Nobody likes breathing lungfulls of pollution from big cities. Least of all the citizens of Mexico City, whose air is so contaminated it is a serious health hazard. Now the IAEA, through its Technical Cooperation programme, is helping Mexicans breathe a little easier. The Agency has teamed up with local scientists and regulatory authorities on a project aimed at making the air in the capital safer for its people.
For the past two years nuclear "knowhow" has been used to analyse air samples collected from across the city. These nuclear techniques give important new data about the size, type and level of contaminants in dust particles suspended in the air. Armed with this knowledge, scientists and health care experts can better understand and tackle the health dangers associated with pollution, like cancer and respiratory disease. Air pollution in Mexico City contributes to around 12,000 deaths per year, with trends showing children and the elderly increasingly treated for respiratory disease. Exhaust fumes from the city´s four million motor vehicles are a main source of contamination.
Unlike traditional methods for analysing air samples, nuclear tools are sensitive enough to extract key information about contaminants in small, fine particles. The smaller a toxic particle the more damaging to human health, because it can penetrate deeply into the lungs. It is hoped that better information about release rates of elements like sulphur, nickel, copper and zinc in fine particles will help authorities improve health care and preventative strategies.
Regular air samples taken throughout Mexico City are analysed using a technique known as PIXE (proton induce x-ray emission). The IAEA is providing around $300,000 in equipment and training to scientists at the National Nuclear Research Institute of Mexico (ININ) who conduct the analysis. The scientists use an accelerator to shoot a beam of protons at a dust sample collected from the air. The results of the reaction reveal a wealth of information which helps scientists to pinpoint the exact source of toxic emissions. That's valuable information in a city where industry and the city's 20 million inhabitants often live side by side. Importantly, it gives decision makers and regulators better information on which to act and develop laws to control harmful emissions - all part of the effort to help Mexico City breathe easier.