Abstract:
Abstract An innovative ex situ soil washing technology was developed to remediate
polybrominated diphenyl ethers (PBDEs) and heavy metals in an electronic waste site.
Elevated temperature (50° C) in combination with ultrasonication (40 kHz, 20 min) at 5.0 mL
L− 1 sunflower oil and 2.5 g L− 1 carboxymethyl chitosan were found to be effective in
extracting mixed pollutants from soil. After two successive washing cycles, the removal
efficiency rates for total PBDEs, BDE28, BDE47, BDE209, Pb, and Cd were approximately
94.1, 93.4, 94.3, 99.1, 89.3, and 92.7%, respectively. Treating the second washed soil with
PBDE-degrading bacteria (Rhodococcus sp. strain RHA1) inoculation and nutrient addition
for 3 months led to maximum biodegradation rates of 37.3, 52.6, 23.9, and 1.3% of the
remaining total PBDEs, BDE28, BDE47, BDE209, respectively. After the combined …