This core will essentially focus on research developing relevant test systems for assessing EDCs and other pollutants of concern (pharmaceuticals, nanoparticles). The Idea Company in Japan will lead on developing the partial life cycle test using Xenopus tropicalis and other OECD relevant systems for amphibians, supported by UK participants. It is proposed that the stickleback OECD ring test will comprise part of this theme. This will include knowledge transfer to Japan to support rearing practices for the stickleback. It is also envisaged that within this core, there will be work to investigate and develop short OECD test systems using fish embryos. This core will also consider the possibility of including some invertebrate testing systems, depending on the investigators brought to this core theme.