Even comparatively low levels of air pollution can shorten your life, according to a new British study.

The researchers looked at long-term air quality in different communities throughout Britain during time periods ranging from the mid-60s to the mid-90s and compared them to national data on causes of death. More than 5000 adults were included.

They discovered that breathing black smoke and sulfur dioxide were strongly linked to the risk of an early death. This was no surprise. But despite the fact that air quality in Britain improved greatly over the study period, the risk of early death from environmentally-caused lung disease remained fairly consistent, leading to the conclusion that even low levels of air pollution are very dangerous.

Published online in July 2007 ahead of print by the journal Thorax, these figures held true even after adjusting for factors known to increase the chances of premature death, including poverty and deprivation.

According to the researchers, this confirms the enduring legacy of air pollution on health and points to "continuing public health risks even at the relatively low levels of black smoke and sulphur dioxide that now occur."