An uncommon pattern of polyneuropathy induced by lifetime exposures to drift containing organophosphate pesticides.

The natural history of chronic peripheral polyneuropathy following lifetime low-level organophosphate (OP) exposure was investigated. A pilot study (1984-1987) conducted in rural communities in Israel detected subtle reversible in-season changes in nerve conduction patterns of 17 field workers out of 214 residents exposed to seasonal drift containing OP's. We examined 60 individuals (males: 50/60; 83.3%) from the original cohort still residing (more than 40 years) in the same communities. Exposure assessment was based on reports by Israeli institutions and the Bureau of Statistics. Information on personal status, work experience, exposures and symptoms was collected by questionnaires. The nervous system was systematically studied, evaluating cortical upper motor neurons, corticospinal tracts, lower motor neurons and peripheral nerves. Electrophysiological studies included conduction velocities, amplitudes and distal latencies of sensory and motor median, ulnar, tibial and sural nerves; F-waves for proximal nerve functions; thermal and pain thresholds for small thinly-myelinated and non-myelinated fibers; transcranial magnetic stimulation for large fibers. Clinical and electrophysiological features of Carpal Tunnel Syndrome were found in 18% of the subjects, atypically in males only. Fingertips' tingling correlated with both axonal and myelin-dependent parameters (lower wave amplitudes and prolonged latency periods, respectively) in the sensory median nerves bilaterally. OP exposure significantly correlated to prolonged distal latency in the right median sensory nerve (r=0.29; p=0.052; n=45) and lower wave amplitude in the right sural nerve (p=0.031). These findings attest to subtle, predominantly sensory peripheral polyneuropathy following lifetime low-level exposures to drifts containing OP.

Working conditions and fatigue in professional truck drivers at Israeli ports.

BACKGROUND: Trucks represent 6% of all vehicles, but truck crashes account for 20% of road deaths in Israel, even though travel distances are usually short (<200 km) and overnight travel is uncommon. OBJECTIVE: To determine occupational and individual predictors of fatigue, falling asleep at the wheel, and involvement in crashes with injuries and deaths in truck drivers. SETTING AND METHODS: We carried out field interviews of 160 port truck drivers regarding driver characteristics, workplace and driving conditions, employer-employee relations, medical conditions, sleep quality and fatigue, falling asleep at the wheel, and involvement in road crashes. RESULTS: One day before interview, 38.1% of the drivers had worked more than the 12 hour legal limit. More than 30% reported falling asleep at the wheel recently, and 13% had prior involvement in a sleep related crash. Sixty seven (41.9%) drivers said that their employer forced them to work beyond the legal 12 hour daily limit. Involvement in a crash with casualties was associated with poor sleep quality (adjusted OR = 2.9; p = 0.042) and frequent difficulty finding parking when tired (OR = 3.7; p = 0.049). Self assessment of fatigue underestimated fatigue from the Pittsburgh Sleep Quality Questionnaire. However fatigue occurred in many drivers without sleep problems and many crashes occurred without fatigue. CONCLUSIONS: Prevention requires measures to reduce work stresses, screening drivers, speed control, and modal shifts. The work risks and adverse outcomes of truck drivers in large countries with long overnight journeys occur in a small country with small distances, relatively short work journeys, and little overnight travel.

Cellular telephones and effects on the brain: the head as an antenna and brain tissue as a radio receiver.

Headache and other neuropsychological symptoms occur in users of cellular telephones, and controversy exists concerning risks for brain cancer. We hypothesize these effects result from the head serving as an antenna and brain tissue as a radio receiver. The frequencies for transmission and reception by cellular telephones, about 900 MHz for analog and 1800 MHz for digital transmission, have wavelengths of 33-35 and 16-17 cm, respectively. Human heads are oval in shape with a short axis about 16 to 17 cm in length. Near the ear there will be a cross-section in the head with an axis half the wavelength of RF/MW transmissions of 900 MHz and equal to the wavelength of RF/MW transmissions at 1800 MHz. Therefore, the human head can serve as a lossy resonator for the electromagnetic radiation emitted by the cellular telephone, absorbing much of the energy specifically from these wavelengths. Brain cells and tissues demodulate the cell-phone's audio frequencies from the radio frequency carrier. Low audio frequencies in the ranges of alpha and beta waves affect these waves and thereby influence brain function. These effects state the case for a precautionary policy.

