ISSN:
1573-5117
Keywords:
tubificidae
;
bioaccumulation
;
artificial sediment
;
risk assessment
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Lipophilic chemicals entering aquatic ecosystems often tend to adsorb to sediments. Although often not bioavailable to pelagic organisms, these compounds can be subject to bioaccumulation and thus pose a potential threat for sediment-dwelling organisms. The assessment of bioaccumulation is currently based on the extrapolation of fish bioconcentration data. Thus, measuring the bioaccumulation in benthic organisms gives more detailed information on the hazard of chemicals for aquatic ecosystems. The freshwater tubificids Tubifex tubifex and Limnodrilus hoffmeisteri were chosen as test organisms. Breeding of the oligochaetes as well as bioaccumulation studies were carried out in a system consisting of artificial sediment and reconstituted water. 14C-lindane (γ-hexachlorocyclohexane, γ-HCH) and 14C-hexachlorobenzene (HCB) served as model substances. Additionally, 14C-3,4-dichloroaniline (3,4-DCA) was tested. Uptake and elimination of lindane and HCB were examined. Bioaccumulation factors (BAF) were determined from the ratio of concentration in oligochaete tissue to concentration in sediment. The tubificids accumulated 14C-lindane, 14C-HCB, and 14C-3,4-DCA by factors of 4.7 (mean value; n = 4), 6.6 (mean value; n = 4) and 13.2, respectively, based on wet weight and radioactive concentrations. No major metabolites were detected in worms, sediment and water. Elimination kinetics were examined for 14C-lindane and 14C-HCB. When transferred to clean sediment, the worms eliminated both test substances rapidly and nearly completely. The tubificid bioaccumulation factors are contrasted with corresponding fish bioconcentration factors from literature. The presented data indicate once more that the assessment of bioaccumulation based exclusively on lipophilicity and on the extrapolation of fish bioconcentration data to other organisms or environmental compartments is not appropriate.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1003723831588
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