Exhaust harms drivers' hearts Study of cops in cars gives particle pollution warning. 27 April 2004
HELEN PEARSON Exhaust particles are sucked into cars © Getty Images People could be suffering from poisonous dust inside their vehicles, according to a US study. The result highlights the need for strict controls on exhaust emissions. Many studies have suggested that the air in cars is almost as filthy as that on the roads, but few have linked this directly to drivers' health. Robert Devlin at the Environmental Protection Agency in Research Triangle Park, North Carolina, and his colleagues tracked nine local police patrol officers on late night shifts. Over four days, the researchers monitored levels of pollutants in the officers' cars and then measured the fitness of their hearts next morning. They found that tiny particles called PM2.5, which are spewed out in vehicle exhausts and sucked into the car, appear to interfere with drivers' hearts. The higher the troopers' exposure on a nine-hour shift, the more likely they were to suffer irregular heartbeats and increased levels of blood-clotting proteins, that may indicate a risk of cardiovascular disease. 1 Although overall particle levels are higher outside the car than in, Devlin believes those that work their way into the car are particularly potent. Other pollutants, such as ozone and carbon monoxide, were present in the automobiles but were not strongly linked with health problems in the study. There is no evidence of a safe level Douglas Dockery Harvard School of Public Health It is too early to say whether the troopers will suffer long-term effects. And it is not known whether truck drivers or commuters also accumulate enough exposure to the particles to be harmed, says team member Michael Riediker of the Institute of Occupational Health Sciences in Lausanne, Switzerland. But the study adds to a stack of evidence that PM2.5 particles, which are also emitted from power plants and other fuel-burning industries, are toxic. An estimated 500,000 people die each year from inhaling the microscopic polluting particles. "It is a pretty serious health problem," says Devlin. Dusty answers? Some efforts have already been made to control PM2.5: many countries have air quality standards, while clean fuels and modern engines all help reduce vehicle emissions. But in the US, levels of PM2.5 could be cut further by phasing out or cleaning up old diesel buses and trucks, says Douglas Dockery who studies air pollution at Harvard School of Public Health in Boston. "There is no evidence of a safe level," he says. Until polluting particles are removed at source, people can take small steps to reduce their exposure. Last year in the US, the Environmental Protection Agency started issuing daily alerts on particle pollution, which they hope will be incorporated into weather forecasts to warn people when levels are high. Devlin emphasises that those potentially at risk from the particles are those already vulnerable to heart disease, such as the elderly. On 'bad air' days, he suggests, they should avoid long car journeys or exercise, which encourages inhalation of the particles. People should also note that making the car recycle its air does not eliminate the problem because a fraction is still sucked in from outside. References 1. Riediker, M. et al. American Journal of Respiratory and Critical Care Medicine, 169, 934 - 940, (2004). © Nature News Service / Macmillan Magazines Ltd 2004 ------------------------ Yahoo! Groups Sponsor ---------------------~--> Make a clean sweep of pop-up ads. Yahoo! Companion Toolbar. Now with Pop-Up Blocker. Get it for free! http://us.click.yahoo.com/L5YrjA/eSIIAA/yQLSAA/FGYolB/TM ---------------------------------------------------------------------~-> Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Biofuels list archives: http://infoarchive.net/sgroup/biofuel/ Please do NOT send Unsubscribe messages to the list address. To unsubscribe, send an email to: [EMAIL PROTECTED] Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/biofuel/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
