Bioindicator techniques

Nowadays, Microtox is the most popular bioassay available that uses bioluminescent bacteria as its active element. Analysts find it a useful tool for assessing pollution in different compartments of the environment, possessing as it does both the advantages of bioindicator techniques and the precision of classic instrumental analysis. Here are some examples of its application ... 

One of the most widely studied chemotaxonomic characters in insects has been cutic-ular hydrocarbons (CHCs). The earliest descriptive papers on CHCs were by Jackson (1970), Jackson and Bayer (1970), Jackson and Blomquist (1976), Lockey (1976), and Lange et al. (1989). Carlson and collaborators (Carlson and Service 1979, 1980 Carlson et al., 1978 Carlson, 1988) were the first to recognize the special role of CHCs in chemical taxonomy. Since then, numerous reviews have devoted sections to CHCs (Lockey, 1980, 1988 Howard and Blomquist, 1982,2005 Blomquist and Dillwith, 1985 Blomquist et al., 1987 Kaib et al., 1991 Singer, 1998 Howard, 1993). Since the introduction of molecular techniques, the number of insect chemotaxonomy papers about hydrocarbons has dropped, but there are still many submissions and publications. Explanations for this continued interest in insect CHCs include not only their importance as chemical cues in recognition processes, but also the fact that insects are excellent bioindicators of nature conservation, and inversely, pests to control. 

As noted above, sophisticated techniques are available for the analysis of mutations at the gene and chromosomal level. Such analysis can be used to define the mechanisms of formation of specific human tumors. In addition, it can be used for the development of informative bioindicators of a tumor response. These include ligation-based PCR technique and fluorescence in situ hybridization (FISH) that can be used in conjunction with clones that cover limited genomic regions to identify specific chromosomal breakpoints (Preston, 2005a). 

Recent advances in knowledge of the underlying mechanisms of carcinogenesis and the ever-increasing portfolio of whole genome molecular assay techniques have made it much more feasible to identify and select informative bioindicators of disease processes, especially cancer (Block et al. 2008 Coitfad et al. 2008 Preston 2005). 

The use of some other techniques, including electrodialysis, diffusion through membrane, diffusive gradient in thin-film (DGT) (Hooda et al. 2001), and bioindication has also been proposed. However,... 

The strong similarity in terms between instrumental chemical analysis (qualitative and quantitative measurements) and the field of bioindicators (as a qualitative approach to pollution control) and biomonitors (as a quantitative approach) makes it worthwhile to compare the two techniques. 

In actual "damage to forest" ("acid rain"- probiems) investigations, the main matrices which must be anaiyzed are needles, leaves, pieces of wood, roots and soil. The elements Al, B, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, S, Sr, Ti, V, and Zn can be determined routinely in such samples by ICP/DCP-spectrometry (Table 9). The concentrations of the heavy metals Cd, Pb, Hg, As and others are in most cases too low (exception soil, for these analytical techniques). A similar picture can be obtained for the field of bioindicators for environmental influences (plants, animals, organs of man) (Schramel et al., 1984 Wolf et al., 1984) (Table 10). In case of soils and sludges, in most the samples one can obtain all relevant elements, such as the legally regulated heavy metals Cd, Pb, Zn, Cu, Ni, and Cr (Table 11,12) (Schramel et al., 1982). 

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