People who work long hours in the office end up with higher levels of some toxic chemicals in their blood.
- Newer buildings and newly renovated offices contain higher levels of PFCs in the air than do older buildings.
- The more time people spend in their offices, the more chemicals accumulate in their blood.
Many office workers are unknowingly exposed to significant levels of toxic chemicals which have been linked to reproductive, developmental, liver and immune problems in animals and people.
People who spend the most time at the office have the highest levels of polyfluorinated compounds (PFC) levels in their blood, found a new study, which also showed a direct link between chemical levels in the air of a person's workplace and the amount of PFCs in his/her blood.
More than 95 percent of Americans harbor PFCs in their bodies, according to national health survey data. The new findings help narrow down major sources of exposure, opening up potential ways to reduce the burden of chemicals in our bodies.
"When we think of occupational exposures, it's easy to think about construction workers or welders, but an even larger population is office workers," said Michael McClean, an environmental health scientist at the Boston University School of Public Health. "We wanted to look at those environments and see what was in the air."
PFCs are a group of chemicals that offer water-resistant and stain-resistant properties to a wide range of products, including carpets, furniture, food wrappings and nonstick pots and pans. Investigations have turned up significant levels of several PFCs in the environment and in people, but few studies have systematically considered where most of those chemicals come from.
McClean and colleagues decided to look at offices because people spend a lot of time at work, and because offices are full of stain-resistant furniture, paint, carpeting and other objects that can emit PFC-containing dust.
The team recruited 31 adults who live and work in Boston-area offices. About a quarter of their offices were in a new building that had been built the previous year and was decorated with brand new carpets, upholstered chairs and other furnishings. A quarter of workplaces were in older buildings with no recent history of renovation.
The remaining half of offices sat in a building that had been partially renovated the year before with new carpeting in the hallways and about 10 percent of rooms. All offices were painted from floor to ceiling, had closed-air ventilation, and at least one computer on a desk. And all had doors that were closed at night.
For a week during the winter, from 8 a.m. on a Monday to 8 a.m. on a Friday, air pumps collected particulate and gaseous matter from the air in each office. At the end of the week, researchers also collected blood and dietary information from every worker.
Levels of a chemical called FTOH were highest n the air of the new building and lowest in the air of the old one, the researchers reported in the journal Environmental Science & Technology. Our bodies break down FTOH into a PFC called PFOA.
When levels of FTOH were high in an office, people who worked in that office had higher levels of PFOA in their blood compared to people who worked in offices with lower levels. People who worked longer hours also inhaled more chemicals and accumulated higher levels of PFOA in their blood than did people who worked fewer days or shorter days.
Overall, the level of chemicals in the air of an office accounted for 36 percent of PFC levels in the blood.
"The fact that air in an office environment can explain more than a third of PFOA that you find in the blood," McClean said, "is actually pretty striking."
Scientists have long assumed that diet was the main source of PFCs in our bodies, said John Meeker, an environmental health scientist at the University of Michigan, Ann Arbor. Based the new findings, he said, it will now be useful to zero in on offices and figure out what it is about them that produces the most PFCs. The answers could lead to more regulations of products or safer renovation processes.
For now, it's too soon to offer advice to office-workers about how best to reduce their exposures.
"We're not going to tell people to stop going to the office," Meeker said.