Dietary and clastogenic factors in children who immigrated to Israel from regions contaminated by the Chernobyl accident.

The authors evaluated the possible association between dietary history and plasma clastogenic factors in children who immigrated to Israel between 1989 and 1993 from regions contaminated by the Chernobyl accident. The authors compared questionnaire data about demographic variables, dietary histories before and after immigration occurred, and health status with clastogenic factor scores for 162 immigrants. Logistic regression analysis revealed a negative association between clastogenic factor scores and frequency of consumption of fresh vegetables and fruit among children < or = 7 yr of age during the postimmigration period. Intake of eggs and fish by boys who were < or = 7 yr of age prior to immigration was associated positively with clastogenic factor scores. Consumption of fresh vegetables and fruits afforded protection to the immune systems of children who were < or = 7 yr of age.

A case-control study of Parkinson's disease in urban population of southern Israel.

BACKGROUND: In recent years, an increased prevalence of Parkinson's disease (PD) in southern Israel was observed. The aim of this study was to determine which exposures are associated with PD in the urban population of this region. METHODS: Ninety-three PD patients living in towns were compared to 93 age and sex matched controls. A previously validated questionnaire, including demographic data, education, data on exposures, previous diseases, family history and habits, was administered. RESULTS: In multivariate logistic regression analysis, it was found that history of work in construction sites was the strongest predictor of PD risk, followed by exposure to pesticides. In contrast, there was a negative association with smoking and history of mechanical factory employment. When the same statistical analysis was limited to association of PD with smoking, pesticides and construction work, the latter was found to be the strongest risk factor. CONCLUSION: The risk factors for PD in this population are work on a construction site and exposure to pesticides.

Case-referent study on occupational risk factors for bladder cancer in southern Israel.

OBJECTIVE: To evaluate the possible association between occupational exposures (risk factors) and male bladder cancer in the Negev region (southern Israel) to enable preventive strategies to be applied. METHODS: A total of 92 male bladder cancer patients, diagnosed at a regional medical center between 1989 and 1993, were studied by interview and compared with 92 males without oncological disease after matching by age and country of origin. A special questionnaire was developed to gather information on demography, life-time occupational history, smoking habits, coffee consumption, and health status. Statistical analysis of the case-referent data was done using the SPSS-5 package for performance of the chi-square test, conditional logistic regression, and multiple classification analysis. RESULTS: Significant associations were found between bladder cancer occurrence and (1) three different groups of occupational exposures [a - solvents (P = 0.002, OR not computed due to the lack of exposed persons among referents), b - dusts (P = 0. 02; OR = 4.67), and c - exposure to multiple chemicals (P < 0.001, OR = 6.25); (2) nephrolithiasis (P = 0.02, OR = 11.00); and (3) cigarette smoking (P = 0.01, OR = 1.87). CONCLUSIONS: Certain types of occupational exposure, different from that to aromatic amines and dyes, may be considered as contributing factors in the epidemiology of bladder cancer. Better identification of these chemicals and the work processes where they are used may help in abating such exposures, thus leading to a reduction in the risk for this relatively common cancer.

Juvenile hypothyroidism among two populations exposed to radioiodine.

We found an epidemic of juvenile hypothyroidism among a population of self-defined "downwinders" living near the Hanford nuclear facility located in southeast Washington State. The episode followed massive releases of 131I. Self-reported data on 60 cases of juvenile hypothyroidism (<20 years of age) among a group of 801 Hanford downwinders are presented, as well as data concerning the thyroid status of approximately 160,000 children exposed to radioiodine before 10 years of age as a result of the 26 April 1986 Chernobyl explosion in the former Soviet Union. These children were residents of five regions near Chernobyl. They were examined by standardized screening protocols over a period of 5 years from 1991 to 1996. They are a well-defined group of 10 samples. Fifty-six cases of hypothyroidism were found among boys and 92 among girls. Body burdens of 137Cs have been correlated with hypothyroidism prevalence rates. On the other hand, the group of juvenile (<20 years of age) Hanford downwinders is not a representative sample. Most of the 77 cases of juvenile hypothyroidism in the Hanford group were diagnosed from 1945 to 1970. However, the ratio of reported cases to the county population under 20 years of age is roughly correlated with officially estimated mean levels of cumulative thyroid 131I uptake in these counties, providing evidence that juvenile hypothyroidism was associated with radioiodine exposures. Because even subtle hypothyroidism may be of clinical significance in childhood and can be treated, it may be useful to screen for the condition in populations exposed to radioiodine fallout. Although radiation exposure is associated with hypothyroidism, its excess among fallout-exposed children has not been previously quantified.

