In order to make an overall ranking of the hazard of the samples a simple ranking scheme was applied. For each toxicity test, samples considered not toxic using the criteria stated above have been classified as negative. The toxic samples were then ranked from the most toxic sample (number 1) to the least toxic samples in each test method. In the H4IIE-luc bioassay a sample for which a bio-TEQ based EC20 could not be determined has been considered negative. Samples for which an EC20 based bio-TEQ can be determined have been ranked from the sample with the highest dioxin-like activity to the sample with the lowest dioxin-like activity.