May the followings be helpful.

1. Chen, D.; Hale, R. C., A global review of polybrominated diphenyl ether flame retardant contamination in birds. Environment International 2010, 36, (7), 800-811.

2. Park, J. S. et al., Time-trends and congener profiles of PBDEs and PCBs in California Peregrine falcons (Falco peregrinus). Environmental Science & Technology 2009, 43, (23), 8744-8751.

and u could search for the papers written by the experts on this field, eg. covaci, letcher, etc.

Thanks, I have the first paper already! I haven't seen the second, but i'll get it. I really would like OC pesticides data (DDT & metabolites in particular). Thanks for the help!

check this paper, not sure if you'll find the temporal element or not.  Also check papers by Pierre Mineau.  And Wim Mullie has a number of papers on this subject from Africa, again I'm not sure about the temporal element.

Bouwman,H.,etal.,Halogenatedpollutantsinterrestrialandaquaticbirdeggs:Convergingpatternsof

pollutant profiles, andimpactsandrisksfromhighlevels.Environ.Res.(2013), http://dx.doi.org/10.1016/j.envres.2013.06.003i

EnvironmentalResearch ∎ (∎∎∎∎) ∎∎∎–∎∎∎

I am uncertain if this is possible, as I am not a chemist, however my children and now myself have had a reoccuring MRSA infection and it came from Coombabah in Queensland where they spray pesticides/insecticides to control mosquito larva.  Id be happy for you to look into this and to ask me any questions.

Kindest regards,

Julie Lawson.

Haven't read it, and I think this is not what you want, but maybe comparing the temporal trends you found for PCBs with the ones for PBDEs could be also interesting, since PBDEs "followed" PCBs:

Miller, A et al. (2015) Brominated flame retardant trends in aquatic birds from the Salish Sea region of the west coast of North America, including a mini-review of recent trends in marine and estuarine birds.