Cancer incidence and risks in selected agricultural settlements in the Negev of Israel.

Medical staff of two Negev kibbutzim invited epidemiologists to help them investigate cancer rates among their members. Our objectives were (a) to determine whether the cancer rate in the kibbutzim was elevated or abnormal and (b) to determine the role of agricultural and other relevant exposures if cancer incidence was elevated. We validated cases of cancer by kibbutz records and by surveying other information; we computed expected values on the basis of the age-sex-calendar period and site-specific cancer incidence rates reported by the Israel Cancer Registry for the entire population; and we compared the data for the 2 kibbutzim with data derived for similar age and sex groups in 2 other kibbutzim, which were assumed not to have increased cancer rates. In addition, we planned and conducted a case-referent study, including the design, pretest, and use of questionnaires, including data about lifetime exposures (i.e., type of work and its duration, agricultural and industrial chemicals, smoking and alcohol use, demographic variables, health experiences, and family history). In only one of the kibbutzim, for which high cancer rates were suspected, was there significant excess for all sites in persons who were less than 40 y of age. In one of the "comparison" kibbutzim, we found increased cancer rates overall. Much of the excess in the high cancer kibbutzim was in hematological cancer (i.e., leukemia and lymphoma). Multiple years of work in fields, orchards, and landscape, as well as orchard work that commenced before 1960, were associated with increased risk of cancer (p < .08). We also found an association between cancer rate and numbers of industrial chemicals used (p < .08). Pipe and cigarette smoking were also associated with increased cancer incidence. In the multivariate analysis, the association with calendar year in which orchard work was started and multiple exposures to industrial chemicals was stronger than associations noted in the univariate analyses. Although duration of agricultural work or multiple industrial exposures were clearly associated with increase in cancer risk, we were unable to identify the causal role of specific agent(s). Nonetheless, educational programs for cancer prevention can be based, in part, on the results of such a study.

A case-referent study of extrapyramidal signs (preparkinsonism) in rural communities of Israel.

BACKGROUND: In previous studies we reported an increased prevalence of Parkinson's disease in several kibbutzim of Southern Israel (cluster kibbutzim). Subsequent studies revealed a significant prevalence of subjects presenting extrapyramidal signs (preparkinsonism) in the same kibbutzim. On follow-up worsening of these signs was observed in some of the older subjects, some of them actually being diagnosed as suffering from 1-Dopa responsive Parkinson's disease. The current study was designed to evaluate possible etiologic factors for the development of preparkinsonism. METHODS: 317 subjects over the age of 40, living in five kibbutzim were examined and interviewed. 95 subjects presenting extrapyramidal signs were compared with 95 control subjects. They were matched for age, sex and length of residence in the kibbutz. Odds ratios were computed to identify exposure variables for logistic regression analyses. Detectors for carbamates and organic phosphates were applied at different sites of these kibbutzim. RESULTS: The severity and frequency of the extrapyramidal signs were higher in the older age groups, more in the "cluster", than in other kibbutzim. A very strong association was found between field crop work exposure, particularly cotton, and preparkinsonism (p = 0.0007) and a slightly weaker association for landscape work. The detectors picked up abundant pesticide traces (carbamates and organic phosphates) in the residential areas fairly distant from sites of aerial spray. CONCLUSIONS: We assume a chronic passive exposure of the residents in these kibbutzim to pesticides, in addition to any occupational exposures.

