Environmental Health Laboratory Branch, California Department of Public Health, Richmond, CA 94804, USA.
Environ Int. 2013 Sep;59:16-26. doi: 10.1016/j.envint.2013.05.003. Epub 2013 Jun 2.
We characterized flame retardant (FR) morphologies and spatial distributions in 7 consumer products and 7 environmental dusts to determine their implications for transfer mechanisms, human exposure, and the reproducibility of gas chromatography-mass spectrometry (GC-MS) dust measurements. We characterized individual particles using scanning electron microscopy/energy dispersive x-ray spectroscopy (SEM/EDS) and Raman micro-spectroscopy (RMS). Samples were screened for the presence of 3 FR constituents (bromine, phosphorous, non-salt chlorine) and 2 metal synergists (antimony and bismuth). Subsequent analyses of select samples by RMS enabled molecular identification of the FR compounds and matrix materials. The consumer products and dust samples possessed FR elemental weight percents of up to 36% and 31%, respectively. We identified 24 FR-containing particles in the dust samples and classified them into 9 types based on morphology and composition. We observed a broad range of morphologies for these FR-containing particles, suggesting FR transfer to dust via multiple mechanisms. We developed an equation to describe the heterogeneity of FR-containing particles in environmental dust samples. The number of individual FR-containing particles expected in a 1-mg dust sample with a FR concentration of 100ppm ranged from <1 to >1000 particles. The presence of rare, high-concentration bromine particles was correlated with decabromodiphenyl ether concentrations obtained via GC-MS. When FRs are distributed heterogeneously in highly concentrated dust particles, human exposure to FRs may be characterized by high transient exposures interspersed by periods of low exposure, and GC-MS FR concentrations may exhibit large variability in replicate subsamples. Current limitations of this SEM/EDS technique include potential false negatives for volatile and chlorinated FRs and greater quantitation uncertainty for brominated FR in aluminum-rich matrices.
我们对 7 种消费品和 7 种环境灰尘中的阻燃剂（FR）形态和空间分布进行了表征，以确定它们对转移机制、人体暴露和气相色谱-质谱（GC-MS）灰尘测量的可重复性的影响。我们使用扫描电子显微镜/能量色散 X 射线光谱（SEM/EDS）和拉曼微光谱（RMS）对单个颗粒进行了表征。对样品进行了筛查，以确定 3 种 FR 成分（溴、磷、非盐氯）和 2 种金属增效剂（锑和铋）的存在。随后，对选定样品进行 RMS 分析，使 FR 化合物和基质材料的分子识别成为可能。消费品和灰尘样品中的 FR 元素重量百分比分别高达 36%和 31%。我们在灰尘样品中发现了 24 个含有 FR 的颗粒，并根据形态和成分将它们分为 9 种类型。我们观察到这些含有 FR 的颗粒具有广泛的形态，这表明 FR 通过多种机制转移到灰尘中。我们开发了一个方程来描述环境灰尘样品中含有 FR 的颗粒的异质性。在 FR 浓度为 100ppm 的 1mg 灰尘样品中，预计单个含有 FR 的颗粒数从<1 到>1000 个不等。高浓度溴颗粒的存在与通过 GC-MS 获得的十溴二苯醚浓度相关。当 FR 不均匀地分布在高浓度的灰尘颗粒中时，人体对 FR 的暴露可能表现为短暂的高暴露，随后是低暴露的时期，并且 GC-MS FR 浓度在重复的亚样本中可能表现出很大的变化。这种 SEM/EDS 技术的当前局限性包括对挥发性和氯化 FR 的潜在假阴性以及对富含铝的基质中的溴化 FR 的定量不确定性更大。
