Drugs in the water: Behold the power of synergy

Byoliveridley

funky MathES&T Online News: Can drugs found in water harm humans?

Researchers agree that aquatic species face the greatest risk from exposure to low levels of pharmaceuticals, such as synthetic hormones, which can act as endocrine disrupters at environmental levels. However, little is known about the potential human health effects arising from complex drug mixtures.

Well, it is often more difficult to analyze complex mixtures because Experimental Design 101 makes you want to isolate the effects. And when you do compounds one by one in series, the tendency is to always add them up from the individual experiments. Unfortunately, body chemistry is not like that. I’ve always wanted to design a study that started complex and then tried to isolate later.

To his surprise, Pomati observed that this mixture of drugs at environmental levels inhibited the growth of human embryonic kidney cells. After 48 hours of exposure, cell proliferation was reduced by 10–30% compared with controls. However, no inhibition was observed when cells were exposed to only the toxic cancer drug at environmental levels.

Well, that seems conclusive enough, but here comes the “Experimental Design 101” Scold:

The results show that the growth inhibition is not due to the single most cytotoxic compound alone. But that does not conclusively prove that synergistic or additive effects exist between drugs in the mixture, cautions Thomas Heberer of the Institute of Food Chemistry at the Technical University of Berlin. To show that the individual drugs behave additively, Heberer suggests that researchers should analyze the effects of compounds with a common mode of action, such as antibiotics, alone and in various mixtures.

No, No, and No. Doing this presupposes that you know that mechanism of action, meaning you’ve half answered your question. The question Heberer is trying to answer is “do individual drugs with the same mode of action behave additively”. The question Pomati is trying to answer is “Can we demonstrate cytotoxic effects of a cocktail of drugs at ambient levels in a laboratory setting”? These are two completely different questions and Pomati’s question is more valuable at this point in time. Heberer’s strategy, on the other hand, will keep a lab well funded for years to come! But, it is very much the final step.

It is more important at this point in time to demonstrate other effects such as endocrine disruption, mutagenicity, etc in the lab at environmentally relevant levels of mixtures. Then we can get a better handle on which  effects are relevant and which ones to ignore.

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    Green Scolding and Media Victim Blaming

    Byoliveridley


    Dracula Lurks in Your Set-Top Box – NYTimes.com

    Most Americans are guilty of a similar if less costly squandering of
    energy when it comes to their cable or satellite TV boxes. A new study
    released on Tuesday by the National Resources Defense Council shows that
    set-top boxes in the United States consume nearly as much energy when
    not in use as when they are on, costing a cumulative $2 billion a year.

    Dear media, let’s break down the choices consumers have with regards to set top boxes:

    1. Not get one, and hence lose access to encrypted channels, digital cable, etc, which are now de rigueur
    2. Get one, and unplug it every time, which means reaching behind (as you kindly mention), unplugging, and waiting for restart, etc. My Telus box usually takes a couple of minutes at least to reinitialize, and behaves a bit weirdly for another minute afterwards. So how many people will do this?
    3. Be scolded by you for not being environmentally friendly.

    Now, let’s see what would happen in a real, and properly regulated market.

    1. There would be little connection between the set top box and the content. You would get a box, or use your computer, and just put in a card from your cable company for decryption. While cablecards kinda exist, the reason you haven’t heard of them is because cable companies want you captured by their expensive hardware. separate the two, box manufacturers are free to sell you fancy boxes like this one that can manage all your media, have a friendly interface, cost less, look cool, and consume less energy, and can use all these as marketing points.
    2. There would be sensible regulation on ALL electric devices to include standby mode, with automatic sleep mode. So, if something is not in use, it shuts off in 15 minutes. Seems difficult? Computers do this all the time, routinely. A set top box is just an underpowered computer.

    So, let’s not blame the consumer here, shall we? If anyone is guilty, it is media and telecommunication oligopolies that don’t let us actually have free choice, while simultaneously claiming that any regulation is anti-  free market.

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    California Ban on Diacetyl?

    Byoliveridley

    Flavoring-Factory Illnesses Raise Inquiries – New York Times

    For a good background on flavoring-factory lung disease (formerly known as popcorn worker’s lung), check out the Pump Handle’s many posts, especially this recent one. Short primer, diacetyl is the chemical that gives popcorn its so called buttery taste (and smell, it’s fake!!). Well, there’s pretty good evidence that diacetyl causes bronchiolitis obliterans. Some symptoms…

    Bronchiolitis obliterans renders its victims unable to exert even a little energy without becoming winded or faint.

    “The airways to the lung have been eaten up,” said Barbara Materna, the chief of the occupational health branch in the California Department of Health Services. “They can’t work anymore, and they can’t walk a short distance without severe shortness of breath.”

    OSHA has been unwilling to seriously regulate diacetyl, so California, as it is wont to do, is considering banning this killer chemical.

    But in California, which has 28 flavoring plants known to use diacetyl, some legislators and government officials seem unwilling to wait. A bill to ban diacetyl in the workplace by 2010 has passed two committees in the State Assembly and could be taken up by the full body this summer. It is the first proposal of its kind in the nation. Assemblywoman Sally Lieber, the author of the bill, said she introduced it because of what she said was the slow response by the flavoring industry, which is largely self-regulating on occupational safety. “What we’ve heard is that the flavoring industry has known for years that this is potentially a problem, and they haven’t taken action,” said Ms. Lieber, a Democrat.

