Guest guest Posted February 3, 2006 Report Share Posted February 3, 2006 Jafa- That's company propaganda, anyway. Of course the half-life of hydroxyl radicals is very short -- it's because they're extremely potent radicals. The more potent a radical, the more readily it reacts with things, the more damage it does, the shorter its half-life. And when you breathe in hydroxyl radicals in, what do you think they're going to react with? Your body. And probably your skin and hair and eyeballs and nails on the outside too. That said, I suppose you could safely use the machine Mercola's selling as long as you turn it off awhile before going into the room -- if you don't mind whatever acceleration of aging it causes to all your possessions in that room. > I spoke with a representative from the company. He explained how > the filter is actually safe. > > First of all he said the half life of the hydroxyl radicals > and superoxide ions is very short, even when breathed in - > seconds. They are in a very unstable form and will combine with > other elements to make water, if they don't attach to a > contaminant. These substances seek out contaminants in the air > and when they attach, it neutralizes the radical and the > contaminant drops to the ground also neutralized. > > Were you aware of this? - Quote Link to comment Share on other sites More sharing options...
Guest guest Posted February 3, 2006 Report Share Posted February 3, 2006 But, what about what he said about them becoming inert in seconds? And attaching to other elements, forming water. Are you saying this is incorrect? jafa Idol <Idol@...> wrote: Jafa- That's company propaganda, anyway. Of course the half-life of hydroxyl radicals is very short -- it's because they're extremely potent radicals. The more potent a radical, the more readily it reacts with things, the more damage it does, the shorter its half-life. And when you breathe in hydroxyl radicals in, what do you think they're going to react with? Your body. And probably your skin and hair and eyeballs and nails on the outside too. --------------------------------- - Helps protect you from nasty viruses. Quote Link to comment Share on other sites More sharing options...
Guest guest Posted February 3, 2006 Report Share Posted February 3, 2006 Jafa- >But, what about what he said about them becoming inert >in seconds? And attaching to other elements, forming water. Are >you saying this is incorrect? I'm having trouble finding data on the half-life of hydroxyl radicals in air, but here's an excerpt of Wikipedia's entry <http://en.wikipedia.org/wiki/Hydroxyl> on them: >>The hydroxyl radical has a very short in vivo half-life of approx. >>10-9 s and a high reactivity. This makes it a very dangerous >>compound to the organism. Unlike superoxide, which can be >>detoxified by superoxide dismutase, the hydroxyl radical cannot be >>eliminated by an enzymatic reaction, as this would require its >>diffusion to the enzyme's active site. As diffusion is slower than >>the half-life of the molecule, it will react with any oxidizable >>compound in vicinity. The only means to protect important cellular >>structures is the use of antioxidants such as glutathione and of >>effective repair systems. The fact that hydroxyl radicals serve a useful purpose in the atmosphere doesn't mean that it's healthy to generate a large supply of them indoors. From the Allergy, Sensitivity & Environmental Health Association there's this article <http://www.asehaqld.org.au/Air%20Quality/chemical_warfare_at_work.htm> entitled " Chemical Warfare at Work: Your Office is Out to Get You! " . >>The key culprits in 'indoor smog' are hydroxyl radicals which are >>desperate to find other chemicals to attach themselves to and they >>react very quickly with most compounds in the air. Hydroxyl >>radicals play a major part in forming photochemical smog in >>polluted cities and nobody had previously looked for them indoors. >>It was found that " as many as a trillion hydroxyl radicals can be >>present in every cubic meter of indoor air " , this was much higher >>than was expected indoors and is higher than levels of hydroxyl >>radicals out of doors in the night air. >> >>Hydroxyl radicals are formed by reactions between ozone from office >>equipment such as copiers and VOC's given off by people. Once >>hydroxyl radicals are produced, they blast apart all the other >>VOC's around them creating harmful chemicals such as formaldehyde, >>aldehydes, ketones, acetic acid and nitric acid, which are more >>reactive than the parent compounds. These can play a key role in >>damaging some electronic equipment as hygroscopic dust which >>settles on circuit boards can be formed. While this is dry, it is >>not much of a problem, but once humidity rises an ionic solution >>can form which creates a conducting bridge between components. >>Electrical errors can then occur. This type of reaction causes >>crosstalk or noisy phone lines. Here's a little of what the Linus ing Institute has to say <http://lpi.oregonstate.edu/f-w97/reactive.html> on the subject. >>Under normal metabolic conditions, each cell in our body is exposed >>to about 1010 molecules of superoxide each day. For a person >>weighing 150 pounds, this amounts to about 4 pounds of superoxide >>per year, a substantial amount! Once formed, superoxide is >>converted to other ROS. In the presence of small amounts of iron or >>copper, hydroxyl radicals may be formed. Hydroxyl radicals are >>extremely reactive and can cause severe damage to cells and >>tissues. The recent, though as yet unconfirmed, evidence that >>excess iron intake may be linked to increased risk of heart disease >>and cancer may, in part, be explained by the role iron plays in the >>conversion of superoxide to hydroxyl radicals, resulting in >>oxidative damage to arteries and genes. >> >>Oxidative Damage >> >>The ROS formed by the mechanisms explained above can cause >>oxidative damage to various biological molecules. For example, >>hydroxyl radicals can damage cell membranes and lipoproteins (the >>particles carrying cholesterol and fat in the blood stream) by a >>process called lipid peroxidation. Lipid peroxidation occurs by a >>radical chain reaction, i.e. once started, it spreads rapidly and >>affects a great number of lipid molecules. Proteins may also be >>damaged by ROS, leading to structural changes and loss of enzyme >>activity (an enzyme is a protein that catalyzes the rate of a >>chemical reaction without itself being changed). Oxidative damage >>to DNA also occurs at a high rate under normal metabolic >>conditions. It has been estimated that the DNA in each cell of our >>body suffers 10,000 " oxidative hits " per day, leading to the >>formation of more than twenty different oxidative DNA lesions. Many >>of these lesions are known to cause mutations. There are a number >>of DNA repair enzymes that can remove these lesions, but their >>repair success is not perfect. Therefore, oxidative DNA damage and >>mutations accumulate with age, which may contribute to cancer. And then there's this tasty bit from the California Environmental Protection Agency's Air Resources Board Report to the Legislature on Indoor Air Pollution in California <http://www.arb.ca.gov/research/indoor/ab1173/rpt0705.pdf> which pretty much says it all. >>2. 