Bisphenol A Linked to Breast Cancer

Chemical & Engineering News: Latest News – Bisphenol A May Trigger Human Breast Cancer

Soto and her colleagues exposed pregnant rats to bisphenol A at doses ranging from 2.5 to 1,000 µg per kg of body weight per day. By the time the pups exposed at the lowest dose reached the equivalent of puberty (50 days old), about 25% of their mammary ducts had precancerous lesions, a proportion three to four times higher than among the nonexposed controls. Mammary ducts from all other exposure groups showed elevated levels of lesions. Cancerous lesions were found in the mammary glands of one-third of the rats exposed to 250 µg/kg/day.

Bisphenol A is used in the manufacture of polycarbonate plastics and epoxy resins. It is found in many food and beverage containers, including baby bottles. It is also found in canned food linings and dental composites, and it leaches from all of these products. In one study, Soto notes, urine samples from 95% of the human subjects contained the chemical.

The Environmental Protection Agency has set a safe human intake dose of 50 µg/kg/day for bisphenol A. “On the basis of the effects observed in recent studies, this seems to be an unsafe level,” Soto says.

Bisphenol A is old news, BTW, people have known for a while about this chemical’s propensity to carcinogenicity. Of course, there’s that whole argument about pregnant mice being more susceptible to chemicals than humans, etc. So, the jury is still out. but Soto is right, 50 µg/kg/day seems to not provide enough of a safety factor. The EU uses 10 µg/kg/day, though they do say that

realistic worst-case estimates of consumer exposure via foodstuffs, range from 0.00048 mg/kg bw/day for adults to 0.0016 mg/kg bw/day for infants, which is well below the maximum exposure level

Of course, who knows what additive effects this chemical may have with the multitude of other chemicals floating around. Doing tests of single chemicals and trying to link that to epidemiological data is a perilous undertaking, the connections are tenuous most of the time and the plastics companies routinely fund studies that prove otherwise, because as you know, if you know what you’re going to find before you study it, you will find it!

Read the wikipedia stub on polycarbonates. Us yuppies who drink religiously from Nalgene bottles to avoid phthalates and nasty tastes would do good to take note! I guess glass is the best, though it does have that annoying tendency to shatter when dropped… Water from glass bottles do have the best taste, though.

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    The Canadian Medical Association Journal is denouncing the federal government for what it expects will be Canada's continued efforts to block international controls on asbestos at UN-sponsored negotiations next week.

    A strongly worded editorial, appearing in tomorrow's issue of the journal, says the government "knows what it is doing is shameful and wrong" and compared Ottawa's moral stature in continuing to promote the use of the cancer-causing material to that of arms traders.

    The negotiations, known as the Rotterdam Convention, are to start Oct. 27 in Rome. The focus of the talks will be on whether to add the chrysotile variety of asbestos to the world's list of most dangerous substances. Once a substance is listed, countries must give prior informed consent that they know they are buying a highly dangerous material before being allowed to accept any imports.

    via globeandmail.com: Medical journal blasts Ottawa for promoting asbestos abroad

    Canada’s national shame, its export of a killer product not used by Canadians to developing countries where the safeguards it insists on for the ‘safe” use of this product can’t possibly be carried out or enforced. For god’s sake, it’s 700 jobs, and people who can be retrained to do something that does not kill people.

  • Oil refineries underestimate release of emissions, study says

    A study by the Alberta Research Council that investigated the plume of contaminants emanating from a Canadian oil refinery using high-tech sniffing equipment found the facility dramatically underestimated its releases of dangerous air pollutants.The refinery, which wasn’t identified but is believed to be in Alberta, released 19 times more cancer-causing benzene than it reported under Environment Canada disclosure regulations, about 15 times more smog-causing volatile organic compounds, and nine times more methane, a greenhouse gas, according to the study.The testing is believed to be the first at a North American refinery using the sophisticated technology relying on lasers, and is considered state-of-the art. The technology, developed by British Petroleum, has been in widespread use in Europe for nearly two decades.

    globeandmail.com: Oil refineries underestimate release of emissions, study says

    Serious stuff, this. As the report points out, this is old news, here’s a workshop report from the EPA last year about this very issue (no, don’t read it, 303 pages long). Volatile organic compounds are inputs into air pollution models that measure ozone levels. When your local agency tells you that Tuesday is going to be a code orange ozone day, they rely on ozone models such as CMAQ. Now, without proper inputs, you are going to make some serious errors in prediction. These errors are somewhat mitigated by the tuning of these models with measured concentrations. So, there is some error compensation going on within the model.

    More importantly, by underestimating fugitive emissions, refineries can reduce their leak monitoring, reporting and mitigation costs. There is also the issue of conflict of interest here. The current technique was developed by the American Petroleum Institute!

