Scientific Frontiers in Developmental Toxicology and Risk Assessment

Excerpt

Developmental defects are a significant human-health problem. Approximately 3% of human developmental defects are attributed to exposure to toxic chemicals (e.g., lead and mercury) and physical agents (e.g., radiation), including agents found in the environment. Twenty-five percent of developmental defects might be due to a combination of genetic and environmental factors, where those factors are defined broadly to include physical, chemical, and biological agents and conditions, such as infections, nutritional deficiencies and excesses, life-style factors (e.g., alcohol), hyperthermia, ultraviolet radiation, X-rays, and the myriad of manufactured chemicals (e.g., pharmaceuticals, synthetic chemicals, solvents, pesticides, fungicides, herbicides, cosmetics, and food additives) and natural materials (e.g., plant and animal toxins and products). Because of human-health concerns about the developmental toxicity of environmental agents, scientists and regulators have focused efforts on understanding and protecting against the potential hazards of these agents to developing embryos, fetuses, and children. Recent advances in the fields of developmental biology and genomics provide opportunities to further understand the role of environmental agents in human developmental defects and, therefore, the National Research Council (NRC) undertook a project to explore the opportunities in this area.