1.3. 1 Reaction Products >> >>Indoor organic chemicals react with oxidants such as ozone, >>hydroxyl radicals, and nitrate radicals to produce secondary >>pollutants. Weschler (2004) provides an excellent review of studies >>investigating indoor chemical reactions published since 2000. The >>review focuses on the importance of hydroxyl radicals in indoor >>reactions, reactions occurring on indoor surfaces, and the impact >>secondary reaction products have on building occupants. Traditional >>analytical methods often do not detect some of the short-lived, >>highly reactive compounds that are produced. Sensory measurements >>have been used to detect changes in indoor air quality associated >>with the reactions. It is thought that the ozone/terpene reactions >>dominate indoor chemistry based on the frequent presence of ozone >>and ubiquitous presence of terpenes in indoor environments (Weschler, 2004). OK, I admit it doesn't _quite_ say it all. This additional excerpt from a couple pages later in the report is very informative too. (Thank god for OCR!) >>2. 1 . 3. 2 Sick Building Syndrome >> >>Sick Building Syndrome (SBS) is a term used to describe a >>collection of irritant and neurological effects that occur while >>occupants are in a building, that generally disappear when affected >>people are out of the building. Specific causes of SBS have not yet >>been firmly identified. The most common symptoms include eye >>irritation, congested nose, headache, fatigue, difficulty >>concentrating, and dry skin (Tenbrinke et a!., 1998). SBS differs >>from building-related illness (BRI; see Biological Contaminants >>section) in which an identifiable factor causes a specific illness >>such as bacteria causing Legionnaires' disease or humidifier fever. >> >>In an attempt to identify factors related to SBS, Seppanen and Fisk >>(2002) reviewed the literature to summarize factors associated with >>SBS. They found that relative to natural >>ventilation, air conditioning was consistently associated with a >>statistically significant increase in the prevalence of one or more >>SBS symptoms, by approximately 30-200%. This finding reinforces the >>use of ventilation as a mitigation measure for reducing indoor >>pollution, but still may not identify the primary cause. The review >>identifies several confounding factors that are not affected by the >>HVAC type: quantity of carpet or textile surfaces; sealed windows; >>building age; depth of the building bays; and dusty surfaces. A >>European review also found an association between ventilation and >>comfort and health (Wargocki et a!., 2002). >> >>Investigators who study indoor reactive chemistry suggest that the >>degradation products of VOCs may be responsible for the reported >>SBS symptoms (Carslaw, 2003; Wolkoff et a!., 2000; Wolkoff and >>Nielsen, 2001 ; Weschler, 2004). These reactions include >>ozone/terpene reactions with propagation of hydroxyl radicals and >>reactions on indoor surfaces such as ozone interacting with carpet. >>The impact that the products of indoor chemistry can have on >>building occupants has also been studied on a physiological level >>(Weschler, 2004). So yes, in clinical terms, I think the guy you spoke to is talking out of his ass. I'm not going to speculate on whether that's due to dishonesty or mere ignorance, but the end result is the same. In fact, I have to admit *I* was talking out of my ass when I speculated that running a hydroxyl generator when you're not in the room might be OK, because I didn't stop to think (always a mistake) of the secondary reaction products, which are going to tend to stick around a lot longer, and which have their own host of ill effects. (That's the same reason California's Air Resources Board is adamantly opposed to ozone generators, BTW. <http://www.arb.ca.gov/research/indoor/ozone.htm> Not only is ozone bad for you, but many of the reaction products formed by its actions are bad for you too.) ly, I not only have enough of a passing familiarity with chemistry to know that, but I've also read about that very issue as it applies to sick building syndrome, so mega-duh and a slap to the face for me for not thinking to mention it in the very beginning of this thread. As to the water issue, yes, reactions with hydroxyl radicals often form water, but all that's required for that is the donation of a hydrogen ion to the hydroxyl radical. As some of the material above shows (and as vast realms of further documentation that I didn't post here demonstrates) reaction with hydroxyl radicals very often just turns one pollutant into another. There's no alchemical transmutation of toxic compounds into water, and there's no magical immediate settling to the ground (or floor) of all compounds produced by hydroxyl reactions. - Quote Link to comment Share on other sites More sharing options...
Guest guest Posted February 4, 2006 Report Share Posted February 4, 2006 Thanks for the info.... That was very helpful. Idol <Idol@...> wrote: Jafa- >But, what about what he said about them becoming inert >in seconds? And attaching to other elements, forming water. Are >you saying this is incorrect? I'm having trouble finding data on the half-life of hydroxyl radicals in air, but here's an excerpt of Wikipedia's entry <http://en.wikipedia.org/wiki/Hydroxyl> on them: __________________________________________________ Quote Link to comment Share on other sites More sharing options...
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