Nancy J. Schmitt
Metropolitan Business Academy is an inter-district magnet high school that provides students with insights into the world of business. The business focus is on both entrepreneurship and college preparation. Ensuring the future availability of potable water for everyone could present business opportunities. Government regulation of water quality may impact the methods businesses use to produce their products. This unit will discuss some of the current issues facing our water supply. The lesson plans will be a collection of real life math problems which will use the challenges facing our water supply as a backdrop.
Our water systems may be contaminated by all of the medicines, antibiotics, birth control pills, vitamins, and menopausal drugs that we as a society take to feel healthier, and to get better faster. As we use these items, some of them will inevitably get into our water supply, potentially impacting our food sources and water sources. This, in turn, may be a factor in the health, growth, and evolution of humans and animals. How fast is this happening? Can it be quantified? Should we be concerned? Can this be modeled using mathematical tools, such as growth and decay models?
One of the New Haven Public Schools' Algebra I & II curricular power standards is "Collect real data and create meaningful graphical representations of the data".
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The "Evolutionary Medicine" seminar has provided food for thought as to how humans and animals evolve as their environment changes. This unit will primarily look at problems based on our water systems and the students will be able to use their problem solving skills to analyze the problem and then communicate via algebraic and graphical models their conclusions.
The question is whether or not the pharmaceuticals intended to make our lives better, more productive, and less disease-filled, are in fact getting into our water systems and over time doing more harm than good.
Scientific studies of water sources, streams and rivers downstream of large urban areas and agricultural areas have shown that there is a measurable quantity of hormones and medicines in the water that should not naturally occur. One study has found an appreciable amount of pharmaceuticals in the San Francisco Bay.
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This contamination was found in water that had already gone through the sewage treatment process.
Among the potential sources for these hormones are birth control pill and patch users. After having their particular intended effect, the body of the user disposes of these used hormones, and any excess through urine, which then enters the sanitary system. Depending on whether the users live in a rural setting or an urban setting, the hormones may flow into the water table via a septic system or into major waterways via sewage systems. It appears that neither type of system eliminates these hormones completely. While a sociological discussion of the impacts of hormonal birth control are beyond the scope of this document, the enhanced control and flexibility offered by their use is generally considered to make their introduction to society irreversible and to make them an option which will continue to be used for the foreseeable future.
In some cases, people who have leftover prescriptive and over-the-counter medicines dispose of them by flushing the remainder down the toilet. While it is understandable that most people might not understand the implications of such an action , the extent of the problem was illustrated recently, after Michael Jackson's death in 2009, when his doctor was interviewed by Diane Sawyer. While the doctor had presumably been educated in the proper cautions to take with prescription medicines, he stated that he had told Michael to flush his extra medicines down the toilet.
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Another source of hormonal contamination is thought to be the hormones that are used in livestock agriculture to increase meat production.
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For our purposes, we are not considering the effect of eating the actual meat of an animal that has been given hormones, but looking at the impact of the hormones and hormone emulators that enter the ground and groundwater, and eventually our drinking water.
Another source is the pharmaceutical companies themselves. Over-production and out-of-date medicines (including hormonal) are dumped into our waste stream and eventually find their way into our groundwater, streams, and major waterways.
A last set of contaminants to consider are chemicals from our hair and bathing products which mimic estrogens when in the water system. Even the plastic bottles that are so commonly used for water, break down in the water and act like estrogen. The chemicals produced from hair and bathing products and the breakdown of plastic bottles are categorized as phthalates.
Concern over the impact of these products is not universal. There are those in the pharmaceutical industry who state that the amounts of these hormones that find their way into our drinking water are minuscule and have no measurable impact on us.
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Some claim that there can be no harm to us because these medicines have gone through rigorous testing and are therefore safe even if they are in our drinking water.
