Atmospheric transport and deposition of polychlorinated dibenzo-p-dioxins and dibenzofurans

Atmospheric transport and deposition of polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzodifurans (PCDFs) were studied by determining their concentrations in ambient air and rain samples collected in Bloomington, IN. Total concentrations in ambient air range from tens of picograms (pg)/m super(3) for urban sites to tenths of pg/m super( 3) for rural locations. The average total concentration in rain from a suburban area was 90 pg/l. The total washout ratio was in the 9300-90,000 range, and the Henry's law constants were in the 1.5 x 10 super(-5) to 9 x 10 super(-8) atm m super(3)/mole ranges. Comparisons of PCDD/PCDF profiles with other environmental compartments show a consistent, systematic change from a combustion source profile to a sedimentary sink profile.