    I am all for California’s regulation. But as written, this law will only protect workers in California. They should also consider going one step further by restricting the use of diacetyl in food sold in California. Only then can the giant market that is California exert its influence on the diacetyl manufacturers and users.

  • Oil refineries underestimate release of emissions, study says

    Byoliveridley

    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!

    Do we expect measurement based techniques to start being used in the US and Canada? One would hope so, but, don’t hold your breath!

  • Please stop drinking bottled water

    Byoliveridley

    This blog(ger) is not prone to order people around, but it is going to now. STOP DRINKING BOTTLED WATER. If you live in a reasonably well taxed/well run town in the first world, just drink from the tap. If your town’s drinking water sucks, get a water filter/purifier, use a refillable drinking water system, and lobby your town council hard to improve their drinking water infrastructure so you can drink from the tap.
    Pablo Calculates the True Cost of Bottled Water TreeHugger

    In summary, the manufacture and transport of that one kilogram bottle of Fiji water consumed 26.88 kilograms of water (7.1 gallons) .849 Kilograms of fossil fuel (one litre or .26 gal) and emitted 562 grams of Greenhouse Gases (1.2 pounds).

    Yes, he corrected his calculations down to 6.7 gallons, but that is an awful lot of wastage, criminal wastage in fact.

  • Nuclear Energy not Carbon Free?

    Byoliveridley

    Who would have thunk it, turns out that uranium mining and nuclear waste storage result in significant carbon emissions…
    New Debate Over Nuclear Option

    Now, some scientists and other experts are beginning to raise a different question about nuclear power: Is it really as clean as supporters contend? A report, released on Mar. 26 by a British nongovernmental organization called the Oxford Research Group, disputes the popular perception that nuclear is a clean energy source. It argues that while nuclear plants may not generate carbon dioxide while they operate, the other steps necessary to produce nuclear power, including the mining of uranium and the storing of waste, result in substantial amounts of carbon dioxide pollution. “As this report shows, hopes for the climate-protecting potential of nuclear energy are entirely misplaced,” says Jürgen Trittin, a former minister of the environment in Germany and a contributor to the report. “Nuclear power cannot be promoted on environmental grounds.”

    The report, called “Secure Energy? Civil Nuclear Power, Security and Global Warming,” examines a number of risks from nuclear power development, including concerns over the disposal of radioactive waste and the threats from terrorist groups. But its most novel component may be the quantitative examination of carbon emissions on a comprehensive basis. “Carbon emissions are a global problem and it’s time to look at the carbon released by nuclear power globally,” says Jan Willem Storm van Leeuwen, author of the report’s chapter on carbon emissions. “The assumption has long been that the [greenhouse] effect is zero, but the evidence shows otherwise.”

    carbonfacts_sm.jpg“Novel component”?, well, I would not go that far, it appears that the authors performed a carbon footprint analysis and concluded that the carbon footprint of nuclear fission energy production was somewhere between renewables and fossil fuel power generation, which is not entirely surprising. Coupled with all the other issues facing nuclear energy, and the obvious environmental justice issues that impact the siting of any new plant or waste repository, nuclear energy should not be a very serious option at all. Unfortunately, it’s a great boondongle for the developers of the plants because the subsidies and power pricing mechanisms ensure profits for the developer at the expense of the general public, and waste disposal issues can forever be postponed, eventually leaving governments (and tax payers) to pick up the tab.

    By the way, go read Jamais Cascio’s interesting post about the carbon footprint of a cheeseburger. The “nutrition like label” shown here is something I wish to see in almost every product used! It would make the regulation of carbon a lot less complicated. It appears that England will take the lead on this concept, see Carbon Labelling (yes, 2 L’s, the “correct” spelling!).

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    Al Franken is good for health

    Byoliveridley

    You know what's in your food and many beauty products. Senator Al Franken wants to make it possible to see exactly what's in your household cleaning products as well.The Minnesota Democrat introduced a bill in the U.S. Senate requiring producers to fully disclose all ingredients on their product labels, including those suspected of causing long-term harm. Currently the warnings on cleansers are designed to prevent immediate harm due to swallowing, splashing in eyes or other unintended uses.

    via Kare 11

    It would seem common sense to have information on labels, especially on the harsh and powerful chemicals we use every day. You may not understand what they mean, or how to pronounce the chemical names, but you don’t have to! Organizations such as the Environmental Working Group have extensive information on common high volume chemicals so people can match what they see on the label with what they would like to avoid.

    But it is not the law of the land in the US, or Canada for that matter. Al Franken, comedian, talk show host and an intelligent man turned senator would like to change that in the US. Of course, we in Canada would benefit as well.

    Chemical manufacturers aren’t having any of this.

    There’s always a concern about turning labels into encyclopedias,” Brian Sansoni of the Soap and Detergent Association, in Washington, D.C., told KARE Tuesday.

    Pretty insulting, claiming that your consumer does not like encyclopedias, or is not capable of reading and googling.

    Information helps drive consumers to safer alternatives. If you see two cleaners, both of which claim to work equally well, a quick read of the ingredients will drive you to the safer (or simpler) choice. Clearly, sale by obfuscation is the preferred marketing strategy here.

    If I were American, I would call my senator/congressperson and ask them to support Al Franken.