Declining Trends of Polychlorinated Naphthalenes in Seabird Eggs from the Canadian Arctic, 1975-2014.
There are relatively few studies of polychlorinated naphthalenes (PCNs) for biota in polar regions and even fewer reports of temporal trends. We determined concentrations of PCNs in eggs of thick-billed murres (Uria lomvia) collected from the Canadian high Arctic between 1975 and 2014 and calculated their associated toxic equivalents (TEQs). Concentrations of Σ67PCN decreased significantly in the murre eggs between 1975 and 2014 at an average annual rate of -14.9 pg g-1wet weight. Although the penta- and tetra-CNs (predominantly CN-52/60 and CN-42) dominated the PCN profile, the hexa-CNs (mainly CN-66/67) accounted for the majority of the Σ67TEQ-PCN, concentrations of which also decreased significantly between 1975 to 2014. On average, Σ67TEQ-PCN in the murre eggs accounted for only 1.9% of the total toxicity calculated for dioxin-like compounds measured in the murre eggs. As such, the TEQ-PCN concentrations calculated for the murre eggs in this study are several orders of magnitude lower than TEQ levels associated with reproductive effects in birds. This is the first published study of temporal trends of PCNs in Canadian Arctic biota.
National Wildlife Research Centre, Environment and Climate Change Canada, Carleton University , Raven Road, Ottawa, Ontario, Canada K1A 0H3.
Birgit M
0000-0001-9406-2605
BM
Braune
Aquatic Contaminants Research Division, Environment and Climate Change Canada , Burlington, Ontario, Canada L7R 4A6.
Derek C G
0000-0001-6631-9776
DC
Muir
D000818:Animals; D001110:Arctic Regions; D002170:Canada; D004784:Environmental Monitoring; D004785:Environmental Pollutants; D009281:Naphthalenes
D004785:Environmental Pollutants; D009281:Naphthalenes