Some Environmental Hazards of Lighting Systems Ä a Comparative View John Mills c.1992 John Mills Dr. Ira Lubell, the Health Officer for Santa Cruz county, California, in thinking about the disposal problem of fluorescent lights, has written, "Looking for energy-efficient alternatives to incandescent lighting has produced hazards which society must weigh and assess as to the relative harm." Let's take Dr. Lubell's advice and examine various lighting systems and their potential environmental impacts. A Brief Look into the Past Some time, long ago in the dim beginnings of human history some extremely clever woman - or perhaps man, discovered how to make fire. From that point onward the flames of oil lamps, candles, or gas jets became our first lighting system. Thousands of years later Mrs. O'leary's cow is said to have started the great Chicago fire by kicking over a lantern, and, if it's true, this certainly illustrates the awesome hazard potential of this type of lighting. Surely there must be a safer way to light the barn. Even though most of us think of Thomas Edison as the inventor of the electric light, others in fact proceeded him. In 1820 an englishman named de la Rue connected a coiled platinum wire in a glass tube to a battery and noted that the wire gave off visible light. Between the years 1810 and 1872 a number of inventors also discovered that an electric arc jumping between two carbon rods produced light. This was the great grandfather of our current fluorescent lamps. In 1879, at the youthful age of 32, Tom edison solved the practical problems and opened the door to the first commercial production of incandescent light bulbs. At about this same time improvements in dynamos, the development of transmission wire and switches combined to make large scale electrical lighting systems a reality. And so it was that just over 100 years ago this great electrical lighting experiment we are now involved in now, began. How is light measured? The experts in this field routinely delve into the mysterious world of: lamberts, apostilb, bondel, lux, and even nits. You and I can simplify a bit by thinking in terms of the foot-candle. This is the amount of light cast by a candle at one foot distance on a one square foot surface. One foot- candle is also equal to one lumen. A 100 watt incandescent light bulb is rated at about 1710 lumen. This means that one foot form the bulb it gives as much light as 1710 candles. On the brightest summer days with the sun overhead the natural outdoor light would be about 10,000 foot- candles. Moonlight, on the other hand, is about 0.03 foot-candle. Over-illumination Amory Lovins has stated, "most modern architecture is extremely energy intensive with absurdly high lighting levels..." Could this be true? In order to answer this I set out to find out how sensitive our eyes really are. Selig Hect calculated in the 1940s that only from 50-150 quanta are required to produce the sensation of light - far far fainter than even moonlight. In the days before electrical lighting, British government officials set the light minimum at 1 foot-candle. This was called the grumble line because below this level small printing became hard to read and clerks were apt to grumble. In the 1930s most illumination was below 50 foot-candles. Today, however, some authorities recommend 100 or more foot-candles of illumination,. Our homes and businesses now blaze about 100 times brighter than those of the candle and kerosene lamp era. If one foot- candle is all that is necessary for reading and conducting business why do we use so much more today? In the 1920s studies were done that indicated that the more light a person had the sharper their vision became. Light bulb manufacturers, electric companies, and enthusiastic sales personnel endeavored to bring more lighting and hence better vision to schools, factories, and businesses everywhere. Incandescent bulbs produced too much heat to be practical at levels over about 50 foot-candles. After the introduction of fluorescent lamps in 1938 the ceiling on foot-candle levels could be raised even higher. Throughout the years these high illumination levels have become established recommendations for architects and engineers. Ancient religion too, may have played a part in our desire for more light. The Zoroastrians of Persia associated light with positive virtue. After all, who wants to be thought of as dim? Businessmen have used high lighting levels as effective psychological means to attract attention and increase sales. The most compelling argument for using more light, however, is that it results in better vision. This is sort of like an investment Ä we pay our money and get a return. The problem is that a lot of investment is required for only a little return. If we increase lighting levels, for example, ten times over the one foot-candle level vision improves only 1.3 times. 100 times more lighting yields a 1.7 improvement. This would indicate that the practice of using high level illumination over large floor space areas may be a poor personal and business investment. It also may be environmentally unsound in that it is an inefficient use our our limited electrical resources. Perhaps Mr. Lovins is right when he chides us for our over-illumination. Times have changed since the 1920s, and today the electric utilities and the lamp manufacturers generally urge responsible conservation of electricity. What About Incandescent Light Bulbs? Incandescent light bulbs are all quite similar. The halogen lamp has a halogen substance included to prolong the life of the filament. The quartz halogen has a small quartz bulb and can withstand higher temperature thus putting out more light. Screw-in type quartz halogen bulbs are now available for either 120 vac or 12 VDC use. These bulbs are from 10 to 50 percent better in efficiency than standard incandescents. Incandescent bulbs would seem to be composed of relatively nontoxic substances and therefore not to be a disposal problem. Some incandescent bulbs are advertised at