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.

Similar Posts

  • |

    Flood risks from global warming underestimated.

    Byoliveridley

    As CO2 levels in the atmosphere increase, plants uptake less water from the soil. Betts’ model indicates that there could be a 6 percentage point increase due to this effect on top of the 11% increase in global water flows due to direct climate effects.

    BBC NEWS | Science/Nature | Climate flooding risk ‘misjudged’

    Researchers say efforts to calculate flooding risk from climate change do not take into account the effect carbon dioxide (CO2) has on vegetation. Higher atmospheric levels of this greenhouse gas reduce the ability of plants to suck water out of the ground and “breathe” out the excess. Plants expel excess water through tiny pores, or stomata, in their leaves. Their reduced ability to release water back into the atmosphere will result in the ground becoming saturated.

    Feedbacks, always a problem and hard to predict.

  • Canada – No new coal plants?

    Byoliveridley

    For a minute I thought the pain from playing volleyball last night, plus opening my computer up sleepily at 5:45 in the morning before catching an early bus to work had me hallucinating, but yes, the Canadian federal government actually wants to impose a moratorium on the construction of new coal fired power plants unless they include sequestration (which to me means no new power plants).

    The federal government is planning sweeping new climate-change regulations for Canada's electricity sector that will phase out traditional coal-fired power

    Any new coal plants will have to include highly expensive – and unproven – technology to capture greenhouse gas emissions and inject it underground for permanent storage, Environment Minister Jim Prentice said in an interview yesterday.

    Ottawa also plans to impose absolute emission caps on utilities' existing coal-fired power plants and establish a market-based system to allow them to buy credits to meet those targets, Mr. Prentice said.

    via reportonbusiness.com: Ottawa takes aim at coal power.

    I have a certain distrust for this government, so details are crucial. The right things are being said:

    1. All new plants will need sequestration
    2. A cap and trade to deal with existing coal fired power plants
    3. Phase out of facilities after “fully amortized life” – Not clear on exactly what that means
    4. 90% Emissions free power sector by 2025

    As the article points out, Canada relies on coal much less than a lot of other countries, only 18% of current emissions are from coal, as opposed to the US, where about 40% is from coal.

    So, time to celebrate? Not exactly. Canada’s latest release of 2007 data indicates horrendous performance.

    Canada 2007 GHG Inventory

    Overall, total increase was 6 Megatonnes from 2004 to 2007. But the increases from the Tar Sands were nearly 16 Mt, meaning most of Canada’s other sectors saw decreases, thanks to a number of mild winters and greater efficiency.

    Clearly, this performance is going to continue until the Tar Sands are included in any CO2 reduction strategies, whatever we do, or don’t do with the coal will have a little bit of impact, but will definitely not help Canada achieve any of its short or long term goals.

    So, one cheer for this announcement. I suspect that the administration needs something to take to meetings, and is hoping that a coal moratorium will distract people from the biggest culprits, the Tar Sands and our insanely high per capita GHG footprint. A “no new coal” moratorium would be a huge deal in the States, and off the charts in China or India as far as reducing emissions go. But Canada, not bad, but definitely not good enough!

    The Tar Sands will only be stopped when the US steps up to the plate and gets its Cap and Trade going.

  • GE – weakening air pollution standards

    Byoliveridley

    GE – we bring good things to life (and kill them with Diesel exhaust).

    Clean Air Watch – Blog for Clean Air

    General Electric Co., which is running a marketing campaign promoting itself as environmentally friendly, has pushed to weaken smog controls for railroad locomotives in rules about to be proposed by the Environmental Protection Agency.

    The rules, which could take effect between 2011 and 2017, are designed to cut smog and soot levels and would replace standards adopted in 1997. Since the rules would apply to new locomotives and could require changes on older ones, they would have a big effect on GE, which dominates the nearly $2 billion-a-year North American locomotive market. While the nation’s other locomotive maker and diesel-engine makers say they are prepared to meet the proposed new standard, GE argues it is “unlikely to be achieved” and has proposed a weaker one.

    I have nothing to say, just another example of the plutocracy-protectionary principle, nothing new, same old Modus Operandi.

  • |

    Smoking bans in North Carolina?

    Byoliveridley

    After this morning’s post about Tennessee, I got curious and wanted to see what we were doing in North Carolina on smoking bans. So, I looked up my very own NC General assembly homepage and used their full text bill search function (key word smoking!). Here’s what I found.

    In the State Senate

    Great! Senate Bill S635 will ban smoking in all public places indoors except in tobacco shops, designated smoking rooms in hotels and for “research”. Follow the progress of this bill using the bill’s very own rss feed!

    In the House

    Not so good, House bill H259 has been referred to committee. But it has giant loopholes for all bars and “private clubs”. It has its very own rss feed too.

    Observations

    1. It is good to see that my representatives Kinnaird (we share a yoga class on Monday nights!) and Insko are co-sponsors on the bills. But I live in that bastion of progressivism (in the South, anyways!) Chapel Hill/Carrboro, so this is pretty unsurprising!
    2. My question to the House is this: Why are bartenders, employees of bars and private clubs, and patrons of such establishments considered not worthy of protection from second hand smoke? As someone who goes out drinking often, this is where all my exposure to second hand smoke occurs.
    3. Kudos to North Carolina for designing an accessible and easily searchable bill repository complete with rss feeds, way to go!

    Once I hear back from Sen. Kinnaird on the prospects of legislation this session, I’ll be sure to post about it.

    Update: See this. The House and Senate bills have gotten a lot closer, and most of the loopholes are gone.

  • | |

    Bhutan to pay for others climate sins

    Byoliveridley

    Bhutan is a small country nestled in the Himalayas, breathtakingly beautiful and “quaint”. Unfortunately, it’s about to be hit by a truck!

    Reuters AlertNet – FEATURE-Bhutan to pay for others climate sins

    The retreat of Bhutan’s glaciers presents an even more formidable and fundamental challenge to a nation of around 600,000 people, nearly 80 percent of whom live by farming.

    Bhutan’s rivers sustain not only the country’s farmers, but also the country’s main industry and export earner — hydro-electric power, mostly sold to neighbouring India.

    For a few years, Bhutan’s farmers and its hydro power plants might have more summer melt water than they can use. One day, though, the glaciers may be gone, and the “white gold” upon which the economy depends may dry up.

    The threat led the government’s National Environment Commission to a stark conclusion.

    “Not only human lives and livelihoods are at risk, but the very backbone of the nation’s economy is at the mercy of climate change hazards,” it wrote in a recent report.

    Scientists admit they have little solid data on how Bhutan’s climate is already changing, but say weather patterns are becoming increasingly unpredictable.

    Well, as I keep saying, Americans and Europeans will be incovenienced by global climate change, Asians and Africans will die. I don’t have an answer, though, which is depressing on this gray and cloudy Friday morning…