Environmental Exposures Essay

1. Discuss why linking environmental exposure to disease is difficult.

As discussed by Stanhope and Lancaster (2010), the study of environmental epidemiology is difficult because of the complexity of the relationships between host, agent, and environment. These three elements form the classic epidemiologic triangle. (p. 89) Additionally, these conceptual elements of the triangle can themselves be complex.

The host “may refer to a community spanning different ages, genders, ethnicities, cultures, and disease states.” (P.89) What effects are seen from the exposure of a host to an agent is dependent on many factors.

Some examples of this variability in the host-agent interaction include pregnant women, and COPD sufferers.

The fetuses of pregnant women are more susceptible to the damaging effects of exposure to mercury than are an adult male. And a COPD patient is more susceptible to the effects of an elevated level of ozone, than is an individual with healthy lungs.

Environmental factors are probably the most complex of the three legs of the epidemiologic triangle. Before the agent can reach the host, it has to exist in and pass through the ambient environment.

Few agent are unaffected by the environment. Air and wind can dilute or concentrate agents. Sunlight can break them down, as in the case of some bacteria, or increase their levels, as in the case of ozone.

And finally, as stated by Stanhope and Lancaster (2010), the usefulness of epidemiologic studies is sometimes limited by the quality of the cause and effect data available. “Studies are usually performed on healthy adults whose biological systems are quite different from those of neonates, pregnant women, children, the immunosuppressed, and older adults. (p. 89)

Reference:

Stanhope, M. Lancaster, J. (2010). Foundations of nursing in the community:

Community