PCBs love to sorb to oil

Byoliveridley

News of possible interest only to me. It seems obvious that oil present in sediment enhances sorption and storage of PCBs than soot/black carbon. After all, it is a liquid phase and is present in higher amounts than black carbon. PCBs are so hydrophobic that almost any organic material has a higher affinity for PCBs than water/sediment. Carbon is a strong PCB adsorbent only for planar PCBs, and then only if it is itself graphitic, hence planar. In all other cases, oil should outcompete  carbon for PCBs. Glad they found experimental evidence. In all my (three) years of analyzing for PCBs, the oily samples are always the highest concentration ones.

Oil Is a Sedimentary Supersorbent for Polychlorinated Biphenyls

Oil Is a Sedimentary Supersorbent for Polychlorinated Biphenyls

Michiel T. O. Jonker and Arjan Barendregt

Institute for Risk Assessment Sciences, Utrecht University, P.O. Box 80176, 3508 TD Utrecht, The Netherlands

Received for review January 18, 2006

Revised manuscript received April 10, 2006

Accepted April 11, 2006

Abstract:

The often-observed enhanced sorption of hydrophobic organic chemicals (HOCs) to sediments is frequently attributed to the presence of soot and soot-like materials. However, sediments may contain other hydrophobic phases, such as weathered oil residues. Previous experiments have shown that these residues can be efficient sorbents for certain PAHs. In this study we investigated sorption of PCBs to sediments contaminated with different concentrations and types of oils, and from that derived oil-water distribution coefficients (Koil). Sorption of PCBs to both fresh and weathered oils was proportional to sorbate hydrophobicity, and no effects of PCB planarity were observed. Furthermore, the experiments demonstrated that different oils sorbed PCBs similarly and extensively (Koil up to 108.3 for PCB 169), and that weathering caused an almost 2-fold increase in sorption of the lower chlorinated PCBs. Koil values indicated that at the PCB equilibrium concentrations tested (pg-ng/L range), for many congeners weathered oil is a stronger sorbent than pure soot and soot-like materials. Due to attenuation of adsorption to the latter materials in sediments (caused by competitive adsorption with organic matter), sedimentary weathered oil will therefore, if present as a separate phase, defeat sedimentary soot, coal, and charcoal as PCB sorbent in most cases. Consequently, weathered oil probably is the ultimate sedimentary sorbent for PCBs and should be included in HOC fate models.

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    Vote Strategically for the Environment

    Byoliveridley

    via Vote For Environment / Voter Pour l’Environnement.

    This site wants you to vote strategically to avoid splitting the anti-conservative vote on the assumption that all things being equal, the conservatives are much worse for the environment than any of the other parties. This is not really how you want an election to be decided, but a party that represents the minority of Canadians should not get a parliamentary majority simply because of a flawed voting system.

    I would heartily endorse a preferential ballot system for us. How does this work?

    Instant-runoff voting (IRV) is a voting system used for single-winner elections in which voters have one vote and rank candidates in order of preference. If no candidate receives a majority of first preference rankings, the candidate with the fewest number of votes is eliminated and that candidate’s votes redistributed to the voters’ next preferences among the remaining candidates. This process is repeated until one candidate has a majority of votes among candidates not eliminated. The term “instant runoff” is used because IRV is said to simulate a series of run-off elections tallied in rounds, as in an exhaustive ballot election.

    Under this system, if you like the Green Party the best because of their environmental policies, but know they cannot win, you can still vote for them. Just have the liberals/NDP as the second choice. It is overwhelmingly likely that if you like the Green Party policies, you like the policies of the conservatives more than the policies of the liberals or the NDP. With our current system, that’s exactly what your vote will say. Your vote for a Green Party candidate in this election is essentially a vote for the Conservatives.

    In the absence of the preferential ballot, or instant runoff voting, using web 2.0 methods to vote strategically is the next best thing, and a great idea!

  • Powerful Story of Environmental Racism

    Byoliveridley

    I have nothing to say, just read and weep.

