Virtually all diseases have an environmental component. Environmental health science is the study of how the environment affects human health. The environment includes exposure to such things as sunlight, pesticides, pharmaceuticals, tobacco smoke, and other chemicals in the environment or workplace.
Positive exposures count, too, such as essential vitamins and nutrients in our diet.
The second element of health is genetics, which refers to a person s individual genetic susceptibility to diseases. For example, a woman carrying the breast cancer gene has a higher likelihood of developing the disease compared to a woman who does not have the gene. Time, or age, is the third interactive element. Our susceptibility to environmental exposures changes over time as seen by the greater susceptibility of the very young and the very old to diseases. Of the three elements contributing to health, environment is the only one that is reasonably within our control, thus it is critical that we develop a better understanding of the environmental components of health and disease.