Uh-oh, it looks like some (many?) new or fairly new kitchen cabinets are outgassing several types of PCBs from the wood sealants used on the cabinets. PCBs (polychlorinated biphenyls) were banned in the 1970s due to health risks - for example, they are known carcinogens, and some are neurotoxic (also here).
Researchers from the University of Iowa monitored air inside and outside 16 Iowa homes and found 3 types of PCBs (PCB-47, PCB-51, and PCB-68) wafting off the finished kitchen cabinets. They suggest that the PCBs becoming airborne are "unintentional impurities", that is, inadvertent byproducts of polymer sealants (from the common ingredient 2,4-dichlorobenzoyl peroxide) used in modern kitchen cabinetry. They found that unfinished cabinets had no PCB emissions. The concentrations seemed to be dependent on the year the house was built - with higher levels in houses built in the past 5 years (one house had just been completed), and also in a recently remodeled kitchen (new cabinets!). The cabinets were made by different manufacturers.
So now we have a new source of indoor air pollution to think about. The big questions are: 1) What, if anything, does this mean for human health? 2) How long does this outgassing from sealants go on for? 3) Are there alternative sealers that don't have this problem? By the way, the researchers discuss that household paints emit PCBs (such as PCB 11) as byproducts of paint pigment manufacturing, and yes, they were found both inside and outside houses. We love our plastics, use them in so many products, but there are consequences. From Env. Health News:
Researchers tested indoor air at 16 homes and found three types of PCBs are widespread, and finished cabinets are the source of the toxics, according to a study released today. They suspect the PCBs [polychlorinated biphenyls] are byproducts of sealants used on the cabinets. The study, from the University of Iowa, is the first to suggest wood finishing products are a significant source of PCBs to indoor air and finds that, despite federal bans on PCBs, the chemicals are still being released into the environment, including our homes. ...continue reading "Kitchen Cabinet Sealants Can Be A Source of Indoor Air Pollution"