------------------------------ From: jmstrang@mtu.edu (Jeffrey M. Strang) Subject: Re: PCB capacitors Date: 17 Aug 1994 13:47:44 -0400 Now, I realize that this is a newsgroup devoted to audio pursuits, but seeing as how I am a graduate student in environmental engineering, I just can't resist putting in my 2 cents worth. PCB's (polychlorinated biphenyls) are a large group of over 100 similar chemicals that were widely used in power transformers, capacitors, and other applications where a fire-resistant dielectric was needed. Their use and production was banned sometime in the late 70's. The major problem with PCBs is that they do not break down once they are let out into the environment; they endlessly cycle between the atmosphere, the soil, and lakes. Because of that, fish easily contact PCBs in the Great Lakes (for example), and it accumulates in their fatty tissue. When children and pregnant women consume contaminated fish, the possibility of developmental problems or birth defects exists. Other than those groups, problems from exposure to PCB's, aside from a possible slight increase in the incidence of cancer, are insignificant. I wouldn't worry about your fingers falling off from touching leaking capacitors. Unless you sat down to a bowl of the stuff for breakfast every morning, you shouldn't have any problem. PCB's are NOT deadly toxins; they're just difficult to clean up. Burning them in an incinerator or landfilling them are the only acceptable ways to dispose of them. While throwing away your 6 leaking caps will not jeapordize the local community, bear in mind that it's not really the right thing to do with them. Finally, the real culprit in PCBs is not the PCB, but a byproduct of its manufacture that was not generally removed from the PCB before being sold. [I'll be surprised if this gets posted! At least Russell will be enlightened.] Jeff Strang ------------------------------ From: msv@unlinfo.unl.edu (mark vanroojen) Subject: Re: PCB capacitors Date: 18 Aug 1994 15:34:20 GMT Jeffrey M. Strang (jmstrang@mtu.edu) wrote: [cut by rgd.] I'd like to hear a little more about the cancer risk, since this is what worries me about the PCBs in caps. I have called my local health department about these, and was told information consistent with what is printed above, but they added one bit: When burned PCBs produce dioxins which *are* much more dangerous than the PCBs. Also, it seems worth mentioning that many communities have toxic waste collection days at which they'll accept capacitors from old radios to be disposed of properly. There's one here in Lincoln on Saturday where I'm going to take a cap from an amplifier that I want to get rid of safely. BTW, despite Jeff's skepticism that the moderator would consider this topic pertinent to audio, I find it quite useful, and expect many home-builders/fixer-uppers will too. Mark ------------------------------ From: cgb@bellatrix.biochem.ualberta.ca (Colin Bigam) Subject: Re: PCB capacitors Date: Thu, 18 Aug 1994 10:58:42 -0600 msv@unlinfo.unl.edu (mark vanroojen) writes: >I'd like to hear a little more about the cancer risk, since this is >what worries me about the PCBs in caps. I have called my local health >department about these, and was told information consistent with what >is printed above, but they added one bit: When burned PCBs produce >dioxins which *are* much more dangerous than the PCBs. I imagine Jeff can give you more specific details on the cancer risk, but it's really pretty small for most of us. A friend of mine has worked in electronics for 30-odd years, and has at times literally been up to his elbows in PCBs while fixing or gutting transformers. It doesn't seem to have harmed him at all, and he's fathered two (healthy) kids while in his 50s. As for burning them to produce dioxins, this is a real, but fairly small danger. Yes, it happens, but it takes quite a lot of heat to burn the suckers. (say, 200C or thereabouts) That's the REAL problem with them--you can't get rid of them! Colin ------------------------------ From: jmstrang@mtu.edu (Jeffrey M. Strang) Subject: Re: PCB capacitors Date: 18 Aug 1994 12:58:48 -0400 Mark said in the post previous to this one that when burned, PCB's generate dioxins, which are a group of one of the most toxic compounds known to man. He is right. One of the reasons for banning PCBs was that when electrical transformers were hit by lightning, the 'fireproof' PCB's caught on fire and spewed these dioxins into the air. These dioxins are the same thing that are a byproduct of PCB manufacture, and are much more dangerous than the PCB's themselves. I was wrong on one point, though: dioxins didn't generally make it out of the chemical plants. They are only released into the atmosphere when PCB's are burned (although properly equipped incinerators control their emissions). Mark also wondered about the cancer-causing effects of PCB's. I did a little reading and found that they are not considered carcinogenic (cancer-causing) at any level that we are likely to be exposed to them. However, they do cause the previously mentioned developmental problems in unborn and small children at trace levels, so any DIYer's kids shouldn't play with old capacitors. Incidentally, old flourescent lighting ballasts (transformers) often have PCB filled capacitors in them. Jeff Strang ------------------------------ From: mje@pookie.pass.wayne.edu (Michael J. Edelman) Subject: Re: PCB capacitors Date: 18 Aug 1994 19:39:06 GMT In article hf4@tolstoy.lerc.nasa.gov, msv@unlinfo.unl.edu (mark vanroojen) writes: >Jeffrey M. Strang (jmstrang@mtu.edu) wrote: > >[cut by rgd.] > >I'd like to hear a little more about the cancer risk, since this is >what worries me about the PCBs in caps. I have called my local health >department about these, and was told information consistent with what >is printed above, but they added one bit: When burned PCBs produce >dioxins which *are* much more dangerous than the PCBs. The risk is supposedly due to dioxins, and is approximately zero. Dioxins, despite being the favortite doomsday poinson of the last decade, are pretty innocuous. A railroad tank care of the stuff derailed and dumped a few thousand gallons on a small Italian town about 20+ years ago. Result? SHort term contact dermatitis in a lrge segement of the population. *No* long term effects. No elevated rates of any cancers. There are many far more toxic and tumor promoting materials surrounding us every day, like gasoline- which kills a lot of careless people every year. As long as you don't make a practice of drilling holes in capacitors and sucking out the contents you'll never come in contact with the stuff. Do you drink? Do you use mouthwash? Smoke? Those are the three biggest casues of oral cancer in this country. The risk from PCBs is many orders of magnitude smaller than the risk of using mouthwash. --mike