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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  • Climate change infographic

    Byoliveridley

    This infographic came my way via Learnstuff and it looked interesting. I have a love-hate relationship with infographics and this one evokes the same feelings of “I really appreciate the effort someone put into this and it looks great” vs. “how is this going to influence our policy makers, or create the intensity (read this link, it’s really good stuff by David Roberts of Grist) that is required to foster the system change we need”?

    Climate-Change

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    Lead and Crime

    Byoliveridley

    leadcrime.jpg

    The next time Giuliani tries to take credit for the decrease in violence during his tenure as NYC’s mayor, send him this chart.

    The NY Times shines some light on Jessica Reyes’ excellent work linking decreased lead exposure to a drop in violent crime in the US. The decreased lead exposure, of course, was from the phase-out of leaded gasoline from the American market. BTW, Nascar still uses leaded gasoline in its cars, nice going, guys.

    The answer, according to Jessica Wolpaw Reyes, an economist at Amherst College, lies in the cleanup of a toxic chemical that affected nearly everyone in the United States for most of the last century. After moving out of an old townhouse in Boston when her first child was born in 2000, Reyes started looking into the effects of lead poisoning. She learned that even low levels of lead can cause brain damage that makes children less intelligent and, in some cases, more impulsive and aggressive (Emphasis Added).

    Lead exposure at an early age (2-3 years) is especially significant as this is an age where personality development occurs and any interference in neuron development and apoptosis (death!) can cause permanent changes in personality. This excellent review article summarizes the effects of lead on neuronal development.

    Reyes’ research mentions that while decreased lead exposure was very well correlated with violent crime (accounting for 56% of the reduction in crime), no correlation was found to property crimes (such as theft). This of course makes intuitive sense. A property crime is usually premeditated whereas violence is usually impulsive (excluding serial killers, of course). It is more likely that a budding criminal sets out to steal a car than to beat somebody to pulp. It is when the crime goes wrong that the probability of a violent crime increases. An individual with damaged impulse control is then more likely to seek a violent way out of the bad situation.

    Our society (like most) views violent crime as a moral issue, a matter of good and evil that is determined by your “character”. So, a simple chemical correlator to violent crime that can explain a majority of the commission of violent acts goes a long way in undermining this whole notion of morality and crime. Of course, there are other sociological factors at play which need to be addressed. But it is heartening to know that beyond all the complicated and recalcitrant social issues that underly crime, there’s a ubiquitously evil pollutant lurking that can be eliminated. I am guessing that this line of reasoning is not going to be very popular among the “tough on crime” types that perpetrate our political airwaves these days.

    Reference

    Reyes, Jessica Wolpaw (2007) “Environmental Policy as Social Policy? The Impact of Childhood Lead Exposure on Crime,” The B.E. Journal of Economic Analysis & Policy: Vol. 7 : Iss. 1 (Contributions), Article 51.

  • BC Carbon Tax regressive?

    Byoliveridley

    British Columbians with low incomes will benefit from the carbon tax in its first year, but will pay more by the scheme’s third year, a new study concludes.

    The impact of the tax and its offsetting income tax cuts will become increasingly unequal unless the provincial government increases payments to low-income earners, the study says.

    The study, by Marc Lee, senior economist with the Canadian Centre for Policy Alternatives, and Toby Sanger, senior economist with the Canadian Union of Public Employees, takes a detailed look at the fairness of the controversial tax.

    via Carbon Tax Whacks the Poor, Later :: News :: thetyee.ca

    The report makes some good points. Revenue neutrality (the offsetting of carbon taxes with income/corporate tax cuts) has nothing to do with reducing carbon emissions. If I were to redesign this tax, I would do as the report says, increase rebates to lower income people, reduce corporate tax cuts so that the resulting revenue can be used to fund more transit infrastructure, energy efficiency infrastructure and the building of a low carbon economy.

    A carbon tax in itself is not sufficient to reduce emissions. It does its part, but building an energy efficient, low carbon infrastructure will do a lot more and the money’s there, just use it.

    You can read the whole report here.

  • Corn Can't Solve Our Problem – washingtonpost.com

    Byoliveridley

    A must read for anyone who likes articulate scientists writing very approachable articles about important subjects!
    Corn Can’t Solve Our Problem – washingtonpost.com

    If every one of the 70 million acres on which corn was grown in 2006 was used for ethanol, the amount produced would displace only 12 percent of the U.S. gasoline market. Moreover, the “new” (non-fossil) energy gained would be very small — just 2.4 percent of the market. Car tune-ups and proper tire air pressure would save more energy.

    Proper tire pressure is not sexy, and does not lead to billions of dollars of profits!

