We humans live our lives interacting with our environment every day. Humans are the part of the ecosystem with the other creatures, and we all live in the midst of the rapid and global environmental changes. The Ministry of the Environment launched the “Japan Environment and Children’s study (JECS)” nationwide in January 2011. Its mission is to determine the effects of environmental factors on child health. Specifically, the study examines children’s exposure to chemicals (from the fetal to childhood stages) and living conditions so as to reveal the environmental factors’ effects on their health, and its research finding is to inform the creation of an appropriate risk management system against chemicals, et