having 20,000 hour, or even 135,000 hour lifetimes, however, 3000 hours would be typical for most halogens, and standard bulbs may last only 750 hours. In general longer lived bulbs are less efficient ones. When used on alternating current incandescent bulbs will have a slight flicker at 120 times per second. Most of the energy from these lamps is given off as heat and in the red to yellow area of the spectrum. If you live in a cool climate this extra heat will be welcome. In the summer, in hotter areas it may be a nuisance. Incandescent bulbs do not generally emit excess amounts of radio interference or microwaves. They emit only comparatively low levels of E.L.F magnetic fields. Some track lighting units with individual transformers may have substantially higher levels of E.L.F. magnetic fields. Fluorescent Lamps Fluorescent lamps are either of the long tube or the new screw in compact type. The principle of operation is the same in each. An electric arc jumps from one end of the tube to the other through hot mercury vapor producing ultraviolet light which causes the phosphor inside of the tube to glow. Fluorescent lamps are popular these days. One of their greatest virtues is they produce just about the most light for the electricity they use. Another advantage is a longer life. A quality fluorescent will last 10,000 hours. Because of the way they work, however, there are other things that come out of these tubes and their circuitry that may be less welcome than their abundant light. Electric arcs are also radio transmitters. As early as 1910 a voice transmission was made between Stockton and Sacramento, California using an electric arc. By 1917, giant 500 kilowatt arc transmitters were sending radio signals across continents and over oceans. Every time we turn on a fluorescent lamp we also activate an arc transmitter that send out electromagnetic waves of many types. Some of these may be a health hazard or have the ability to interfere with our thinking process. Extremely Low Frequency (E.L.F.) Magnetic Fields All fluorescent lamps need special electric circuits for starting and power regulation. This is called a ballast. This ballast and its associated wiring produces E.L.F. magnetic fields that we should be aware of. Some new ballasts have been designed to produce lower amounts of E.L.F. Studies indicate that these E.L.F. fields have the capacity to cause serious health problems and to interfere with the thinking process. Richard Perez and Bob-O Schultze have written an in-depth article about E.L.F. in issue number 23 of Home Power. This article, with its excellent bibliography, is a fine resource for more information on these magnetic fields. Radio Noise Fluorescent lamps and their circuitry also generate other, higher band radio waves.if you have a portable radio and you put the antenna near a fluorescent lamp you will hear signals on the a.m. band, the long wave and short wave areas. This is called broadband radio interference. These signals are generated in the tube and ballast. They then use your wiring as an antenna to radiate off into space. Incandescent lamp dimmers and inverters can also produce this type of interference. As we have increased our use of electrical items broadband radio interference has also increased world-wide to the point where it has limited communications and some scientific research. Dr. John Kraus mentions the impact of this interference on radio astronomy in his interesting book The Big Ear. Microwaves You might be surprised to find that fluorescent lamps also produce microwaves. So does your wife, your husband, your dog, and your cat. In fact any object that is warm produces microwave energy. There is an important difference however. Fluorescent lamps produce a lot more microwaves than natural sources Ä thousands to many thousands of times more On the other hand, the amount they produce is far below the levels considered a health hazard by the most conservative government standard. So why worry? Well, responsible scientists have found that pulsed microwave energy can penetrate deeply into and be absorbed by models of the human head; also that pulsed microwaves can interact with our nervous system in strange and still unexplained ways. It is possible, but by no means yet proven, that the microwave radiating from fluorescent lamps may be having some measurable effect on our senses of hearing, taste, smell, our memory or our ability to think clearly. Since fluorescent lamps have only been around for 54 years the impact of the long term pulsed microwave exposure from them is still unknown. (We can only judge from the trends in business and politics conducted in fluorescent lit buildings in the past 50 years Ä Ed.) Flicker and Color Think for a moment about the light form a fireplace or candle. There is a slow irregular flicker that we easily recognize. some authorities would even claim that this type of light has special romantic power. Now think about a fluorescent tube powered by the a.c. line or an inverter. It flashes on and off at a rate of 120 times per second in a regular synchronized pattern. Some compact fluorescent lamps with electronic ballasts flash at faster rates. Some people find this strobe effect annoying while others don't seem to mind. Incandescent lamps powered by pure d.c. do not flicker but rather give off a steady continuous glow. Lighting systems approximate but do not exactly match natural daylight in color. Most of us are aware of how how color can affect our moods and perceptions. Just imagine eating a hunk of green meat or a black tomato. Although some of this work is considered controversial, John Ott has spent years investigating the effects of light and color on plants, animals, and humans. The Toxic Waste Problem The manufacturers of fluorescent lamps have made a sincere and successful effort to reduce the levels of toxic substances in their products. Over the years they have introduced new and safer phosphors. They have also been able to use less mercury. Because of the way they work, however, all