Chemicals and pharmaceutics are indispensable in modern daily life. Correct safety evaluation of chemicals is essential to protect users. The use of experimental animals in chemical safety evaluation is under pressure, not only because of ethical reasons, but also because these tests are expensive, time consuming, low in throughput and often give unsatisfactory predictions of human toxicity. For these reasons, we have limited toxicological knowledge of many chemicals. Our modern mechanistic CALUX® bioassays provide insight in the modes of action of toxicants and can be used as alternative methods to assess chemical safety, particularly when coupled to so-called adverse outcome pathways. These methods are particularly suited for use in integrated testing and read across procedures as described by ECHA and OECD.