Environmental Health

Pesticides. Drugs yes. Plastics. Fertilizers. Fuels. Synthetic fiber. Building materials. Food addictives. Detergent. The list is endless. The spoil of the twentieth –century technological revolution line our cupboards, refrigerator, and medicine cabinets, hang in our closets, cover our lawn, furnish our home, and occupy our garages. New technological and new chemical compounds –some 1,000 new compounds are developed each year in the united state alone- have been undeniable boon to humanity. They have increased food production, conquered many infectious diseases, and enabled more people than ever to enjoy “the good life. But it is becoming increasingly clear that all of this progress has a cost. The most glaring consequence is an increase in environmental pollution.

Pollution refers to any substance or energy that contributes to the development of undesirable. It includes anything that provides extra energy-in any form- leading to harmful environmental changes. For example, noise is extra energy that can cause many changes in plants and animals –including human beings.

Our bodies can cope with a certain amount of pollution, via built-in systems for self –cleansing and self renewal. The body’s repair mechanisms are constantly replacing damaged body chemicals, cell part and even whole cells. The body also has a system of chemical known as enzymes; they work –particularly in the liver – to break down or metabolize many unwanted or toxic chemical, both natural and synthetic.

These protective systems operate constantly. If the damage from toxic substances remains within the normal rate breakdown and replacement, it will not usually have a harmful effect on the individual. We say that the person’s exposure is below the effect’s threshold.
If the exposure exceeds the threshold, however, the rate at which the individual’s body is damaged will exceed the rate at which it can repair itself , and the individual may suffer a loss of body function that may lead to a permanent disability.

Experts agree as to weather this threshold concept applies to cancer – causing chemical, or whether a single molecule of certain chemicals is sometimes sufficient to cause the disease.