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Controversy exists concerning the health risks from exposures to radiofrequency/microwave irradiation (RF/MW). The authors report exposure-effect relationships in sentinel patients and their co-workers, who were technicians with high levels of exposure to RF/MW radiation. Information about exposures of patients with sentinel tumors was obtained from interviews, medical records, and technical sources. One patient was a member of a cohort of 25 workers with six tumors. The authors estimated relative risks for cancer in this group and latency periods for a larger group of self-reported individuals. Index patients with melanoma of the eye, testicular cancer, nasopharyngioma, non-Hodgkin's lymphoma, and breast cancer were in the 20-37-year age group. Information about work conditions suggested prolonged exposures to high levels of RF/MW radiation that produced risks for the entire body. Clusters involved many different types of tumors. Latency periods were extremely brief in index patients and a larger self-reported group. The findings suggest that young persons exposed to high levels of RF/MW radiation for long periods in settings where preventive measures were lax were at increased risk for cancer. Very short latency periods suggest high risks from high-level exposures. Calculations derived from a linear model of dose-response suggest the need to prevent exposures in the range of 10-100 microw/cm(2).

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In December 1995, ambient radon levels exceeding 10,000 Bq/m3 were measured in a basement shelter workroom of a multilevel East Talpiot, Jerusalem, public elementary school (six grades, 600 students). The measurements were taken after cancers (breast and multiple myeloma) were diagnosed in two workers who spent their workdays in basement rooms. The school was located on a hill that geologic maps show to be rich in phosphate deposits, which are a recognized source for radon gas and its daughter products. Levels exceeding 1000,000 Bq/m3 were measured at the mouth of a pipe in the basement shelter workroom, the major point of radon entry. The school was closed and charcoal and electret ion chamber detectors were used to carry out repeated 5-day measurements in all rooms in the multilevel building over a period of several months. Radon concentrations were generally higher in rooms in the four levels of the building that were below ground level. There were some ground-level rooms in the building in which levels reached up to 1300 Bq/m3. In rooms above ground level, however, peak levels did not exceed 300 Bq/m3. Exposure control based on sealing and positive pressure ventilation was inadequate. These findings suggested that radon diffused from highly contaminated basement and ground-floor rooms to other areas of the building and that sealing off the source may have led to reaccumulation of radon beneath the building. Later, subslab venting of below-ground radon pockets to the outside air was followed by more sustained reductions in indoor radon levels to levels below 75 Bq/m3. Even so, radon accumulated in certain rooms when the building was closed. This sentinel episode called attention to the need for a national radon policy requiring threshold exposure levels for response and control. A uniform nationwide standard for school buildings below 75 Bq/m3 level was suggested after considering prudent avoidance, the controversies over risk assessment of prolonged low-level exposures in children, and the fact that exposures in most locations in the Talpiot school could be reduced below this level. Proposal of this stringent standard stimulated the search for a strategy of risk control and management based on control at the source. This strategy was more effective and probably more cost effective than one based on suppression of exposure based on sealing and ventilation. Because many Israeli areas and much of the West Bank area of the Palestinian National Authority sit on the same phosphate deposits, regional joint projects for surveillance and control may be indicated.

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Importation of raw asbestos (90% chrysotile; 10% crocidolite) for manufacture of cement products and other uses, including friction materials and spraying, had dropped to under 3000 tons by 1993 from a peak of 10,000 tons per annum in the late 1970s. Drops in use, manufacture, persons exposed in manufacture and measured exposure levels followed heightened public concern over the carcinogenic effects of asbestos products, despite a relatively high worker exposure standard of 400,000 f/m3. The atypically low ratio of reported deaths from lung cancer compared to mesothelioma in asbestos cement workers up to 1992 (1:2.5) is suggested to be a consequence of low baseline risks for lung cancer mortality in Israel and dropping smoking levels. Exposure to asbestos use and asbestos in place remain, but total risk should drop after 2010 if imports continue to drop. These projections may be altered by trade between Israel and its neighbors following peace agreements. Reductions in risk will have resulted from reduction in exposure brought about by reductions in manufacture and use.

