Introduction
Bisphenol-A (usually abbreviated as BPA) is an industrial chemical organic compound that has two phenol functional groups in its molecule. It is used to make hard plastics especially polycarbonate plastic. It is produced in large quantities in United States. Its manufacture involves condensing ketones (mainly acetone) with two equivalents of phenol under acidic conditions. The acids, for example hydrochloric acid acts as a catalyst to speed up the rate of reaction. The phenol is usually put in excess s to ensure full condensation of the reactants. The reaction that leads to the production of BPA is as shown below:
CH3)2CO + 2 C6H5OH → (CH3)2C(C6H4OH)2 + H2O
In the above reaction, one mole of acetone reacts with two moles of phenol to give one mole of BPA and water. When it is produced for commercial use it has to be distilled by either extracting it under high vacuum or using more phenol before carrying out distillation. It was first reported in 1891 by A.P Dianin.
Uses of Bisphenol-A
Bisphenol-A has many uses but primarily it is used in the manufacture of polycarbonate plastics which are clear and shatter-proof. Polycarbonate is used in making safety devices and medical devices among others. In addition, BPA is also used in the production of epoxy resins that is mainly used in coating metal products like water supply pipes and food cans.Morever, BPA inertness allow it to be used in many chemicals. For example in flame retardant, pesticides, fungicides among others. It is also used in the manufacture of thermal papers for example the papers used as sales tickets. Lastly but not the least, it is a constituent in some polymers that are used in treatment of teeth for example in preventing cavities in children.
Toxicology of BPA
The word toxicology comes from two Greek words toxicos meaning poisonous and logos which means study. Therefore, toxicology is the study of chemicals’ adverse effects on living organisms. In toxicology, many studies are done.For instance, the symptoms of poisoning, various ways of poisoning, and lastly how one can know that somebody have been poisoned and if yes how to treat them. Scientist argues that all substances are poisonous but the extent to which they poison is what differs. Hence, all chemicals could be poisonous but the dose of poison and degree of exposure determines the harm that chemicals cause on living things.
According to Borrell (2010, para 16), the many uses of BPA create exposures for people as people are exposed either through the food they eat or through drinks. For instance,BPA exposes children when they take drinks from baby bottles manufactured using BPA.Other people also get exposure when they take canned food put in cans or take water from piped water that are coated inside using Bisphenol-A. Other exposures come from sheets, films, artificial teeth and laminations made using BPA.
Industries that manufacture BPA argue that it is safe. However; many reports have been issued showing many ways in which BPA is toxic to human body. For example, BPA affects both human development and reproduction as it mimics the sex hormone. Additionally; it affects mammary gland and can cause early maturity for the fetus, infants and children exposed to them.
The greatest problem is that when pregnant women are exposed to BPA them, they may get babies with birth defects or who are underweight. Moreover, in some cases the child may die even before they are born.Additionaly, they affect the behaviors, prostrate glands and brain of those in exposure and especially for children they cause slow mental development. The exposure can also lead to increased obesity and later in life can lead to prostrate cancer if the exposure is too much. In rodents like mice and rats even exposure to small doses of it can lead to structural damage of the brain, abnormal sexual behaviors among other negative effects on the animal. AS a result there has been a debate that it is wise and right to avoid it but this might be hard because BPA is a constituent in many products of plastic that are highly in use today starting from plastic water bottles that we use, food cans and baby bottle.
Safety of BPA
There has been a debate on whether BPA poses genuine health risks to people or not. Those who manufacture it support its safety while studies done on animals show that it is not safe as Environmental activists argue. This leaves consumers confused and in a dilemma whether to use things like canned food or not. For instance, a study done on rodents showed that even small exposure to BPA led to brain damage. As a result, it was concluded that exposure to BPA can also affect human beings especially infants and children exposed to it in extremely high levels. After scientists and regulatory agencies carried out some research on safety of BPA they said that it is safe and hence can be used in packaging of food and beverages. In addition, North American Metal Packaging Alliance also said that some governments like Japan, Australia and Europe concluded that when BPA is used at low doses it does not harm humans (Brady, 2010).
European Food Safety Authority (EFSA) after looking at metabolism of people came to a conclusion that small amount of chemicals including BPA that people are exposed to do not cause harm to people as they leave the body immediately. This is so because the body metabolizes them very fast and eliminates them from the body. Therefore metabolism of rats and humans differ so much and hence the effects of low doses of BPA on rodents cannot be used in explaining its effects on human beings. In addition EFSA said that babies’ health is not at danger as they also metabolize and eliminate the low doses of BPA.Lastly, exposure of human fetus to BPA is negligible because the body of the mother metabolizes the BPA and eliminate it from the body as soon as it detects it. This was said by an agency in Parma.
There are however other reports that show that products that contain BPA is not safe as BPA causes many ailments e.g. reproductive problems,diabetes,cancer,heart disease and obesity.
Analysis of the information collected
From the reports that have been given it is clear that exposure to BPA can cause many health problems to people but this is only if the exposure is so extreme. For instance, when fetuses and infants are exposed to BPA, they may suffer from prostrate and breast cancer later in life.However,the possibilities of pregnant women to miscarriage when exposed to BPA is negligible(Vaccariello,2009). As a result, BPA exposure is only a problem if exposure is too much especially for infants.
Conclusion
BPA is a chemical that is present in many plastic products and food cans. Exposure to it can cause many heath risks but current studies done to investigate its safety show that the current levels of exposure to it are safe. According to me the current exposure to BPA is safe as many agencies e.g. National Toxicology Programme of America show that for the level of BPA to be unsafe one has to take about 500 pounds of beverages and foods containing it and this is not possible. However, since infants exposed to them can get prostrate and breast cancer in future I think BPA use in making babies’ bottles should be banned.
Reference List
Borrell, B. (2010). Toxicology: The big test for Bisphenol A. Nature, 464, 1122-1124. Web.
Brady, S. (2010).Bisphenol-A in Canned Goods: Safe or not? Health News. Web.
Vaccariello, L. (2009).The seven Food Expert won’t eat. Health Living on Shine. Web.