Dynamics of parkinsonism-Parkinson's disease in residents of adjacent kibbutzim in Israel's Negev.

From serial studies of clinical findings and Webster's scores, we determined the incidence of Parkinson's disease and the pattern of progression of the components of parkinsonism in residents older than 40 in rural settlements with unusually high rates of Parkinson's disease in southern Israel (Negev). In 1988, the authors reported on three adjacent kibbutzim at which were identified 13 cases of Parkinson's disease in a population of 413 persons older than 50 years. In the region as a whole, there were 143 additional cases among a population of 64,185 who were 40 years of age or older. The age-standardized prevalence ratio for the kibbutz population was 5.43. By 1993, 2 of the persons with Parkinson's disease had died, and 8 new cases had been diagnosed. The age-standardized prevalence ratio in 1993 was 8.09. The crude incidence ratio for persons older than 40 was 3.4 per 1000 per year. Webster's score is used as an estimator of the severity of pre-parkinsonism. In the normal population of elderly persons from other areas in the Negev, only 20 of 110 had a score greater than 0 (11, 8, and 1 scored 1, 2, and 3, respectively). When the Webster's score was first applied systematically-in 1989 to asymptomatic persons from the kibbutzim who were older than 40-46 of 104 had scores of 2 or more, and some subjects also had impaired vibration sense. The tests were repeated by different observers on a casual sample in 1991 and 1993. Of the persons older than 60 in 1989 (n = 14), the scores increased from an average of 2.3 in 1989 to 3.9 in 1991 and to 5.7 in 1993. In a younger sample (n = 7), the mean scores were 2.3 in 1989, 3.6 in 1991, and 2.9 in 1993. These results are evidence of an age-specific peak in incidence and prevalence in the 70- to 79-year-old age group and may represent a cohort exposure phenomenon. The results may also reflect the critical role of age in the transformation of pre-parkinsonism to Parkinson's disease. Finally, in this population with high initial rates of Parkinson's disease, there was evidence of pre-parkinsonism in about half of those older than 40, and active progression of pre-parkinsonism in those older than 60. Therefore, this group is an ideal population to test for effects of preventive interventions.

Chemical exposures and Parkinson's disease in residents of three Negev kibbutzim.

We consider whether chemical pollutants in drinking water (including aromatic hydrocarbons, alkanes, halogenated aliphatic hydrocarbons, and phthalic acid) or used occupationally in agriculture that have shown no parkinsonism-inducing effect may be responsible for excess cases of Parkinson's disease (PD) in three adjacent kibbutzim in southern Israel (Negev). Literature data on PD pathogenesis have been compared with common pathogenetic pathways to xenobiotics effects; the following neurotoxic mechanisms, besides individual sensitivity, have been suggested: (1) impairment of the protective role of the substantia nigra against toxicants by binding of chemicals to melanin; (2) oxidative stress induction, including glutathione reduction, impaired calcium metabolism, and alteration of cytochrome P-450 activity; (3) blockade of iron chelators because of structural similarities to them or their precursors; (4) mediation of the production of endogenous dopaminergic neurotoxins, such as trichloroharmanes or isoquinolines; (5) blockade of dopamine receptors because of their resemblance to chemicals with affinity to these receptors; (6) stimulation of prostaglandin-H synthase and monooxygenase activity; and (7) stimulation of autoimmune processes and creation of autoimmunity to structures of the dopaminergic system caused by chemical similarity.

Blood pressure among immigrants to Israel from areas affected by the Chernobyl disaster.

