Herring gulls 2378-TeCDD

Among these was a preliminary investigation in 1980 of 2378-TeCDD in herring gull eggs, which found concentrations in eggs from Saginaw Bay,... 

As part of a detailed analysis of lake trout reproductive impairment in Lake Ontario, Cook et al. [16] determined PCDD/F concentrations in lake trout eggs from Lake Ontario, 1978-1991, which are summarized in Table 6. The concentrations are less than one-half of those in lake trout muscle from the same lake and time (Table 5). However, on a lipid weight basis, the egg to female concentration ratio of TeCDD/Fs and PnCDD/Fs was 0.6-0.7, similar to that found in herring gulls [63]. The overall trend in PCDD/F concentrations was similar to that found in lake trout muscle over the same time period, i.e., concentrations of 2378-TeCDD demonstrated the most consistent downward tendency. 

Archived samples were used to determine concentrations of 2378-TeCDD, 12378-PnCDD, 123678-HxCDD, 1234678-HpCDD, and OCDD in herring gull eggs 1981-1991 and concentrations of 2378-TeCDF, 23478-PnCDF, 123478-HxDF, and 123678-HxCDF, 1984-1991 [71]. Other congeners usually found in fish were below the detection limit most or all of the time. While there were... 

Temporal trends of 2378-TeCDD concentrations in herring gull eggs from colonies in eastern Lake Ontario over a 31 year period, 1971-2002, are shown in Fig. 14. Data for 1971-1982 are for eggs from Scotch Bonnet Island, on the west side of the Prince Edward Peninsula, and those for 1983-1993 are from Snake Island, in the Kingston, ON area [71]. Historically, concentrations of organochlorine compounds have tended to be higher in the Scotch Bonnet... 

Fig. 14 Temporal trend of concentrations (ngkg-1 wet weight) of 2378-TeCDD in pooled herring gull eggs from two colonies in eastern Lake Ontario, 1971-2002. Data for 1971— 1982 are from Hallett and Norstrom [11], for 1984-1991 from Hebert et al. [71], and for 1992-2002 from Weseloh (unpublished)...

Thus, regardless of which mathematical model best fits the 2378-TeCDD temporal trends in herring gull eggs, further analysis was not attempted. There is no reason to believe that the environmental dynamics of persistent contaminants in Lake Ontario are necessarily described by processes which are fixed over time. Loadings from point sources in the Niagara River... 

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