The average American spends almost an hour each day commuting to work, a number that is rapidly increasing.
Now, research has found that commuters in California can be exposed to acceptable levels of unhealthy chemicals during their daily work trips.
By estimating commuter times from census data and using measurements of chemicals detected in previous studies, the new study found that commuting more than 20 minutes puts people at risk of unacceptably high levels of two carcinogens used in car manufacturing.
At first glance, this may seem like worrying news to people who spend a lot of time driving on the daily commute. But there are a lot of factors at play, so let’s unpack it a bit.
The distinct smell of a new car gives you a smell of what is happening here. The materials used to arrange the machines, from hard and soft plastics to adhesives, textiles and foam, contain some chemicals that can slowly leak into the air (the technical term is “release”) or can catch dust.
“These chemicals are very volatile, easily moving from plastics and textiles to the air you breathe,” said David Volz, an environmental toxicologist at the University of California Riverside who co-authored the study.
Volatile compounds can accumulate in small spaces, such as inside a car (unless you open a window for clean air).
Although much research to date has focused on outdoor air pollution and its impact on health and the environment, such as workplaces or homes where people spend most of their days, this study suggests that chemicals that Accumulating inside vehicles could also be a problem – for some drivers.
The study aimed to estimate when a person’s exposure to known carcinogens probably exceeded safety thresholds based on time spent by commuters in their vehicles and the levels of five chemicals detected in cars in previous studies.
The researchers predicted that commuters’ daily exposure to two of the five chemicals studied – benzene and formaldehyde – would probably exceed levels considered safe or allowed by California health authorities after 20 minutes. The probability continued to increase the longer a person’s commute.
The two chemicals of concern are not unknown huge, but they certainly deserve attention. Benzene is found in rubber and dyes, and formaldehyde is used in carpets and paints and both are included on the long list of carcinogens in Proposition 65 in California. The news here refers to the risk that these chemicals may pose especially to drivers.
“Our study raises concerns about the potential risk associated with inhaling benzene and formaldehyde for people who spend a significant amount of time in their vehicles, an issue that is particularly relevant for congested areas where people travel longer.” , the authors of the study wrote.
Perhaps surprisingly, a larger fraction of people had an increased chance (over 1 in 10) of exceeding the cancer risk thresholds for benzene and formaldehyde on the daily commute in the areas around San Francisco and Los Angeles, notoriously crowded. traffic.
“Of course, there is a range of exposures that depends on how long you are in the car and how many compounds your car emits,” which may depend on the age of the vehicle and the surrounding temperatures, said student and lead author Aalekhya Reddam. from the University of California Riverside.
In other words, just because something is listed as carcinogenic does not mean that it is guaranteed to cause health problems – it depends on the dose to which people are exposed and how often.
Even known carcinogens are not likely to cause cancer below certain thresholds, and limiting exposure to harmful substances helps reduce the associated risk.
In addition, the poor health outcomes seen among commuters – which include higher rates of cancer – can come from a combination of inactivity, obesity and shorter sleep, which often come with long journeys. These factors were not considered in this study.
Some people, however, have no choice but to travel by car – or maybe they are taxi drivers, whose job It is lead. To reduce the risk of exposure, more could be done during the vehicle manufacturing process to replace chemicals such as benzene and formaldehyde for less harmful alternatives, the researchers said.
“Because people with long journeys are already a vulnerable subpopulation, additional measures may need to be put in place to mitigate the potential cancer risks associated with benzene and formaldehyde exposure,” the duo wrote in their paper.
“There should be alternatives to these chemicals to achieve the same goals during vehicle manufacturing,” Volz added. “If so, they should be used.”
Improving access to public transport and bicycle networks could also give people more options to get to work, while adding incidental exercise to their travel and helping to alleviate traffic congestion that clogs the city’s roads.
The research was published in Environment International.