About the Study


Our social environment is changing rapidly. In Japan and overseas, people are increasingly concerned about the impact of hazardous chemical substances in the environment. Of particular importance are the many substances which negatively influence children's health.

Children's environmental health has long been high on the international agenda. In 1997, the Miami Declaration on Children's Environmental Health was agreed upon by the G8 Environment Ministers` Meeting. The same group agreed on international cooperation in epidemiological studies when they met in Siracusa, Italy in 2009. The JECS is aimed to protect children's health by contributing to the safe management of chemicals and environmental pollution prevention.


The major aim of this study is to identify harmful factors in the environment affecting children's growth and health, and to investigate the relationship between such factors and children's health condition. On the basis of the results of this study, the Japanese government will make regulations and take measures to control the use of harmful materials which have undesirable effects on children's health. The final aim of this study and government action is to build a secure environment; where children can grow up healthy and parents can raise children with confidence in the safety of their environment.

Study Overview

The Japan Environment and Children's Study started in January 2011. The recruitment of hundred thousand pregnant women was achieved in March 2014. Follow-up research of the participating children's health condition and environment will continue for 13 years. The study is scheduled to conclude in 2032, including the period for data analysis.

Follow-up programs periodically examine children's health condition, beginning at the early stage of pregnancy until the participating child reaches the age of 13. In total, 100,000 children and their parents take part in this study across fifteen regions of the nation. It is the first time in Japan to conduct such a nation-wide and long-term birth cohort study about children's health and environment.

Study Documents

This page shows the related documents of the JECS.

JECS Study Protocol (Version 1.4) PDF download
[PDF: 890KB]
JECS Sub Cohort Study Protocol (Version 1.01) PDF download
[PDF: 798KB]
Statistics for Children's Health and Environment PDF download
Not available in English now

(new window : You are going to the other sites.)