Fixed‐effect‐level toxicity equivalents—a suitable parameter for assessing ethoxyresorufin‐<i>O</i>‐deethylase induction potency in complex environmental samples

Brack, Werner; Segner, Helmut; Möder, Monika; Schüürmann, Gerrit

doi:10.1002/etc.5620191015

Cited by 26 publications

(49 citation statements)

References 55 publications

(106 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, we used the 25% of the TCDD-induced maximum response being within the linear part of both the TCDD doseresponse curve and the sample extract volume-response curve. Our data are comparable to those of others that reported data on the 25% effect-level for estimation of TEQ of wastewater samples [32,33].…”

Section: Potential Of Wastewater On Ahr Transactivationsupporting

confidence: 90%

“…The estrogenic potentials of extracts were expressed as biological E2 equivalents (Bio-EEQ). The Bio-EEQs were calculated using the fixed-effect-level quantification method by estimating the sample volume needed to give the E2 effect at the 50% effect level [32,33]. The sample volume required to give the same response as E2-EC50 was designated as the 50% effective volume, EV50E2.…”

Section: Acartia Tonsa Early Life Stages Testmentioning

confidence: 99%

See 1 more Smart Citation

Endocrine potency of wastewater: Contents of endocrine disrupting chemicals and effects measured by in vivo and in vitro assays

Kusk

Krüger

Long

et al. 2010

Enviro Toxic and Chemistry

View full text Add to dashboard Cite

Industrial and municipal effluents are important sources of endocrine disrupting compounds (EDCs) discharged into the aquatic environment. This study investigated the endocrine potency of wastewater and the cleaning efficiency of two typical urban Danish sewage treatment plants (STPs), using chemical analysis and a battery of bioassays. Influent samples, collected at the first STP grate, and effluent samples, collected after the sewage treatment, were extracted using solid phase extraction. Extracts were analyzed for the content of a range of industrial chemicals with endocrine disrupting properties: phthalate metabolites, parabens, industrial phenols, ultraviolet screens, and natural and synthetic steroid estrogens. The endocrine disrupting bioactivity and toxicity of the extracts were analyzed in cell culture assay for the potency to affect the function of the estrogen, androgen, aryl hydrocarbon, and thyroid receptors as well as the steroid hormone synthesis. The early-life stage (ELS) development was tested in a marine copepod. The concentrations of all analyzed chemicals were reduced in effluents compared with influents, and for some to below the detection limit. Influent as well as effluent samples from both STPs were found to interact with all four receptors and to interfere with the steroid hormone synthesis showing the presence of measured EDCs. Both influent samples and one of the effluent samples inhibited the development of the copepod Acartia tonsa. In conclusion, the presence of EDCs was reduced in the STPs but not eliminated, as verified by the applied bioassays that all responded to the extracts of effluent samples. Our data suggest that the wastewater treatment processes are not efficient enough to prevent contamination of environmental surface waters.

show abstract

Section: Potential Of Wastewater On Ahr Transactivationsupporting

confidence: 90%

Section: Acartia Tonsa Early Life Stages Testmentioning

confidence: 99%

Endocrine potency of wastewater: Contents of endocrine disrupting chemicals and effects measured by in vivo and in vitro assays

Kusk

Krüger

Long

et al. 2010

Enviro Toxic and Chemistry

View full text Add to dashboard Cite

show abstract

“…Thus, potency of the samples to induce a dioxin-like response in the assays was converted to 2,3,7,8-TCDD equivalents (TEQs) based on relating the EC 25TCDD value of each triplicate measurement of the extract, i.e. the concentration of sample that causes 25% of TCDD-max, to the EC 25 of 2,3,7,8-TCDD (equation 1) [35]. Mean values and standard deviations of the TEQ values were calculated from independent triplicate assays. …”

