Dechlorane Plus pollution and inventory in soil of Huai'an City, China

Dechlorane Plus (DP) has been used as a highly chlorinated flame retardant substituting those that are now internationally regulated under the Stockholm Convention. Nevertheless DP's environmental behavior has seldom been studied in China. There is only one DP manufacturer producing DP since 2005, which is located in Huai'an, Jiangsu Province. The DP levels in 21 soil samples that were taken from Huai'an in October 2009 and determined by gas chromatography/electron-capture negative ion-mass spectrometry (GC/ECNI-MS) method ranged from 0.83 to 1.2 x 10(3) ng g(-1), following a lognormal distribution. The geometric mean was 5.1 ng g(-1) dry weight (dw) and the geometric standard deviation was 4.6. Sampled soils had f(anti)[C(anti)(-DP)/(C(syn)(-DP)+C(anti)(-DP))] values of 0.67-0.85, with the average value of 0.79, which are close to the values in DP commercial products. This suggests that the main DP pollution source is the commercial DP product. The contour map of DP levels in soil indicated that the factory was the point pollution source with the highest DP level in its surrounding area, especially the southern area. A Monte Carlo based inventory estimation was conducted. The DP inventory in Huai'an is estimated to be 4-31 tons. To our knowledge, this study is the first that reports soil pollution by DP.