fluorescent lamps contain variable amounts of mercury. Some compact fluorescents also contain small quantities of a radioactive substance to aid in starting. We can toss a regular incandescent light bulb into the trash, and if it should break, it would release a small quantity of inert gas, typically argon or nitrogen, glass fragments, some tungsten wire, and the bulb base. Halogen lamps would also release a small amount of halogen substance which might have environmental consequences depending upon its quantity and composition. When we dispose of fluorescent tubes, in addition to the incandescent bulb elements we will release mercury. Mercury has been recognized as toxic for a long time. The Mad Hatter of Lewis Carroll's Alice in Wonderland most likely slipped off his rocker because of his occupational exposure to mercury compounds used in the preparation of felt for hats. Mercury and its compounds are used in a number of consumer items; however, the recent trend in industry has been toward reduction or elimination. The N.I.O.S.H. recommended exposure limit for mercury vapor is 0.05 milligrams per cubic meter of air. Fluorescent tubes contain from 20-350 milligrams of mercury. A little math here will show that one fluorescent tube contains enough mercury to contaminate a rather large air space. Fortunately, only a fraction of the mercury from a broken tube will enter the air at any one time. Tests reveal that about 10% of the total will vaporize in a 14 day period. This indicates that a broken fluorescent lamp in your home will not be be a major disaster; however, if this occurs it might be wise to ventilate the area and dispose of all bulb fragments promptly, out of doors, in the trash. You might want to do this gently, if possible, so as not to stir up a lot of dust. The breakage and disposal of larger numbers of fluorescent tubes does indeed seem to be a recognized toxic waste problem and potential health hazard. Thoughts about Risk The judgment of environmental hazards of lighting systems involves the problem of how each of us defines risk. This is sort of personal matter and it probably depends upon our age, our philosophy of life, our occupation, and perhaps upon the information we have. Our sensitivity is also important. Consider the case of someone with a cold who can not smell smoke. No question, their ability to warn us of a fire has been impaired. Hazards may be dramatic and immediate like a candle in a hay barn or more subtle and long term like the effects of groundwater contamination. Some decisions that we make about risk might only affect us personally or they might also affect large numbers of others. What Can We Do? We can affect our own and the larger environment by our choices of lighting systems and by how we use them. Depending upon our personal assessments of the risks involved we might use conventional incandescent or halogen lamps for study or work areas where the lamp will be near the user. We could also utilize efficient fluorescent lamps in outdoor or more remote locations that need low cost, long-lasting illumination. Using only the needed amount of light for the task is basic and perhaps wise. We might remember that E.L.F. magnetic fields and pulsed microwaves from fluorescent lamps and their ballasts penetrate through normal walls and floors. They do this with little loss in power and the easiest way to reduce exposure is to either change to incandescents or move further away from the fixture and tube. When you move twice as far away the E.L.F. magnetic fields and microwaves become one quarter as strong. Common sense counsels that we be careful in handling fluorescent tubes to prevent breakage and to insure their safe disposal. Dan de Grassi, a solid waste disposal planning expert has recommended that homeowners put plastic trash bags over tubes prior to breaking them, if that is necessary, in order to reduce the exposure to mercury vapor. The Luminous Conclusion We are privileged, perhaps, to live at a time when each of us can use relatively inexpensive and powerful electric light. Today, with the flip of a switch even a little child can call up and control more light than the mightiest ancient kings. Yet we need to be mindful of the consequences and responsibilities of this remarkable power. This genie has come out of the lamp and it is probably safe to assume that the lighting business has a bright future ahead. Sources and Resources 1. Aitken, H.G.J. The Continuous Wave Technology and American Radio 1900-1932, Princeton University Press, 1985 2. Barron, C. Study of 226 Microwave Exposed Employees, Lockheed Corp., Burbank CA 1954. 3 Facts on File 1987 Hazardous Chemicals on File, TM, Inorganic Mercury. M005 1-2 4. Frey, A.H., "Auditory System Response to Modulated Electromagnetic Energy". J. Appl. Physiol. 17: 689-692, 1962 5. Frey, A.H. "Auditory System Response to Radio Frequency Energy", Aerospace Med1961 32:1140 6. Gibson, R.S. and Moroney, W.F. "The Effect of Extremely Low Frequency Magnetic Fields on Human Performance, A Preliminary Study." Naval Aerospace Medical Research Laboratory, Pensacola, Florida, 1974 7. Hopkins, R.G., Petherbridge, P and Longmore, J., Daylighting, Heineman: London, 1966 8. Keating, P.W. Lamps for a Brighter America, McGraw Hill, Copyright 1954 by the General Electric Company 9. Kraus, John D. The Big Ear, Cygnus-Quasar Books, P.O. Box 85 Powell, Ohio 54065 10. Lovins, Amory B. "World Energy Strategies Facts Issues and Opinions", Friends of the Earth, Inc. 1975 11. Olsen, R.G. and Hammer, W.C. "Thermographic Comparison of Temperature Probes used in Microwave Dosimetry Studies" Proceedings of the 1978 Symposium on Electromagnetic Fields in Biological Systems. Ottawa, Canada I.M.P.I. Naval Aerospace Medical Research Laboratory Pensacola, Florida. 12. Ott, John, "The 'Light' Side of Health", The Mother Earth News, Jan/Feb 1986 (interview). 13. Wertheimer, N. and E. Leeper, "Electrical Wiring Configurations and Childhood Cancer", American Journal of Epidemiology 109: 273: 284. 3057 words