Amyotrophic lateral sclerosis in a battery-factory worker exposed to cadmium.

A 44-year-old patient died from amyotrophic lateral sclerosis (ALS) after nine years of heavy exposure to cadmium (Cd) in a nickel cadmium (Ni-Cd) battery factory. Two years after starting work he and co-workers had experienced pruritus, loss of smell, nasal congestion, nosebleeds, cough, shortness of breath, severe headaches, bone pain, and proteinuria. Upper back pain and muscle weakness progressed to flaccid paralysis. EMG findings were consistent with motor neuron disease. Cd impairs the blood-brain barrier, reduces levels of brain copper-zinc (Cu-Zn) superoxide dismutase (SOD), and enhances excitoxicity of glutamate via up-regulation of glutamate dehydrogenase and down-regulation of glutamate uptake in glial cells. High levels of methallothionein, a sign of exposure to heavy metals, have been found in brain tissue of deceased ALS patients. The effects of Cd on enzyme systems that mediate neurotoxicity and motor neuron disease suggest a cause effect relationship between Cd and ALS in this worker.

Extending the boundaries of the Declaration of Helsinki: a case study of an unethical experiment in a non-medical setting.

To examine the ethical issues involved in governmental decisions with potential health risks, we review the history of the decision to raise the interurban speed limit in Israel in light of its impact on road death and injury. In 1993, the Israeli Ministry of Transportation initiated an "experiment" to raise the interurban speed limit from 90 to 100 kph. The "experiment" did not include a protocol and did not specify cut-off points for early termination in the case of adverse results. After the raise in the speed limit, the death toll on interurban roads rose as a result of a sudden increase in speeds and case fatality rates. The committee's decision is a case study in unfettered human experimentation and public health risks when the setting is non-medical and lacks a defined ethical framework. The case study states the case for extending Helsinki type safeguards to experimentation in non-medical settings.

A review of environmental and occupational exposure to asbestos in Israel.

The case for a total ban on manufacture and use of asbestos products is stated by the history of asbestos use, exposures, and risks in Israel. Manufacture and use of asbestos began in Israel in the 1950s, rising to a peak in the mid-1970s, and dropping gradually thereafter until reaching minimal levels in the 1990s. Following heightened public concern regarding the carcinogenic effects of asbestos products, there were reductions in use, manufacture, and persons exposed. Since the 1960s, asbestos-related diseases have been diagnosed in hundreds patients nationwide, including asbestos workers and users, as well as individuals living proximally to the manufacturing facilities. Exposures to asbestos in place remain, and patients with asbestos-related disease from environmental exposure are expected to appear for at least another 20-30 years. In the 1980s, an advisory committee appointed by the Ministry of Health of Israel outlined a comprehensive approach towards prevention, control, management, and compensation for health risks from asbestos exposures. As certain areas are still contaminated with asbestos waste and as environmental exposure persists, continued and improved medical monitoring and compensation programs are urgently needed in order to reduce the suffering of exposed individuals and their families. The ban on asbestos prevents risks from new exposures, but does not undo the damage from past manufacture, use, disposal, and dumping. In this paper, we review the history of Israel's import and use of asbestos, and the management of occupational and environmental exposures. We also address policy, practice, and the need to protect future victims of asbestos-related disease.

Impact of new highways on road deaths: a case study in risk assessment.

Epidemiologists have generally avoided to assess risk for road deaths from high-speed highways. We examined the validity of the claim that the Trans-Israel Highway, a six-lane 320 km toll road with higher design speed, and raised speed limits (120 kph), will reduce road deaths. We used models showing that death tolls vary with the fourth power of rise in driving speed. Risk assessments was derived from estimates of increase in the highway-induced traffic, the impact of higher speed limits (from 110 to 120 kph) and the so-called spillover effect from speed habituation. We predict a large rise in the number of killed or injured, even if the death risks per vkm is low on the Highway itself. With the Trans-Israel Highway, death tolls--some 550 fatalities per year in 1995, could rise to as high as 900-1000 per year in 2010. Congestion produced by induced traffic will partially offset these effects. By contrast, death tolls from alternative strategies based on sustainable transportation policies could be reduced to less than 300 deaths per year. Risk assessment based on explicitly defined assumptions predicts high death tolls from the nationwide impact of raised speed on the Highway and its connecting roads. There is a need for new frameworks which impose the Code of Helsinki type requirements for the assessment and authorization of social decisions with adverse public health impacts.