OBJECTIVES: To validate and analyze apparent association of hypertension with exposures to radiation at Chernobyl among immigrants to Israel from the contaminated areas. METHODS: Data were collected in 1991 and 1994 from two samples of persons who immigrated to Israel from the contaminated zone around the Chernobyl nuclear power plant. The first sample were self-referred for evaluation in a clinic by whole-body cesium measurement, physical examination, and questionnaire (N = 756, 328 from less exposed and 438 from more exposed areas). The second wave data were collected in 1994 during home interviews for evaluation of psychosocial factors associated with their experience (N = 708, 121 from more exposed and 253 from less exposed areas). In the second study a referent group was included (n = 334) who were matched by age, sex, and year of immigration who immigrated from other areas outside of the contaminated zone. Estimates of exposure were based on the IAEA map of ground-level cesium isotope (137Cs) contamination. RESULTS: In the 1991 sample, 21% from high exposure areas and 16% from less exposed areas had elevated systolic blood pressure (> 140 mmHg). Elevated diastolic blood pressure (> 90 mmHg) had a similar difference between more and less exposed groups (21% and 16%). Age- and sex-specific analyses showed that statistically different levels were found in the older age groups. In the 1994 sample, we confirmed a relationship between exposure and elevated blood pressure. 33% of those from the more exposed areas and 34% of those from less exposed areas had elevated systolic blood pressure, compared with 23% of the comparison group, with a similar trend found in diastolic blood pressure. The relationship between exposure and blood pressure was accentuated in the group of respondents who had high scores on PTSD symptoms. Of the psychological variables analyzed, systolic blood pressure was most strongly related to cancer-related anxiety and somatization. A discriminant function analysis showed that three variables: age, reporting a significant loss from the Chernobyl accident, and fear of cancer correctly differentiated 72% of those with normal and high blood pressure. CONCLUSIONS: There is a relationship between exposure to Chernobyl and high blood pressure, partly due to the psychological reactions to the accident.

Lessons learned from the study of immigrants to Israel from areas of Russia, Belarus, and Ukraine contaminated by the Chernobyl accident.

During the past 6 years, immigration to Israel of 700,000 persons from the former Soviet Union (FSU) included about 140,000 from radiocontaminated regions of Belarus, Ukraine, and Russia near Chernobyl. In Beer Sheva, a major center for immigrant absorption in Israel, a primary objective was to evaluate their health status and to refer them for care. 137Cs levels in 1228 men, women, and children were measured with a portable whole-body counter. Whole-body counts showed clear correlation with the degree of 137Cs ground contamination in previous regions of residence. The population could thus be sub-divided according to degree of exposure, based on previous regions of residence. The thyroid status of 300 local immigrant children was evaluated because of the increased risk of childhood thyroid cancer in the regions from which they came. This group was subdivided into comparative groups of children who came from less and more contaminated areas according to the International Atomic Energy Agency soil 137Cs contamination maps. Enlarged thyroids were found in about 40% of both groups. One 12-year-old girl from Gomel had a malignant papillary carcinoma. Thyroid-stimulating hormone levels, though within normal limits, were significantly greater (p < 0.02) for girls from high exposure regions. Liquidators showed significant increases in serum clastogenic factor and in the number of circulating glycophorin A-mutated red cells. In studies of over 700 people from both radiocontaminated and unaffected regions of the FSU, evidence for posttraumatic stress disorder was found more frequently in persons coming from the more contaminated areas.

Health effects in a casual sample of immigrants to Israel from areas contaminated by the Chernobyl explosion.

We analyzed questionnaire and physician examination data for 1560 new immigrants from the former USSR divided into three groups by potential exposure to Chernobyl radiation. Two groups were chosen according to soil contamination by cesium-137 at former residences, as confirmed by our findings in a 137Cs body burden study. The third group consisted of "liquidators," persons who worked at the Chernobyl site after the disaster. Liquidators had greater self-reported incidences of symptoms commonly accepted as acute effects of radiation exposure, increases in prevalence of hypertension, and more health complaints. Excesses of bronchial asthma and health complaints were reported in children from the more exposed communities. Asthma prevalence in children potentially exposed in utero appears to be increased eightfold. Older adults from more exposed areas had more hypertension as assessed by history and measurements. These findings suggest the possible association of radiation exposure with several nonmalignant effects.

