Occupational contact dermatitis due to epoxy resin in a fiberglass binder.

Eight workers handling fiberglass coated with uncured epoxy resin, out of a population of approximately 130 workers, developed dermatitis of their hands and forearms. Four also had involvement of the head and neck. Epicutaneous testing established the presence of contact allergy to epoxy resin in six, and one worker had continuous sensitivity to cresylglycidyl ether. Workers handling the coated material after it had been heat-cured were not affected, even if they had had problems with dermatitis while handling the uncured coated fiber.

Respiratory health assessment by questionnaire of 2024 workers involved in man-made mineral fiber production.

A respiratory health questionnaire was administered to the workers producing man-made mineral fibers in three glasswool and two rockwool plants in France, in order to detect adverse effects resulting from fiber exposure. The mean ages of the 2024 male participants ranged from 32 to 41 years. The standardized questionnaire was filled in by the industrial physicians: occupational history, smoking habits, respiratory symptoms (cough, phlegm, dyspnea, asthma), irritative complaints of the upper airways (nasal fossae and sinuses, pharynx and larynx) were all recorded. Multiple unconditional logistic regression was used to test for a relationship between possible explanatory variables and these symptoms. The prevalence of respiratory symptoms (cough, phlegm, dyspnea) was strongly correlated with age and increased markedly among current smokers. Having adjusted for these confounding factors, significantly elevated Odds Ratios (ORs) for cough and phlegm were observed among the workers of one plant (51% of the whole study population) who had been exposed to fibers for a long time. In the same plant, the ORs for complaints of nasal fossae and sinuses increased significantly with the duration of fiber exposure, and one elevated OR was observed for pharyngeal and laryngeal symptoms. These findings were not consistent with the results observed in the four other plants (49% of the study population), since ORs for all these symptoms were either low or not significantly increased according to the duration of fiber exposure. This lack of similarity among plants could be explained either by differences in interviewers, age, seniority and tobacco consumption, or by secular changes in the industrial processes involved.(ABSTRACT TRUNCATED AT 250 WORDS)

Glass fibre irritation and protective creams.

5 commercial products were tested pairwise as prophylaxis against itching and irritation from glass fibres: a commercial cream for glass fibre itching, a silicone spray, an emollient cream, a fatty ointment, and a "cream-ointment". The preparations were found to have very limited value in protection against glass fibre irritation. Some workers even experienced exacerbated itching from all the preparations, including the cream marketed for protection against glass fibre irritation. Only 25% of a group of workers with severe glass fibre itching still used an emollient cream after 12 weeks.

Industrial airborne irritant or allergic contact dermatitis.

Industrial airborne irritant or allergic contact dermatitis is commonly observed in many factories. Examples of airborne irritants include fibres (such as fibreglass or rockwool), various kinds of dust particles (such as cement, slag, sludge, insulating foam, wood chips), acids and alkalis, gasses and vapours. Airborne contact allergens are unequivocally numerous. The clinical symptoms of both irritant and allergic airborne contact dermatitis are reviewed.

Comparative epidemiology of men exposed to asbestos and man-made mineral fibers.

Comparative analyses are presented of selected studies of long-term reactions to occupational exposures to asbestos and man-made mineral fibers (MMMF), with emphasis on studies with dose-response information and long enough period of follow-up to observe lung cancer excess, if it occurred. Uniform dose estimates based on average number of fibers per milliliter were derived and tabulated with the corresponding standard mortality (or morbidity) ratio (SMR), crude probability for each unfavorable outcome, and the likelihood that at least as many deaths would have occurred as a result of the expected numbers under Poisson assumptions. A dose-response relationship was said to have been indicated when the crude probability increased monotonically with dose and/or the Poisson probability decreased and reached a value of less than 0.05. Some arbitrary assumptions had to be made in estimation of the dose, and they may need to be corrected. Gravimetric dose estimates may have given different results. Studies selected for analysis included Quebec asbestos miners and asbestos cement workers exposed to asbestos, and pooled U.S. and European studies of MMMF workers, as well as a sample of cigarette-smoking fiberglass workers whose X-ray films were evaluated for fine nodular or irregular opacities. The lowest dose capable of showing either a statistically significant excess (single point criterion--SP) or the median dose in an apparent dose-response relationship with cause of death or radiological results is tabulated. Radiological changes show a dose-response relationship for all types, with a median dose for asbestos of 2.8 fibers/ml. For fiberglass workers, the median dose of electron-microscopically detected fibers was two orders of magnitude less. For asbestos SP, exposures of 1.4 to 22 fibers/ml were associated with increased lung cancer, while for mineral wool, the minimal level with significant SP increase in lung cancer was an order of magnitude less. Based on fiber or particle counts, man-made mineral fibers appear to be more potent than asbestos with regard to chronic pulmonary disease.