    A Well of Pain – washingtonpost.com

    She has had cervical polyps. Another of her daughters, Holt-Orsted’s sister, has had colon polyps. Three of Holt-Orsted’s cousins have had cancer. Her aunt next door has had cancer. Her aunt across the street has had chemotherapy for a bone disease. Her uncle died of Hodgkin’s disease. Her daughter, 12-year-old Jasmine, has a speech defect.

    They believe trichloroethylene, or TCE, is to blame for it all. The carcinogen leaked from the county landfill, just 500 feet away, and contaminated the Holts’ well water. That fact is undisputed. For years, the family drank that water, bathed in that water, cooked in that water — and had no clue that it might harm them.

    More…

    In that box, she found letters and documents indicating that Tennessee environmental and water officials had concerns about the possibility of TCE appearing in the Holt’s well water as early as 1988. The Holts’ well was left untested for nine years while TCE problems in the wells of white families were tended to with haste, the records showed.

    Even more…

    Meanwhile, the toxin also showed up at high levels in a spring and several wells in 1993 and 1994. The white families at those sites were immediately told to stop using the water. And tests were conducted repeatedly all around the landfill — but not at the Holt well.

  • British Columbia Introduces a Carbon Tax

    Byoliveridley

    Wow, I am already proud of my future destination, a carbon tax, no less. One that will start off at $10 per tonne of carbon (2.4c per litre of gasoline, or about 9c a gallon) and rise by a factor of three in a few years…

    VICTORIA – Finance Minister Carole Taylor introduced an escalating carbon tax on most fossil fuels Tuesday, one she says recycles revenues back to taxpayers and businesses and is designed to ignite an environmental social movement in British Columbia and across Canada to fight climate change.And she’s handing every British Columbian $100 in June as seed money to get them thinking green.

    The Canadian Press: BC introduces carbon tax, but off-sets increased fuel costs with tax cuts

    The carbon tax advocacy center sets the required starter tax as 10c a gallon, BTW, so this measure by BC is no joke, it’s a serious effort to rein in CO2 emissions from the province. Carbon taxes are in general regressive as they are flat taxes, so the poor pay the same as the rich, but obviously will suffer more. So, what is the BC government doing to ensure that the poor don’t suffer?

    The carbon tax revenue, estimated to hit $1.8 billion over three years, will be returned to taxpayers through personal income tax and business tax cuts, she said.The government will introduce legislation that requires it to table an annual plan that shows how the carbon tax revenue will be returned to taxpayers, Taylor said

    Good words. But Taylor needs to realize that in the absence of well designed tax offsets, the people and businesses of BC will be at a temporary competitive disadvantage. It’s tricky to be an early adopter, but I am optimistic that BC will be the better for it.

    Wonderful, now the rest of Canada (and the US) needs to follow suit. And, I look forward to blogging about Canada already, exciting!

    Thanks of course to the grist for alerting me…

    Update: An economist allays my regressivity and harm to business fears…

    Blogged with Flock

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    Canada to stop asbestos mining and stop defending it.

    Byoliveridley

    Canada’s long and sorry saga of exporting death (asbestos) and defending it loudly and proudly in international fora is over and I needed to mark this happy day on the blog. The newly elected provincial government in Quebec, the Parti Quebecois have followed through on their campaign promise to finally end this small “industry” employing a few workers. Canada will no longer produce asbestos, or fight the listing of asbestos as a toxic substance.

    It is going to take $50 million in government funds, a fraction of the cost of one fighter jet, to transition the workers away (if they get the money, not the mine owners). That’s it, why were we exporting death to India and other countries for this, I don’t know.

    Canada’s many conservative and liberal governments fought hard for years to preserve the industry, using techniques lifted from tobacco propaganda, or today’s climate change challenges. I leave you with the ruling Canadian government’s response: Finely tuned to appeal to everyone who likes mesothelioma, cancer and death.

