Biomedical subjects
Publications and source records attributed to J Ribak.
This paper describes the personal determinants in health promoting behavior, and, in particular, life style changes. A review is made of internal factors, including personality factors, health beliefs, and health attitudes. Environment factors are also taken into account. Suggestions for future research are proposed.
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Occupational cancer is a result of exposure to carcinogens in the workplace. The critical interaction during the initiation stage of the carcinogenesis process occurs between the ultimate form of a carcinogen and the DNA, resulting in the formation of a DNA adduct or several types of gross structural alterations. Several methods have been developed by which carcinogens can be detected. These methods can be utilized for ambient monitoring of exposure and health surveillance. "Molecular epidemiology" is the combination of epidemiologic and laboratory studies, i.e., monitoring exposure by measuring the DNA adduct. Early detection of occupational cancer is difficult, due largely to the latent period which can be up to 20 years or more. For this reason it is important to develop and improve techniques for early detection of premalignant changes. Israel has numerous workers who are exposed to carcinogens, but has no special legislation concerning the use of carcinogenic substances in the workplace. However, an interministerial committee has published, and is continuing to work on, exposure and safety regulations. Medical surveillance and prevention as well as legislation are necessary to reduce morbidity and mortality from occupational cancer.
Ethylene oxide is a colorless gas that can cause neoplastic disease (leukemia, stomach cancer) in animals and humans. Its mutagenic potential is expressed by chromosome aberrations and sister chromatid exchange, as has been shown in numerous studies of groups exposed to ethylene oxide. The results of our pilot study on the effects of exposure to high levels of ethylene oxide show chromosome breakage in exposed individuals at twice the frequency of the normal population. Although these are preliminary findings, they justify urgent, specific protection from further exposure.
We used measurements of heat stress in the cockpit of Bell 206 and 212 helicopters manned by a crew of two to predict changes in the skin temperatures of 50 pilots over a 1-h ground standby period. Cockpit wet bulb globe temperatures increased from 28.1 +/- 5.6 degrees C to 32.9 +/- 3.9 degrees C over the 1-h ground standby period. Skin temperatures increased from 34.7 +/- 1.1 to 35.4 +/- 1.1 degrees C, while heart rate increased from 79.4 +/- 9.6 to 82.6 +/- 9.8 bpm. Cockpit wet bulb temperatures explained 26.9% of the variance of the increase in skin temperature (P = 0.0002). Wet bulb globe temperatures, discomfort index and dry bulb temperatures did not improve the predictive value of wet bulb temperatures alone. Relative humidity was not significantly associated with the increase in skin temperature. We conclude that wet bulb temperatures predict changes in skin temperature as well as other heat stress indices. Furthermore, despite high cockpit temperatures, pilots experienced only minimal strain during the 1-h ground standby period. Extrapolation of our results to the effects on body temperature of higher degrees of heat stress and physical activity is unwarranted and deserves further study.
The association of low back pain (LBP) with mechanical factors at the workplace is uncertain. Most of the studies on this subject did not examine multiple levels of symptoms and did not take into account both the type of work and the primary activity during work. We studied the annual prevalence, severity and duration of attacks of LBP recorded on a physician-administered questionnaire in 208 workers in a pharmaceutical factory. Symptoms were then cross-tabulated with job type, location, work requirements, gender, and years at the factory. LBP was reported by 138 (66.3%) of the workers. Although over 75% of jobs in the packing department, laboratories and offices required prolonged sitting, LBP was most prevalent among workers in the packing department, where the chairs were found to be ergonomically unfit (odds ratio 3.7, 95% confidence interval 1.5-9.1, P = 0.003). Logistic regression demonstrated a highly significant and independent association between LBP and work in the packing or production department (odds ratio 2.03), sitting or lifting (odds ratio 1.97) and 6 years seniority (odds ratio 1.64). Gender was not a significant variable. We conclude that among these pharmaceutical company employees, prolonged sitting and work in the packing or production departments were independently associated with LBP. Prospective studies are warranted to substantiate our findings.