Chemical Worker's Lung Publications (9)
Chemical Worker's Lung Publications
The greatest number of cases occurred in 1997 (10 cases), of which men constituted 58.3% (42 cases) and women 41.7% (30 cases). The most prevalent cases were farmer's lung (50 cases), malt worker's lung (7 cases) and chemical worker's lung (6 cases). Agriculture was the most common economic activity (total 48 cases), with cattleman and dairyman (total 26 cases) the most frequent occupations; less common were tractor driver (8 cases) and maltster (7 cases). Typical case reports after different exposures are presented. A peak in frequency was observed in the age groups of 45-49 and 50-54 yr (20.8% and 19.4% of cases, respectively) and within the first four years of employment (22.2% of cases). Median age was 48 yr and median exposure 12.5 yr. Incidence was in the range of 0.00-0.20 per 100,000 workers, which appears rather low. Due to the difficult diagnostics of hypersensitive pneumonitis, the actual number of cases is undoubtedly higher, and this disease is probably under-reported.
4103: 1,975 cases), silicosis/coal worker's pneumoconiosis (occupational disease no. 4101: 1,158 cases), obstructive airway diseases due to allergens (occupational disease no. 4301: 935 cases), chronic obstructive bronchitis and/or emphysema in hard coal miners (occupational disease no. 4111: 414 cases), obstructive airway diseases due to irritants and toxic agents (occupational disease no. 4302: 181 cases), diseases caused by ionising radiation (171 cases), diseases due to isocyanates (occupational disease no. 1315: 55 cases), and 22 cases of other rare occupational lung and airway diseases. Miners, bakers, chemical workers, hairdressers and health care workers are mostly affected. Bakers were also frequently affected by occupational asthma in Finland, France, Sweden, the United Kingdom, the Piedmont region in Italy, South Africa, and New Zealand. Further, high frequencies of occupational asthma were reported for health care workers in France, Italy, New Jersey, Michigan, and South Africa.
Despite completely different legal definitions and regulations, comparably high numbers of occupational obstructive diseases in western countries require better primary and secondary prevention in industries with high incidence, especially in bakeries, the health care sector, farming, and mining. Furthermore, there is a urgent need for harmonization of recognition and compensation systems for occupational diseases as well as of respective preventive strategies within the European Union.
Mechanistic studies continue to provide a window into pathogenesis and some hope for understanding dose-response relationships at the lower levels seen in contemporary Western workplaces and the general environment. Changes in clinical assessment based on use of new chest imaging techniques beyond the traditional plain film are also an area of evolution and begin to challenge B-reading as the definitive tool for noninvasive assessment of disease. Public health concerns have to a great extent been transported to the developing world where there is a strong trend toward increased use of asbestos, although it has been virtually eliminated from commerce in most developed countries. For nonasbestos fibers, the major unsettled issues are their relative potencies as carcinogens for the human lung and mesothelium and the need to sort out the relation between physical and chemical properties of these fibers and their pathogenicity. The recent discovery of "flock worker's lung" due to synthetic fibers once again alerts us to emerging diseases associated with new technologies.
Materials describing the study results were sent to 15,958 subjects who were notified of their increased risk of arteriosclerotic heart disease, bladder cancer, lung cancer, melanoma, kidney dysfunction, laryngeal cancer, all cancers combined, or soft tissue sarcoma. Workers provided feedback via telephone calls, and for three notifications, by postcards containing workers' comments and ratings of the notification materials. The percentage of telephone calls received from notified workers ranged from 0.3% to 3.8%, and the percentage returning postcards ranged from 8.8% to 17.6%. The two largest categories of callers were those with questions about their disease risk (30%) or who reported on their health status (25%). Most of the comments on postcards (26%) were complimentary or expressed appreciation for receiving the letters; reports of ill health were second (20%). A majority (66%) rated the notification materials well done. Few of the callers (5%) requested information on legal issues. Most (85%) did not find the materials, which ranged in reading level from sixth to ninth grade, too hard to read, although 15% reported difficulty reading them. Although this response system was effective in producing some input from workers, its limitation is that respondents may not be representative of all notified workers. However, such information is useful because there are few data on the effects of notifications on workers.
