Based on an article from Science News OnLine In this articleA pollutant called bisphenol AIts not just baby bottles and plastic tablewareIs bisphenol A hazardous?What the Society of the Plastics Industry (SPI) has to sayPlaying it safeA pollutant called bisphenol A One could never imagine that a babys bottle could possibly be considered harmful. However, a recent Japanese study has found that plastic containers and other tableware that is used to serve food have inherent adulterants that mimic hormones. Approximately 95% of all baby bottles on the market today are made of polycarbonate. This plastic is a polymer - a chainlike molecule that is built by linking up individual units of a common chemical. In this case, each link is a molecule of bisphenol A. Toxicologist Koji Arizono of the Prefectural University of Kumamoto, Japan and his colleagues tested 10 different brands of polycarbonate baby bottles purchased in the United States, Germany, Japan, Korea, Malaysia, and the Philippines - along with other types of clear plastic tableware. When heated, all leached bisphenol A, a chemical that mimics the hormone estrogen, into the liquids they held. British chemists found that bisphenol A has the same effect as weak estrogen as long back as 1936. However, since only traces of unbound bisphenol A were detected in plastics and since the use of plastic was still not prevalent for food containers, this finding was largely ignored. The findings of a study conducted by the FDA two years ago supported the hypothesis that heating baby bottles and juice caps made of polycarbonate did result in the leaching of unlinked bisphenol A. However, the FDA came to the conclusion that the amount of bisphenol A that leached into a fatty material designed to simulate infant formula was negligible. But Arizonos research indicates that through normal use, polycarbonates leach more bisphenol A than was earlier believed. They found that the concentration of bisphenol A leached was in the same range that caused abnormalities in rats. To investigate how wear and tear might affect the leaching of this chemical, Arizonos team compared rates of bisphenol A released from shiny new baby bottles and from bottles that were hazy and crackled, reflecting years of use. Arizono put water at the temperature of 90 degrees centigrade in contact with the bottles for 30 minutes and measured how much bisphenol A ended up in the water. For new baby bottles, the water picked up between 1 and 3.5 parts per billion (ppb) bisphenol A. Water heated in used but relatively clear bottles sometimes picked up as much as 6.5 ppb. Water in very worn and heavily scratched bottles acquired between 10 and 28 ppb of the compound. Its not just baby bottles and plastic tableware The Japanese study also examined bisphenol A-migration from the plastic resin used to line food cans. Results showed that while soft drinks stored in plastic-lined cans picked up less than 1 ppb of bisphenol, coffee acquired a shocking 90 to 127 ppb of the substance. Earlier studies also support these findings. Nicolas Olea and his colleagues at the University of Granada analyzed the contents of 20 different brands of canned foods purchased at various groceries in Europe and the United States. The results of his study showed that measurable quantities of bisphenol A turned up in roughly half of all foods sampled. The chemical leached from the plastic resins used to line the food cans. Oleas team also found that bisphenol A leaches from plastic resins used to seal tooth surfaces. Results of their study showed that newly applied sealants left measurable quantities of bisphenol A in saliva. In one case, they even found traces of the substance in the saliva after a gap of two years. Is bisphenol A hazardous? Pollutants that imitate hormones " especially estrogen " are a major environmental concern. Findings of some animal studies indicate that such pollutants might make an individual more prone to developing certain kinds of cancers. In the developmental stages, exposure to these hormones could disrupt the normal growth and function of the reproductive tissues and the brain. However, while numerous animal and cellular studies on bisphenol A indicate a variety of biological effects, whether it has implications for peoples health is still debatable. The significance of biological changes seen in animals exposed to bisphenol A has been the subject of considerable discussion. In some cases, adults that were exposed to the hormone-like substance during the fetal stage showed curious abnormalities. Frederick S. vom Saal at the University of Missouri-Columbia found that the prostates of some mice fetally exposed to 2 ppb of bisphenol A were larger than normal, though no cancers were present. However, plastic industry scientists have been unable to replicate vom Saals findings. Clearly, the jury is still out on this issue. What the Society of the Plastics Industry (SPI) has to say The Society of the Plastics Industry (SPI) obviously has an opposing view. They argue that four decades of research show that polycarbonate food containers and baby bottles are safe. In addition, they have found that since parents have made the switch from glass to plastic baby bottles, children suffer fewer dangerous accidents. The SPI has taken a stand that small quantities of bisphenol A pose no health hazard. Therefore, the mere fact that plastic bottles do leach the chemical should not be used to scare the consumer. Playing it safe The National Environmental Trust along with 11 other consumer, health, religious and environmental organizations has petitioned the FDA to take some corrective measures in this regard. However, FDA has not formally responded to the petition. The National Environmental Trust has advocated that by way of abundant caution, parents should switch to baby bottles and foodware that is not made of polycarbonates. For instance, baby bottles manufactured from a pliable, milky coloured plastic contain no polycarbonates. However, if parents choose to continue using bottles made of polycarbonates, it is suggested that they discard any that show signs of wear and tear such as a somewhat cloudy, crackled appearance. It is also recommended that food and drinks be heated in containers other than the plastic ones and only be transferred in to the plastic containers once they are cool enough to eat and drink.
