Czech scientists: health effects of air pollution in humans can show after decades
Pioneering research by Czech scientists suggests that the quality of the air we breathe may affect our health for decades to come. In the early 1980s the most serious pollutant in this country was sulphur dioxide, produced mainly by coal-fired power plants and households using coal for heating.
Research has proved that the air we breathe in cities is filled with fine dust particles which carry harmful chemical substances from car fumes.
"According to our research we believe that one of the worst are carcinogenic polycyclic aromatic hydrocarbons (PAHs). When we analysed extracts from the particles which were collected during summer and winter in two different places in Prague, as well as Teplice in North Bohemia and Prachatice in South Bohemia, it seems that carcinogenic PAHs are responsible for roughly 50 percent of biological activity which is inducing genetic damage, which means injury on the level of DNA."
Czech scientist Dr Radim Sram from the Institute of Experimental Medicine of the Czech Academy of Sciences and his team have been monitoring the concentration of PAHs for more than ten years.
"I am afraid that the importance of those carcinogenic PAHs is not fully recognised yet because these measurements are not properly done in many countries. In fact, we have been measuring those fine particles as well as the concentration of PAHs on a daily basis already since 1993. This was possible due to our collaboration with the United States Environment Protection Agency. When we recognised that there is another problem in Prague, we started measuring on a daily basis in 2000. So when you compare this knowledge with what is accessible in other European countries, I think that you have no similar data in other European countries, or only in a few of them."
The most recent study, co-financed by the European Union, compared two groups of people: Policemen who spend their working days out in the streets and people who work indoors.
They carried special tubes which monitored the air they breathed. It turned out that people who work in the polluted streets of cities breathe in twice the amount of the harmful substances than those working indoors. In blood samples provided by the policemen, Dr Sram's team found alterations in the genetic code, which could potentially cause cancer.
Apart from those working outside in the cities, another group of the population is especially vulnerable to the exposure to city air.
"We are afraid that most vulnerable to the exposure to those PAHs are probably children in the period of pregnancy. This exposure is responsible also for the decrease of birth weight, also inducing some mutations. From the point of intrauterine growth retardation what seems to be the most interesting is that this type of functional deficiency affects such a child not only in the period of childhood but such a person is affected during their whole life. These people run an increased risk of non-insulin-dependent diabetes, hypertension and atherosclerosis."
And as Dr Sram adds, at the age of fifty you certainly cannot remember which chemicals your mother was exposed to during her pregnancy.
However pessimistic the results of the studies may sound, not all city dwellers are facing the same risk. Dr Radim Sram.
"Genetic damage in some people who have special genetic makeup can be worse that in other people who are able to metabolise such chemicals properly. Certainly what you can do for yourself is your lifestyle. I'm not talking about smoking which is quite clear but also it is a question of healthy diet."
