Bioindicators and Biomarkers
The health of an ecosystem can be examined through the use of bioindicators (BI), while the health of a human being can be determined using some molecules such as biomarkers (BM). BI are complete organisms or part of them that can be measured to detect changes in the environment, the presence of pollution and its effect on the ecosystem, as well as the observation of the progress of environmental clean-up. On the other hand, specific kinds of BI are the BM, which are biomolecules, secondary metabolites or measurable parameters used in medical research and practice to provide an insight into the mechanics and course of a disease. In general BM are classified into three groups: exposure, effects or susceptibility, and their role depends on the sensitivity, specificity, reliability and reproducibility of the methods used in the determination of the target molecule selected to be an specific BM, and it has to be validated under the development of guidelines, supported with good laboratory practice, epidemiological studies and clinical trials. BM can be used to detect subclinical stages, to become a diagnostic tool, to observe the efficacy of the treatment or monitoring the different stages on the development of the pathology.