US EPA

2177762 

Journal Article 

EVALUATION OF A TECHNIQUE FOR MEASURING DRY AERIAL DEPOSITION RATES OF DDT AND PCB RESIDUES 

Murphy, TJ 

1981 

1 

Atmospheric Environment
ISSN: 1352-2310
EISSN: 1873-2844 

PESTAB/81/2104 

15 

2 

206-207 

WOS:A1981LD77800015 

PESTAB. A critical evaluation of a previously described technique for collecting dry aerial deposition (DAD) of chlorinated hydrocarbons (CHCs) is presented in this letter to the editor. The technique does not account for vapors and, therefore, the passive collector provides overestimates of DAD. No rationale is given for using mineral oil as the surface film; numerous arguments for various surface materials are considered. Mathematical proof is presented that leaving the collectors in place for 8 days is less efficient than replacing the collector daily for 8 days. Before the 8 day period is over the oil becomes saturated and no more vapors are scavanged, even though DAD could still be collected. Mathematical evidence for use of a polar collecting surface is also presented.