Wastewater dilution index partially explains observed polybrominated diphenyl ether flame retardant concentrations in osprey eggs from Columbia River Basin, 2008–2009

Abstract

Several polybrominated biphenyl ether (PBDE) congeners were found in all 175 osprey (Pandion haliaetus) eggs collected from the Columbia River Basin between 2002 and 2009. ΣPBDE concentrations in 2008-2009 were highest in osprey eggs from the two lowest flow rivers studied; however, each river flowed through relatively large and populous metropolitan areas (Boise, Idaho and Spokane, Washington). We used the volume of Wastewater Treatment Plant (WWTP) discharge, a known source of PBDEs, as a measure of human activity at a location, and combined with river flow (both converted to millions of gallons/day) created a novel approach (an approximate Dilution Index) to relate waterborne contaminants to levels of these contaminants that reach avian eggs. This approach provided a useful understanding of the spatial osprey egg concentration patterns observed. Individual osprey egg concentrations along the Upper Willamette River co-varied with the Dilution Index, while combined egg data (geometric means) from rivers or segments of rivers showed a strong, significant relationship to the Dilution Index with one exception, the Boise River. There, we believe osprey egg concentrations were lower than expected because Boise River ospreys foraged perhaps 50-75% of the time off the river at ponds and lakes stocked with fish that contained relatively low ΣPBDE concentrations. Our limited temporal data at specific localities (2004-2009) suggests that ΣPBDE concentrations in osprey eggs peaked between 2005 and 2007, and then decreased, perhaps in response to penta- and octa-PBDE technical mixtures no longer being used in the USA after 2004. Empirical estimates of biomagnification factors (BMFs) from fish to osprey eggs were 3.76-7.52 on a wet weight (ww) basis or 4.37-11.0 lipid weight. Our earlier osprey study suggested that ΣPBDE egg concentrations >1,000 ng/g ww may reduce osprey reproductive success. Only two of the study areas sampled in 2008-2009 contained individual eggs with ΣPBDE concentrations >1,000 ng/g, and non-significant (P > 0.30) negative relationships were found between ΣPBDEs and reproductive success. Additional monitoring is required to confirm not only the apparent decline in PBDE concentrations in osprey eggs that occurred during this study, but also to better understand the relationship between PBDEs in eggs and reproductive success.

Contaminants of legacy and emerging concern in largescale suckers (Catostomus macrocheilus) and the foodweb in the lower Columbia River, Oregon and Washington, USA

“…Collection procedures were described in detail by Henny et al (2011). Egg analysis was described in detail by Gauthier et al (2008).…”

“…These chemicals inhibited osprey reproduction in terms of young produced per nest and concentrations in eggs increased rapidly, with the highest concentrations in downstream areas (Henny et al, 2009(Henny et al, , 2011. Flame retardant chemicals are widespread in the LCR and in juvenile salmon tissues, especially near urban and industrial areas (LCREP, 2007).…”

Assessing reproductive and endocrine parameters in male largescale suckers (Catostomus macrocheilus) along a contaminant gradient in the lower Columbia River, USA

“…They are similar in molecular structure to PCBs and thyroid hormones (Hu et al, 2007;Lema et al, 2008), and they adsorb tightly to the organic fraction of bioavailable suspended particulates. For osprey and other biota, waste-water treatment plants along the LCR were likely a source of PBDEs (Henny et al, 2011), which are not degraded substantially or otherwise removed by processing in such plants (Rayne and Ikonomou, 2005). Although newer alternatives for flame retardants are replacing PBDEs, the decaBDEs (such as BDE-209) are still industrially produced and, along with their metabolites, will continue to bioaccumulate (Wenning et al, 2011).…”

“…In the North Pacific Ocean, adults can bioaccumulate persistent organic pollutants which are then biotransported into freshwater by the migrating fish, their roe, and later their degrading carcasses. During the migration, organohalogens are transferred from fat to muscle (Cullon et al, 2009;Svedsen et al, 2007), which can then be consumed by foraging biota (Ewald et al, 1998) including bald eagles (Haliaeetus leucocephalus) (Buck et al, 2005), great blue herons (Ardea herodias) (Thomas and Anthony, 1999), and osprey (Pandion haliaetus) (Henny et al, 2011). Along the LCR, spatial differences exist in the concentrations of persistent organic pollutants as shown by PBDE concentrations in osprey eggs (Henny et al, 2011).…”

“…During the migration, organohalogens are transferred from fat to muscle (Cullon et al, 2009;Svedsen et al, 2007), which can then be consumed by foraging biota (Ewald et al, 1998) including bald eagles (Haliaeetus leucocephalus) (Buck et al, 2005), great blue herons (Ardea herodias) (Thomas and Anthony, 1999), and osprey (Pandion haliaetus) (Henny et al, 2011). Along the LCR, spatial differences exist in the concentrations of persistent organic pollutants as shown by PBDE concentrations in osprey eggs (Henny et al, 2011). A temporal difference was noted from 1992 to 2000, over which time total PBDE concentrations increased 12-fold in the salmonid mountain whitefish (Prosopium williamsoni), which was an order of magnitude higher than in LSS.…”