Bisphenol A Linked to Breast Cancer

Byoliveridley

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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    What's the matter with Canada?

    Byoliveridley

    But beneath the calm exterior, Canada’s political system is in turmoil. Since 2004, a succession of unstable minority governments has led to a constant campaign frenzy, brutalizing Canada’s once-broad political consensus and producing a series of policies at odds with the country’s socially liberal, fiscally conservative identity. Canada is quietly becoming a political basket case, and this latest election may make things even worse.

    What’s the matter with Canada? – By Christopher Flavelle – Slate Magazine

    I don’t necessarily agree with the whole “basket case” assertion, it is a fundamentally strong country with a broad consensus on what the country should be.

    The current set of political parties is rewarding a minority set of policies (the conservatives) by fragmenting the majority centre-left of centre consensus between 4 different political parties, none of which will talk to each other. This is not exactly new, the conservatives only merged their parties a few years back.

    The liberals suffer from Dion’s non Englishness, he gets little traction from the English media (no idea about the French, I don’t know any). He’s not that charismatic, nor does he orate well in English, and so like the American election, it is all optics. The liberals also seem to have no understanding of what it takes to win a modern election. The conservatives get in the news all the time, their ads are all over TV, the liberals seem to be MIA.

    Harper on the other hand is “strong”, strength of course being defined as sounding decisive and declaratory, even though he usually just sounds alarmist and hyperbolic all the time. Somehow, this is interpreted as leadership. I guess the only good quality of leadership is being loud.

    Dion also made a gamble by selling something called the Green Shift, a carbon tax, to increase efficiency in energy consumption and reduce greenhouse gas emissions. Even though the tax is designed to increase efficiency in a country notorious for its very poor efficiency (27th among the 29 OECD countries in energy use/capita), it is being demonized as a tax that will destroy the country (just like every other environmental regulation destroyed every other country). It is also bad timing, as energy prices have soared recently, and Canada’s economy sputters to a halt due to falling resource prices and the American housing market bust (destroyed the BC lumber industry). The last thing people want to hear is “tax”, even though the middle class will get more than sufficient rebates to cover any tax increases. The liberals seem to have overplayed this hand. Elections are never won on environmental issues, too easy to attack.

    The conservative pitch thus far has only been to attack Dion while offering some incremental changes. But as Harper is flirting with a majority, this Toronto Star editorial asks the right questions.

    While Harper is presenting himself as a kinder, gentler Conservative these days, in the past, as a Reform MP, head of the National Citizens’ Coalition and leader of the Canadian Alliance (successor party to Reform), he staked out quite radical positions. He has called Canada “a northern European welfare state in the worst sense of the term,” has denounced the “moral nihilism” of the Liberals and the left for opposing the Iraq war, has suggested building a “firewall” around Alberta, and has called for “market reforms” for health care, “further deregulation and privatization,” and “elimination of corporate subsidies.”

    With a Conservative majority in sight, it is fair for Canadians to ask Harper whether he still holds these views and would implement them once in office. And if the answer is No, Harper should use the remaining four weeks of this election campaign to tell voters just what he would do with a majority.

    The media lets Harper get away with sounding “presidential”, his proposals are very vague, and that is worrying. It is clear, however, that from an environmental standpoint, he will be a disaster. A combination of a slowing economy and reduced social support programs (conservatives hate safety nets for regular people) will be bad for the not so well off Canadians. We shall see what happens in a few weeks.

  • Benzene in Soft Drinks – Analytical Artifact?

    Byoliveridley

    An update on the benzene story from last month.

    Chemical & Engineering News: Latest News – Dispute Over Benzene In Drinks

    In late 2005, FDA began analyzing beverages containing benzoate and ascorbic acid. The majority of samples contained either no detectable benzene or levels below 5 ppb, says Robert E. Brackett, director of FDA’s Center for Food Safety & Applied Nutrition. FDA’s results are preliminary. After its survey is complete, the agency will determine what, if any, additional action is necessary, Brackett wrote to EWG. Changes in FDA’s analytical procedures may account for the differences in results. To collect benzene in the earlier tests, FDA used a purge-and-trap method, in which the samples were heated to 100 °C for 30 minutes. Recently, the agency has been using a static-headspace methodology, which does not involve much heat. In the earlier tests, the high heat was probably creating benzene, says an FDA source who asked not to be identified.

    The explanation seems to make sense. Low level analysis is riddled with instances such as these, where the analyte you’re looking for is  introduced into the sample after the fact. It is impossible to decide without looking at the protocol whether this happened or not. Since the source of the benzene is from the reaction of ascorbic acid (aka Vitamin C) and benzoate salts, notably sodium benzoate, it would have been clear to anyone doing the analysis to avoid conditions that would result in the formation of benzene during the analysis, or maybe not…

    Static Headspace analysis usually involves some heating as well, at much lower temperatures for shorter periods of time, though in the case of something as hydrophobic as benzene, not much heat would be required. So, the artifacts in static headspace would in this case be lower than in purge and trap analysis.

