Until populations stabilize growth pressures will force man into relatively undeveloped environments. Such invasion involves tampering with the landscape and disturbing the habitats of the flora and fauna. It is generally recognized that population pressures and the many needs of society require urban expansion, the founding of new communities and the occupation of isolated site for the development of needed resources. It is also recognized, however, that irresponsible development has resulted in severe environmental degradation and a steadily declining quality of life for many people.
Many environmentalists recognize that compromise is necessary. Environmentalist provide a valuable service by exerting pressure to ensure that the environment is not needlessly damaged and that wherever feasible it is restored to as near its original condition as possible.
Pollution and Contamination
Pollution and contamination seem to be synonymous but they are not strictly the same. A contaminated water is also a polluted water, but a polluted water is not always contaminated. That is, water can be polluted without being contaminated.
Pollution is the fouling of the environment by natural phenomena or human activities. Pollution need not involve constituents hazardous to health. They may merely be offensive to sight, taste or smell. Pollution connotes a certain concentration of impurity relative to the intended uses of land, water or air of the degree of fouling that constitutes pollution.
Contamination is pollution involving constituent that are hazardous to health because of their nature or quantity. Water may be considered polluted if it is contaminated or if it contains substances that are offensive to the senses or detrimental to its usefulness. An example of contamination is the presence of iron which stains laundry and leaves a scale in hot water heaters. in a nutshell, A contaminated water is a polluted water, but a polluted water is not always contaminated.
Contamination is simply the presence of a substance where it should not be or at concentrations above background. Pollution is contamination that results in or can result in adverse biological effects to resident communities. All pollutants are contaminants, but not all contaminants are pollutants. Differentiating pollution from contamination cannot be done solely on the basis of chemical analyses because such analyses provide no information on bioavailability or on toxicity.
Effects-based measures such as laboratory or field toxicity tests and measures of the status of resident, exposed communities provide key information, but cannot be used independently to determine pollution status. Laboratory studies can be predictive, but are rarely realistic. Measures of resident communities include innate natural variability and cannot easily distinguish between adaptation to contamination (a genetic process) and acclimation (a physiological process that may
decrease energy reserves, possibly reducing such critical population-level parameters as
Finally, contaminant effects may not only be direct but also indirect; predicting such effects requires knowledge of the system under study as well as appropriate use of lines of evidence