KEY POLLUTANTS - THE IMPACT ON HEALTH

摘要

Air pollution is not a problem of the past. Though the concentrations of many air pollutants continue to fall in the UK they still have a significant impact on health. How large this impact is has only been realised during the past ten or so years. That levels of pollutants, that are low in comparison to levels recorded in the 1950s and earlier, continue to damage health has come as an unwelcome surprise to many, including policy makers. Explaining how low concentrations of pollutants affect health is a challenge to the research community: mechanisms of effect are beginning to appear but much remains to be discovered. Current appreciations of the effect on health of classical air pollutants including nitrogen dioxide, sulphur dioxide, particulate matter, carbon monoxide and ozone, depend upon modern techniques of epidemiological research. These techniques, which are powerful and able to detect small effects, depend upon the power of modern computers and, though the theory was understood, their application was not possible for most research workers before about 1980. The methods involve handling large data sets and the application of complex methods of regression analysis. Dealing statistically with the many confounding factors that obscure and interact with the effects on health of air pollutants is possible using these methods. Early concerns about the adequacy of handling confounding factors have recently been allayed.