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Still others think that hormones have always been in our water system so there is no true reason for concern. As Dr. Robert Benson, as an independent researcher - in a role separate from his regular job at the Environmental Protection Agency(EPA) -- concluded from his study in rats that " it is unlikely that humans are suffering adverse effects from current environmental exposure to these phthalate esters"
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American Chemistry Council Managing Director issues the following statement on July 9, 2009 that Dr. Benson's study confirmed his observation "that phthalates do not migrate out of products easily and they do not build up in the body; instead they begin to break down within minutes and are gone from the body in less than 24 hours"
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Early data indications are alarming; it has been demonstrated that wildlife in our major water ways have already shown biological responses that can be directly attributed to the increase of hormones or hormone emulators in the water.
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For example, male fish are becoming feminized. While the infrastructure through which our drinking water passes may dilute the hormones that wildlife are exposed to before entry into our drinking water system, dilution does not constitute elimination. Once in our drinking water, it is possible that one of the side effects of this increased hormone level is observed in the increasingly younger age at which girls are entering puberty. The impact on human males has yet be determined, but preliminary studies seem to indicate
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that there are more boys born with defects. "For example, up to 7 percent of boys are now born with undescended testicles, although this often self-corrects over time. And up to 1 percent of boys in the United States are now born with hypospadias, in which the urethra exits the penis improperly, such as at the base rather than the tip", Kristoff reports based on information from The Journal of Pediatric Urology.
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In addition there is an increasing amount of infertility among couples looking to have children that may be traceable to altered hormone levels. According to one report, infertility of married women between the ages of 20 and 24 has increased 177% from1965 to 1982.
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Other longer term impacts to humans may not have yet even begun to appear. Correlation of the hormones found with problems found in the related population is a clearly identified problem to which mathematical tools can be applied.
If there is an impact to fish, one can only suppose that other creatures in our food chain are also being impacted by the chemicals in our water. While the amounts of these contaminants in our water system may seem to be very low, the impact on our world appears to have already started. The phenomenon of male fish taking on female characteristics has been observed both in the United States and in Great Britain.
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This indicates a possible global issue rather than a national problem. Studying the potential impact on the reproduction of fish over successive generations, Jon Nash of Laboratory of Aquatic Ecology, University of Leuven, Belgium, stated "that exposure to environmentally relevant levels of [Endocrine Disrupting Compounds,] EDCs, cause very significant reductions in reproductive success. Lifetime exposure to 5ng/l of ethynylestradiol, for example, caused complete reproductive failure. Moreover, these reproductive failures were not generally caused by exposure proximate to the timing of spawning but by developmental disruption during embryonic and larval development".
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In the United States, The Food and Drug Administration has stringent testing requirements for drugs before allowing them to be placed on the market. It is reasonable to assume that the medicines are safe when used for the designated purpose and in the designated quantities. Birth control pills and hormone replacement drugs should be considered safe for the women for whom they have been prescribed. When these drugs find their way into our water supply, in small but measurable quantities, it is reasonable that there may be unforeseen consequences. There may be an impact of the small quantities of hormones on young girls and boys who would not usually be prescribed these drugs. The impact of being exposed to these hormones constantly in the water that we need for our very survival needs to be studied and quantified.
Even though hormones are naturally occurring and part of the normal growth and reproductive process, the amounts that are now occurring in our water systems are unprecedented. This issue merits greater study. Because there have been only a few generations of people since the prevalence of hormone usage by women and agriculture, the long term effects on people may not yet be evident.
From a math perspective the use of this relevant topic to discuss and use scientific notation with high school students presents itself well. There are measurable levels of these contaminants that have been determined and potential impacts of them have been identified. Further, a logical consideration is that the further hormones are from their sources the more their levels should be diluted in freshwater. This suggests a practical use of exponential decay models by the students.
Because this topic embraces current scientific studies and discusses changes in our environment that may be quantifiable and certainly of interest to high school students, it easily becomes the backdrop to several real life problems that the students would be engaged in solving. Because, there is still much that is unknown at this time about the mechanisms that are intertwined, the students can be encouraged to postulate and conjecture what the future may bring based on facts given or add new measurement to their analysis. This would in fact be a great blending of science and math with a healthy dose of high level critical thinking and research, where there may not be a single correct answer. The students will be given the opportunity to defend their answers mathematically and with cogent arguments.
The following discusses or gives many facts about the topic and brings to light some of the current scientific studies occurring literally in our backyard. What we do as individuals does indeed impact what is in our water.
