A critical evaluation of safety (uncertainty) factors for ecological risk assessment

Chapman, PM

HERO ID

6302782

Reference Type

Journal Article

Year

1998

Language

English

HERO ID 6302782
In Press No
Year 1998
Title A critical evaluation of safety (uncertainty) factors for ecological risk assessment
Authors Chapman, PM
Journal Environmental Toxicology and Chemistry
Volume 17
Issue 1
Page Numbers 99-108
Abstract Evaluation of environmental risks posed by potentially hazardous substances requires achieving a balance between over- and underprotection. i.e., between societal benefits posed by the use of particular substances and their potential risks. Uncertainty (e.g., only laboratory data may be available, field or epidemiological data may be limited and less than clear-cut, etc.) will always exist and is often conservatively dealt with by the use of so-called "safety" or "uncertainty" factors, some of which remain relatively little changed since their origin in 1945. Extrapolations involving safety factors for both aquatic and terrestrial environments include inter-and intraspecies, acute-to-chronic, lowest-to no-observed-effect concentration (NOEC), and laboratory-to-held extrapolation (e.g., extrapolation of laboratory results to the field). To be realistic, such extrapolations need to have a clear relationship with the field effect of concern and to be based on good science. The end result is, in any case, simply an estimate of a field NOEC, not an actual NOEC. Science-based versus policy-driven safety factors, including their uses and limitations, are critically examined in the context of national and international legislation on risk assessment. Key recommendations include providing safety factors as a potential threshold effects range instead of a discrete number and using experimental results rather than defaulting to safety factors to compensate for lack of information. This latter recommendation has the additional value of rendering safety factors predictive rather than simply protective. We also consider the so-called "Precautionary Principle," which originated in 1980 and effectively addresses risk by proposing that the safety factor should be infinitely large.
Doi 10.1897/1551-5028(1998)017<0099:ACEOSU>2.3.CO;2
Wosid WOS:000071120200012
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English
Keyword safety factors; ecological risk assessment; uncertainty factors; assessment factors; precautionary; principle