    The net effect is that ethanol from corn grown in the Corn Belt does increase atmospheric greenhouse gases, and this increase is only about 15 percent less than the increase caused by an equivalent amount of gasoline

    Corn is such a boondongle, it’s amazing what the ADMs and Monsantos of the world can do.

    This means that when tropical woodland is cleared to produce sugar cane for ethanol, the greenhouse gas released is about 50 percent greater than what occurs from the production and use of the same amount of gasoline. And that statistic holds for at least two decades.

    Brazil will not solve all your problems (unless they’re samba related!). Increased demand for ethanol from Brazil could lead to clearcutting of the rain forest/other fallow grassland.

    Across the full process of growing high-diversity prairie hay, converting it into an energy source and using that energy, we found a net removal and storage of about a ton and a half of atmospheric carbon dioxide per acre. The net effect is that ethanol or synthetic gasoline produced from this grass on degraded land can provide energy that actually reduces atmospheric levels of carbon dioxide.

    It’s a very well written article.

  • Carrboro Screening of "After the Peak"

    Byoliveridley

    I happened to watch an interesting short film called After the Peak about peak oil, the concept (not that revolutionary unless you ask Messrs  Exxon-Mobil, Shell and Dick Cheney!) that oil production will start declining after a certain peak production event. The docudrama made by local film maker James McQuaid was part of a public meeting on the local (Orange County, NC) responses to the coming energy crisis. Interesting conceptually, it was shown as a 30 minute local newscast, with the usual cast of characters, the too handsome eye candy anchor and his female sidekick, the young and breathless “street reporter”, the gray haired expert, and the uber-energetic sports guy! The newscast is set a year into the future when the price of gas is $10/gallon. The documentary of interviews with various community members about the effects of the price of gas on their business/life. In the 30 minutes, he touched upon food, school buses, sports, NASCAR, the poor, commutes, etc. It was an interesting effort, if a little over the top! The fake interviews with the racing track owner who’s closing his track down, the UNC athletic director who has to cancel all his long distance events, the manager of the local food store who threatens food scarcity.

    But is $10 a gallon really a big deal?

    gas-prices.png

    This simple chart shows income adjusted dollar per gallon gas prices (gas prices from 2006, income from 2004, but it should not change too much.)

    Let’s avoid the low income outliers and just compare the U.S and Germany. In April 2006, the U.S was paying $2.95 a gallon and Germany, $8.06 per gallon (ref). If you further adjust that with the per capita income of the two countries, $41,300 for the U.S versus $30,500 for Germany (ref), you will find that the price of gas in Germany is well above $10 a gallon already, they seem to be doing just fine! Maybe they just drive less. The US uses 381 million gallons of gas per day (that’s about 1.2 gallons per day per person). I agree that this comparison is a little flawed because the bulk of the German price is due to taxes, which go back to the government and are presumably used for various good deeds. Also, if the price of gas went up due to shortages, the price differential between Germany and the US would presumably stay constant (unless the Germans lowered taxes). My point is that many countries cope with high gas prices quite well, they just don’t make the same choices the Americans make, 1 acre lots, large SUVs, super long commutes, etc. There are a lot of efficiencies to be had here. The graph below shows the income adjusted gasoline price for a few countries (easy data was available!)

    My take: we need to swiftly move away from gasoline by a) Disincentivizing the use of gasoline in transportation b) Incentivizing the use of electricity for transportation. Electricity can be produced more efficiently, and pollution at the source can be controlled more effectively. A combination of a drastic increase in solar and wind power, coupled with aggressive development in battery technology should more than solve our problem without much recourse to biofuels (that great boondongle).

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    The US guts Environmental Assessments

    Byoliveridley

    Environmental assessment in the U.S. was enshrined in law for the first time when President Richard Nixon signed the National Environmental Policy Act (NEPA) on January 1, 1970. Since then, however, the U.S. has slowly cast aside its role as a leader in the field of environmental assessments, as successive administrations have chipped away at the scope of NEPA, experts say. The cuts have reached a crescendo with President George W. Bush’s administration, and proponents of these assessments worry that pressure to develop natural resources with little oversight of the consequences will lead to an unsustainable future for the U.S.

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    Well, perfect. Now you can claim very factually that “you don’t know of any harmful effects of your actions”.

    The fact is, the attack on NEPA has come, chronically, from a relatively small group of commodity users—timber companies, highway builders—who simply oppose having the public and environmentalists get in the way of their plans and programs,” Houck maintains.

    Can’t say it any better. Information is very important and one thing this Bush administration has been very successful at is reducing the flow of information.

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