Persistent Organic Pollutants in Dusts That Settled at Indoor and Outdoor Locations in Lower Manhattan after September 11, 2001

摘要

During the initial days that folLowed the explosion and collapse of the World Trade Center (WTC) on September 11, 2001, fourteen bulk samples of settled dusts were collected at locations surrounding the epicenter of the disaster, and analyzed for persistent organic pollutants, including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and select organo-chlorine pesticides. The PCBs comprised less than 0.001% by mass in three outdoor samples analyzed, indicating that PCBs were of limited significance in the total settled dust across Lower Manhattan. Likewise, organo-chlorine pesticides, were found at low concentrations in the bulk samples. Conversely, the PAHs comprised up to nearly 0.04% by mass of the settled outdoor dust in the six samples. Further size segregation indicated that the PAHs were found in higher concentrations on relatively large particles (10-53 μm). Significant concentrations were also found on fine particles (< 2.5 μm), often accounting for ～ 0.005 % by mass. Twelve bulk samples of the settled dust were also collected at indoor locations surrounding the epicenter of the disaster. Concentrations of PCBs comprised less than one ppm by mass in the two indoor dust samples. The organo-chlorine pesticides were found at even Lower concentrations in the indoor samples. The PAHs comprised up to 0.04% by mass of the indoor dust in the eleven WTC impacted indoor samples. Comparison of PAH concentration patterns shows that the dusts that settled indoors are chemically similar to dusts found at outdoor locations. Analysis of one sample of indoor dusts collected from a vacuum cleaner of a rehabilitated home shows markedly Lower PAH concentrations (< 0.0005 mass %), as well as differing relative contributions for individual compounds. These PAH analyses may be used in identifying dusts of WTC origin at indoor locations, along with ascertaining further needs for cleaning.