Based on an article from Science News OnLine
A pollutant called bisphenol A
One could never imagine that a baby's bottle could possibly be considered harmful. However, a recent Japanese study has found that plastic containers and other tableware that is used to serve food have inherent adulterants that mimic hormones. Approximately 95% of all baby bottles on the market today are made of polycarbonate. This plastic is a polymer - a chainlike molecule that is built by linking up individual units of a common chemical. In this case, each link is a molecule of bisphenol A.
Toxicologist Koji Arizono of the Prefectural University of Kumamoto, Japan and his colleagues tested 10 different brands of polycarbonate baby bottles purchased in the United States, Germany, Japan, Korea, Malaysia, and the Philippines - along with other types of clear plastic tableware. When heated, all leached bisphenol A, a chemical that mimics the hormone estrogen, into the liquids they held.
British chemists found that bisphenol A has the same effect as weak estrogen as long back as 1936. However, since only traces of unbound bisphenol A were detected in plastics and since the use of plastic was still not prevalent for food containers, this finding was largely ignored. The findings of a study conducted by the FDA two years ago supported the hypothesis that heating baby bottles and juice caps made of polycarbonate did result in the leaching of unlinked bisphenol A. However, the FDA came to the conclusion that the amount of bisphenol A that leached into a fatty material designed to simulate infant formula was negligible. But Arizono's research indicates that through normal use, polycarbonates leach more bisphenol A than was earlier believed. They found that the concentration of bisphenol A leached was in the same range that caused abnormalities in rats.
To investigate how wear and tear might affect the leaching of this chemical, Arizono's team compared rates of bisphenol A released from shiny new baby bottles and from bottles that were hazy and crackled, reflecting years of use. Arizono put water at the temperature of 90 degrees centigrade in contact with the bottles for 30 minutes and measured how much bisphenol A ended up in the water. For new baby bottles, the water picked up between 1 and 3.5 parts per billion (ppb) bisphenol A. Water heated in used but relatively clear bottles sometimes picked up as much as 6.5 ppb. Water in very worn and heavily scratched bottles acquired between 10 and 28 ppb of the compound.
It's not just baby bottles and plastic tableware
The Japanese study also examined bisphenol A-migration from the plastic resin used to line food cans. Results showed that while soft drinks stored in plastic-lined cans picked up less than 1 ppb of bisphenol, coffee acquired a shocking 90 to 127 ppb of the substance. Earlier studies also support these findings. Nicolas Olea and his colleagues at the University of Granada analyzed the contents of 20 different brands of canned foods purchased at various groceries in Europe and the United States. The results of his study showed that measurable quantities of bisphenol A turned up in roughly half of all foods sampled. The chemical leached from the plastic resins used to line the food cans.
Olea's team also found that bisphenol A leaches from plastic resins used to seal tooth surfaces. Results of their study showed that newly applied sealants left measurable quantities of bisphenol A in saliva. In one case, they even found traces of the substance in the saliva after a gap of two years.
Is bisphenol A hazardous?
Pollutants that imitate hormones " especially estrogen " are a major environmental concern. Findings of some animal studies indicate that such pollutants might make an individual more prone to developing certain kinds of cancers. In the developmental stages, exposure to these 'hormones' could disrupt the normal growth and function of the reproductive tissues and the brain. However, while numerous animal and cellular studies on bisphenol A indicate a variety of biological effects, whether it has implications for people's health is still debatable.
The significance of biological changes seen in animals exposed to bisphenol A has been the subject of considerable discussion. In some cases, adults that were exposed to the hormone-like substance during the fetal stage showed curious abnormalities. Frederick S. vom Saal at the University of Missouri-Columbia found that the prostates of some mice fetally exposed to 2 ppb of bisphenol A were larger than normal, though no cancers were present. However, plastic industry scientists have been unable to replicate vom Saal's findings. Clearly, the jury is still out on this issue.
What the Society of the Plastics Industry (SPI) has to say
The Society of the Plastics Industry (SPI) obviously has an opposing view. They argue that four decades of research show that polycarbonate food containers and baby bottles are safe. In addition, they have found that since parents have made the switch from glass to plastic baby bottles, children suffer fewer dangerous accidents. The SPI has taken a stand that small quantities of bisphenol A pose no health hazard. Therefore, the mere fact that plastic bottles do leach the chemical should not be used to scare the consumer.
Playing it safe
The National Environmental Trust along with 11 other consumer, health, religious and environmental organizations has petitioned the FDA to take some corrective measures in this regard. However, FDA has not formally responded to the petition. The National Environmental Trust has advocated that by way of abundant caution, parents should switch to baby bottles and foodware that is not made of polycarbonates. For instance, baby bottles manufactured from a pliable, milky coloured plastic contain no polycarbonates. However, if parents choose to continue using bottles made of polycarbonates, it is suggested that they discard any that show signs of wear and tear such as a somewhat cloudy, crackled appearance. It is also recommended that food and drinks be heated in containers other than the plastic ones and only be transferred in to the plastic containers once they are cool enough to eat and drink.
