Journal Article: Average Method Blank Quantities Of Dioxin-Like Congeners And Their Relationship To The Detection Limits Of The U.S. EPA's National Dioxin Air Monitoring Network (Ndamn)
The U.S. EPA established a National Dioxin Air Monitoring Network (NDAMN) to determine the temporal and geographical variability of atmospheric CDDs, CDFs and coplanar PCBs throughout the United States. Currently operating at 33 stations, NDAMN has, as one of its tasks, the determination of atmospheric levels of dioxin-like compounds at rural and non-impacted locations of the U.S. At the extremely low levels of detection needed to achieve congener-specific detection limits of 0.1 fg/m3 for 2,3,7,8-TCDD and 10 fg/m3 for OCDD, a number of analytical issues have been raised. One of these issues is the quantity of congeners to be expected in the laboratory method blanks. This paper presents the average, standard deviation, median, range, and detects of the quantities of the congeners from 52 laboratory sample sets. These values enable the accurate determination of the dioxin-like compounds at extremely low levels.