On Friday, the government of Canada said it would begin a 60-day public comment period on whether to ban baby bottles containing bisphenol A. And water bottle manufacturer Nalgene announced April 18 it would phase out use of BPA in its containers in response to public concern about the chemical. The NTP report focuses primarily on the possible reproductive and developmental effects of BPA (such as changes in fertility, birth weight, and the development of certain brain regions), not on cancer. However it does note that in some animal studies, BPA has shown effects on breast and prostate tissue, as well as on how early puberty occurs. These effects could be linked to cancer, the report says, but the authors caution that there is not enough evidence to know whether BPA causes cancer — in animals or in people. The health effects of BPA are being studied because so many people are exposed to it on a daily basis. The chemical is widely used in plastic water and baby bottles, food packaging, compact discs, and other consumer products; plastics made with BPA usually have the number 7 on the bottom. One survey conducted by the US Centers for Disease Control and Prevention detected BPA in the urine of 93% of people age 6 years and older. Most Studies in Animals, Not People The effects on breast and prostate tissue were seen in baby rats. When pregnant rats were injected with BPA, their female pups showed breast tissue changes that some researchers suspected might eventually progress to breast cancer, and male pups showed prostate tissue changes that researchers thought might eventually lead to prostate cancer. Some studies also showed that female mice entered puberty earlier than normal. In humans, early puberty is linked to higher breast cancer risk. However, the report is careful to explain that these animal results are difficult to apply to humans. For one thing, the studies did not follow the pups long enough to see whether cancer actually developed. Another problem is that while people are primarily exposed to BPA through their diet, the rats and some of the mice were injected with BPA (some mice got oral doses). The different methods of exposure may affect how the body processes the chemical — and therefore how BPA affects the body. The report concludes that there is “some concern” about the adverse health effects of BPA in fetuses, infants and children. “Some concern” is the third level on a scale of 5; “negligible concern” is the lowest level, while “serious concern” is highest. Even though the evidence isn’t conclusive about BPA’s link to cancer or other problems, Michael Thun, the American Cancer Society’s vice president of Epidemiology and Surveillance Research, says limiting exposure is “prudent.” For those who are concerned about BPA exposure, the US National Institute of Environmental Health Sciences recommends these steps: ? Don’t microwave polycarbonate plastic food containers. Polycarbonate is strong and durable, but over time it may break down from over use at high temperatures. ? Polycarbonate containers that contain BPA usually have a #7 on the bottom. ? Reduce your use of canned foods. ? When possible, opt for glass, porcelain or stainless steel containers, particularly for hot food or liquids. ? Use baby bottles that are BPA free.
July 20, 2010
The health effects of BPA is still in investigation
Investigation on harm of BPA towards human body
Bisphenol A (BPA), a compound in hard, clear polycarbonate plastics, is getting official scrutiny—and things are looking less than rosy for the controversial chemical. The U.S. government’s National Toxicology Program yesterday agreed with a scientific panel that recently expressed concern about physiological changes that occur in people when they ingest BPA that has leached from plastics into their food. The Canadian government is even considering declaring the chemical toxic. This could set the stage for banning it from plastic baby bottles, water bottles, and food containers. At the very least, some people will be even more eager to buy foods and beverages in BPA-free containers.
BPA has raised concerns because it appears to mimic the effects of estrogen, interfering with hormone levels and cell signaling systems. Previous studies have shown that people exposed to high levels of BPA have a greater risk of developing uterine fibroids, breast cancer, decreased sperm counts, and prostate cancer. Babies and children are thought to be at greatest risk from the exposure. In fact, the scientific evidence warrants “a higher level of concern than those expressed by the expert [scientific] panel for possible effects of bisphenol A on prostate gland, mammary gland and early onset of puberty in exposed fetuses, infants and children,” the NTP report concludes.
Not surprisingly, sales of BPA-free baby bottles spiked after yesterday’s news. “We tripled our sales overnight on the website and will be shipping an additional 300,000 bottles to Canada this week to meet an increased demand,” says Ron Vigdor, president of BornFree, which manufactures BPA-free bottles. He adds that Babies “R” Us also indicated that it would be increasing its order to U.S. stores.
