Environmental investigation, questions

Another question which is rarely discussed is the variety of determined elements. Generally it seems that the type of determined elements depends more on the method used in the investigation than on the real need of determination. Elements such as Pb, Cd, Zn, Cu are among the very important pollutants but they are also easily determined by atomic absorption spectrometry (AAS), a very popular method. Therefore a considerable number (if not the majority) of environmental investigations deal with these elements only. The elements that remain outside the scope of popular analytical techniques are actually those that still have unknown functions in the organisms, and the necessity of their determination came forward quite recently. A good example in this respect are rare earth elements and platinum metals in plants. 

Sodium nitroprusside was first prepared and investigated in the middle of the nineteenth century, and a comprehensive summary of the earlier chemical investigations has been published (17). Up to 1910-1930, the addition reactions of bases to NP were explored, involving the characterization of colored intermediates (e.g., with SH-, SR-, and SO3 ), useful for analytical purposes. The hypotensive action of NP was first demonstrated in 1929, and a considerable research effort has attempted to establish the mode of action of NP and its metabolic fate. Questions still arise on the mechanism of NO release from NP in the biological fluids, and we refer to them below. New accounts dealing with modern structural and reactivity issues associated with the coordination of nitrosyl in NP and other complexes have appeared (18-20). From the bioinorganic and environmental viewpoint, nitrosyl iron complexes have been studied with... 

Systemic changes were investigated quantitatively via questions about environmental affairs groups in the firms. About 65X of interviewed firms had such groups. Although the primary purpose of environmental affairs units appears to be to aid the direct compliance effort, their new capabilities may have important long-term implications for the pattern of innovation in the primary lines of business. ... 

A further problem concerning the sampling location must be discussed. Many environmental queries include the question of the depth at which the sample must be taken. For example, it is of essential importance to know the depth or, better, the depth interval in the studies of soil, river, or groundwater pollution. The sampling depth must be adapted to the specific purpose of the investigation. Often this aim depends on the planned use of the soil area or water body. 

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