Dechlorane plus in the Global Atmosphere

Abstract

Dechlorane plus (DP) is a high-production volume chlorinated flame retardant, which is under consideration for listing under the Stockholm Convention on Persistent Organic Pollutants. In this study, we provide additional and timely information to help evaluate the spatial and temporal trends and long-range transport potential of DP at 67 sampling sites. The Global Atmospheric Passive Sampling network has been deploying passive air samplers quarterly since 2005. A retrospective analysis of samples from 2005 and 2006 indicates that DP is globally distributed in air with total DP levels ranging from nondetect to 30 pg/m3. The median value at urban sites (∼0.9 pg/m3) was approximately 10 times greater than at background, rural, and agricultural sites. The anti-DP/syn-DP ratio was relatively consistent across most site categories and in the range of values measured in commercial products containing DP. This suggests that both isomers are about equally capable of long-range transport in air. A retrospective analysis for selected sites covering the period of 2005-2011 showed declining levels of DP at urban sites in Paris and Toronto.