marc@haddock.UUCP (02/06/86)
I a not usually a reader of net.med, but after reading an article recently in "PC Week", I thought that I might try to start up some conversation. The issue was dated January 21, 1986, Vol 3, No 3. The article was titled "Using VDT's in the workplace". The article talked about the ever increasing use of VDT's in the work environment and related topics such as their safety. It touched on some different laws which have been created to try and protect users of the things, and also some proposed legislation as well as interrest groups opposed to the regulation. It talked about different surveys conducted concerning the stress and related pain caused by VDT's. It is very interresting and worth while reading if you haven't already. One very interresting section talked about reproductive problems experienced by males and I quote: "The male reproductive system may also be at risk. A recent Swedish study of workers exposed repeatedly to ELF radiation suggests a decrease in male fertility and an increase in the congenital malformations of their offspring." ELF, by the way stands for Extremely Low-Frequency waves which are caused in the case of VDT's by the flyback transformer used to regulate the high speed scanning of the electron beem across the screen. There are also some other waves emited which are "X-rays, radio-frequency (RF) waves, microwaves and very low-frequency (VLF) waves". The article groups these waves into 2 catagories, "ionizing" and "non-ionizing". Apparently, the non-ionizing waves (VLF and ELF in the range of 0 to 30KHz) are the most recent area of concern were "In the past 5 years, at least 11 'clusters' of reproductive problems in connection with VDT usage have been reported in the US and Canada. ... The first such cluster came to light when four out of seven pregnant VDT operators at the Toroonto Star newspaper had babies with birth defects. According to a Bureau of National Affairs report, seven other women working in the same department who did not use VDT's gave birth to normal children during the same period". It is all quite interesting to read. Have any of you had any problems related to VDT's or computer usage in general? I know that myself, that I have been having problems with my right eye spasming recently, but the optomitrist claims that my eyes are fine and that there isn't anything to worry about. The problem has started sinse I have stopped using an Apollo DN550 color monitor and have degraded to a VT100 like terminal (I changed jobs). When I don't use the machine for a couple of days at a stretch, the problem disappears. I've tried reverse video, different intensity/contrast levels with no noticable improvement. Anyway, let's here your thoughts on this subject. Marc Evans, WB1GRH Interactive Systems Corp Boston, MA
emjej@uokvax.UUCP (02/11/86)
/* Written 2:30 pm Feb 6, 1986 by marc@haddock in net.med */ > ELF, by the way stands for Extremely Low-Frequency waves which are caused in > the case of VDT's by the flyback transformer used to regulate the high speed > scanning of the electron beem across the screen. There are also some other > waves emitted which are "X-rays, radio-frequency (RF) waves, microwaves and > very low-frequency (VLF) waves". The article groups these waves into 2 > categories, "ionizing" and "non-ionizing". When you (or the article) say "waves," is that sound, or electromagnetic? One thing that bothers the <expletive> out of me is the sound generated by those <expletive> flyback transformers. > Apparently, the non-ionizing waves (VLF and ELF in the range of 0 to 30KHz) > are the most recent area of concern were "In the past 5 years, at least 11 > 'clusters' of reproductive problems in connection with VDT usage have been > reported in the US and Canada. ... The first such cluster came to light when > four out of seven pregnant VDT operators at the Toronto Star newspaper had > babies with birth defects. According to a Bureau of National Affairs report, > seven other women working in the same department who did not use VDT's gave > birth to normal children during the same period". Can you say "post hoc ergo propter hoc?" :-) Who knows what other things these women might have had in common? Did they smoke? Go to lunch together? One certainly can't tell from the article, but it all helps to raise the level of hysteria about radiation. James Jones /* End of text from net.med */
hollombe@ttidcc.UUCP (The Polymath) (02/14/86)
>> ... "In the past 5 years, at least 11 >> 'clusters' of reproductive problems in connection with VDT usage have been >> reported in the US and Canada. ... The first such cluster came to light when >> four out of seven pregnant VDT operators at the Toronto Star newspaper had >> babies with birth defects. According to a Bureau of National Affairs report, >> seven other women working in the same department who did not use VDT's gave >> birth to normal children during the same period". If experimental design and statistics were made educational requirements there would be less foolishness of this sort. You want anecdotes? OK: Where I work there are hundreds of VDT's in the building. At least one, and usually two or three, in every office. _Everybody_ has one. In the last year there must have been at least a dozen children born to women who work here. (The place looked like a maternity ward for a while (-: ). Not one birth defect in the bunch. So what does that prove? Absolutely nothing. Just as the Toronto Star situation proves absolutely nothing. People who have a workplace and job in common are very apt to have other things in common. Since it's not feasible to control for such with human subjects the _only_ way to do a valid experiment would be to randomly select a large group of VDT operators from the _national_ (or preferably _world_) population of VDT operators and see if the rate of birth defects in that group differs significantly from that of the general population. If you really wanted a useful study for the money you'd run a multivariate analysis and look at everything from make and model of VDT to the type of chair and posture of the operator. To the best of my (admittedly limited) knowledge all the studies done to date that have approached the above methodology have found _no significant effect_ from working with VDTs while pregnant. -_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_ The Polymath (aka: Jerry Hollombe) Citicorp(+)TTI 3100 Ocean Park Blvd. Geniuses are people so lazy they Santa Monica, CA 90405 do everything right the first time. (213) 450-9111, ext. 2483 {philabs,randvax,trwrb,vortex}!ttidca!ttidcc!hollombe