Abstract: There can be no question in anyone's mind that our ability to analyze the structure and composition of materials in all media has grown in amazingly exponential ways in the last several decades. Our detection limits have gone from micrograms to the subpicogram level. A millimeter-sized sample presented a challenge in 1950; but today we look at submicron units, in fact, at single atoms resolved in analytical electron microscopes in an almost routine manner. Analysis time has changed from hours or sometimes even days for a complete qualitative and quantitative analysis on a sample to modern capabilities which include real-time spectroscopy on in situ experiments which give us data on molecular dynamics in the femtosecond time regime. Trace analysis, the detection and determination of impossibly tiny quantities of elements and molecules in increasingly complex matrices, is readily accomplished today. These are exactly the types of samples usually involved in environmental analysis. Yet, there is a tendency among some groups to view analytical advances as a negative factor in environmental studies because the ability to measure extremely small quantities can focus regulators on placing restrictions on materials not previously detectable. If so, that is a rare instance where increased knowledge can be considered a setback.!22
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