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The potential danger to humans of exposure to chemicals shown to be carcinogenic in animals has become increasingly clear in the last 20 years. A gap still exists, however, between the appreciation of the risk by scientists and the willingness of public health authorities to reduce it. Three pesticides, shown repeatedly to produce over a dozen different types of cancer in rats and mice, were discovered in inordinately high concentrations in Israeli milk and dairy products. The three pesticides--alpha-BHC, gamma-BHC (lindane), and DDT--had been shown to be present for ten years or more at mean concentrations up to 100 times those found in U.S. dairy products--with resultant concentrations in breast milk being possibly 800 times greater than those in the United States--yet neither the Ministry of Health nor the Israel Cancer Association made any apparent moves either to warn the public or to rectify the situation. A small consumer organization, Consumer Shield, brought the issue into the open. Through public pressure, court action, and the threat of further legal redress--and despite repeated attacks in the media by the milk producers, the Ministry, and the Cancer Association--Consumer Shield forced the authorities to outlaw the use of alpha-BHC and lindane (DDT no longer being in general use). The ban resulted in a precipitous drop in the concentrations of these substances in Israeli milk. Recent epidemiological and laboratory findings suggest that the dramatic drop in breast cancer mortality rates subsequent to the pesticide ban could be a direct result of that ban.

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Thirty-eight workers from a factory producing nickel-cadmium and other types of batteries came to us for medical evaluation. They included 21 women and 17 men (seniority 2-20 years, age range 31-63 years), and represented a self-selected subset of 700-900 ever-employed and 200+ recently or currently employed workers in the factory. Thirty-four worked on the nickel-cadmium assembly line. Symptoms and signs included: headache in 34; weakness, fatigue and lassitude in 26; dizziness in 16; pruritus and skin eruptions in 37; gingivitis, teeth loss and caries in 34; nasal congestion, nosebleeds and anosmia in 30; cough, phlegm production, wheezing and shortness of breath in 26; "asthma" in 14; bone pain in 18; urinary frequency, beta 2 microglobulinuria and kidney stones in 17; and sterility or multiple abortions (33) in 8 of 21 women. One additional patient had died from an "amyotrophic lateral sclerosis-like syndrome", while CT scans in six workers revealed brain atrophy. One other worker had leukemia, and two had died from cancer (lung and pancreas). Those who had worked for more than 10 years had more symptoms and signs than shorter-term employees, especially neurological illness, bone pain and urinary tract problems, including beta 2 microglobulinuria. Past blood and urinary cadmium levels were in the range of 1.6-8.7 micrograms/dl and 8-306 micrograms/l, respectively. Our findings indicated that: a) health risks for workers were not confined to the nickel-cadmium assembly line or to older workers, b) hazardous exposures still existed and illness appeared in new workers after a clean-up and intervention program, and c) exposures involved increased risks for renal disease and cancers. Finally, there is a need to control exposures and determine health risks in the full cohort of those ever employed, in the workers' children, and in the surrounding environment (air, ground, water) due to the dumping of waste from the plant.

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Some 1,100 residences and places of work and 400 schoolrooms in Israel were tested for ambient air radon activity concentration in response to requests by the owners, tenants, or local authorities. A polyethylene vial containing activated charcoal was exposed to room air in each of these structures for 7 days, sealed, and transported to the laboratory. Adsorbed radon was extracted with a toluene-based cocktail which was then subjected to liquid scintillation counting. Mean radon activity concentrations were found to vary from city to city by more than an order of magnitude, indicating strong regional differences. The countrywide geometric mean was found to be 38 Bq/m3; the median, 37. The range for these means was 6-77 Bq/m3; for the medians, 11-100 Bq/m3. The highest reading was 9,100 Bq/m3. Our results are basically in line with those from the United States and much of Europe, but apparently higher than those found in the United Kingdom and Japan. It may be fairly said that mass testing for radon (222Rn) inside buildings in the United States began in the wake of the finding of a radon activity concentration in excess of 100,000 Bq/m3 in the home of the Watras family in Boyertown, PA in December 1984. To date, literally millions of American buildings have been tested, and mandatory testing of schoolrooms has begun in some states. In Israel, by contrast, where such a dramatically high measurement has not (yet) occurred, only 5 structures had been checked for radon by 1989.(ABSTRACT TRUNCATED AT 250 WORDS)

