Levels of serum POP related xenobiotic induced transactivities of breast cancer cases and controls. A) serum xenobiotic agonistic induced ER and AR receptor transactivity; B) serum xenobiotic induced AhR transactivity (see legend to Table 3). % agonistic XER and XAR indicate a significant increase for the XER and XAR transactivity compared to the the solvent control. AhR-TEQ: AhR-TCDD equivalent. *: significant differences between cases and controls.