Experts probe plastic bottles’ chemical link to ill-health

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There is growing concern over the use of plastics for food and water packaging following studies linking plastic container’s chemical, Bisphenol-A (BPA), to degenerative diseases. More worrisome is the call for a ban on the use of plastic containers containing the chemical. CHUKWUMA MUANYA reports.

IN recent times there have been several reports on the effect on health of a chemical used in making plastic bottles, especially baby feeding bottles.

The chemical, Bisphenol-A (BPA), shown to be a hormone disrupter has been linked to serious health problems like breast cancer, reproductive and neurological abnormalities.

Indeed, BPA is widely used to make polycarbonate plastics such as those in the baby bottles, water bottles and compact discs resistant to shattering, and is an ingredient in the resins used to line food cans. The chemical has been shown to leach into food or water, however, and a number of studies, mostly on rodents, have linked it to disruptions of the hormonal and nervous systems.

Research has shown, however, that the chemical mimics the hormone estrogens in the body, and studies have implicated it in reproductive and developmental defects, including abnormalities of the brain and prostate. The United States (U.S.) National Institutes of Health has also expressed concern BPA might lead to behavioural changes in children and infants.

A school of thought argues that most of the studies were conducted in animal models and trace amount of the chemical is not harmful, put recent researches suggest that the same effect is possible in humans even in trace quantity.

In the first direct evidence that BPA can be harmful to primates, the chemical was observed to produce neurological problems in monkeys. Researchers in a study conducted by researchers from Yale School of Medicine, United States, and published in the Proceedings of the National Academy of Sciences write: “Our findings suggest that exposure to low-dose BPA may have widespread effects on brain structure and function.”

These recent findings have put food regulatory agencies around the world on alert. The National Agency for Food and Drug Administration (NAFDAC), when contacted by The Guardian said it is on alert and is monitoring the situation.

NAFDAC’s Director of Enforcement, Alhaji Hashim Ubale Yusuf told The Guardian: “We are working with the Federal Ministry of Environment at the moment and we are going to come out with a joint statement. We are on alert on BPA containing plastics and we are keeping a data base.”

According to the Associated Press report, the California State Senate has voted for the second year in a row to ban the manufacturing, sale or distribution of children’s food and drink containers that contain the chemical BPA.

Lawmakers voted 21-16 last Tuesday to approve a bill by Democratic Sens. Fran Pavley of Agoura Hills and Carol Liu of Pasadena. A similar measure passed the Senate last year but died in the Assembly.

The proposal would prohibit the use of more than a trace amount of BPA in food and drink containers designed for children age three and under. BPA is commonly used in making plastics and resins.

Animal studies indicate it interferes with infant hormone levels. The FDA has found that trace amounts of the chemical are not dangerous.

Also, the U.S. state of Connecticut has signed into law a bill banning the use of BPA from baby bottles and infant food containers.

The law, passed late last week and due to go in to effect in October 2011, received bi-partisan support in the state legislature in the wake mounting concern over inclusion of the chemical in food packaging, particularly for babies and children. The legislation also outlawed BPA use in reusable food and beverage containers.

Opponents of BPA say it can act as an endocrine disruptor and has been linked to a range of illnesses including heart disease and cancer.

However, the move was condemned by the American Chemistry Council (ACC), which said the ban was imposed in the face of what the body described as “worldwide consensus among regulatory agencies that BPA can be safely used in food contact products”.

The ACC said: “The law does not promote health or safety. It hurts Connecticut businesses that can no longer manufacture these highly valued products and Connecticut consumers who will no longer find them on store shelves.”

In the most current study, researchers exposed monkeys to BPA levels that the United States Environmental Protection Agency (EPA) has ruled safe for humans. “Our goal was to more closely mimic the slow and continuous conditions under which humans would normally be exposed to BPA,” researcher Csaba Leranth said.

The monkeys went on to develop mood disorders and irregular brain function. The U.S. National Institutes of Health’s National Toxicology Programme recently reaffirmed its findings that current research supports concerns over BPA’s effects on the developing brains and endocrine systems of infants and children.

The National Toxicology Programme has no ability to regulate the chemical, however, and can only make recommendations to the EPA and United States Food and Drug Administration (FDA). The FDA continues to classify BPA as safe, basing its ruling only on the findings of two industry-funded studies.

“Unfortunately the regulatory agency charged with protecting the public health continues to rely on industry-based research to arrive at its conclusions, rather than examining the totality of scientific evidence,” said Rep. John D. Dingell, chair of the House Energy and Commerce Committee, which is investigating the FDA’s treatment of the BPA issue.

The Washington Post reports that after years of insisting BPA posed no threat to the health of babies, six larger manufacturers of baby bottles have announced they will stop shipping new baby bottles made with the chemical. According to the report, no existing baby bottles are being recalled, however. Nor are they being taken off the shelves of retailers.

