A recent study in America found evidence for increased levels of IL-1 beta, a marker associated with inflammation in the blood of people who lived near the highways and had high exposures to vehicular exhausts.
As our consumption and usage of vehicles increases, our roads constantly brew more particulate matter, black carbon, nitrogen dioxide, sulphur-di-oxide and carbon monoxide, all emitted from automobile exhausts. The danger about these emissions is that they don’t just stay there, but drift. Our busy highway and motorways, which have high traffic volume, are the worst offenders. Studies indicate that people living/working in such areas and spending significant time within approximately 200m of highways are exposed heavily to these pollutants compared to people who are based further away. Unsurprisingly, the exposures at highways are higher when compared to people living on busy urban streets.
Inflammation plays a crucial role in the development and progression of a variety of heart diseases importantly atherosclerosis and congestive heart failure. Inflammatory molecules linked to these processes includes interleukin-1 (IL-1), but this American study is the first of its kind where such a link has been shown to occur in humans with proximity to heavy traffic. The results are notable as it also recapitulates the trend shown by particulate matter in increasing the levels of IL -1 family in animal models and cells in culture. In their paper, the researchers also point out that IL-1 beta itself could have application as a biological marker of air pollution exposure. However, one thing to note is that IL-1 family is also influenced by diet and this is a factor that has to be controlled for in further experiments. Cumulatively, the study by Professor Brugge and his colleagues is a very interesting preliminary work which warrants larger carefully controlled follow up studies.