    Still not a concern in the grand scheme of aggregate benzene exposure.

  • Rally for Climate Change Tomorrow in your Neighbourhood

    Byoliveridley

    So, to draw attention to the need to dial CO2 emissions down to 350 ppm, 350.org is organizing a series of worldwide events. This one is in my neck of the woods and I plan to be there. Go to the website to find out where yours is and show up. You will be part of the world’s largest climate change rally, 4500 events in 173 countries. Who knows, you might meet an interesting person or two, or the love of your life :-0 (hey, it’s happened before!)

    Victoria350.org is a collaboration of numerous community groups who are coming together to host FutureFest Victoria, a celebration to raise awareness around the number 350. There will be a kids corner with crafts, an art-based community visioning space, main stage music, a flash dance mob, local non-profit and community business tables, organic produce and coffee, topped off with a 350 bike ride downtown. Bring the whole family and come down for a fun and meaningful afternoon. All are welcome!

    via FutureFest Victoria | 350.org.

    FYI, the Victoria event is at Centennial Square tomorrow from 12-4.

  • Today is World Water Day

    Byoliveridley

    World Water Day – World Water Day

    As opposed to every other day when water’s not all that important! But seriously, the site is a good compendium of resources. This year’s theme is coping with scarcity. I remember when Madras had severe water shortages in the late ’80s until a couple of years back. You had to be either very lucky to live in the right neighborhood/rich enough to buy water from private tankers to fill up your water tank. Running water was off and on, we had giant buckets of stored water, it was quite an adventure for me (and a great deal of stress for my parents, of course). Those days still leave a big impression on me. Everytime I leave the tap running for more than 30 seconds, or stand in the shower for longer than necessary, I can hear my mom yelling!

  • Nissan goes electric

    Byoliveridley

    Nissan Shows Off Its Electric Car, the Leaf – NYTimes.com

    What, no Canada? But still,  an electric hatchback, hits all my buttons and dings all my dongs! I only hope to keep my current, explosion powered hatchback long enough to not buy one ever again. Price, of course, will be a consideration. The good news is that Nissan is considering leasing the battery instead of people having to buy it up front, a great idea, not as great as the battery instant replace model from Shai Agassi and Better Place, but one that lessens the battery buying burden.

    The future is electric.

  • BC and Carbon

    Byoliveridley

    As BC’s Carbon Tax enters the terrible twos, and is the subject of stupid headlines in the CBC trumpeting a 1.5c/L increase in gasoline price (smaller than the price difference between a pump in the Saanich Peninsula and outside), it is worthwhile to see what the rest of the province’s carbon strategy is, or isn’t doing.

    Metro – B.C. looks to carbon capture to balance clean-air targets with energy revenues

    Economic realities and environmental promises are creating an explosive mixture for the recession-fighting B.C. government as it juggles expansion in its oil and gas industry with the need to cut greenhouse gases.

    Massive untapped gas fields in northeastern British Columbia hold billions in potential revenues, but environmentalists are watching to see if Premier Gordon Campbell will stick to his promise to fight global warming by cutting emissions by one-third by 2020.

    This is one of the issues with relying solely on a carbon tax to reduce GHG emissions, it is inadequate. A carbon tax is a consumption tax levied at the point of sale, not at the point of production. The BC government has gotten a lot of positive press for the carbon tax, but it is reliant on natural gas and oil to bring in some revenue. After all, the lumber industry is dying with the US housing bust, and something needs to get the province out of deficit as the BC government will not countenance any tax increases whatsoever.

    The weakness of the province’s carbon plan is best typified by quotes from a couple of fossil fuel executives/government officials:

    “The question is, if I were to make this big investment, who’s going to pay me to do that so I can generate a return for my shareholders? Weilinger asks.

    Horne agrees there is no business case for oil and gas companies to justify carbon capture projects to shareholders, but says industry needs to support greenhouse gas reductions.

    The notion that industry will somehow support reductions is hilariously disingenuous. Carbon capture and storage is an untested and expensive technology even when it comes to sources where all the CO2 comes out of one tailpipe, like a power plant. The notion that it can be used in an activity as widespread and diffuse as oil/gas drilling is laughable. The best way for these companies can be forced to make their mining more GHG emission friendly is to price their actions according to their GHG production footprint, something a differently designed carbon price would do.

    BC’s carbon tax, in my book, was a shrewdly designed political maneuver to undercut traditional environmentalist support for the opposition NDP, which very “smartly” took the bait and campaigned against it in a recent election earning howls of disgust from the mainstream environmental movement.

    When it actually comes to cleaning up and taking actions that will actually reduce the province’s GHG footprint, the government is found wanting, as expected.