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Don't be fooled-A no-observed-effect concentration is no substitute for a poor concentration-response experiment
David R Fox1,2, Wayne G Landis3
1Environmetrics Australia, Beaumaris, Victoria, Australia.
Environmental Toxicology and Chemistry
|April 19, 2016
Summary
The study argues against the continued use of no-observed-effect concentrations (NOECs) in ecotoxicology, refuting recent claims that support their retention. It emphasizes that NOECs are a poor toxicity measure and models are preferable for concentration-response relationships.
Area of Science:
- Ecotoxicology
- Environmental Science
- Risk Assessment
Background:
- The use of no-observed-effect concentrations (NOECs) in ecotoxicology has been debated for decades.
- Critics argue NOECs are a poor toxicity measure, advocating for concentration-response models instead.
- Recent arguments support NOEC retention for weak or absent concentration-response relationships, or when models are unavailable.
Purpose of the Study:
- To counter recent claims supporting the use of NOECs in ecotoxicology.
- To provide new insights into modeling challenges where NOECs are claimed to be necessary.
- To advocate for the long-overdue discontinuation of NOEC use in favor of scientifically sounder methods.
Main Methods:
- Critical analysis of recent arguments defending NOEC use.
- Development of modeling approaches for previously intractable ecotoxicological problems.
- Review of historical and contemporary literature on NOECs and concentration-response modeling.
Main Results:
- Recent justifications for NOEC use were found to be incorrect.
- New modeling insights were developed for a class of problems previously thought unsuitable for such approaches.
- The study reinforces the scientific consensus against the use of NOECs.
Conclusions:
- The continued use of NOECs in ecotoxicology is scientifically unjustified.
- Models for concentration-response relationships are universally applicable and preferable to NOECs.
- Further research is expected to yield additional insights supporting the abandonment of NOECs.
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