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Date: 2005-11-30
From: Mike Weaver
Subject: Re: [Biofuel] Methanol - was Re: neoprene gloves good enough
From: Mike Weaver
Subject: Re: [Biofuel] Methanol - was Re: neoprene gloves good enough
Better to be over-cautious than under-cautious. I wish we could set up a training series and teach interested parties how to brew safely. I dread the thought than someone will make an avoidable error and taint the home-brewing scenario. If I wrote a quick safety punchlist would the greybeards on the list look it over - if approved maybe Keith would post it on the website? I have some informal points in my biodiesel notebook that could probably be expanded. -Mike Keith Addison wrote: >We're veering between incaution and overcaution. There've been some >other messages pooh-poohing safety in general. I'd agree too much >safety is dangerous, but so is too little. What's required is *due* >caution, which needs good information. Here it is: > >http://journeytoforever.org/biodiesel_make.html#moremeth > >More about methanol > >Question: Just how dangerous is methanol? > >Fact: Methanol is a poisonous chemical that can blind you or kill >you, and as well as drinking it you can absorb it through the skin >and breathe in the fumes. > >Question: How much does it take to kill you? > >Short answer: Anything from five teaspoons to more than half a pint, >but nobody really knows. > >Fact: Human susceptibility to the acute effects of methanol >intoxication is extremely variable. The minimum dose of methanol >causing permanent visual defects is unknown. The lethal dose of >methanol for humans is not known for certain. The minimum lethal dose >of methanol in the absence of medical treatment is put at between 0.3 >and 1 g/kg. > >That means it's thought to take at least 20 grams of methanol to kill >an average-sized person, or 25 ml, five teaspoonsful. Or it might >need more than three times as much, 66 grams, 17 teaspoonsful, or >maybe more, and even then it'll only kill you if you can't reach a >doctor within a day or two, and maybe it still won't kill you. > >But it definitely can kill you. If you drink five teaspoonsful of >pure methanol you'll need medical treatment even if it doesn't kill >you. Yet people have survived doses of 10 times as much -- a quarter >of a litre, half a pint -- without any permanent harm. But others >haven't survived much lower doses. Getting rapid medical attention is >crucial, though the poisoning effects can be slow to develop. > >Authorities advise that swallowing up to 1.3 grams or 1.7 ml of >methanol or inhaling methanol vapour concentrations below 200 ppm >should be harmless for most people. No severe effects have been >reported in humans of methanol vapour exposures well above 200 ppm. > >Out of 1,601 methanol poisonings reported in the US in 1987 the death >rate was 0.375%, or 1 in 267 cases. It might have been only 1 in more >than a thousand cases because most cases weren't reported. Most cases >were caused by drinking badly made moonshine, which is a worldwide >problem. > >Fiction: "Methanol is ... a very active chemical against which the >human body has no means of defence. It is absorbed easily through the >skin and there is no means of elimination from the body, so levels of >methanol dissolved in the blood accumulate." > >That's from a British website trying to sell Straight Vegetable Oil >(SVO) solvent additives by frightening people with the alleged perils >of biodiesel. See The SVO vs biodiesel argument > >Fact: 30 litres of fruit juice will probably contain up to 20 grams >of methanol, near the official minimum lethal dose. Methanol is in >the food we eat, in fresh fruit and vegetables, beer and wine, diet >drinks, artificial sweeteners. > >Not only that, methanol occurs naturally in humans. It's a natural >component of blood, urine, saliva and the air you breathe out. It's >there anyway even if you've never been exposed to chemical methanol >or its fumes. > >Methanol is eliminated from the body as a normal matter of course via >the urine and exhaled air and by metabolism. Getting rid of it takes >from a few hours for low doses to a day or two for higher doses. Some >proportion of a dose of methanol just goes straight through, excreted >by the lungs and kidneys unchanged. The normal background-level >quantities of methanol in humans are eliminated and replenished all >the time as a matter of course. > >Fiction: It's largely biodiesel's methanol content that's being >blamed when the same British SVO website charges that biodiesel is >wasteful and environmentally irresponsible. > >Fact: Methanol is readily biodegradable in the environment under both >aerobic and anaerobic conditions (with and without oxygen) in a wide >variety of conditions. > >Generally 80% of methanol in sewage systems is biodegraded within 5 days. > >Methanol is a normal growth substrate for many soil microorganisms, >which completely degrade methanol to carbon dioxide and water. > >Methanol is of low toxicity to aquatic and terrestrial organisms and >it is not bioaccumulated. (It's toxic mainly to humans and monkeys.) > >Environmental effects due to exposure to methanol are unlikely. >Unless released in high concentrations, methanol would not be >expected to persist or bioaccumulate in the environment. Low levels >of release would not be expected to result in adverse environmental >effects. > >Fiction: A European SVO fuel website using similar anti-biodiesel >tactics claims: "Biodiesel is a chemically altered plant oil. However >the process to chemically change the structure of Pure Plant Oil is a >very costly operation and requires a lot of energy, as it removes the >glycerine substituting it by methanol as well as adding other >chemicals, making the end-product poisonous and equally hazardous as >fossil diesel fuel." > >Fact: There is no free methanol in washed biodiesel. All the national >standards require washing. According to US EPA studies methyl esters >biodiesel is less toxic than table salt and more