Fig. 4From: Characterization of residential household dust from Shanghai by particle size and analysis of organophosphorus flame retardants and metalsEnrichment factors (EFs) of metals in household dust fractions. F2: 75–190 µm, F3: 25–75 µm, F4: cyclone 4–25 µm and F5e: 2.22 ± 2.04 µmBack to article page