Validation of Ontario's new laboratory‐based bioaccumulation methods with in situ field data

Abstract

Abstract-To validate the standardization of a laboratory protocol for measuring bioaccumulation, laboratory-derived tissue residues and biota-sediment accumulation factors (BSAFs) were compared with historical field data from nine sites in Ontario, Canada. As a result of temporal discontinuity between the field and the laboratory studies, a priori considerations, such as changes in site conditions or concentrations of contaminants in sediment, were necessary to assess whether to compare absolute or relative measures of bioaccumulation. For the majority of sites, BSAFs for field-collected and laboratory-exposed fish were within a factor of 2. Biotasediment accumulation factors for laboratory-exposed oligochaetes were typically greater than those for mussels caged in the field, by a factor of 2 to 9. Overall, the laboratory methods for all species generally overestimated the relative bioavailability of contaminants compared with field conditions by a factor of 1.1 to 9.2. Other than the great disparity observed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) between field and laboratory studies, on average the laboratory-derived BSAFs with Pimephales promelas and Lumbriculus variegatus overestimated those from field-collected fish and field-exposed mussels by factors of 1.6 and 3.6, respectively. The laboratory method reflects a potentially worst-case exposure scenario and provides an appropriately conservative estimate of bioaccumulation. Laboratory-based estimates can be comparable to bioaccumulation data from the field but may be confounded by species-specific differences in routes of exposure and bioaccumulation of certain compounds or other environmental and biological factors that should be considered in these comparisons. Environ. Toxicol. Chem. 2011;30:950-958. # 2011 SETAC

Assessing metal bioaccumulation from estuarine sediments: comparative experimental results for the polychaete Arenicola marina

“…Differences in bioaccumulated metal concentrations between laboratory-and field-collected worms may be attributable not only to test duration but also to changes in sediment composition, differences in temperature affecting metabolic rates and differences in the organisms' behaviour (Van Geest et al 2011). Differences associated with changes in sediment concentrations among samplings have been considered here through the development of BSAFs, but this factor is only responsible for minor differences (for example, Cu bioaccumulation for the Gannel sediments and Ag for the Thames sediments).…”

“…Direct measurements of bioaccumulated metal concentrations account for physiological differences between sediment-affected organisms and take into account geochemical factors (De Jonge et al 2009;Van Geest et al 2011). While field studies offer information on real environmental situations, bioaccumulation bioassays are useful to obtain direct measurements for assessment of hypothetical situations or when the habitat under study is otherwise (to be) altered, for example by dredging activities, and obtaining field-collected tissue is not possible (Van Geest et al 2011). In addition to standardisation of protocols, field validation of bioaccumulation tests is needed if quantitative estimates of exposure are to be used with confidence in ecological risk assessment and decision-making (ASTM 2010;Van Geest et al 2010).…”

Letter to the Editor

“…The Ontario Ministry of the Environment sediment bioaccumulation method has been developed as a standard method [26,27] and reviewed by an international panel of sediment toxicology experts. It was validated with 12 fieldcollected sediments contaminated with various compounds (polychlorinated biphenyls [PCBs], dioxin-like PCBs, dioxins and furans, perfluoro-compounds, polycyclic aromatic hydrocarbons, arsenic, and pesticides) [26,28]. An international, interlaboratory study of this method by laboratories in Canada and the United States was coordinated by the Ministry of the Environment and Climate Change in spring 2014.…”

Interlaboratory evaluation of the assessment of arsenic bioaccumulation from field collected sediments using Hexagenia spp

“…To address this need, a bioaccumulation test method that built on the existing standard L. variegatus method was developed at the Ontario Ministry of the Environment and Climate Change (MOECC) [5][6][7]. This bioaccumulation method [7] has been reviewed by an international panel of sediment toxicology experts.…”

“…This bioaccumulation method has been reviewed by an international panel of sediment toxicology experts. Internal validation of the method with 3 freshwater species included the side‐by‐side assessment of accumulation from 12 field‐collected sediments contaminated with various compounds (polychlorinated biphenyls [PCBs], dioxin‐like PCBs, dioxins and furans, perfluoro‐compounds, polycyclic aromatic hydrocarbons [PAHs], arsenic, and pesticides), interanalyst comparisons of accumulation, comparison of results on repeated tests with the same sediment samples, and comparison of laboratory with field‐based results . Sediment bioaccumulation studies using the MOECC method with L. variegatus , Hexagenia spp., and Pimephales promelas (fathead minnows) identified species‐specific differences in which tissue concentrations vary with contaminant and sediment type .…”