Complications from supervised mask use in post-operative surgical patients during the Gulf War.

This is a report of three patients in a surgical ward of a hospital who developed complications seemingly related to the use of full-face-fitting masks associated with the first Scud Missile attack on Israel during the Gulf War. Patient 1 developed atrial fibrillation with an uncontrolled ventricular rate; Patient 2 redeveloped a gastrointestinal hemorrhage; and Patient 3 developed a severe anxiety attack. Each of the three was severely ill prior to the event. Special attention should be given to severely ill patients during such events.

Cancer in ex-asbestos cement workers in Israel, 1953-1992.

A cohort of 3,057 male workers employed in an asbestos-cement plant using 90% chrysotile-10% crocidolite, located in Northern Israel, was followed from 1953-1992 for incidence and mortality from cancer. In the years 1978-1992, the cohort had an elevated risk for all malignant neoplasms combined (n = 153, SIR = 117, ns), lung cancer (n = 28, SIR = 135, ns), mesothelioma (n = 21; SIR > 5000, p < .0001), unspecified pleural cancer (n = 5; SIR = 278, P < .0001), and liver cancer (n = 7, SIR 290, ns). Risks for colo-rectal (n = 19; SIR = 79, ns), bladder (n = 12, SIR 69) and renal cancers (n = 5, SIR 104) were less than expected. Risk for mesothelioma showed a sharp risk gradient with duration of exposure, increasing from 1 per 625 for those employed less than 2 years to 1 per 4.5 workers employed over 30 years. The ratio of mesothelioma to excess lung cancer cases was 2.9 to 1, or 3.6 to 1, if pleural cases of unspecified origin were included; the pleura to peritoneum ratio of verified mesothelioma cases was 20 to 1. This atypically high ratio of mesothelioma to excess lung cancer cases is suggested to be the combined result of high past asbestos exposures in the workers and their low prior risk for lung cancer, and possibly, relatively early smoking cessation in relation to asbestos exposure.

Organochlorine insecticides and PCB residues in fat tissues of autopsied trauma victims in Israel: 1984 to 1986.

Between the 1950s and the 1970s, large quantities of organochlorines were used as insecticides in Israel's cowsheds, causing massive contamination of Israel's milk supply. In 32 of 40 autopsied Israeli trauma victims who died between 1984 to 1986, we found three or more types of organochlorines in adipose tissue, and at least one organochlorine residue in all 40 individuals. The cumulative mean organochlorine levels (ppm) in men and women were as follows: DDE = 5.73 and 4.36; DDT = 0.12 and 0.30; HCB = 0.31 and 0.11; beta-HCH = 0.53 and 0.43; PCB = 0.10 and 0.08, respectively. PCB residue levels in fat tissue were lower than those noted in other countries and below the adverse levels associated with health effects. The cumulative mean organochlorine levels in adipose tissue were higher in men than in women in all cases except for DDT. Mean levels for DDE + DDT combined was higher in older than younger people, and all persons' DDT/DDE ratios were less than 1. The DDE levels in adipose tissue were higher than the levels reported in many other countries during the 1970s, 1980s, and 1990s. Our findings suggest that population-wide exposures to organochlorine insecticides come not only from contaminated milk products but other food products as well. The amounts of organochlorines in adipose tissue are compatible with those found in food residue samples during the same period.

Emergency preparedness and response in Israel during the Gulf War.

