Bioaccumulation of hexachlorobenzene in Eisenia foetida at different aging stages

• Published in: Journal of environmental sciences (China) 2009, Vol.21 (7), p.948-953
• Main Author: GAO, Hongjian
• Format: Article
• Language: English
• Subjects: Aging; Animals; bioavailability; Biodegradation, Environmental; earthworm; Eisenia foetida; Environmental Monitoring; extractability; HCB; Hexachlorobenzene - metabolism; Oligochaeta - metabolism; soil; Soil Pollutants - metabolism; 孵化时间; 快速老化; 接触时间; 氯代苯; 蓄积性; 蓄积系数
• ISSN: 1001-0742; 1878-7320
• DOI: 10.1016/S1001-0742(08)62366-9

The impacts of contact time on the extractability, the availability of bexachlorobenzene （HCB） in different soils （paddy soil, red soil, and fluvo-aquic soil） and bioaccumulation in earthworm Eisenia foetida were investigated under controlled conditions in laboratory. Results indicated that the aging rate of HCB displaying a biphasic character in different soils： a rapid aging in the first 60 d followed by a slow aging in the next 120 d incubation time. Moreover, most of extractable HCB （about 90%） decline occurred in the first 60 d after HCB was spiked into the soils. The aging rate of HCB in the paddy soil was higher than that in the fluvo-aquic soil or the red soil. The amount of HCB accumulated in the earthworms and its accumulative ability, expressed as a bioaccumulation factor （BAF）, declined as the aging time increased from 1 to 180 d. Although the extractable HCB decreased with increasing residence time in soil, much of HCB could still be accumulated by earthworms （457.6-984.3 ng/g） through bioaccumulation, which poses a potential risk to soil ecological safety.