Endocrine disruption biomarkers

Another potential histopathological biomarker of endocrine disruption is the development of ovotestes in the lobster Homarus americanusf... 

Develop biomarkers of endocrine disruption. F iirther evidence of endocrine disruption is required in addition to population parameters. Biochemical and histopathological biomarkers are required to identify which hormone systems are affected. 

Mechanistic studies to identify how endocrine disrupting chemicals interact with hormone systems are required. Although population effects coupled with biomarkers of exposure are strongly suggestive of endocrine disruption, the effect could be secondary to metabolic toxicity. Establishing mechanisms may avoid the need to make decisions on a weight of evidence approach alone. 

Conduct field studies based on the results of population studies and biomarker responses. The extent to which endocrine disruption occurs in situ is important in considering the scale of remedial action required. 

Animal-to-Human Extrapolations ENDOCRINE DISRUPTION CHILDREN S SUSCEPTIBILITY BIOMARKERS OF EXPOSURE AND EFFECT... 

This third part of the book will be devoted mainly to the problem of addressing complex pollution problems and how they can be studied employing new biomarker assays that exploit new technologies of biomedical science. Chapter 13 will give a broad overview of this question. The following three chapters, The Ecotoxicological Effects of Herbicides, Endocrine Disrupters, and Neurotoxicity and Behavioral Effects, will all provide examples of the study of complex pollution problems. 

In addition to the foregoing, three further examples in this list (numbers 5-7) deserve consideration. These are (5) interaction of endocrine disrupters with the estrogen receptor, (6) the action of uncouplers of oxidative phosphorylation, and (7) mechanisms of oxidative stress. Until now only the first is well represented by biomarker assays that have been employed in ecotoxicology. 

Garcia-Reyero N, Raldua D, Quiros L, Llaveria G, Cerda J, Barcelo D, Grimalt JO, Pina B (2004) Use of vitellogenin mRNA as a biomarker for endocrine disruption in feral and cultured fish. Anal Bioanal Chem 378 670-675... 

An important question in this area relates to the widespread use of exposure biomarker responses for monitoring effluents and receiving waters for endocrine disrupter activity. In oviparous species, vitellogenin is the major example of such a... 

Substances that are carcinogenic, mutagenic, or reproductively toxic (i.e., CMRs), for example, some endocrine disrupters, may pose special problems for derivation of aquatic EQSs (e.g., lack of internationally agreed tests in some cases difficulties with prediction of safe concentrations), but use of special tests for these properties is only justified for a small subset of chemicals that meet clear criteria. Furthermore, EQSs for these substances should not be derived directly from in vitro data or from biomarkers of exposure but from in vivo tests alone. 

Hutchinson TH, Ankley GT, Segner H, Tyler CR. 2006. Screening and testing for endocrine disruption in fish — biomarkers as signposts not traffic lights in risk assessment. Environ Health Perspect 114 106-114. 

Human health biomonitoring may also use animal surrogates in the environment to assess potential health hazards to humans - the proverbial canary in the coal mine . For example, chemical and biomarker analysis of bodily fluids or tissue biopsies from family pets, especially dogs, are sometimes used to assess potential chemical exposure and effects in children. This is because dogs often accompany children in the outdoor environment, and both have a tendency to (accidentally or intentionally) consume environmental media such as soil and surface water There has also been an increasing trend to use native animals as sentinel species, that is, fish, wildlife, or invertebrates that are indicators of possible human health risks from environmental hazards. For example, increased incidences of tumors or endocrine disruption in fish may indicate the presence of compounds in the water that may cause cancer or reproductive dysfunction in humans. Concern has also been raised over the increased incidence of deformities in frogs, because these may indicate an increased level of chemicals in the environment, which can cause birth defects in humans. 

Blaise, C., Gagne, F., Pellerin, J. and Hansen, P.-D. (1999) Determination of vitellogenin-like properties in Mya arenaria hemolymph (Saguenay Fjord, Canada) a potential biomarker for endocrine disruption. Environ. Toxicol., 14, 455-465. 

Eales, J.G., S.B. Brown, D.G. Cyr, B.A. Adams and K.R. Finnson. Deiodination as an index of chemical disruption of thyroid hormone homeostasis and thyroidal status in fish. In Environmental Toxicology and Risk Assessment Standardization of Biomarkers for Endocrine Disruption and Environmental Assessment Eighth Volume, ASTM STP 1364, edited by D.S. Henshel, M.C. Black and M.C. Harrass, West Conshohocken, PA, American Society for Testing and Materials, pp. 136-164, 1999. 

Endpoints like mortality, growth, reproduction, etc., are regarded as important indicators to decide about possible effects on the sustainability of populations which is in general the main protection goal. Especially when using data from mammalian toxicology for wildlife assessments but, also in connection with endocrine disruption, the relevance of data for biomarkers is difficult to evaluate. 

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