Global Effects of Solvent Usage

There are critical needs with regard to protecting the environment (Medina, 1996). The use of solvents introduces stresses on ecosystems, ultimately on the global level. More testing for acute human toxicity is needed, but increasingly, researchers will strive to include effects on entire ecosystems, and long-term, multigenerational effects on fertility, reproductive quality, and hormonal functions. Any solvent that leads to environmental problems, that can be persistent, toxic, and bioaccumulative, or any combination of these three attributes, needs to be evaluated (Division, 1996). This 

However, there is a need for better tests to assess ecological damage potentially caused by single-compound chemicals, the byproducts of various waste treatment processes, and the degradation products of intentional processes or unintentional process emissions that find their way into the environment. 

The last 50 years have seen the introduction of many new chemicals. Many have stood the test of time and shown their benefits to outweigh their environmental risks. For some, however, important adverse environmental effects emerged. The search to replace those without further environmental effects has become a strong driving force in industry, in the scientific community, and in the general public. 

Some of the surprise effects of chemicals have been due to a failure to predict the scale on which technologies might be used once they were shown to be beneficial when used on a limited scale. For example, DDT has side effects that have increased nonlinearly with the scale of application as a result, the incremental benefits of a seemingly benign technology reversed when it was applied on a larger scale (the problem of MTBE was discussed earlier in this chapter). New technologies have to be constantly reevaluated in anticipation of scale effects. 

New adverse environmental impacts will continue to be found, even with some of the substitutes. In some cases, biodegradable substitutes might be possible. The search for alternative pesticides or other products that have less adverse environmental impact has been rewarding to society and industry. Such efforts need to be continued and will be driven by the marketplace s responding to public and government interests. 

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