Ecological Effects Related to TEQs for 2,3,7,8-TCDD

TEQ Values Eound in Eield Studies, and Ecological Effects Associated with Them 

Egg mortalities of 8-39% correlated well with TEQ values Relationship to continued poor breeding success Related to embryonic mortality 

PCB fraction accounted for 75%+ of TEQ by either assay reduced productivity of birds in this area TEQs mainly due to PCBs, especially 3,3, 4,4 -TCB Reduced reproductive success, but less effect than expected from high TEQs PCDDs, PCDFs, and PCBs made variable, but on the whole similar contributions to TEQ values probably not high enough to adversely affect fish populations TCDD mainly 2,3,7,8-TCDD Reduced hatching 

The results for tree swallows (Tachycineta bicolor) in the area of the Upper Hudson River are surprising because the birds were still able to breed with TEQs far above the levels that had severe/fatal effects on other species of birds. However, there 

Organic Pollutants An Ecotoxicological Perspective, Second Edition 

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