Chemical Substance Bisphenol A - Research Paper Example

?Bisphenol – A RUNNING HEAD: BISPHENOL-A [School] [School Address] Bisphenol – A 2 This paper focuses on some issues and concerns about industrial chemical – Bisphenol A. Bisphenol A can be found in various products. These products are derived from huge portion of manufactured bisphenol A that is converted into stable form of plastics - polycarbonate and epoxy resins. Under certain circumstances, the chemical can be discharged from consumer products and enter entities of the environment (water, soils, lower forms of organisms) and in human body via oral route or through the skin; and if enters the body systems it can act like “estrogen”, the female sex hormone. Numerous studies have proven that bisphenol A can disrupt the hormonal system of animals and humans. Other structural and physiological effects were noted in dysfunctions of sexuality, disrupts reproduction, triggering diabetes and respiratory illnesses, affecting mental abilities, behavior, encourages aggression and hampers learning outcomes. Other studies however are subject of controversial debates. Bisphenol – A 3 Introduction A review of greater than eighty (80) bio-monitoring investigations from nine (9) nations suggests exposure to industrial chemical, bisphenol A or BPA and this issue is ubiquitous in people from all over the world (Vandenberg, et al, 2010). Bisphenol-A (BPA) is one of the top produced volume of chemicals worldwide (Vandenberg, Maffini, Sonnenschein, Rubin and Soto, 2009) with around 3.8 million tonnes production in 2006 and corresponds up to 100,000 40-tonne HGVs. The largest share of this chemical is further processed in Europe area in a form of polycarbonates and epoxy resins, with over 6 billion pounds generated each year and over 100 tons discharged into the atmosphere by annual production. BPA, the building block of polycarbonate plastic (PasticEurope, 2009), is also one of the first synthetic substances that was known and has similar mode of action to that of the sex hormone of females known as estrogen. (Doods, 1936). Nevertheless, the said substance did not become successful in medical therapy since diethylstilbestrol (DES), a more potent synthetic estrogen was discovered (Doods, 1938). Years after, Bisphenol A became an industrial chemical, and exist in several everyday products, however, research reports found out that it can affect human hormone system, which presently have been the subject of dispute. Polycarbonate containers used as reusable food containers, some paper and cardboard, polyvinyl chloride and others have been examined for BPA content. Also, residual BPA were examined leaching from the epoxy resins lining cans all throughout specific foods including vegetables, canned pet foods, and fish.(Vandenberg, Maffini, Sonnenschein, Rubin and Soto, Bisphenol – A 4 2009), The experts added that canned infant formula and others were found to contain BPA which may have leach from the epoxy resin. Moreover, it is very alarming to find out that in blood serum samples, median levels of unconju­gated BPA (biologically active) were higher compared to the levels predicted by toxicokinetic models, which form the basis of United States regulations for the said compound, arriving at the range that has been presented to cause adverse effects in animals (Environmental Health Perspectives, 2010). Objectives This paper is directed to highlight controversies over bisphenol A, a ubiquitous chemical produced from polyvinyl chloride plastics, polycarbonate and epoxy resins. It also presents relevant information regarding threats, health risks and interventions involved in the contamination process during the past decade and until recently. Literature Review Bisphenol A is a chemical substance, found mostly in very common products such as CDs, DVDs, plastic bowls, drinking bottles and containers for food water boilers, mobile telephones, motorcycle helmets, roof coverings, computer housings water boiler, safety glass (glassy polymers), Car parts (transparent plastic parts), reflectors, parts for plugs and switches, spectacle glasses, flooring, Beverage and food cans, varnishes (as coatings for appliances and equipment), adhesives, computers and several household products and technical appliances which are composed of very stable plastics, known as polycarbonates (Thieme Chemistry, 2009). Bisphenol A alone cannot be used (Munstermann, 2004); but, it can be released on the Bisphenol – A 5 process or after dental treatment (Vandenberg, Hauser , Marcus , Olea and Welshons, 2007). Source: German Federal Environment Agency Press, 2010 Another special application of Bisphenol A is in dentistry, whereby fillings and sealing materials (like epoxy resin, and dental composites) are made from substances like bisphenol A -dimethacrylate (bis-DMA) and bisphenol A glycidyl methacrylate (bis-GMA), both are based on bisphenol A (American Chemistry Council, 2009). The National Institute of Environmental Health Sciences (NIH-HHS, 2010) reported that the firsthand source of BPA exposure for most individuals is through the diet. Air, water and dust could be possible sources as well. Similarly, BPA in food and beverages accounts for the majority of daily human exposure. Furthermore, through the use of products which are made of PVC, bisphenol A can enter the environment; but the discharged quantity into the environment cannot, be reliably estimated (European Commission, 2003). As a rule, bisphenol A can possibly enter the environment through the waste water (European Commission, 2008). On the other hand, toxicology studies were able to determine the BPA maximum tolerated dose which is 1000 mg/kg body weight (BW); the reference dose of 50 g/kg was calculated using a safety factor of 1000 (Welshons, Thayer, Judy, Taylor, Curran, and Saal, 2003). Bisphenol – A 6 Source: German Federal Environment