35 lines
5.1 KiB
Markdown
35 lines
5.1 KiB
Markdown
---
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title: "Biomarker"
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chunk: 3/3
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source: "https://en.wikipedia.org/wiki/Biomarker"
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category: "reference"
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tags: "science, encyclopedia"
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date_saved: "2026-05-05T07:15:13.536230+00:00"
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instance: "kb-cron"
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---
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Biomarkers are being used to identify the effects of water contamination on aquatic organisms. Benthic macro-invertebrates reside in the sediment on the bottoms of streams, which is where many contaminants settle. These organisms have high exposure to the contamination, which makes them good study species when detecting pollutant concentrations and pollution impacts on an ecosystem. There are a variety of biomarkers within an aquatic organism that can be measured, depending on the contaminant or the response in question. There are also a variety of contaminants within water bodies. To analyze the impact of a pollutant on an organism, the biomarker must respond to a specific contaminant within a specific time frame or at a certain concentration. The biomarkers used to detect pollution in aquatic organisms can be enzymatic or non-enzymatic.
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Rachel Carson, the author of Silent Spring, raised the issue of using organochlorine pesticides and discussed the possible negative effects that said pesticides have on living organisms. Her book raised ethical issues against chemical corporations that were controlling the general reception of the effect of pesticides on the environment, which pioneered the need for ecotoxicological studies. Ecotoxicologial studies could be considered the precursors to biomarker studies. Biomarkers are used to indicate an exposure to or the effect of xenobiotics which are present in the environment and in organisms. The biomarker may be an external substance itself (e.g. asbestos particles or NNK from tobacco), or a variant of the external substance processed by the body (a metabolite) that usually can be quantified.
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== History ==
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The widespread use of the term "biomarker" dates back to as early as 1980. The manner in which the environment was monitored and studied near the end of the 1980s was still mainly reliant on the study of chemical substances that were considered dangerous or toxic when found in moderate concentrations in water, sediments, and aquatic organisms. The methods used to identify these chemical compounds were chromatography, spectrophotometry, electrochemistry, and radiochemistry. Although these methods were successful in elucidating the chemical makeup and concentrations present in the environment of the contaminants and the compounds in question, the tests did not provide data that was informative on the impact of a certain pollutant or chemical on a living organism or ecosystem. It was proposed that characterizing biomarkers could create a warning system to check in on the well being of a population or an ecosystem before a pollutant or compound could wreak havoc on the system. Now, due to the development of biomarker studies, biomarkers can be used and applied in the fields of human medicine and in the detection of diseases.
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=== Definition ===
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The term "biological marker" was introduced in 1950s.
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In 1987, biological markers were defined as "indicators signaling events in biological systems or samples" that could be classified into three categories: exposure, effect and susceptibility markers.
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In 1990, McCarthy and Shugart defined biomarkers as, "measurements at the molecular, biochemical, or cellular level in either wild populations from contaminated habitats or in organisms experimentally exposed to pollutants that indicate that the organism has been exposed to toxic chemicals, and the magnitude of the organism's response".
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In 1994, Depledge defined a biomarker as, "a biochemical, cellular, physiological or behavioral change which can be measured in body tissues or fluids or at the level of the whole organism that reveals the exposure at/or the effects of one or more chemical pollutants."
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In 1996, Van Gestel and Van Brummelen attempted to redefine biomarkers to unambiguously differentiate a biomarker from a bioindicator. According to Van Gestel and Van Brummelen, a biomarker by definition should be used only to describe sublethal biochemical changes resulting from individual exposure to xenobiotics.
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In 1998, the National Institutes of Health Biomarkers Definitions Working Group defined a biomarker as "a characteristic that is objectively measured and evaluated as an indicator of normal biological processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention."
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In 2000, De Lafontaine defined the term biomarker as a "biochemical and/or physiological change(s) in organisms exposed to contaminants, and thus represent initial responses to environmental perturbation and contamination".
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== Active biomonitoring ==
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De Kock and Kramer developed the concept of active biomonitoring in 1994. Active biomonitoring is a comparison of the chemical/biological properties of a sample that has been relocated to a new environment that contains different conditions than its original environment.
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== See also ==
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== References ==
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== External links ==
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BiomarkerKB, an open-access knowledge base that integrates and organizes biomarker data from multiple public sources, George Washington University, 2025 |