Possible effect of lead on egg-shell thickness in kestrels 1874-1974.
D000818:Animals; D001717:Birds / Q000502:physiology*; D003718:Denmark; D004528:Egg Shell / Q000032:analysis; D006843:Hydrocarbons, Chlorinated / Q000032:analysis; D007854:Lead / Q000032:analysis / Q000494:pharmacology*; D012424:Rural Population; D013997:Time Factors; D014505:Urban Population
D006843:Hydrocarbons, Chlorinated; D007854:Lead