Beyond switching baby bottles, another way to lower exposure to BPA is to avoid heating foods and liquids in plastic containers that contain the compound. The amount of BPA that leaches out, the NTP says, may depend more on the temperature of the liquid, food, or container itself than on the age of the plastic bottle or dish. So when it comes to Bisphenol A (BPA) exposure from polycarbonate plastic bottles, it’s not whether the container is new or old but the liquid’s temperature that has the most impact on how much BPA is released, according to University of Cincinnati (UC) scientists. Scott Belcher, PhD, and his team found when the same new and used polycarbonate drinking bottles were exposed to boiling hot water, BPA, an environmental estrogen, was released 55 times more rapidly than before exposure to hot water.
“Previous studies have shown that if you repeatedly scrub, dish-wash and boil polycarbonate baby bottles, they release BPA. That tells us that BPA can migrate from various polycarbonate plastics,” explains Belcher, UC associate professor of pharmacology and cell biophysics and corresponding study author. “But we wanted to know if ‘normal’ use caused increased release from something that we all use, and to identify what was the most important factor that impacts release.”
Belcher stresses that it is still unclear what level of BPA is harmful to humans. He urges consumers to think about how cumulative environmental exposures might harm their health.
“BPA is just one of many estrogen-like chemicals people are exposed to, and scientists are still trying to figure out how these endocrine disruptors–including natural phyto-estrogens from soy which are often considered healthy–collectively impact human health,” he says. “But a growing body of scientific evidence suggests it might be at the cost of your health.”
The UC team reports its findings in the Jan. 30, 2008 issue of the journal Toxicology Letters. UC graduate student Hoa Le and summer undergraduate research fellows Emily Carlson and Jason Chua also participated in this study, which was funded by a National Institute of Environmental Health Sciences grant.
July 15, 2010
plastic chemical danger
There’s a poignant scene in the film The Shawshank Redemption where an old prisoner is set free into a world that hardly resembles the one he left behind. Automobiles whiz past him as he tries to cross the street. His parole appointed job is at a fast paced market unlike any small town grocery store from his youth. It seems the whole world got in a great big hurry while he was away and he doesn’t like one bit. The speed of modern life is ever increasing. It’s hard to say how exactly this trend started. But it’s safe to say that at this point it’s driven primarily by consumer demand. A large enough segment of the population wants products and services that bring convenience home and streamline the many details that make up daily living.
In the 21st century, it’s hard to imagine a world in which plastic wouldn’t play a major role. After all, we drink from plastic bottles and wash our hair with shampoo that comes in similar looking containers. Our cars, phones, sunglasses and even the keyboards we type on are all made of this chemical compound. We are surrounded by plastic and what’s more, we’re happily hooked on it. That’s all good and well except for one thing: it may be harming us in unexpected ways. Today I’m going to focus on some recent findings on how chemicals in plastic may be altering the physiology and psychology of children throughout the world.
ADHD Linked to Phthalates
Phthalates are a variety of chemicals used to make plastic more flexible. They are commonly found in plastic wraps that are used to cover foods such as cheeses, meats and vegetables. But phthalates can also be present in cleaning items, personal care products, tubing and, most disturbingly, in toys. Many animal studies and some human studies have linked these specific elements to a variety of health conditions ranging from asthma to autism to birth defects to hormonal abnormalities and even obesity. Now, a new Korean trial has found a troubling association between phthalate concentrations and attention deficit hyperactivity disorder (ADHD) in children between the ages of 8-11. Urine tests were used to quantify the levels of this chemical in a group of 261 boys and girls. Those with the largest amounts of phthalates exhibited the most pronounced ADHD symptoms based on computerized tests and teacher reports that measured attention and impulsivity. The findings were described as presenting a “strong association between phthalate metabolites in urine and symptoms of ADHD”.
Boys Won’t Be Boys
A trial recently published in the International Journal of Andrology examined a proposed connection between elevated levels of phthalates in mothers’ prenatal urine and its subsequent affects on masculinity in preschool aged boys. A total of 145 children (aged 3.5 – 6.5) were included in this examination. Mothers who had higher prenatal levels of two phthalate metabolites (DBP and DEHP) generally had sons who exhibited less “male-typical behavior” such as fighting/”horsing around” and playing with trucks. The lead researcher of the study, Dr. Shanna H. Swan, theorized that phthalates may affect testosterone levels during a critical stage of male development in which sexual identity is formed. Previous studies have demonstrated a so called “phthalate syndrome” in male animals and boys which manifests in abnormal genital development.
