Long term studies on children's health and the environment: Identifying, assessing and following up the effects of exposure to environmental factors
There is growing evidence regarding the association between the environment and children’s health and children’s greater susceptibility to environmental risk factors, particularly in utero and the first two years of life. The outcomes of environmental exposures early in life are often subtle but may have major consequences later in life, impacting health, development, productivity and quality of life. In developing countries, unhealthy environments account for a significant proportion of children’s morbidity and mortality, confounded by malnutrition and infectious diseases.
What are the Long Term Cohort Studies (LTCS) of environmental influences on children’s health?
Comprehensive studies using innovative approaches for identifying and assessing the effects of a broad range of environmental factors on children's health, covering their main developmental periods. LTCS proved, for example, the long-term effects of certain pollutants such as lead, mercury, polychlorinated biphenyls (PCBs ) and pesticides, especially dangerous for children and their developing nervous systems.
What is the feasibility of such studies?
Successful implementation of such complex and costly studies in developing countries will require innovative approaches, leading to both short-term and long-term results. In many countries, LTCS have been undertaken on nutritional, developmental and other issues, but without examining environmental risk factors. Planned or existing LTCS in North America, Europe and a number of developing countries offer unique opportunities for incorporating environmental components and for establishing collaboration. Close international cooperation is important to ensure success.
WHO pilot activities
WHO is undertaking a pilot initiative to identify on-going or planned LTCS and set up an international collaborative network including investigators from developed and developing countries. The initial activities include:
- Establishing an interest group to coordinate initial planning
- Contacting partners and donors
- Identifying the environmental components for inclusion in new or existing LTCS
- Developing and sharing core protocols.
Although LTCS in developing countries represent a challenge, they offer substantial benefits, as evidenced by success in Thailand, South Africa, Guatemala and other countries. Collateral benefits include: strengthening health care and surveillance services, transfer of technology, improving case data collection, and building and coordinating research capacity. LTCS will also enhance achievement of Millennium Development Goals (MDGs) aiming at reducing infant mortality (MDG 4) and ensuring environmental sustainability (MDG 7) and will promote healthier, cleaner and safer environments for children.
Consultation on the feasibility of long term studies on the environmental threats to the health of children in developing countries
WHO and the International Interest Group organized an informal consultation on the Feasibility of Long Term Studies (LTS) in the Environment Threats to the Health of Children in Developing Countries, October 13-15, 2003 in Montreux, Switzerland. Participants of the meeting discussed the need and feasibility of conducting LTS in developing and transition countries. They strongly endorsed the inclusion of environmental issues in LTS and the resultant "White Paper" is available here.