Radiocesium body burdens in immigrants to Israel from areas of the Ukraine, Belarus and Russia near Chernobyl.

Of the 500,000 immigrants from the former Soviet Union who came to Israel during 1990-1993, about 100,000 are estimated to have come from radiocontaminated areas near Chernobyl. These people were subject to chronic uptake of environmental radiocesium over protracted periods. During October-November 1991, a joint Israeli-Canadian investigation measured radiocesium body burdens in immigrants to Israel from the Ukraine, Belarus, and the southern Russian republic in order to provide factual information on radiocesium levels to concerned immigrants and to relate the body burdens to the geographic area of residence before coming to Israel. Assessments were made of 137Cs body burdens in 1,228 volunteer men, women, and children. These measurements were accompanied by medical assessments based on clinical histories and examinations. Radiocesium levels were strongly dependent on the duration of residence in Israel, with the highest levels being found in the most recent immigrants. The maximum level, extrapolated back to the time of leaving the former Soviet Union, was estimated to be about 0.83 kBq (10.3 Bq kg-1). Of the most recent immigrants from the Kiev region (< 101 days in Israel), only 15% had back extrapolated body burdens > 50 Bq, whereas 53% of those coming from Gomel and other towns in the contaminated zones (> 3.7 x 10(10) Bq km-2 of radiocesium) had detectable levels > 50 Bq. People coming from the latter region had significantly higher body burdens as compared to those from the former, in accordance with the higher degree of ground radiocesium contamination reported for the latter region. Women and children showed considerably lower total radiocesium content in comparison to men. All radiocesium body burdens at the time of measurement were too low to be of health concern.

Why dose-response relationships are often non-linear and some consequences.

Given the dependence of many risk assessments on the assumption of linearity of dose-response relationships in human populations, we analyze the circumstances likely to lead to non-linearity and test our hypothesis of the high prevalence of non-linearity by examination of recent literature. METHODS. The analysis of Bross, based on whether irradiated cells die or can manifest malignancy, leads him to generalize that if a single exposure can have one of two (or more) countervailing outcomes, non-linearity of dose-response will result. We list four other common mechanisms which would have similar effects: symptom-stimulated withdrawal from exposures to respiratory irritants; certain aspects of the "healthy worker effect" (especially its obverse-withdrawal from the work force due to illness); selected consequences of the competing risks of long-term disease; and shift in relative strength among multiple independent variables. We then examine recent literature to see how often reports of linear, monotonic, and non-monotonic dose-response relationships occur and discuss the likelihood of countervailing alternate outcomes in selected examples. RESULTS. Non-linear and linear relationships are about equally frequent. Under circumstances where countervailing outcomes are probable, dose-response relationships should be non-linear and often are. These conditions may also lead to non-linear difference equations, which may manifest "chaotic" attributes. CONCLUSIONS. Regulations and policies cannot be routinely derived on the basis of extrapolating linear dose-response relationships for human populations. Although our analysis is oriented principally to epidemiology, similar considerations apply to toxicological studies as well.

[Contribution of petroleum-processing plants to the total level of atmospheric air pollution]. / Vyiavlenie vklada predpriiatiipo dobyche i pererabotke nefti v obshchii uroven' zagriazneniia atmosfernogo vozdukha.

On the basis of results of field studies the means to reveal the contribution of oil extracting and processing enterprises (the main components of discharges are similar to the common prevalent impurities in the air of residential areas) into the total level of ambient air pollution has been developed. The method takes into account the relationship between average annual concentrations of oil hydrocarbons and carbon oxide.

[Method of the detection of sulfur dioxide in the work zone air]. / Sposob opredeleniia dioksida sery v vozdukhe proizvodstvennykh pomeschenii.

The contributors set forth a newly developed potentiometric technique for detecting SO2 in the working zone air in the absence of other acid-producing compounds. The proposed model curve, which was designed with a SO2 containing teflon ampulla makes it possible to determine the SO2 concentration against the registered pH level.