Table 4. Relative estrogenic potential of chemicals sampled by polar organic chemical integrative samplers (POCIS) at three sites in the McKenzie River basin, Oregon, September–October 2007.

[A and B are replicate samples. EEQ, estimated estradiol equivalents as determined by the yeast estrogen screen; ng/L, estimated nanograms of 17β-estradiol per liter of water which gives an equivalent response; ND, not determined - value was less than the 99-percent confidence interval of the negative (solvent) controls; detections are highlighted as bold type in shaded cells]