Equivalence of concentration–response relationships in aquatic toxicology studies: Testing and implications for potency estimation

Oris, James T.; Bailer, A. John

doi:10.1002/etc.5620161031

Cited by 34 publications

(41 citation statements)

References 5 publications

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“…Fourth, equivalence of concentration-response relationships with and without predator cues was examined using the methods described in Oris and Bailer [32]. Briefly, a series of hypotheses related to parameters of the relationship from the logistic regression (i.e., b 1 or b 0 ) were tested.…”

Section: 02 (Sas Institute)mentioning

confidence: 99%

Effects of predator cues on pesticide toxicity: Toward an understanding of the mechanism of the interaction

Qin

Presley

Anderson

et al. 2011

Enviro Toxic and Chemistry

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Pesticide toxicity may be modified by a number of co-occurring environmental and ecological stressors. Coexposure to predator cues has been shown to potentiate and/or synergize toxicity of pesticides. However, the mechanisms behind these interactions are not well understood. Here we examine the effects of fish predator (bluegill, Lepomis macrochirus) cues on toxicity of five different pesticides to the freshwater cladoceran, Ceriodaphnia dubia. The purpose for examining patterns among pesticides was to test the idea that the mechanism of the interaction could be explained by a general stress response; that is, the interaction patterns would be similar regardless of the pesticide's mechanism of action [MOA]). Acute 96-h concentration-response experiments were conducted for pesticides with and without fish cues. Predator cues influenced the toxicity of pesticides and the interaction patterns varied among pesticides. Fipronil exhibited a synergistic interaction, while predator cues interacted antagonistically for bifenthrin and thiacloprid. Other compounds previously reported to potentiate toxicity (malathion) were found to act additively. The results demonstrate that factors such as pesticide bioavailability, K(OC) , and exposure concentration may be important for predicting the occurrence of these interactions and that patterns were not consistent among pesticides varying in MOA. Predator stress is an important component for structuring communities and ecosystem processes. Fully understanding how this process may interact with organic contaminants may best be achieved by examination at toxicokinetic and toxicodynamic scales.

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Section: 02 (Sas Institute)mentioning

confidence: 99%

Effects of predator cues on pesticide toxicity: Toward an understanding of the mechanism of the interaction

Qin

Presley

Anderson

et al. 2011

Enviro Toxic and Chemistry

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“…3), activity was calculated based on the EC 20 values using REP range and the point of departure (Moore and Caux, 1997;Oris and Bailer, 1997;Putzrath, 1997;Villeneuve et al, 2000). When this method was applied, the H4IIE cells were found to be sufficiently sensitive to determine TCDD-EQs in sediment extracts.…”

Section: Tcdd-eq Calculationmentioning

confidence: 99%

AhR-active compounds in sediments of the Haihe and Dagu Rivers, China

Song

Jiang

et al. 2006

Chemosphere

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Total concentrations of compounds that can cause activation of the aryl hydrocarbon receptor (AhR) in extracts of river sediments from various locations in the Haihe and Dagu Rivers, Tianjin, China were determined by use of the in vitro H4IIE-luc cell line. AhR-active compounds were isolated from sediments by Soxhlet extraction, and the crude extracts were fractionated using a Florisil column into three Fractions. The response of samples was compared to the TCDD standard and expressed as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) equivalents (TCDD-EQs). Significant dioxin-like activity was observed in each sample. The TCDD-EQs in crude extracts of sediments (SCEs), as determined with the bioassay were 2-4 times greater than the sum of the TCDD-EQs of the eluent from fractions separated with a Florisil column. The results also showed that Fractions 2 and 3 contained most of the AhR-mediated activity. The results obtained by using the bioassay were compared with those of previous measurements of the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) and the structurally-similar AhR-active polychlorinated biphenyls (PCBs). It was determined that sediments from the Dagu River contained greater concentrations of TCDD-EQ than did sediments from the Haihe River except at Jingangqiao (location R3), which is associated with industrial activities in the adjacent densely populated area. The concentrations of TCDD-EQs, based on the EC 20 and the relative potency ranges, of SCEs ranged from 330 to 930 and 1200 to 13 900 pg TCDD-EQ g À1 dry wt in Haihe and Dagu Rivers, respectively.

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“…is fitted to the data (for examples see Finney, 1964;Kerr and Meador, 1996;Oris and Bailer, 1997). The ED50s from the test extract are compared to the ED50 of the TCDD standard to determine the TCDD-EQ.…”

Section: F Data Analysismentioning

confidence: 99%

“…Depending on where the point estimate is taken from on the curve (e.g., EC20, EC50, or EC80), the TCDD-EQ of the sample will be different if the slopes of the standard and the extract are not parallel. Tests of dose-response curve parallelism are rarely reported in aquatic toxicology studies that use point estimate comparisons (Oris and Bailer, 1997). Even if statistical tests of parallelism are used, Villeneuve et al (2000a) state that these are not meaningful for examining extract curves where no defined dose unit can be used (i.e., extract doses can only be expressed in terms of their dilution factor or gram equivalents; see Section A).…”

Section: F Data Analysismentioning

confidence: 99%

The H4IIE Cell Bioassay as an Indicator of Dioxin-like Chemicals in Wildlife and the Environment

Whyte

Schmitt

Tillitt

2004

Critical Reviews in Toxicology

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ABSTRACT:The H4IIE cell bioassay has proven utility as a screening tool for planar halogenated hydrocarbons (PHHs) and structurally similar chemicals accumulated in organisms from the wild. This bioassay has additional applications in hazard assessment of PHH exposed populations. In this review, the toxicological principles, current protocols, performance criteria, and field applications for the assay are described. The H4IIE cell bioassay has several advantages over the analytical measurement of PHHs in environmental samples, but conclusions from studies can be strengthened when both bioassay and analytical chemistry data are presented together. Often, the bioassay results concur with biological effects in organisms and support direct measures of PHHs. For biomonitoring purposes and prioritization of PHH-contaminated environments, the H4IIE bioassay may be faster and less expensive than analytical measurements. The H4IIE cell bioassay can be used in combination with other biomarkers such as in vivo measurements of CYP1A1 induction to help pinpoint the sources and identities of dioxin-like chemicals. The number of studies that measure H4IIE-derived TCDD-EQs continues to increase, resulting in subtle improvements over time. Further experiments are required to determine if TCDD-EQs derived from mammalian cells are adequate predictors of toxicity to non-mammalian species. The H4IIE cell bioassay has been used in over 300 published studies, and its combination of speed, simplicity, and ability to integrate the effects of complex contaminant mixtures makes it a valuable addition to hazard assessment and biomonitoring studies.

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Equivalence of concentration–response relationships in aquatic toxicology studies: Testing and implications for potency estimation

Cited by 34 publications

References 5 publications

Effects of predator cues on pesticide toxicity: Toward an understanding of the mechanism of the interaction

Effects of predator cues on pesticide toxicity: Toward an understanding of the mechanism of the interaction

AhR-active compounds in sediments of the Haihe and Dagu Rivers, China

The H4IIE Cell Bioassay as an Indicator of Dioxin-like Chemicals in Wildlife and the Environment

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