1. Ecotoxicology

   • David B. Peakall
   • Lee R. Shugart

   Editorial Pages: 1 - 1

2. The threshold problem in ecotoxicology

   • John Cairns Jr

   Papers Pages: 3 - 16

3. Effects of DDT treatments applied for tsetse fly control on White-headed Black Chat (Thamnolaea arnoti) populations in Zimbabwe. Part I: population changes

   • R. J. Douthwaite

   Papers Pages: 17 - 30

4. Mortality from the pesticides aldrin and dieldrin in British Sparrowhawks and Kestrels

   • I. Newton
   • I. Wyllie
   • A. Asher

   Papers Pages: 31 - 44

5. Sequential expression of biomarkers in Bluegill Sunfish exposed to contaminated sediment

   • C. W. Theodorakis
   • S. J. D'surney
   • L. R. Shugart

   Papers Pages: 45 - 73

6. A selection of forthcoming papers

   Announcement Pages: 75 - 75