Monitoring biomarker

L. Ball, A. Jones, P. Boogaard, W. Will, and P. Aston, Development of a competitive immunoassay for the determination of N-(2-hydroxypropyl)valine adducts in human haemoglobin and its application in biological monitoring. Biomarkers 10, 127-137 (2005). 

There is no clinical disease state unique to heptachlor. A major problem in developing a biomarker of effect for heptachlor or heptachlor epoxide is that human exposures to these compounds have occurred concomitantly with exposures to other chemicals, and it is difficult to attribute the health effects to heptachlor or heptachlor epoxide alone. More data that quantify the biological effects as well as data that distinguish heptachlor and heptachlor epoxide exposures from those of other chemicals would be useful for developing biomarkers of effect for population monitoring. Biomarkers that could indicate the length of time since exposure would also be useful. 

The residues and metabolites of a substance can be measured in an organism or an environmental medium. Alternatively, biological effects known as biomarkers that are known to be the result of exposure to a hazard can be used to determine exposure levels [131]. In some cases, monitoring biomarkers in employees (e.g., metabolites in urine) can prove cheaper than measuring airborne concentrations of a substance in the workplace [132],... 

Case Study 2 Drug Candidate-Induced Micro vascular Injury at the Exocrine-Endocrine Interface in the Rat with Unsuccessful Confirmation of Toxicity In Vitro and No Pancreas-Specific Monitorable Biomarkers Identified... 

Biomarkers for internal close of the intoxicant—dose monitoring. Bioniarkers for early biological changes following exposure— effect... 

Acid- and alkaline phosphatases act on a variety of mono- and multiple phosphate carrying low molecular mass molecules. In addition, they hydrolyze many, but not all, phosphoproteins. They are in use for decades to easily screen for diseases, however, somewhat unspe-cifially. For instance, acid phosphatase is used as biomarker for prostate cancer, and alkaline phosphatase to monitor bone (de-) mineralization and liver tumors. 

The purpose of this chapter is to describe the analytical methods that are available for detecting, measuring, and/or monitoring methyl parathion, its metabolites, and other biomarkers of exposure and effect to methyl parathion. The intent is not to provide an exhaustive list of analytical methods. Rather, the intention is to identify well-established methods that are used as the standard methods of analysis. Many of the analytical methods used for environmental samples are the methods approved by federal agencies and organizations such as EPA and the National Institute for Occupational Safety and Health (NIOSH). Other methods presented in this chapter are those that are approved by groups such as the Association of Official Analytical Chemists (AOAC) and the American Public Health Association (APHA). Additionally, analytical methods are included that modify previously used methods to obtain lower detection limits and/or to improve accuracy and precision. 

The concept of biomarkers is illustrated in Figure 4.4. As the dose of a chemical increases, the organism moves from a state of homeostasis to a state of stress. With further increases in dose, the organism enters first the state of reversible disease, and eventually the state of irreversible disease, which will lead to death. In concept, all of these stages can be monitored by biomarker assays (lower part of conceptual diagram). 

Some biomarker responses provide evidence only of exposure and do not give any reliable measure of toxic effect. Other biomarkers, however, provide a measure of toxic effects, and these will be referred to as mechanistic biomarkers. Ideally, biomarker assays of this latter type monitor the primary interaction between a chemical and its site of action. However, other biomarkers operating down stream from the original toxic lesion also provide a measure of toxic action (see Figure 14.3 in Chapter 14), as, for instance, in the case of changes in the transmission of action potential... 

Thns far, the discussion has dealt primarily with biomarker responses in living organisms. In the next section, consideration will be given to the exploitation of this principle in the development of bioassay systems that can be nsed in environmental monitoring and environmental risk assessment. 

In a similar way, an integrated biomarker approach has a role when carrying out experiments in mesocosms. Under these controlled conditions, behavioral effects of neurotoxic pollutants, acting singly or in combination, can be monitored and compared with data on predator-prey relationships and effects at the population level. The employment of mechanistic biomarker assays can facilitate comparisons between results obtained in mesocosms and other data obtained in the field or in laboratory tests. Here is one way of attempting to answer the difficult question— how comparable are mesocosms to the real world ... 

Peakall, D.B. and Fairbrother, A. (1998). Biomarkers for monitoring and measuring effects. In P.E.T. Douben (Ed.) Pollution Risk Assessment and Management. Chichester, U.K. John Wiley 351-356. 

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