Our method for the analysis of the brominated flame retardants measured in this study is reported in Stapleton et al. (23 (link)). The analysis of the foam and dust samples for the organophosphate compounds is briefly outlined here. Approximately 0.3 to 0.5 grams of sieved dust was accurately weighed, spiked with 50 to 100 ng of two internal quantification standards (4’fluoro-2,3’,4,6-tetrabromodiphenyl ether (F-BDE 69) and 13C-labeled decabromodiphenyl ether (13C BDE 209)), and extracted in stainless steel cells using pressurized fluid extraction (ASE 300, Dionex Inc.). Cells were extracted three times with 50:50 dichloromethane:hexane at a temperature of 100°C and at 1500 psi. Foam samples of approximately 0.2–0.3 grams in weight were also extracted using the same solvents on the ASE system but no internal standards were spiked into the ASE cell. Final extracts were reduced in volume to approximately 1.0 mL using an automated nitrogen evaporation system (Turbo Vap II, Zymark Inc.). Foam sample extracts of approximately 3.5 mL in volume were then accurately weighed in a 4 mL amber vial and a 50 µL aliquot was transferred to an autosampler vial, spiked with 100 ng of a carbon-labeled chlorinated diphenyl ether (13C CDE 141), and prepared for gas chromatography mass spectrometry (GC/MS) analysis. Dust extracts were purified by elution through a glass column containing 4.0 g of 6% deactivated alumina. All analytes were eluted with 50 mL of a 50:50 mixture of dichloromethane:hexane. The final extract was then reduced in volume to 0.5 mL and 50 ng of the recovery standard, 13C CDE 141, was added prior to GC/MS analysis. For the foam extracts, an aliquot of the extract was transferred to an autosampler vial and spiked with the recovery standard and analyzed by GC/MS.