photo credit; John Liu

Phosphate flame retardants (PFRs) are commonly used and often found in household dust. Studies have shown that human exposure to older flame retardants often occurs through inhalation or ingestion of household dust resulting in a correlation between the amount of flame retardants present in dust and the amount of flame retardants present in human biological samples such as urine. However, there have been very few studies investigating whether or not this association exists for PFRs as well. A recent study in Environmental Science & Technology addressed this question and found that the correlation between phosphate flame retardants in household dust and the urine of the people who lived in those homes was relatively low. Researchers sampled dust and urine from 16 non-smoking adults from California and the homes that they live in. Samples were taken in 2006 and again in 2011 to see if the addition of new electronics to the home increased levels of PFRs found in dust. Researchers found that the level of PFRs in household dust was only weakly correlated with human exposure. However, individuals who had recently renovated their homes did test positive for higher PFRs, suggesting that some exposure was likely occurring through dust. The authors suspect that the weak correlations between household dust in this study may be due to additional exposures in the workplace or automobile. Future studies should collect data on additional exposure routes, and with a larger number of participants.