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Volatile N-nitrosamines are very potent carcinogens. They can be approximately 5 million times more powerful than saccharin. One of two principal methods is generally used when assaying rubber products for nitrosamine content: (1) the German method (aqueous extraction) or (2) the U.S. method (dichloromethane extraction). When 16 types of baby-bottle nipples and children's pacifiers were tested recently, relatively high levels of nitramines, nitrosamines, and nitrosatable precursors were found. Eighty-one percent failed to meet the strict Dutch standards (based on the German method), but only 37.5% would have been banned according to U.S. regulations, which ignore nitrosatable-precursor content. Up to one-third of the nitrosamines present in a rubber nipple may migrate into the milk in the bottle within a few hours. Transfer into infant formula may exceed 40%, and transfer into saliva may be even higher. Thus, a highly contaminated nipple may cause a 5-kg infant who drinks 1 l/d to ingest approximately 2 micrograms/kg body weight.d of nitrosamines. To this, add any exposure resulting from pacifier use or from in vivo nitrosation of precursors. Therefore, daily exposure of infants may, in the worst case, conceivably reach 4-5 micrograms/kg body weight.d. Entire average daily exposure of an American adult to volatile nitrosamines from major sources is estimated to be less than 0.05 micrograms/kg body weight.d. Infants who use products like those tested may, therefore, be exposed daily to less than or equal to 100 times more of these carcinogens than are adults.(ABSTRACT TRUNCATED AT 250 WORDS)

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N-nitrosodiethanolamine (NDELA) is a carcinogenic, non-volatile nitrosamine that has been shown to pass readily through the skin of animals and humans. It has often been found as a contaminant in cosmetics. Twenty different suntan lotions, available in Israel, both liquids and creams, were analyzed for NDELA content. Most products contained undetectable or trace levels, but 3 were found to be contaminated with as much as 27 ppb of the nitrosamine. Continual use of such products, especially by small children and infants, may significantly increase their exposure to NDELA.

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Sixteen types of children's pacifiers and baby-bottle nipples, bought in shops in Israel but produced both there and elsewhere in the world, were analyzed for their contents of N-nitrosamines, which have been shown to be potent carcinogens in animals, and of nitrosatable amines. Two methods were used: one, originating in the United States, involved dichloromethane extraction of total volatile N-nitrosamines from the nipples and pacifiers, and the other, from the Federal Republic of Germany, consisted of analysis of N-nitrosamines and their amine precursors that migrated into artificial saliva. N-Nitrosodibutylamine (NDBA). N-nitrosodiethylamine (NDEA), N-nitrosodimethylamine (NDMA). N-nitrosopiperidine (NPIP), and N-nitrosopyrrolidine (NPYR) were detected by the first method, at individual levels as high as 369 ppb. Using the second method, NDBA, NDEA, NDMA, and N-nitrosomorpholine (NMOR) were detected at concentrations up to 41 ppb, in addition to the three nitrosatable amines dibutylamine, diethylamine, and dimethylamine. Upon nitrosation in the artificial saliva, these amines produced not only the related N-nitrosamines but also relatively high levels of the corresponding N-nitramines (N-nitrodibutylamine, N-nitrodiethylamine, and N-nitrodimethylamine), probably formed by oxidation of the N-nitrosamines by peroxides used for vulcanization of elastomers. Thus, if N-nitramines are not measured in addition to N-nitrosamines after nitrosation, the second method may underestimate the quantities of nitrosatable amines present in artificial saliva extracts. Whether N-nitramines, some of which have been shown to be both mutagenic and carcinogenic, also occur in the saliva of babies exposed to these products remains to be confirmed. Of the samples tested, 50% failed to meet both the U.S. and the FRG regulations. A larger percentage, 60%, would not conform to the new standard suggested in the United States, and more than 80% failed to comply with the even stricter Dutch standard.

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The amount of natural and man-made infrasound that man is subjected to is larger than is generally realized. The few studies that have concerned themselves uniquely with the physiologic effects of moderate-to-high levels of infrasound exposure (as opposed to audible sound or vibrational exposures) have failed to demonstrate significant effects on man other than those concerning the inner ear and balance control. But the existing studies indicate that inner ear symptomatology due to moderate-to-high levels of infrasound may be more common than is generally appreciated. At very high sound pressure levels (greater than 140 dB), ear pain and pressure become the limiting factors. Ear muffs and ear plugs appear to offer slight protection from the effects of infrasound, but quantification of this is still lacking. Direct evidence of adverse effects of exposure to low-intensity signals (less than 90 dB) is lacking. The need for further research in this field is clearly indicated.

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