Origins And Effects Of Endocrine Disrupters On Human Health Research Paper Sample

Introduction

The purpose is the paper is to present scientific evidences to confirm the presence of endocrine disruptor (ED) in the environment and the risk on human health upon exposure to this compound. The paper also presents scientific records on the origins of this substance in the environment and various effects that it can create to living organisms.

Background

There is an ongoing debate over the effects of endocrine disrupters (ED) or xenoestrogens on human being. Scientists have shown the adverse effects of this compound on human health, but there are skeptics who do not think that there is enough evidence to support the claim that endocrine disrupters are causing physiological and behavioral changes in human beings.
Xenoestrogen is a chemical compound that mimics the natural female sex hormone (estrogen) and can cause early puberty (precocious puberty) and many other ill effects in human physiology and development . The xenoestrogen compound includes chemical such as Alkyl phenols from detergents, DDT from the use of herbicides, Polychlorinated Biphenyls (PCB) from heat insulator liquid, Bisphenol-A (BPA) from plastic containers and phthalates from plastic products . Xenoestrogen compounds are derived from plastic, medications, herbicides and many other chemical applications. This compound is present in the aquatic environment, and the concentration of these compounds can be quantified using separation techniques.
The presence of environmental pollutant (including xenoestrogen) is known to cause skewed sex ratio in animal populations, reduced fertility in birds, feminization and demasculinization of male animals . The presence of xenoestrogen in animals and in human body can be detected using biomarkers. A recent study on Inuit population indicates that this substance and other persistent organic pollutants (POP) are found in serum and adipose tissue . Furthermore, studies indicate that natural estrogen and xenoestrogen may interact with each other and there is a certain concentration of xenoestrogen that can cause clinical signs in human physiology. This concentration level is known as Total Xenoestrogenic Burden (TEXB) that can be measured using modern laboratory technology such as High-Pressure Liquid chromatography (HPLC) fractionation .

Methods

The methods used in this paper mainly consist of review of current research to establish the evidence that xenoestrogen in present in the environment (typically in aquatic environment) and how this substance is introduced to the environment. Furthermore, the review will also compile evidence on the etiology of xenoestrogen accumulation in human body and how this substance acts at the molecular level. The paper organizes reviews of current evidences on the effects of xenoestrogen to human’s health, as well as the effects of this substance on wildlife population. Arguments to support the claim that xenoestrogenic substance will have effects on human’s health will be developed based on the evidences of origin, pathways, mechanism and impacts of xenoestrogenic substance.

Results

The sources of xenoestrogens range from simple everyday items such as food storage containers, personal care and medications to pollutants such as pesticides and Polychlorinated Biphenyls (PCB) that come in contact through daily use or through environmental contamination . The most common pathways for xenoestrogen to enter human body are from contaminated river and coastal waters , or from contaminated ground water . Xenoestrogen may also enter human body through consumption of contaminated fish and bioaccumulation of this substance in fish tissue.
Effects of xenoestrogens in wildlife species (especially reptiles and amphibians that live in the water bodies) consist of sex reversal between males and females; demasculinization of male-specific behavior; and also risk of effects being passed on to the next generation . Xenoestrogen may disrupt the brain development, as shown in the experimental evidence leading to the disruption of the sexually dimorphic behavior and the sexually dimorphic areas in the brain of mice . There is a possibility that the same effects can occur in human development process.
The effects of xenoestrogen on human physiology have been well documented, and these effects include disease susceptibility, reproductive disorder due to interference with natural estrogen and disruption in embryonic development. At molecular level, xenoestrogen is also known to cause disruption of cell’s function and shifts in the DNA methylation process that eventually affects genomic sequence crucial for fetal growth and development . The effects of xenoestrogen on human are summarized in Table 1.
Research on animal as a model for human system reveals some important information that may be relevant to human cases. The molecular pathway of xenoestrogen effect can be described by interrupting signaling pathway of endocrine at fetal, neonatal and perinatal stages of the development. Consequently, xenoestrogen exposure leads to the disruption in the brain and behavior . Interruption of endocrine signaling also causes disruption in fetal reproductive development due to the disruption in the gametogenesis process. This leads to the deleterious effects or reproductive failure among the subsequent generation . The molecular mechanism of precocious puberty is also studied using animal model. The mechanism involves the abnormal increase of Gonadotropin Releasing Hormone (GnRH) production, due to the decrease in the production of inhibitor peptide known as RFRP3. The decrease in this inhibitor peptide occurs upon neonatal exposure to xenoestrogen .

Conclusions

This paper has collected scientific evidences to establish the following facts:
Xenoestrogen is present in the environment from daily items and from pollution or contamination of environment;
The presence of this substance is known to affect aquatic wildlife species and to cause physiological and endocrinal disruptions;
Xenoestrogen may enter human body through water and food. The presence of this substance can be identified using biomarker;
Xenoestrogen interacts with endocrine system and also embryo. This results in various reproductive and developmental disorders; and
Research using animal model sheds additional information on the impacts of xenoestrogen at organ, tissue and molecular levels.
The above facts show that there is enough scientific evidence to make a clear connection between the presence of xenoestrogen and the human health. Furthermore, the use of rodents as a model for human system can provide opportunity for studies that cannot be conducted on human.
However, in some cases, there is a constraint in making solid correlation between xenoestrogen and its exact effect on human physiology due to the complexities of chemical interactions between estrogen, xenoestrogen and other signaling substances.
The use of rodents as a model for human physiology faces constraints such as compatibility of animal’s physiological system with human’s system. The animals’ response to a treatment or experimentation may not reflect the actual response in human’s system upon receiving the same treatment or experimentation. Despite the limitations, recent studies on the aspect of environmental pollutant (specifically on xenoestrogen) have provided a solid base to support the argument raised by Michelle Trankina mentioned in Easton (2011).
There are options for eliminating xenoestrogen from the environment through various bioremediation strategies for organic pollutant . However, important aspects for environmental management include preventing contamination of organic pollutant such as xenoestrogen. This can be achieved by implementing proper political and technical instruments such as effective implementation of good environmental policies. The development of good environmental policies requires high level of awareness among policy makers and general public on xenoestrogen contamination.
The understanding of xenoestrogen’s effects on human health can be increased through environmental awareness programs. Findings from researches in this paper (as well as many other ongoing researches) can be used as ingredients in developing awareness raising materials. This high level of awareness is a main factor for creating and influencing environmental policies. Eventually, this will become a strategy for preventing xenoestrogen contamination in the environment, and prevent the adverse effects of this chemical on human’s health.

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