John Wiley & Sons, Ltd.

Estimating population‐level HC5 for copper using a species sensitivity distribution approach

Estimation of population‐level benchmark concentrations for protecting aquatic organisms from chemicals is important for value‐relevant ecological risk assessments. Here, by employing a species sensitivity distribution (SSD) approach, we aimed to derive the population‐level hazardous concentration for 5% of species (PHC5) for copper. Based on available information on copper toxicity and population models, we estimated population threshold concentrations at which the population size is stable (i.e., zero net population growth) for 13 freshwater species (three algal, six invertebrate, and four fish species). We then estimated the PHC5 for copper (6.8 µg/L; 95% confidence interval, 1.8 to 13.6 µg/L), by fitting a log‐normal distribution to the population threshold concentrations obtained. The close overlap between our estimate of the PHC5 and a field‐derived threshold concentration suggests that the population‐level SSD approach provides a reasonable level of protection for species richness in the natural environment. By contrast, and counterintuitively, our estimate was comparable with the individual‐level HC5 reported in the European Union risk assessment. Although the present study cannot determine the underlying reasons for the similar figures, the result provides an indication that the margin between individual‐level and population‐level benchmarks derived from SSD approaches can be very small. Our results therefore suggest attention is needed to achieve population‐level protection using an individual‐level SSD approach. Environ. Toxicol. Chem. © 2013 SETAC

Customer comments

No comments were found for Estimating population‐level HC5 for copper using a species sensitivity distribution approach. Be the first to comment!