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Scientists Baffled By Unknown Source of Ozone-Depleting Chemical 303

schwit1 writes: Scientists have found that, despite a complete ban since 2007, ozone-depleting chemicals are still being pumped into the atmosphere from some unknown source. "Carbon tetrachloride (CCl4), which was once used in applications such as dry cleaning and as a fire-extinguishing agent, was regulated in 1987 under the Montreal Protocol along with other chlorofluorocarbons that destroy ozone and contribute to the ozone hole over Antarctica. Parties to the Montreal Protocol reported zero new CCl4 emissions between 2007-2012. However, the new research shows worldwide emissions of CCl4 average 39 kilotons (about 43,000 U.S. tons) per year, approximately 30 percent of peak emissions prior to the international treaty going into effect. "We are not supposed to be seeing this at all," said Qing Liang, an atmospheric scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the study published online in the Aug. 18 issue of Geophysical Research Letters, a journal of the American Geophysical Union. "It is now apparent there are either unidentified industrial leakages, large emissions from contaminated sites, or unknown CCl4 sources."
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Scientists Baffled By Unknown Source of Ozone-Depleting Chemical

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  • From the wikipedia (Score:5, Informative)

    by mveloso ( 325617 ) on Wednesday August 20, 2014 @06:42PM (#47716337)

    Not sure how accurate this is, since it's from wikipedia, but the reference seems legit.

    In 2008, a study of common cleaning products found the presence of carbon tetrachloride in "very high concentrations" (up to 101 mg/m3) as a result of manufacturers' mixing of surfactants or soap with sodium hypochlorite (bleach).[18] []


    "By mixing surfactants or soap with NaOCl, it was shown that the formation of carbon tetrachloride and several other halogenated VOCs is possible"

  • by ShanghaiBill ( 739463 ) on Wednesday August 20, 2014 @06:51PM (#47716389)

    Nope. CCl4 is not used in HVAC systems. You are thinking of freon [], which is not what TFA is about.

  • by Anonymous Coward on Wednesday August 20, 2014 @06:54PM (#47716413)

    Or nobody. This is un-sourced nonsense.

  • by Smallpond ( 221300 ) on Wednesday August 20, 2014 @07:17PM (#47716533) Homepage Journal

    Clorox had $5.6B in sales last year, of which 10% was laundry products according to their annual report. A gallon of bleach sells for $2, so if all their sales generated 275M gallons of bleach-containing chemicals = 1M m3 x 101 mg/m3 = 100,000 gm. Nope. That amount is negligible compared to what the study reports.

  • by geekoid ( 135745 ) <`dadinportland' `at' `'> on Wednesday August 20, 2014 @08:21PM (#47716915) Homepage Journal

    You should really read those links. Seriously dude, just linking something you don't actually understand as some sort of proof just mkas you look foolish.

    The first one made it worse:

    The law reduces air pollution controls, including those environmental protections of the Clean Air Act, including caps on toxins in the air and budget cuts for enforcement. The Act is opposed by conservationist groups such as the Sierra Club with Henry A. Waxman, a Democratic congressman of California, describing its title as "clear propaganda."

    Among other things, the Clear Skies Act:

    Allows 42 million more tons of pollution emitted than the EPA proposal.
    Weakens the current cap on nitrogen oxide pollution levels from 1.25 million tons to 2.1 million tons, allowing 68% more NOx pollution.
    Delays the improvement of sulfur dioxide (SO2) pollution levels compared to the Clean Air Act requirements.
    Delays enforcement of smog-and-soot pollution standards until 2015.
    By 2018, the Clear Skies Act will supposedly allow 3 million tons more NOx through 2012 and 8 million more by 2020, for SO2, 18 million tons more through 2012 and 34 million tons more through 2020. 58 tons more mercury through 2012 and 163 tons more through 2020 would be released into the environment than what would be allowed by enforcement of the Clean Air Act.[2]

    In August 2001, the EPA proposed a version of the Clear Skies Act that contained short timetables and lower emissions caps [3]. It is unknown why this proposal was withdrawn and replaced with the Bush Administration proposal. It is also unclear whether or not the original EPA proposal would have made it out of committee.

    The second one--Signed into law by President Lyndon B. Johnson on December 17, 1963

    The third one-- Nixon combined existing groups into one, for budget reasons.
    However, I would argue the the Pubs of the 60's and 70s are vastly different then the pubs of today. Post religious right control.

  • by adolf ( 21054 ) <> on Wednesday August 20, 2014 @08:56PM (#47717117) Journal

    I don't know of a single refrigerant in common use which remains liquid at STP. Almost all of them evaporate very, very quickly at atmospheric pressure.

    Indeed, the most common one in new equipment (these days) is R-134a. Which is the same thing that goes into the "canned air" commonly sold and used for cleaning computer gear, and is also the same chemical used in the more common forms of freeze spray (the difference being whether it is dispensed as a liquid via an internal dip tube, or as a gas by simple lack of a dip tube).

    What were you going on about, again?

    Oh, right. Clues.

  • by Nethemas the Great ( 909900 ) on Wednesday August 20, 2014 @09:09PM (#47717189)
    CCl4 otherwise known as R-10 in the HVAC world, is a coolant and is a precursor to R-11 and R-12. Both of which happily decompose to CCl4.
  • by Rich0 ( 548339 ) on Wednesday August 20, 2014 @10:46PM (#47717627) Homepage

    When I open up the tap in my kitchen sink, am I "blowing off water straight to atmosphere" ??? Of course not, showing us all that you didnt know that Carbon tetrachloride was a liquid while making your first post blaming a bunch of people that you clearly have other different issues with.

    Saying that something is a liquid/solid/gas/etc is a bit of a simplification. The reality is that substances exist in equilibrium between various phases, and this shifts based on temperature/pressure.

    If you spill some water on a sidewalk in the summer and come back an hour later, you won't see any water, because it will evaporate - probably fairly quickly depending on the humidity.

    Carbon tetrachloride is much more volatile than water in practice. The boiling point isn't all that much lower, but unlike water there is almost none of it present in the atmosphere to start out. That greatly facilitates evaporation per Le Chatelier's principle.

    Oh, and I don't think anybody uses carbon tetrachloride in air conditioners. Old ones certainly use CFCs though, and most of those boil at a lower temperature. Carbon tetrachloride has been a known carcinogen for ages, so industrial uses have been shifting away from it for a while.

  • by Tyrannicsupremacy ( 1354431 ) on Thursday August 21, 2014 @08:38AM (#47719401)
    And it worked? No, you just have a censored internet. []

Nothing ever becomes real till it is experienced -- even a proverb is no proverb to you till your life has illustrated it. -- John Keats