    “Mrs. Marois’s decision to prohibit chrysotile mining in Quebec will have a negative impact on the future prosperity of the area,” (Industry Minister) Mr. Paradis said in a statement.

    That about sums it up. But, it is a good day for public health, nevertheless.

    Citing PQ pressure, Canada to cease defending asbestos mining – The Globe and Mail.

    Featured image courtesy wikipedia used under a Creative Commons license (a micrograph of asbestos fibres causing lesions in the lung).

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    Opinion Polls and Yes Prime Minister

    Byoliveridley

    This story from the grist about a push poll arranged by Rasmussen showing 67% support for the reinstatement of offshore oil drilling in the United States reminded me of this most delightful exchange from Yes Prime Minister, still one of my all time favourite television shows and one that taught me almost everything I needed to know about parliamentary politics at a tender age. The show is about British politics through the eyes of an earnest but bumbling politician, his very experienced bureaucratic handler and his secretary with divided loyalties. The show is incredibly insightful and funny at the same time. But, before I get to my favourite part, some background…

    It’s that time of the year when the republicans want to enrich their oil buddies by opening up oil drilling offshore of the U.S. This year, the high price of gas provides a convenient excuse and rallying point. After all, who wouldn’t want to pay less for gas. Of course, a U.S government study done by the Energy Information Administration in 2007 indicates that at best, you would see a 3% increase in production by 2030, and we all know how much that would affect gasoline prices this summer. Yet, here’s the first question from the “poll”

    In order to reduce the price of gas, should drilling be allowed in offshore oil wells off the coasts of California, Florida, and other states

    No really, what are you supposed to say? Can such reputable firms lie to you like that? Anyway, Joseph Romm from the original gristmill post breaks it down completely so I don’t have to. but after reading his post, come back and read the following exchange from Yes Prime Minister, and do listen to the actual audio clip from the show.

    Yes Prime Minister – Season 1Episode 2 (warning: Strangely formatted website)

    Sir Humphrey: “You know what happens: nice young lady comes up to you. Obviously you want to create a good impression, you don’t want to look a fool, do you? So she starts asking you some questions: Mr. Woolley, are you worried about the number of young people without jobs?”

    Bernard Woolley: “Yes”

    Sir Humphrey: “Are you worried about the rise in crime among teenagers?”

    Bernard Woolley: “Yes”

    Sir Humphrey: “Do you think there is a lack of discipline in our Comprehensive schools?”

    Bernard Woolley: “Yes”

    Sir Humphrey: “Do you think young people welcome some authority and leadership in their lives?”

    Bernard Woolley: “Yes”

    Sir Humphrey: “Do you think they respond to a challenge?”

    Bernard Woolley: “Yes”

    Sir Humphrey: “Would you be in favour of reintroducing National Service?”

    Bernard Woolley: “Oh…well, I suppose I might be.”

    Sir Humphrey: “Yes or no?”

    Bernard Woolley: “Yes”

    Sir Humphrey: “Of course you would, Bernard. After all you told you can’t say no to that. So they don’t mention the first five questions and they publish the last one.”

    Bernard Woolley: “Is that really what they do?”

    Sir Humphrey: “Well, not the reputable ones no, but there aren’t many of those. So alternatively the young lady can get the opposite result.”

    Bernard Woolley: “How?”

    Sir Humphrey: “Mr. Woolley, are you worried about the danger of war?”

    Bernard Woolley: “Yes”

    Sir Humphrey: “Are you worried about the growth of armaments?”

    Bernard Woolley: “Yes”

    Sir Humphrey: “Do you think there is a danger in giving young people guns and teaching them how to kill?”

    Bernard Woolley: “Yes”Sir Humphrey: “Do you think it is wrong to force people to take up arms against their will?”

    Bernard Woolley: “Yes”

    Sir Humphrey: “Would you oppose the reintroduction of National Service?”

    Bernard Woolley: “Yes”

    Sir Humphrey: “There you are, you see Bernard. The perfect balanced sample.”

    That is what I think about opinion polls!