¶ … Toxicology of Bisphenol A Health - Safety

Author's note with contact information and more details on collegiate affiliation, etc.

The use of plastic in modern cultures is so ever-present it is almost invisible. Consumers trust manufacturers and distributors to sell products that are generally safe to the public. Bisphenol A is a synthetic estrogen that has been in existence for more than 100 years. It is a chemical that causes harmful effects to both humans and animals. This is a chemical that is found in baby bottles. The issue is sensitive because many countries are heavily dependent on plastic for numerous functions. This is also a sensitive issue because of the population that is specifically at risk -- infants. The paper will outline the general debate concerning the proliferation and unintended consumption of this chemical. The reader will gain a context on the issue from several sources. After analyzing the perspectives on the issue, the paper will conclude with criticisms and reflections about banning Bisphenol A from products used by the public.

A Brief Toxicology of Bisphenol A

It has been recently discovered that Bisphenol A is leaching from baby bottles throughout the United States of America and Canada. This is a chemical that is used in the creation of industrial plastics. Studies have also shown that this chemical adversely affects animals as well as humans. These are startling realizations. Infants are ingesting a harmful chemical in their newly formed bodies. Some scientists, manufacturers, and parents are alarmed. As this is a chemical that is used in a great variety of consumer products on the market besides baby bottles, some argue that removing the chemical from products for the public is drastic. Others are outraged that Bisphenol A continues to be sold without firm legislation or restraint. The paper will assess the debate surrounding the use of Bisphenol A and create a context within which an educated opinion can spring.

Bisphenol A was first created in 1895 (Maryland Public Interest Research Group, 2011). Approximately forty years later, chemists discovered another use for this -- to create hard plastics. This is a chemical that is not meant for ingestion, as the results are serious:

"Bisphenol A is a developmental, neural, and reproductive toxicant that mimics estrogen and can interfere with healthy growth and body function. Animal studies demonstrate that the chemical causes damage to reproductive, neurological, and immune systems during critical stages of development, such as infancy and in the womb." (Maryland Public Interest Research Group, 2011)

Bisphenol A affects critical systems. The adverse affects upon the body are not minor. It is obvious that ingesting a chemical at any stage of life is dangerous. Infants are particularly sensitive to health risks because they are fragile and still forming. The bones of infants do not harden for several months. They obviously lack motor control and hand-eye coordination. Infancy is a highly vulnerable stage in human development. Infants have not yet the capabilities to control the movements of their bodies or engage in speech. Any damage done to an infant has the potential to affect the child for the duration of the child's life.

Consumers and some members of the scientific community are concerned about the lack of regulation over use of Bisphenol A. Many studies have been performed on animals; some of the earliest studies in regard to Bisphenol A and rodents were done as early as 1938 (Case, 2008). People who make the plethora of products containing the chemical argue that the levels of occurrence in the general public are no need for alarm or concern. They claim that the levels of BPA are so low that negligible harm, if any, is posed to the consumer. Others, such as Professor Ana Soto of the Tufts University School of Medicine, believe that BPA is a direct link to diseases as serious as cancer:

"[We have shown] that foetal exposure at environmentally relevant levels, down to 25 ng/kg body-weight, increases the propensity to mammary cancer in rats, and alters the development of the mammary glands…We don't yet have a complete picture, but the weight of evidence suggests that BPA is harmful." (Case, 2008)

It is therefore possible for a mother who unintentionally consumes BPA through the use of an average range of consumer products could develop breast cancer. Breast cancer frequency in western women has significantly increased in the past 20 years, but really more so in the 21st century. Even if the exposure does not develop into cancer, there could be a health issue concerning the mammary glands. An infant nursing a mother with BPA in her system, as well as being...

BPA puts mothers and children at risk directly, though there are increasing occurrences of breast cancer in men as well.
As a chemical known to the west for more than 100 years, BPA's toxicology is fairly well-known and understood. It has been used as an industrial chemical for nearly 50 years. Academic researchers and government researchers have performed short-term and long-term studies on animals. Some of these tests and studies include reproduction studies, multi-generation exposure studies and a cancer bioassay, readily accessible in the scientific canon (Bisphenol A.org, 2011). According to some results, no adverse effects to the reproductive and developmental systems were found (Bisphenol A.org, 2011). The animals exposed in several studies showed no signs of cancer or any other estrogen-like effects (Bisphenol A.org, 2011). These studies support those who manufacture and distribute products containing BPA. When there are scientific, academic, and governmental studies that show there are negligible effects of exposure to BPA, companies do not want to cease products or be forced to find possibly more costly, yet healthier alternatives:

"But if there is a will for change, replacing the material may not be easy. Polycarbonate has particularly good materials properties -- impact strength and transparency -- for applications such as eye-glasses and baby bottles. BPA-based epoxy resins are very good materials for lining cans." (Case, 2008)

If the scientific community cannot come to a consensus regarding the safety of the chemical in the general public, then there is no reason to change production procedures.

Scientists argue over the effects of BPA on human since most of the studies and data reflects studies on animals. This argument is another barrier between those who want BPA removed from general consumption:

"Concerning the results from human health effect assessments, while there is general consensus concerning data on acute and local effects and genotoxicity of BPA, there is not yet agreement as regards reproductive and developmental toxicity (specifically neurodevelopment) and carcinogenicity. There is also some debate on the toxicokinetics of BPA which is still not fully resolved. Since studies in this field are based on animal experiments, data on absorption, distribution, metabolism and excretion are of utmost importance in order to understand the transferability of the experimental results to humans. It has been demonstrated that after oral intake BPA is metabolised rapidly mainly into BPA- glucuronide, which is water-soluble and can be excreted via the urine, making BPA no longer available for biological activity within the body. This deactivation of BPA is more effective in humans than in rodents and consequently humans should be exposed internally to lower circulating levels of BPA and thus would be expected to be less sensitive to BPA effects than rodents. However, currently there is a discussion whether there may be different kinetic pathways for specific populations (e.g. newborns). Some recent studies reported the detection of free BPA in blood and urine in animals and humans, leading to speculation on whether BPA might accumulate in the body and/or whether other, non-food sources may contribute to human exposure." (Aschberger et al., 2010)

Researchers disagree as to how long BPA stays in the system or if there are naturally occurring methods of consumption or exposure, but what repeats on both sides of the debate is the vulnerability of infants to the risks of BPA. That is one aspect of the debate that is not debatable. BPA hurts infants and puts them at risk for major lifelong health problems or death.

Replacing a chemical such as BPA in consumer products costs a great deal of time and money. BPA's durability and use are widespread:

"The plastic monomer and plasticizer bisphenol A (BPA) is one of the highest volume chemicals produced worldwide, with over 6 million pounds produced each year. BPA is used in the production of polycarbonate plastics, epoxy resins used to line metal cans, and in many plastic consumer products including toys, water pipes, drinking containers, eyeglass lenses, sports safety equipment, dental monomers, medical equipment and tubing, and consumer electronics." (Vandenberg, et al., 2007)

What is more costly: the inconvenience of switching to a new industrial chemical, or the preservation of infant lives? The answer to that question depends on the agenda of the person answering. Some would say that we need to find alternatives in a timely manner so that BPA can be switched out without detriment to economies or product quality. Some would say, "if it ain't…