biodegradable than >sugar. It has none of the toxic or environmental hazards of fossil >diesel fuel. > >To put it all in some perspective, methanol is the main or only >ingredient in barbecue fuel or fondue fuel, sold in supermarkets and >chain stores as "stove fuel" and used at the dinner table. It's also >the main ingredient in the fuel kids use in their model aero engines. > >Yes, methanol is a dangerous chemical, but quite how dangerous it may >be is a little hard to say, and it causes surprisingly little harm. >If you're careful and sensible and treat it with caution it won't >harm you either. Many thousands of biodiesel homebrewers worldwide >have been using it for years without serious mishap. > >In our view, the difference between methanol and the really dangerous >chemicals is that although methanol is poisonous, it's a natural >chemical, you'd find it in the Garden of Eden too. It's not something >nature's simply never heard of before and has no way of handling and >neither do you, unlike too many of the 100,000-odd "new" chemicals >now in use which aren't readily biodegradable and do accumulate, and >spread, and keep being implicated in cancer clusters and bizarre >sexual distortions of frogs and so on and on and on. > >There are no reports of carcinogenic, genotoxic, reproductive or >developmental effects in humans due to methanol exposure. Its >environmental effects if any are minimal and short-lived. > >Biodieselers can and do use methanol safely and the biodiesel fuel we >make from it is safe and clean. > >-- With information from: United Nations Environment Programme / >International Labour Organisation / World Health Organization: >International Programme On Chemical Safety, Environmental Health >Criteria 196 - Methanol, from IPCS INCHEM, "Chemical Safety >Information from Intergovernmental Organizations", in cooperation >with the Canadian Centre for Occupational Health and Safety (CCOHS) >http://www.inchem.org/documents/ehc/ehc/ehc196.htm > >See also: > >Safety (MSDS) data for methyl alcohol >http://ptcl.chem.ox.ac.uk/MSDS/ME/methyl_alcohol.html > >Methanol MSDS >http://www.bu.edu/es/labsafety/ESMSDSs/MSMethanol.html > >Methanol as a plant nutrient > >"Methanol is a fixed-carbon nutrient source for plants." -- From >"Agriculture and Methanol", Chapter 7, Methanol Production and Use, >ed. Wu-Hsun Cheng and Harold H. Kung, ISBN 0-8247-9223-8, 1994 (10th >printing) > >"Methanol treatments of C3 plants [most food crops] have been found >to result in growth improvement... As a plant source of carbon, >methanol is a liquid concentrate: 1 cc of methanol provides the >equivalent fixed-carbon substrate of over 2,000,000 cc of ambient >air... Methanol treatments are a means of placing carbon directly >into the foliage... The application of 10-100% methanol to some crops >increased photosynthetic productivity... The uptake of methanol by >plants in light leaves no significant residual methanol above >baseline as detectable by chromotography within 15-30 minutes of >penetration. Treatment with methanol is therefore an inexpensive, >safe, and effective means of providing plants with a source of fixed >carbon and carbon dioxide... An economical means of inhibition of >photorespiration has been sought for decades, and methanol may well >provide the solution... The control of photorespiration across the >food crops of the world could double yields." -- Greg Harbican and >Peter G., Biofuel mailing list, 8 Sep 2004. For discussion see: >http://snipurl.com/j94f >Methanol and Plants >http://snipurl.com/j94e >Use for wash water - methanol > >Note however that the authors of Methanol Production and Use caution >that the application of methanol to crops still requires further >study before we all "rush out to spray methanol". > >Most of the excess methanol used in the biodiesel process ends up in >the glycerine by-product layer, and the rest stays in the biodiesel. >If you don't reclaim it for re-use (you should!) the portion that's >in the biodiesel gets washed out when you wash the fuel, mostly with >the first wash. The first wash-water probably won't contain more than >5-6% methanol (as well as some sodium or potassium lye and some >soap). You could try spraying it on half a small patch of weeds and >don't spray the other half to see what happens. Choose a bright sunny >day. > >ends... > >Best > >Keith > > > > > >>Methanol is readily absorbed through the skin. I have used it >>around the house as a solvent for years and yes the odd little drip >>on your skin won't hurt but for anything more than that you should >>use protection. Inhaling the vapors should be avoided. As for >>methoxide you should be taking great care to avoid exposure period. >> >>Joe >> >>Ken Provost wrote: >> >> >> >>>On Nov 29, 2005, at 1:04 PM, Kenji James Fuse wrote: >>> >>> >>> >>> >>> >>> >>>>What do others use for hand protection from methanol and methoxide? Do >>>>neoprene gloves provide adequate enough protection from methanol and >>>>methoxide? >>>> >>>> >>>> >>>> >>>I realize this is sacrilege, but I don't use ANY >>>PROTECTION!!!!!........ >>> >>> >>>I find the methanol evaporates very quickly from my hands, leaving >>>no ill effects (yet :-)) except a certain "chappiness" that can be >>>remedied with various OTC preparations (hand lotion). >>> >>> >>>Methoxide solution spilled on the hands has a tendency to produce >>>a slight burning sensation after a couple of minutes that can be >>>neutral- >>>ized instantly with running water. >>> >>>Really. >>> >>>-K >>> >>> > > >_______________________________________________ >Biofuel mailing list >Biofuel.org >http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org > >Biofuel at Journey to Forever: >http://journeytoforever.org/biofuel.html > >Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): >http://www.mail-archive.com/biofuel.org/ > > _______________________________________________ Biofuel mailing list Biofuel.org http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): http://www.mail-archive.com/biofuel.org/