The following results were obtained from the survey. 1. Both the Dz and MHb values tended to become lower between 1987 and 1993. 2. The MHb levels of the workers were a little higher than the control levels, and the difference between the values was statistically significant (p < 0.01); both levels were, however, within the normal range. 3. The MHb value was estimable from a mathematical model: MHb = (k1-k2/a) x DU x CH, where k1 and k2 were constants and a, DU and CH indicated the activity of glutathione S transferase in erythrocytes (GST), DZ in urine and blood hemoglobin concentration, respectively. The correlation coefficient of the multiple regression was statistically significant (R2 = 0.263, p < 0.01). This model suggests that the biotransformed fraction of ANA in the pulmonary uptake site, the lung, could not penetrate into erythrocytes or act as an MHb former. The model seemed to be consistent and valid when urinary DZ values were less than 1.0 (mg/mg creatinine) and MHb values were less than 2.0 (mg/ml blood). Thus, the upper limit of normal levels for MHb can be considered to be 2.0 (mg/ml blood), or 12-1.6% of total hemoglobin in blood. 4. The significance of the uptake sites, i.e., lung, skin etc., was discussed with reference to the evidence obtained from the longshoremen cases, who were percutaneously exposed to chloronitrobenzene in 1984. 5. Hemolysate solutions from the blood of workers were applied to isoelectric focusing electrophoresis (IEF), and Hb species of different valencies were separated; intermediate MHbs, where the heme iron in one of the components of Hb, i.e., in the alpha or beta chain was oxidized and MHb where both the alpha and beta chain heme iron oxidized and Hb X and Y, were separated and easily discernible. The correlation matrix was calculated using the data relevant to IEF and other indicators; MHb estimated spectrophotometrically, GST activity of erythrocytes, Hb and urinary DZ vale. The statistical procedure of principal component analysis was applied to the matrix, and two major principal components were extracted from the calculation.(ABSTRACT TRUNCATED AT 400 WORDS)
To define whether HLA-DRB may function as a genetic factor for predisposition to coal worker's pneumoconiosis, we determined DRB1, 3, 4, 5 alleles. For this purpose, DRB typing with sequence-specific oligonucleotide probes in 204 German miners with pneumoconiosis and in 52 German miners without pneumoconiosis was used. The miners had worked under comparable conditions. The frequency of DR8 (1*0801-0804) was increased in patients developing pneumoconiosis during the first 15 years of mining (p = 0.047). The frequency of DR1 (1*0101-0103) was elevated (p = 0.022) and that of DR52 (3*0101, 3*0201, 3*0202, and 3*0301) was reduced (p = 0.026) in miners without pneumoconiosis. Our data show that the presence of DR1 and the absence of DR52 support the resistance to coal worker's pneumoconiosis. Furthermore, DR8 may be involved in the rapid development of coal worker's pneumoconiosis.
3% ventilation pneumonitis, 4.1% bird fancier's lung, 2.3% other types, such as chemical worker's lung, and 6.8% of unknown causative agent. It was found that the CD4/CD8 ratios of bronchoalveolar lavage (BAL) lymphocytes were significantly different with the type of disease. The ratio was 0.6 +/- 0.1 (mean +/- SEM) in summer-type HP (N = 271), 4.4 +/- 0.7 in farmer's lung (N = 22), 1.6 +/- 0.3 in ventilation pneumonitis (N = 19), and 2.0 +/- 0.5 in bird fancier's lung (N = 19). In farmer's lung, the CD4/CD8 ratio in smokers was 6.2 +/- 1.9 (N = 6) in contrast with 3.4 +/- 0.7 for nonsmokers (N = 16) (p less than 0.05). It has been generally considered that the phenotypes of BAL lymphocytes in patients with HP are predominately CD8 cells. Our present results, however, indicate that the phenotypes of BAL lymphocytes vary with the type of HP, probably depending on factors such as causative agent, smoking, or staging of the disease.