The substitution of animal testing of chemicals by non-animal testing prediction systems (NATPS) could lead to large-scale misuse of these systems, the new PAN Europe report "AOP, the trojan horse for industry lobby tools?" warns. The still immature NATPS were originally intended for chemicals in cosmetics where animal testing is banned.
However, examples show that their use is extended to other chemical groups such as pesticides, not to predict toxicity but in stead to disqualify the outcome of animal testing. Observed liver and thyroid tumours in animal testing are already overruled by predictions about possible differences in mechanisms of action and considered irrelevant; DG SANTE even allows industry to overrule OECD-guided experimental testing on endocrine disruption by these prediction systems. While use of NATPS-systems is a step forward in case of screening of chemicals that miss toxicity data, use to overrule the outcome of animal testing was never the intention and should be prohibited.
An invited-only network of government (EU-JRC, US-EPA) and industry experts that are promotors of NATPS is closely cooperating to develop these prediction systems. Industry lobby groups have been campaigning for many years to adopt such systems and tools. The new systems will increase profit of industry since expensive animal testing won't be needed anymore. Now, more than 50 million Euro's of taxpayers money is spent in EU-funded programs for the main NATPS-tool called AOP, the Adverse Outcome Pathway. NGO's except animal wellfare groups are excluded from this close cooperation. By subsequently adopting these AOP's at OECD-level, a certain status is given to very immature systems.
AOP is a US-style predictive system with an unknown level of predictability. AOP is based on information about certain elements of chemical action in the body like a "mechanism of action" and/or "key events. These elements, however, only show a glimpse of reality of the whole spectrum of what actually happens when a chemical enters the body, several organs are involved, communication systems are reacting with feedback mechanisms, transcription of genes and protein synthesis. Even after decades of research the precise mechanisms by which smoking causes lung cancer, DDT causes egg-shell thinning, or TBT causes imposex are still a matter of debate. AOP gives some insight but cannot be seen as a reliable prediction tool at the moment, certainly not when human bodies are exposed to dozens of chemicals per day at the same time.
Hans Muilerman of PAN Europe states: ’Non -animal testing systems like AOP are still in their infancy; for the moment their use is only helpful to get an indication of the risks of specific chemicals for which toxicity data is missing. Use for chemicals with available toxicity data, like pesticides, to overrule the outcome of animal testing, is a complete misuse of the AOP-tool and should not be allowed in EU risk assessment'.
