Organophosphate ester flame retardants and plasticizers in the indoor environment: Analytical methodology and occurrence

Nine organophosphate esters, which are commercially used as plasticizers and/or flame retardants, were identified and quantified in air samples from some common indoor work environments, i.e., an office building, a day care center, and three school buildings. One of the compounds was identified as tri(2-chloroethyl) phosphate, a substance that has been shown to be a neurotoxic and genotoxic agent. The concentration levels of this substance were found to be as high as 250 ng/m(3). In order to examine whether the organophosphates were transferred from the outdoor air, the occurrence of organophosphates in outdoor ambient air was investigated. The levels of the individual compounds in the outdoor air samples were found to be less than 1 ng/m(3), which indicates that the main sources of organophosphates in indoor air were located indoors. A comparison between the studied indoor environments showed large differences in the concentration profiles of the nine identified compounds. This was most probably due to the large variation in indoor materials, furniture, and equipment between the different indoor work environments. A method for sampling and analysis is described and evaluated. Samples were collected by pumping air through filter and polyurethane foam plugs. At a low sampling rate, 3 L/min, the organophosphates were strongly associated with the filter, by polar interactions either directly to the filter or to the particulate phase adsorbed on the filter. Ultrasonication was shown to be a fast and efficient extraction method for all of the organophosphates studied.