that can take years. 

This final verdict has several levels of evidence. On the relationship between atmospheric particulate matter and lung cancer , level 1 is reached , the highest ever. In short, it is reliable scientific evidence beyond any margin of doubt . 

As for the effects on  other types of cancer , such as breast cancer, the situation is more uncertain .

For prevention we can play sports, eat better, but we cannot change the air we breathe. How do we protect ourselves?

First of all, each of us has the opportunity to elect the political class . When we go to vote, we encourage our politicians to improve the transport plan , which is the central issue if we want to have cleaner air.

We should teach children , from an early age, to use public transport more . If we drive them to kindergarten every day by car, and we always pick them up by car, we are not setting a good example.

Turning to individual caution choices, one of the most important protective factors is sporting activity , which helps us prevent obesity, speed up metabolism and protect our health.

One caveat, though. I know that for those who live in the city it is not easy, but we must keep away from polluting sources when we play sports . If we go running or biking, we avoid busy roads, especially at peak times.

As for indoor pollution, what can we do?

To improve the air we breathe indoors, we can follow three recommendations .

Let’s start with the first: we ventilate our homes several times a day , obviously avoiding the moments when the smog outside is particularly high.

If we use a grill for cooking (which in any case is not the best choice), it is advisable to equip ourselves with an efficient hood , which avoids the spread of dangerous fumes in the rooms.

The third recommendation is the result of some studies carried out in schools, from which it was found that some low-quality furniture was built using formaldehyde , a pollutant that can become dangerous. When we choose the furniture, therefore, we pay attention and verify that they have a certification . 

Do children need some extra caution?

Children ( as well as pets) are closer to the ground . If we are walking with a very small child on a busy street, it can be useful to hold him in our arms to limit his exposure to atmospheric particulate matter.

More and more studies are linking children’s health (including their cognitive and psychological development) to the presence of green areas . If your child plays frequently in parks, even his school performance can improve!

I would add that the CDC research institute in Atlanta advises children to do outdoor sports only if the level of smog is not excessive. Another British study shows that even athletes perform worse if they train in heavily polluted areas. 

A last tip for our readers?

We have many weapons to defend our health and live better. Cities like Milan (and beyond), for example, make a bike sharing service available to everyone : it is a simple daily habit that brings great results. 

In fact, if we use the bike we do a favor to ourselves , but also to the health of our children, our loved ones and the environment.