Agency Press, 2010 Consequently, the FDA formed a task force in order to address the possible health effects of BPA exposure to humans. (vom Saal & Welshons, 2006). On the contrary, The European Food Safety Authority (EFSA) believed that bisphenol A does not exhibit risk to human health, based on studies conducted with rodents and are regarded as highly relevant. The result of the investigation shows that harmful effects significant to the evaluation below an intake of 5 milligrams for every kilogram body weight each day cannot be established. They further elaborated that the daily human intake stays well beneath the tolerable daily dose of 50 ?g per kilogram body weight (European Commission, Bisphenol – A 7 2003). There is scientific consensus however, that exposure to increase levels of BPA can cause harmful reproductive effects in mammals. There is, but, growing concern regarding low-dose exposures among the general public, and among several scientists. Moreover, the scenario is sharpened by the fact that exposures to BPA within the populations are highest in infants. Thus, scientific debate on BPA safety is likely to continue, and would challenge further government and non-government policies. Conclusions The data collected by experts are sufficiently sturdy to raise concerns and awareness about the potentially injurious impact of reproductive and endocrine-disrupting chemicals on human development. The attempts to extrapolate evidence from human or animal studies should be done with extra care since differences among species as well as of strains have been reported as far as variety of parameters are concerned. The evaluations made on bisphenol A expressed “some concern” understandably because several of the developmental effects revealed in laboratory animals were noted at exposures to bisphenol A the same as those experienced by humans. Jointly, the findings could not be disregarded. The same conclusions were generated by Health Canada (2008) examining the potential association between bisphenol A and the negative trends in human health (vom Saal et al. 2007). However, these predicaments bring challenges as well as opportunities to bridge the uncertainty and data gaps which should be given attention to fully understand bisphenol A’s capacity to harm human development. Bisphenol – A 8 In summary, there is a need of a comprehensive up-to-date analysis by regulatory agencies to continuously evaluate the potential hazards BPA exposure brings to humans from doses below the preceding LOAEL of 50 mg/kg/day. Recommendations In the light of the foregoing facts presented, the following are recommended: Collaboration with the Centers for Disease Control and Prevention, government leaders and academic investigators must be effectively facilitated in order to continue the evaluation of bisphenol A exposures to humans, particularly infants in children < 6 years of age and neonates at healthcare settings. Collaborative research across institutions must strongly be encouraged and promoted, since there is a need to obtain up-to-date information for constructing models from living samples. Collectively, the outcomes of these studies should start to chip away at the controversies, uncertainties and research gaps; providing a better perspective about the potential threats of bisphenol A to public health. In particular, if individuals are concerned about the pressing problem, can make some personal initiatives or actions to reduce bisphenol A exposure and these are as follows (Munstermann, 2004): The use of plastic containers with the #7 label on the bottom must be avoided; polycarbonate plastic containers placed in the dishwasher must not be washed using harsh detergents; polycarbonate plastic food containers must not be used when heating food using microwave; The use of of canned foods must be reduced; instead of using plastics, opt for porcelain, stainless steel or glass containers, especially if food is hot; Mothers should opt to use BP free infant formula bottles. Bisphenol – A 9 REFERENCES American Chemistry Council, PlasticsEurope and Japan Chemical Industry Association. (2009) Resin dental sealants and bisphenol A oral exposure.. PC/BPA Global Group. Retrieved March 24, 2010 from http://www.bisphenol-a.org/human/dental.html European Commission. (2003). ISOPROPYLIDENEDIPHENOL (BISPHENOL-A). European Union Risk Assessment Report 4,4‘- Office for Official Publications of the European Communities, Luxembourg. European Commission. (2008). -ISOPROPYLIDENEDIPHENOL (BISPHENOL-A). Updated European Risk Assessment Report 4,4‘Office for Official Publications of the Euro-pean Communities, Luxembourg. Gies, A. (2007) Problems in Assessing low dose ef­fects of endocrine disruptors. In: Reproductive Health and the Environment. , Springer, 283-296. German Federal Environment Agency (2010) Bisphenol an industrial chemical with adverse effects. Press Office, Worlitzer Platz 1, 06844 Dessau-Ro?lau, Germany. PlasticsEurope (2008) Applications of bisphenol A. Retrieved March 24, 2010 from http://www.bisphenol-a-europe.org/uploads/BPA%20ap­plications.pdf Vandenberg, L.N., Hauser R., Marcus M., Olea N., and Welshons V.W. (2007). Human exposure to bisphe­nol A (BPA). Reproductive Toxicology 24: 139-177. Welshons , W.V., Thayer, K.A., Judy, B.M., Taylor, J.A, Curran, E.M., and vom Saal FS (2003) Large effects from small exposures: Mechanisms for endocrine-disrupting chemicals with estrogenic activity. Environmental Health Perspectives, 111:994–1006 vom Saal, FS, and Welshons WV (2006) Large effects from small exposures. II. The importance of positive controls in low-dose research on bisphenol A. Environmenal Research, 100:p 50–76 vom Saal, F. S. and Hughes, C. (2005) An extensive new literature concerning low-dose effects of bisphenol a shows the need for a new risk assessment. Environmental Health Perspectives, 2 (13); 8, p 925-928. Read More