Movement and Retention of Polychlorinated Biphenyls in a Paddy Field of WenTai Area in China

Abstract

Polychlorinated biphenyls (PCBs) are classi ed as priority pollutants by environmental agencies. A eld investigation on polychlorinated biphenyls movement and retention in paddy eld was conducted during 1993, 1997 and 1999 at the WenTai area. Soil, air and rice samples were analyzed. PCB concentrations in the soil showed a reducing trend with respect to time and depth. Most of the di-, tri-, and tetra-chlorinated PCB congeners showed signi cant decreases during the period, while the more highly chlorinated PCBs were more persistent in soil. The results of eld investigation data showed that even though 6 years the PCB concentrations in two elds were far from reaching uniform. In addition, rice grown in the eld appeared somewhat contamination by PCBs, but it was not likely subjected to concentrating PCBs from contaminated soil signi cantly. It was shown that the PCB concentrations in rice samples were not directly proportional to their concentrations in soil. Principal component analysis was performed with the standardized relative abundance of PCBs in the samples. All these observations indicated that the pattern of PCBs in soil cannot be considered to re ect the original pollution source.

Temporal trends of PCBs, PCDD/Fs and PBDEs in soils from an E-waste dismantling area in East China

“…CB-126 was the major contributor to the P TEQs of the PCBs (>90%). This result is similar to those reported by Bi et al 18 and Shen et al 19 in this area.…”

Evidence for the transfer of polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins, and polychlorinated dibenzofurans from soil into biota

“…The results of PCA also showed that soil samples were characterized by higher chlorinated PCBs, and plant samples were characterized by lower chlorinated PCBs. Chu et al (1999) and Bi et al (2002) also reported that PCBs 28 and 52 decreased, while PCBs 153 and 138 increased from 1993 to 1997 in background paddy soil.…”

“…It has been applied successfully by some researchers to group the samples or to reveal the proximity between the sources of these compounds (Chu et al, 1999;Bi et al, 2002;Smith et al, 1990;Koesters and Hites, 1992).…”

“…In 1989, illegal detaching of disused electric capacitors resulted in the PCBs pollution accident in southern China. Chu et al (1999) and Bi et al (2002) studied the PCB levels in paddy field near the pollution site in this region in 1993 and 1999.…”

Assessment of PCBs and PCDD/Fs Along the Chinese Bohai Sea Coastline Using Mollusks as Bioindicators

“…Lower concentrations of PCBs were detected in mollusks from China. However, a few researches reported that the PCBs pollutions in some regions of China were related to Chinese technical products of PCBs (Chu et al1999;Bi et al 2002). The domestic products of technical PCBs were named PCB 3 and PCB 5 , the compositions of which are similar to that of Aroclor 1242 and 1254, respectively (Jiang et al 1997).…”