Glass fiber dermatitis.

Many workers exposed to glass fibers experience an intense pruritus (itching), sometimes accompanied by erythema, erosions, and dermatitis. Patch tests to glass fibers provoked a papulovesicular dermatitis in about 25% of normal persons. Workers in the glass wool industry, whether or not clinically symptomatic, had the same levels of patch-test reactivity. A battery of skin tests failed to identify persons with an increased susceptibility to glass fiber pruritus. Some workers' skin becomes hardened by continuous exposure. This hardening is lost after a one-month holiday but is quickly regained. Barrier creams had no protective value in preventing glass fiber dermatitis.

Mortality and incidence of cancer of workers in the man made vitreous fibres producing industry: an international investigation at 13 European plants.

A total of 25 146 workers at 13 plants producing man made mineral fibres (MMMF) in seven European countries (Denmark, Finland, Federal Republic of Germany, Italy, Norway, Sweden, and United Kingdom) were studied in a historical cohort investigation. At 12 of the 13 plants an environmental survey was carried out to determine present day concentrations of airborne man made mineral fibres that showed levels of respirable fibres usually below 1 f/ml and most commonly in the range 0.01 to 0.1 f/ml. Workers were entered into the cohort at the moment of their first employment at one of the 13 factories (which started to operate between 1900 and 1955), and were followed up to at least 31 December 1977. Three per cent of the workers were lost to follow up. National death rates and national cancer incidence rates, where applicable, were used for each of the seven countries for comparison with the workers' cohort. A single death from mesothelioma was reported out of a total of 309 353 person-years of observation. No consistent differences (within and between plants) were noted between observed and expected numbers concerning individual causes of death or individual cancer sites, apart from lung cancer. For this cause a tendency was observed for the standardised mortality ratio (SMR) to increase with time from first employment. When the data from all the plants were pooled a statistically significant raised SMR of 192 (17 observed, 8.9 expected; 95% confidence interval 117-307) appeared in the group with 30 years or more since first employment. The relevance of this finding, to which different factors including uncontrolled confounders such as smoking habits may have contributed, cannot be established at present. The result is suggestive, however, of an increased risk associated with the man made mineral fibres working environment of 30 or more years ago.

Strategies for pooling data in occupational epidemiological studies.

In occupational epidemiology, most of the populations at risk are of limited size, and therefore pooling of the experience of different groups with similar exposure is desirable. We present and compare five different strategies for pooling of such data, including the "default" strategy of present reporting practices, which have the disadvantage that the experience of many small units is not recorded because of the low statistical power of small populations. A simple summation strategy including cases and controls from diverse groups, while attractively simple, may be fallacious when cases and controls have different proportions which are confounded with the risk ratios. Separate summation of observed and expected numbers of cases avoids the risk of fallacy, but may be unduly influenced by the results in one large plant. A "Clinical Trial" type of strategy in which all of the data are collected by a common protocol and therefore considered as a single data set is administratively complex and does not seem well suited for occupational epidemiology. Probability pooling seems to have attractive features, avoiding most of the disadvantages of the other strategies, and having the added feature that weighting for exposure and duration of follow-up can be included. Probability pooling requires exact probability statements for each study. Examples are given for pooling of data from exposures of operating room personnel to anaesthetic agents, cohorts of workers exposed to asbestos, and cohorts of workers exposed to man-made mineral fibres. A working group is proposed to recommend procedures and to assist in interpreting pooling activities.

[Linear dermatitis of the calves. I. Clinical, epidemiologic and histopathological aspects]. / Dermatitis lineal de pantorrillas. I. Aspectos clínicos, epidemiológicos e histopatológicos.

A new form of contact dermatitis that we have denominated "lineal dermatitis of legs' calfs" is described. After presenting its clinical and histopathological characteristics, we analyse the main pathogenic fractures involved which are essentially related to a direct and intimate contact of calfs' skin with the acute border of buses' seats buits with fiber glass. It is believed that both the "dermatosis parasitaria de las butacas" of Quiroga (1959) and the linear women's calf dermatibis by paedherus (Martino and cols., 1979), correspond to the disease detailed in this paper.

A comparison of the effects of exposure of baboons to crocidolite and fibrous-glass dusts.

Epidemiological studies have not revealed any significant health hazards from exposure to fibrous glass and animal experiments have been inconclusive. Baboons exposed to a fibrous-glass dust cloud with size features similar to those of crocidolite asbestos developed focal peribronchiolar fibrosis with scant ferruginous body formation. The lesions were similar to those produced by crocidolite but were less extensive. No neoplasms occurred.