Bisphenol A and Aggression in Girls
Bisphenol A (BPA) is another hormone disrupting chemical generally found in hard plastic products such as baby and water bottles, canned food linings and medical tubes. A report in the December issue of the journal Environmental Health Perspectives raises alarm about the effect of BPA in young girls. The source of BPA in these developing children is once again believed to be related to either prenatal exposure or a common environmental source that both mother and child share. A group of scientists examined prenatal urine samples from 249 women and compared them to the behavioral patterns of their related children. The mothers with the highest concentrations of BPA were more likely to have girls who were more aggressive and hyperactive at the age of 2 as compared to mothers with lower levels of BPA. One of the researchers commented that “girls whose mothers had higher BPA exposure were more likely to act like boys than girls”.
Dr. Andrew Weil, a leader in the field of alternative and complementary medicine, offers some sage advice about how to lower BPA and phthalate exposure for adults and children alike in his Fall 2009 Healthy Eating Guide. Dr. Weil suggests: a) cooking and microwaving only in ceramic or glass containers; b) opting for BPA-free baby bottles and stainless steel water bottles; c) avoiding the use of plastic wrap and placing plastic-wrapped market items in more suitable containers (glass) once at home and; d) choosing packaged foods and oils in glass bottles rather than plastic bottles or lined cans.
There’s no turning back the clock or putting the genie back in its lamp. Plastic is here to stay, at least for the foreseeable future. But we do have options about how and when you we choose to use it. A good place to begin your plastic transformation is at home. Avoiding BPA and phthalates outside of your abode can be more challenging. When you’re out and about, the key is to simply make the best choices that are available to you. Another way to promote change in this arena is to purchase products that specifically avoid the use of such questionable chemicals. You’ll often find that manufacturers will mention this on product labels or in the accompanying literature because it can be a selling point to informed consumers. In the same way that we the people have demanded a more convenient and speedier world, we too can demand a safer place for our current and future generations.
July 8, 2010
Shocking! White Trash Threaten Earth’s Oceans
Plastics have been around for, perhaps less than 100 years. So in the short span, there hasn’t been a group of microorganisms who have evolved who are capable of biodegrading plastics.
Scripps Institution of Oceanography in San Diego USA had taken a investigation and found that the area of Pacific Plastic Garbage Patch that lies between California and Hawaii is double of that of Texas.
Researchers said: “Unfortunately, there are a lot of plastic in oceans, Just one year, the Japan Coast will gather approx.150,000 tons of plastic debris”. In a sense, you are placing all these plastics in the ocean, and eventually they will reach the deep ocean environment.
The increasing quantity of plastic now known to be in the oceans, plastic lasts a long time there, because cold sea water slows down the chemical reactions that cause a plastic bottle lying on a beach, for example, to break down.
It seemed that it is not the most terrible thing that the plastic gathered in oceans, there is a new study found that plastic decomposition will cause more pollution. Plastics in ocean biodegrade slowly and the biodegradation of plastic occured in ocean will cause bigger damages.
“Plastic maybe biodegraded at an alarming rate under the action of rain, sun and other environmental factors,” said the researchers. At the same time, they will may also release toxins contained bisphenol A to the oceans, bisphenol A are be deemed to has effect on disrupting hormonal function of animals, and act on animal’s reproductive system.
But if you define biodegradation as the complete conversion of plastics into carbon dioxide and water, all the plastics that we ever put into the ocean – which is over the past 50 to 60 years – would still be there in the ocean. And we keep adding more and more to it. And we do not know what the ecological consequences of this are. They might be very serious.
Earth’s oceans are absorbing carbon dioxide from the atmosphere, making the oceans more acidic. This could pose a threat to ocean life.
Around the world there are signs that plastic pollution is becoming a serious pollution and is threatening and destructing the environment, more terrifying it has begun to filtrated into the whole food chain of the earth gradually.
To protect our common homeland, there is a lot of things we need to do!