Critics insist that the baby bottles being purchased and used by babies right now still contain BPA. But the American Chemistry Council, an industry group representing the business interests of chemical companies, insists that BPA is perfectly safe for infants and babies.

According to another new study conducted by researchers from the University of Rochester and published in the journal Environmental Health Perspectives, BPA remains in the body significantly longer than scientists had previously believed.

Scientists have known for some time that the chemical accumulates in the body, but had believed that it was water soluble and passed out quickly through the urine.

In the current study, researchers tested urine levels of bisphenol A among 1,469 adults after fasts of different lengths to determine if this was really the case.

The researchers found roughly similar levels of the chemical in the urine of those who had been fasting for 8.5 hours as in those who had been fasting for 24. This suggests that either the participant were ingesting bisphenol A from a non-dietary source or that the chemical remains in the body longer than previously thought, perhaps in the fat cells.

The findings raise significant new health concerns about the chemical, researcher Richard Stahlhut noted. “If it leaves the body quickly, then it reduces the amount of time when it can cause problems. If it does cause problems, obviously if it stays around much longer, then that changes the game,” he said.

Prior research has found a correlation between a high body burden of bisphenol A and a higher risk of diabetes, cardiovascular disease and liver problems.

Researchers say prolonged exposure to BPA may affect the brain’s ability to create neurological connections needed for learning and memory. A study in the Proceedings of the National Academy of Sciences found that low doses of BPA impaired the creation of synapses in the brain, affecting neurons’ ability to communicate.

A biomedical professor at the University of Guelph, Neil MacLusky, said: “The ability of the brain to remain plastic and to respond to things by changing its connection is a critical part of brain function, it’s important for learning and memory, it’s important for mood swings, for depression. It dramatically impairs the formation of synapses in the regions of the brain where such processes take place.”

The use of bisphenol A in plastic bottles, baby bottles and plastic toys came under scrutiny a few months ago, after Health Canada found it to be dangerous to babies and the environment.

But this study focuses on the effect of bisphenol A on adults. The researchers exposed African green monkeys to a daily dose of 50 micrograms per kilogramme, an amount declared safe for humans by the FDA, over a month-long period.

“This is the very first study to look at a primate exposure over a long period of time,” said MacLusky. “One of the biggest surprises of the study is how powerful BPA is.”

In the study, synaptic activity was diminished when BPA was introduced in primates, who were also given estrogen, a hormone that normally boosts synaptic processes. Even at low levels, BPA reduced the density of synaptic activity taking place in the brain.

Although the actual exposure of humans in Canada is “much lower than the daily amount,” the study is a reminder of the implications of continuous exposure.

“What is the effect of having this around for your whole life? We don’t know that yet,” MacLusky said. “Governments should really be looking more carefully at what the safe daily limits are, and it is probably wise to not include BPA in things that people are going to eat from and drink from.”

Canada is reported to be the first country in the world to take action on BPA, thanks to their Chemicals Management Plan. This Plan was introduced in 2006 to review the safety of widely-used chemicals that have been in the marketplace for many years, and to update their knowledge and understanding of these chemicals.

A Fact Sheet on BPA by the Canadian government reads: “The current research tells us the general public need not be concerned. In general, most Canadians are exposed to very low levels of BPA, therefore, it does not pose a health risk.

“Our focus now is on the health of newborns and infants under 18 months. Science tells us that exposure levels are below those that could cause health effects; however, due to the uncertainty raised in some studies relating to the potential effects of low levels of BPA, the Government of Canada is taking action to enhance the protection of infants and young children.

“Studies have shown the main sources of exposure for newborns and infants are from bisphenol A migrating from the lining of cans into liquid infant formula and migrating from the polycarbonate baby bottles into the liquid inside following the addition of boiling water.

“Therefore, the Government of Canada will continue to ensure that levels of BPA in infant formula are kept at the lowest levels achievable by carefully reviewing pre-market submissions of infant formula and continuing to work with the food packaging industry to reduce levels of BPA in infant formula to the lowest levels possible. We will also evaluate alternatives to BPA for infant formula can linings on a priority basis. The Government of Canada is also moving forward with legislation to ban the importation, sale and advertising of polycarbonate baby bottles.”

On environmental concerns, the Fact Sheet reads: “Science shows that bisphenol A is entering the environment through wastewaters, washing residues and has been found in some leachate from landfills. It also breaks down slowly in the environment when there is a lack of oxygen. The combination of the slow break down of bisphenol A and its wide use in Canada means that over time, this chemical could build up in our waters and harm fish and other organisms.

“As a precautionary measure, Environment Canada is considering a regulation that would set a limit for the maximum concentration of bisphenol A that can be released in effluent to the environment. The regulation would also require facilities using bisphenol A to implement best management practices to ensure that it is handled and disposed of safely. These actions will keep the levels of bisphenol A being released to the environment at safe concentrations for fish and other aquatic life.”

The document noted that Bisphenol A does not pose a risk to the general population, including adults, teenagers and children.

“Consumers can continue to use polycarbonate water bottles and