Section: Methodsmentioning

confidence: 99%

Contribution of Priority PAHs and POPs to Ah Receptor-Mediated Activities in Sediment Samples from the River Elbe Estuary, Germany

et al. 2013

View full text Add to dashboard Cite

The estuary of the River Elbe between Hamburg and the North Sea (Germany) is a sink for contaminated sediment and suspended particulate matter (SPM). One major concern is the effect of human activities on the hydrodynamics, particularly the intensive dredging activities in this area that may result in remobilization of sediment-bound pollutants. The aim of this study was to identify pollutants contributing to the toxicological risk associated with re-suspension of sediments in the Elbe Estuary by use of an effect-directed analysis that combines chemical and biological analyses in with specific fractionation techniques.Sediments were collected from sites along the Elbe Estuary and a site from a small harbor basin of the Elbe Estuary that is known to be polluted. The sixteen priority EPA-PAHs were quantified in organic extracts of sediments. In addition, dioxin equivalents of sediments were investigated by use of the 7-ethoxyresorufin O-deethylase assay with RTL-W1 cells and the Ah receptor-mediated luciferase transactivation assay with H4IIE-luc cells.Quantification of the 16 priority PAHs revealed that sediments were moderately contaminated at all of the sites in the Elbe River Estuary (<0.02–0.906 µg/g dw). Sediments contained relatively small concentrations of dioxin equivalents (Bio-TEQ) with concentrations ranging from 15.5 to 322 pg/g dw, which were significantly correlated with dioxin equivalents calculated based on toxicity reference values and concentrations of PAH. The concentration of Bio-TEQ at the reference site exceeded 200,000 pg/g dw. In a potency balance the 16 PAHs explained between 47 and 118% of the Bio-TEQ in the luciferase assay, which can be explained by the constant input of PAHs bound to SPM from the upper course of the Elbe River into its estuary. Successful identification of a significant portion of dioxin-like activity to priority PAHs in complex environmental samples such as sediments has rarely been reported.

show abstract

“…In comparison, the levels of total PCDD/ Fs were much lower than those in sediments from Ya-Er Lake (China) (31) and those in Passaic River sediment (United States) (32). In the case of PCBs, the concentrations were 2 or 3 orders of magnitude lower than those from the sediment of the river Spittelwasser in the industrial region of Bitterfeld (Germany) (33) and those in the Ariake Sea (Japan) (27). From chemical data, the TEQcal ranged between 19.5 and 37.9 pg 24, 25, 27. d TEQcal is the sum of the TEQPCB, TEQPCDD/F, and TEQPAH.…”

Section: Concentration Levels and Teqcal From Chemical Analysismentioning

confidence: 84%

Identification of Ah Receptor Agonists in Sediment of Meiliang Bay, Taihu Lake, China

Qiao

Chen

Zhang

et al. 2006

Environ. Sci. Technol.

View full text Add to dashboard Cite

Deterioration of ecosystem and water quality in Taihu Lake, the third largest freshwater lake in China, is of great concern in China. However, most evaluations on water and sediment were carried out by chemical analysis, which could hardly gain information on the risk stressors affecting the system. Sediment samples from Meiliang Bay, Taihu Lake were assayed for AhR-mediated EROD induction using a rat hepatoma cell line (H4IIE). The known AhR agonists including PCDD/Fs, PCBs, and PAHs were analyzed by instruments. The cause-effect relationship between the observed EROD activity and chemical concentrations of AhR agonists and their dose-effect relationship were examined. Our results showed that sediment extracts could induce significant AhR effects, and the chemical-derived TCDD equivalents (TEQ cal ) were significantly correlated to bioassay-derived TCDD equivalents (TEQ bio ) (R ) 0.85, p < 0.01). Among different contributors, PAHs could account for 70-93% and PCDD/Fs could contribute less than 30% of TEQ cal . PCBs exhibited almost no contribution. Therefore, integration of EROD bioassay and chemical analysis provided an effective way for identifying the potential risk stressors. Under this circumstance, a quantitative doseeffect relationship between TEQ PAH and EROD activity could be established, suggesting that the observed AhR effect was mostly derived from PAHs. The implication is that the EROD assay and the identified risk stressors (PAHs) may be used in lieu of detailed environmental analysis to follow the progression of a remediation strategy.

show abstract

Fixed‐effect‐level toxicity equivalents—a suitable parameter for assessing ethoxyresorufin‐O‐deethylase induction potency in complex environmental samples

Cited by 26 publications

References 55 publications

Endocrine potency of wastewater: Contents of endocrine disrupting chemicals and effects measured by in vivo and in vitro assays

Endocrine potency of wastewater: Contents of endocrine disrupting chemicals and effects measured by in vivo and in vitro assays

Contribution of Priority PAHs and POPs to Ah Receptor-Mediated Activities in Sediment Samples from the River Elbe Estuary, Germany

Identification of Ah Receptor Agonists in Sediment of Meiliang Bay, Taihu Lake, China

Contact Info

Product

Resources

About