Previous research updated the mortality experience of North American synthetic rubber industry workers during the period 1944-1998, determined if leukemia and other cancers were associated with several employment factors and carried out Poisson regression analysis to examine exposure-response associations between estimated exposure to 1,3-butadiene (BD) or other chemicals and cancer. The present study used Cox regression procedures to examine further the exposure-response relationship between several unlagged and lagged, continuous, time-dependent BD exposure indices (BD parts per million (ppm)-years, the total number of exposures to BD concentrations >100 ppm ("peaks") and average intensity of BD) and leukemia, lymphoid neoplasms and myeloid neoplasms. All three BD exposure indices were associated positively with leukemia. Using continuous, untransformed BD ppm-years the regression coefficient (beta) from an analysis that controlled only for age was 2.9 x 10(-4) (p
1,3-Butadiene has been assessed as a Priority Substance under the Canadian Environmental Protection Act. The general population in Canada is exposed to 1,3-butadiene primarily through ambient air. Inhaled 1,3-butadiene is carcinogenic in both mice and rats, inducing tumors at multiple sites at all concentrations tested in all identified studies. In addition, 1,3-butadiene is genotoxic in both somatic and germ cells of rodents. It also induces adverse effects in the reproductive organs of female mice at relatively low concentrations. The greater sensitivity in mice than in rats to induction of these effects by 1,3-butadiene is likely related to species differences in metabolism to active epoxide metabolites. Exposure to 1,3-butadiene in the occupational environment has been associated with the induction of leukemia; there is also some limited evidence that 1,3-butadiene is genotoxic in exposed workers. Therefore, in view of the weight of evidence of available epidemiological and toxicological data, 1,3-butadiene is considered highly likely to be carcinogenic, and likely to be genotoxic, in humans. Estimates of the potency of butadiene to induce cancer have been derived on the basis of both epidemiological investigation and bioassays in mice and rats. Potencies to induce ovarian effects have been estimated on the basis of studies in mice. Uncertainties have been delineated, and, while there are clear species differences in metabolism, estimates of potency to induce effects are considered justifiably conservative in view of the likely variability in metabolism across the population related to genetic polymorphism for enzymes for the critical metabolic pathway.
The purpose of the study was to describe the sense of coherence (SOC) of three groups of Finnish polytechnic students (n=287) at the beginning of their studies and to follow it during a period of 3 year amongst the health care students (n=63) of this group. The associations between SOC and smoking, drinking and physical exercise were also studied. The data were collected with a questionnaire which included Antonovsky's (Adv. Nurs. Sci. 1(1983)37) SOC scale. Data analysis was with SPSS statistical software. The students showed a strong sense of coherence at the beginning of their studies. Physical activity was related to the strength of SOC, but no association was found with smoking and drinking. Health care students showed a stronger SOC at the beginning of their studies than the two other groups. During the follow-up focused on the health care students, SOC weakened in 6%, remained unchanged in 65% and strengthened in 32% of the participants. Smoking, drinking and physical exercise showed no association with these changes. Future research should be focused on identifying factors that are related to SOC during education.
The treatment-mix, treatment time, and dental status of 268 male industrial workers entitled to employer-provided dental care were studied. The data were collected from treatment records of the covered workers over the 5-year period 1989-93. Treatment time was based on clinical treatment time recorded per patient visit, and the treatment procedure codes were reclassified into a treatment-mix according to American Dental Association categories, with a modification combining endodontics and restorative treatment. The mean number of check-ups followed by prescribed treatment (treatment courses) during the 5 years was 3.7 among those who had entered the in-house dental care program prior to the monitored period (old attenders). Their treatment time was stable, 57-63 min per year, while the first-year mean treatment time (170 min) of those who had entered the program during the study period (new attenders) was significantly higher (P
This study documents the radiation doses received by all in-room personnel of three cardiac catheterization laboratories where more than 15,000 cardiac procedures have been performed over a 5-y period. It is shown that all in-room personnel was exposed to a body dose equivalent well below any regulatory limits. However, some workers may have exceeded the occupational 150 mSv y-1 recommended limit for the lens of the eye. The physicians-in-training and the staff physicians are the two groups more likely to reach this limit. It is also demonstrated that a low correlation exists between the annual number of procedures and the annual head dose equivalent of a physician, but more variation is likely to originate from his/her working attitude and techniques. The mean dose equivalent at the collar level of the physicians is estimated to be 0.04 +/- 0.02 mSv per procedure.
Occupational skin diseases (OSDs) often have considerable medical and occupational consequences. Previous data on prognostic factors have been derived from studies with fairly small sample sizes.
To determine the medical and occupational outcome in 1048 patients diagnosed with OSD at the Finnish Institute of Occupational Health and to identify the prognostic risk factors for the continuation of OSD.
Patients examined in 1994-2001 filled out a follow-up questionnaire 6 months after the diagnosis. Data on atopy, contact allergies, and occupation were analysed.
Six months after the diagnosis the skin disease had healed in 27% of the patients. The OSD had cleared up in 17% of those with no changes at work, and in 34% of those who had changed their job/occupation. The best clearing had occurred in the patients with contact urticaria (35%), whereas the healing of allergic (27%) and irritant (23%) contact dermatitis was similar. The risk factors for continuing occupational contact dermatitis (OCD) were no changes in work, age > 45 years, food-related occupations, respiratory atopy, and male sex.
The healing of OSD was associated with discontinuation of the causative exposure. A change in work and the presence of easily avoidable work-related allergies were associated with a good prognosis.
Ten cases of angiosarcoma of the liver among vinyl chloride workers from a plant in Shawinigan, Québec, are reported. The author insist mostly on the occupational history of these workers and on the morphologic description of the lesions. A pathogenic hypothesis is submitted.