It's fair to say most bosses want their employees to have high productivity.
Unfortunately, the air that office workers breathe may put a damper on quick thinking and fast work.
A new study found increased concentrations of fine particulate matter, called PM2.5, and lower ventilation rates were linked to slower response times and reduced accuracy.
"PM2.5 is a very nasty pollutant. It can account for 9 million deaths globally," said lead author Jose Guillermo Cedeno Laurent, a research fellow in the environmental health department at Harvard T.H. Chan School of Public Health.
Cedeno Laurent said PM2.5 concentrations are already associated with neurodegenerative decline such as in Alzheimer's disease, dementia and Parkinson's disease, but those studies mostly focused on older adults and on exposures that could be considered chronic or long-term.
"In this case, what we found was those effects to be present in a much younger population," Cedeno Laurent said. The mean age of the study participants was 33, in their prime age for productivity. But "whenever daily concentrations or immediate concentrations were going up, cognitive function was going down," he said.
The one-year study included more than 300 office workers between ages 18 and 65 in cities in China, India, Mexico, Thailand, the United Kingdom and the United States. Each of the workers had a permanent workstation in the office and worked at least three days a week.
The study used carbon dioxide (CO2) concentrations as a proxy for ventilation.
Researchers installed an environmental sensor at each workstation to monitor PM2.5 concentrations, CO2, temperature and relative humidity. Participants also had a custom-designed app on their phones. Researchers could administer cognitive tests and surveys through the apps.
The team would prompt the workers to participate in tests and surveys at prescheduled times and when levels of CO2 and PM2.5 exceeded or fell below certain thresholds.
Participants took two types of tests. One asked them to identify the color of displayed words, testing their cognitive speed and the ability to focus on what was relevant when something irrelevant was also presented. The other test assessed their cognitive speed and working memory on basic math questions.
When PM2.5 and CO2 levels were up, responses on the color test were slower and less accurate. Increases in CO2 were also associated with slower responses to the math questions.
Participants answered fewer questions correctly when levels of both PM2.5 and CO2 increased.
The study found impaired cognitive, or mental, function at concentrations that are common in indoor environments. Cedeno Laurent called this an important area of research given how much time people spend indoors, especially those who work in indoor offices.
Cedeno Laurent said the negative health effects of PM2.5 are attributed to inflammation. Past research has shown that these particles can cross the blood-brain barrier, a membrane that protects the brain, he noted.
Opening a window wouldn't help. The pollution inside offices is predominantly outdoor pollution, Cedeno Laurent said.
"In very air-polluted cities, what you would have to rely on is mechanical ventilation that has a higher level of filtration," he said.
Investing a little more to retrofit buildings to make them more energy efficient — and less likely to allow outside air indoors — would help, Cedeno Laurent said.
The idea of good ventilation is a hot topic now because of COVID-19. More attention to ventilation would benefit employees concerned about their office air quality.
COVID has made people more aware of how the environment and people around you can impact your everyday health, said Caitlin Donovan, senior director of public relations for the National Patient Advocate Foundation.
"Especially right now, there's hopefully so many offices that are upgrading their air filtration systems anyway because of COVID, so hopefully that's a positive first step," said Donovan, who was not involved in the study. "But as we can tell from the news every day, there's not complete buy-in and I'm sure that's an expensive process."
What if your employer does not intend to upgrade the air system?
It's possible that future legislation could be helpful in requiring cleaner office air, suggested Donovan, whose organization works to help eliminate obstacles for patients who need health care.
"There's always going to be buildings that don't get upgraded," Donovan said. "And then there's always people and, more likely than not, people who are lower income or historically excluded, who are still going to be the worst off."
The study was published online Sept. 9 in Environmental Research Letters.