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    Coffee Roasting and Popcorn Lung

    Cross-posted from Interrobang

    Who among us coffee drinkers don’t love the smell of freshly roasted coffee? I am sure some of us imagine how much fun it would be to smell freshly roasting coffee more often. I don’t, because smell for me is an instant jolt of pleasure/pain followed by a rather rapid decline into the background.

    Caution, though. New measurements from the US Centres for Disease Control warn of high exposure to some pretty nasty chemicals that can cause your lungs to be destroyed irreversibly, the unfortunately named “popcorn lung” or bronchitis obliterans:

    Investigators with the National Institute of Occupational Safety and Health, a research arm of the CDC, spent several days at Madison-based Just Coffee in July. Investigators tested personal air space and took air samples to measure the concentration of the chemicals diacetyl and 2,3-pentanedione… NIOSH researchers found levels in three breathing-zone samples that exceeded the safety levels recommended by the CDC.

    Coffee Roasting Plants and Exposure

    The test results show a marginal exceedance in this case, but noted that ventilation is a big factor and these tests were done under well ventilated conditions on a warm and dry day when doors were open. So, exposure can be higher in other circumstances.

    Worker exposures are to higher levels, and are more sustained, so they deserve the most attention.

    So, local coffee roasters, it may make sense to confirm that your roasting environments are not exposing your workers to harmful, lung obliterating chemicals. Remember, organic, shade grown, fair pay, artisanal roasting aside, chemical exposures to workers don’t change. And, everything that smells good isn’t good for you.

    One of my frequent points of emphasis (rants, some might say) is on the relative risk vs. media attention to exposures of people to ambient, day to day concentrations of potential harmful chemicals vs. those faced by workers everywhere. The last time diacetyl and bronchitis obliterans were in the news, it was around the use of diacetyl to produce that buttery smell so beloved in microwave bag popcorn (I don’t like it myself, olive oil all the way!). Despite reports of many workers facing severe lung issues, it took the detection of the disease of one person eating multiple bags of microwave popcorn over many years to actually move government regulators into action on diacetyl. People who work in factories, in the fields, and make things are exposed to thousands of times higher concentrations of harmful chemicals for longer periods of time, but their concerns are often de-emphasized.

    This doesn’t mean ambient exposures in the general population are to be ignored, but worker exposures are to higher levels, and more sustained, so they deserve the most attention.

    16-May-2016 Update

    This US Centers for Disease Control page is a good collection of information and further readings. They recommend facility tests to measure diacetyl and its cousin 2,3-pentanedione, and better ventilation, worker safeguards and personal protective equipment as necessary. They also note that at least five workers in large scale coffee processing plants have been diagnosed with bronchitis obliterans.

    Coffee image By Ailura – Own work, CC BY-SA 3.0

  • James Hansen disses the Tar Sands

    James Hansen: Obama’s Canada trip defines our critical carbon moment | Comment is free | guardian.co.uk

    The tar sands of Canada constitute one of our planet’s greatest threats. They are a double-barrelled threat. First, producing oil from tar sands emits two-to-three times the global warming pollution of conventional oil. But the process also diminishes one of the best carbon-reduction tools on the planet: Canada’s Boreal Forest.

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    Colonialism: Environmental Edition

    Does put recycling in context…

    Independent Online Edition > Environment

    Regardless of how carefully you separate your waste, there is a good chance a disposal firm will dump it all in together with other kinds of plastic trash and ship it to the developing world to be dealt with by a family of migrant workers earning a pittance. They will deal with the salad-bar container, the pistachio ice-cream container and the superfluous bag for carrots in your shopping basket in a variety of different ways – it may be recycled, it may become landfill or it may simply be burnt. Whatever happens, it is generally not a priority for the waste disposal company. Britain dumps around two million tonnes of waste in China every year, everything from plastic mineral water bottles to shopping bags and other forms of superfluous packaging from some of the country’s biggest supermarkets.

    Same for India as well. The article says that all of this “recycling” is illegal. But how do you hide 200,000 tonnes of plastic waste?

    Read the whole article, it is tragic. Some highlights:

    So too are the many and varied health complaints suffered by the local population, who risk multiple skin ailments and exposure to potent carcinogens as they touch the contaminated materials. Poisonous chemical effluents stream into their water supply, turning it black or lurid red, and studies by Greenpeace show that acid rain is the norm in this region. Children are prone to fevers and coughs. Their skin is often disfigured by the toxic plastic waste they have to process.

    A report by the University of Shantou on the town of Guiyu, another Guangdong recycling hub, showed that more than 80 per cent of local children suffer from lead poisoning.