We examined the effect of the emergency response on medical and public health problems during the 1991 Gulf War in Israel. On the first day of the conflict, the number of deaths from suffocation, asphyxiation, aspiration, myocardial infarction, cardiac arrest, and cerebrovascular accident increased abruptly, as did the number of sudden deaths associated with the use of tight-fitting masks with filters in sealed rooms. Much of the excess risk for death from cardiorespiratory complications during the first alert may have been a consequence of its duration (140 minutes). Mass evacuation and concrete buildings are believed to have kept the death toll from trauma down, and mask use may have protected against facial and upper-airway injuries. Falls and hip fractures, airway irritation from exposure to bleach, carbon monoxide intoxication from open kerosene heaters in sealed rooms, and self-injection with atropine syringes were also noted. A measles epidemic and increased death rates from automobile crashes were other preventable causes of death. Protection against biological warfare was limited to surveillance of trends for pneumonia and gastroenteritis. Emergency planners failed to anticipate the need for better mask fit, hands-on training in the use of masks, and special guidelines for older persons to prevent deaths from suffocation and other cardiovascular-respiratory problems in the first minutes of use. If masks are to be distributed as a protection against chemical warfare, a simpler model including the use of shrouds for whole-body skin protection might help avoid cardiorespiratory complications. Public health problems not adequately dealt with in the predisaster period are apt to emerge with greater severity during a crisis.

Emergency preparedness and response in Israel during the Gulf War.

We examined the effect of the emergency response on medical and public health problems during the 1991 Gulf War in Israel. On the first day of the conflict, the number of deaths from suffocation, asphyxiation, aspiration, myocardial infarction, cardiac arrest, and cerebrovascular accident increased abruptly, as did the number of sudden deaths associated with the use of tight-fitting masks with filters in sealed rooms. Much of the excess risk for death from cardiorespiratory complications during the first alert may have been a consequence of its duration (140 minutes). Mass evacuation and concrete buildings are believed to have kept the death toll from trauma down, and mask use may have protected against facial and upper-airway injuries. Falls and hip fractures, airway irritation from exposure to bleach, carbon monoxide intoxication from open kerosene heaters in sealed rooms, and self-injection with atropine syringes were also noted. A measles epidemic and increased death rates from automobile crashes were other preventable causes of death. Protection against biological warfare was limited to surveillance of trends for pneumonia and gastroenteritis. Emergency planners failed to anticipate the need for better mask fit, hands-on training in the use of masks, and special guidelines for older persons to prevent deaths from suffocation and other cardiovascular-respiratory problems in the first minutes of use. If masks are to be distributed as a protection against chemical warfare, a simpler model including the use of shrouds for whole-body skin protection might help avoid cardiorespiratory complications. Public health problems not adequately dealt with in the predisaster period are apt to emerge with greater severity during a crisis.

Pesticide use, exposure, and risk: A joint Israeli-Palestinian perspective.

The major predictors of health risk from pesticide exposure are quantity and toxicity of pesticides reaching end-users, field workers, and persons (including children) with casual and indirect exposures to field and food residues, drift, and contaminated groundwater. Past work in Israel and the Palestinian National Authority has documented risks for acute poisoning, daily illness, transient neurotoxic effects, and potential cancer hazards in workers, populations exposed to pesticide drift, and the general population. Risk assessment predicts that reduction in use of agents with high toxicity and pesticide substitution are desired strategies for achieving the largest reductions in risk, but successful implementation and program sustainability depend on maintaining crop yield and increasing farmer earnings. A joint pilot Israeli-Palestinian-NGO program aims to determine whether crop yields and profits can be sustained while reducing pesticide use, promoting integrated pest management, and restricting ecosystem damage. The project involves six components: (1) assessments of health risk and crop yield in relation to pesticide use and exposure; (2) training health-agricultural teams to introduce and evaluate crop growth and managements with reduced pesticide use; (3) tracing and stopping import and trade in banned or restricted pesticides; (4) restricting child labor; (5) promoting information delivery and worker and community right-to-know and right-to-act; and (6) establishing a uniform regional standard for protection of workers and the general public. Preliminary evidence (organochlorines and breast cancer, organophosphates and illness in field workers) indicates that (1) a reduction of use is the foremost determinant of a reduction in health risk; (2) cotton yield can be increased despite a reduction in pesticide use (organophosphates); and (3) a reduction in pesticide use (organophosphates and organochlorines) has to be part of a crop rotation program for food crops timed to seasonal fluctuations in supply, demand, and crop price.

Radon exposures in a Jerusalem public school.

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.