Volatile organic compounds and formaldehyde as explaining factors for sensory irritation in office environments.

This study's database comprised results of volatile organic compound (VOC) measurements from 176 office buildings. In 23 of the 176 buildings, formaldehyde measurements were also conducted. It was suspected that the buildings had indoor air problems, but a walk-through inspection did not reveal any clear, abnormal contaminant sources. The 50 most abundant VOCs and their concentrations in 520 air samples were analyzed. The irritation potency was estimated for 33 out of the 50 common VOCs and their mixtures, as well as for formaldehyde. This information was used to calculate the recommended indoor air levels (RILs) for the VOCs. The RILs were considerably higher than the measured mean indoor air concentrations in the buildings. However, the RIL for formaldehyde was exceeded in most of the 23 buildings studied. According to the evaluation of irritation potency, formaldehyde was a more likely cause of sensory irritation than the mixture of common nonreactive VOCs at the concentrations that occurred in the buildings without abnormal indoor sources. Furthermore, environmental symptoms of office workers were characterized in 20 office buildings (including the database of 176 office buildings) with the aid of an indoor air questionnaire. The most frequent symptoms related to the indoor environment were involved the upper respiratory tract. However, no relationship could be shown between the reported symptoms and the occurrence of VOC and formaldehyde concentrations in these buildings. Generally, the study results indicated that formaldehyde was the more likely agent causing sensory irritation than the mixture of the common nonreactive VOCs at the concentrations occurring in the buildings without abnormal indoor sources.

Incidence of occupational asthma and persistent asthma in young adults has increased in Finland.

To investigate the incidence of occupational asthma and its relationship to new cases of persistent asthma, the data was collected from two national registers which cover practically all new cases of both diseases. In 1986 to 1993, the annual incidence of persistent asthma in adults (from 15 to 64 years) increased from 6,645 to 8,056 (21%). The incidence of asthma in women increased from 3,302 to 4,717 (43%). In the age group of 15 to 29 the increase was 91%, in 30 to 49 it was 60%, and in 50 to 64 the increase was 7%. Among men, the annual incidence remained stable. However, in the age group of 15 to 29 it increased by 87%, in 30 to 49 by 46%, while a decrease of 43% was detected in the age group of 50 to 64 years. During the same period, the annual incidence of occupational asthma increased from 227 to 386 (70%), from 109 to 185 (70%) in women and from 118 to 201 (70%) in men. In 1993 the population in Finland in the age range from 15 to 64 was 2.026 million. Thus, the incidence of persistent asthma was 0.4%. The proportion of newly diagnosed occupational asthma out of all new cases of asthma was 4.8%.

Assessment of indoor air problems at work with a questionnaire.

AIMS: To assess the extent of indoor air problems in office environments in Finland. METHODS: Complaints and symptoms related to the indoor environment experienced by office workers were collected from 122 workplaces in 1996-99 by using the modified Indoor Air Questionnaire established by the Finnish Institute of Occupational Health. Altogether 11 154 employees took part in the survey. RESULTS: The most common problems were dry air (35% of the respondents), stuffy air (34%), dust or dirt in the indoor environment (25%), and draught (22%). The most common work related symptoms were irritated, stuffy, or runny nose (20%), itching, burning, or irritation of the eyes (17%), and fatigue (16%). Women reported indoor air problems and work related symptoms more often than men. Allergic persons and smokers reported indoor air problems more often, and experienced work related symptoms more often than non-allergic persons and non-smokers. CONCLUSIONS: The complaints and work related symptoms associated with indoor air problems were common in office workers. The present questionnaire is a suitable tool for the occupational health personnel in investigating indoor air problems and the data of the survey can be used as a reference when the results of a survey at work are being analysed.

Psychosocial work environment and indoor air problems: a questionnaire as a means of problem diagnosis.

AIMS: To examine the relation between the psychosocial work environment and the perceived indoor air problems measured by a questionnaire survey; and to discuss the role of a questionnaire as a means to enhance collaboration in the challenging multiprofessional process of solving indoor air problems. METHODS: The research material comprises surveys conducted in 1996-99 in 122 office workplaces with 11 154 employees. RESULTS: The association between the psychosocial work environment measured by the Indoor Air Questionnaire (MM-40) and the occupants' complaints concerning indoor air as well as symptoms attributed to indoor air was significant. Those who perceived their psychosocial work environment more negatively had more complaints regarding the indoor environment and more symptoms attributed to the indoor air. The association was detected among both genders, in every age group, among smokers and non-smokers, and respondents with an allergic or a non-allergic background. CONCLUSIONS: Results support the hypothesis that psychosocial factors in the work environment play a significant role in indoor air problems at workplaces. The survey data can be used as a reference database for future studies, and in occupational health care practice when the working conditions of individual workplaces are estimated. The MM-40 could be useful as a practical screening method in field work for analysing the role of the psychosocial work environment among the different background factors of an indoor air problem. However, in order to interpret and evaluate the significance of the results concerning a single workplace, more information on the organisation is needed, as well as cooperation and discussions with the staff. Further studies of the reliability and validity of the psychosocial questions in MM-40 are also needed.

Ultrastructure of extrinsic allergic bronchiolo-alveolitis.

Electron microscopic findings in open lung biopsies of 13 patients with extrinsic allergic bronchiolo-alveolitis (EABA) were studied. Eleven of the patients had farmer's lung and two had been exposed to other mouldy dust. Numerous lymphocytes, macrophages and giant cells were found both in the alveolar and bronchiolar lumina. Bronchiolar changes included loss of microvilli on the ciliated cells, granulomas, detachment of basal cells from each other, as well as disintegration of the basement membrane. In the alveoles hyperplasia and hypertrophy of type II (granular) pneumocytes often loosely connected with the basement membrane, were frequently demonstrated. Disintegration of the basement membrane accompanied by detachment of the pneumocytes occurred occasionally. In the interstitium lymphocytes, mast cells and plasma cells predominated. The size and shape of lymphocytes were variable. In addition, some lymphocytes with pseudopods were detected both in alveolar lumen and in the interstitium. Mast cells were found in close connection with plasma cells occasionally. Granulomas consisting of these cells and giant cells were usually present. Foreign material resembling hyphal fragments was found in the giant cells of two patients. The present series emphasizes the role of lymphocytes, macrophages, giant cells and mast cells, in the pathogenesis of EABA. The presence of numerous plasma cells in the lung parenchyma suggests the possibility of local antibody response caused by exposure to inhaled antigens.

Radiographic abnormalities among Finnish construction, shipyard and asbestos industry workers.

OBJECTIVES: The prevalence of asbestos-related radiographic abnormalities was surveyed among Finnish construction, shipyard, and asbestos industry workers. METHODS: The radiographic screening focused on active and retired workers who were under the age of 70 years and had been employed for at least 10 years in construction or for at least 1 year in shipyards or in the asbestos industry. In 1990-1992, 18,943 people participated in an X-ray examination of the lungs and an interview on work history and exposure. The criteria for a positive radiological finding were (i) small irregular lung opacities clearly consistent with interstitial pulmonary fibrosis (ILO 1/1 or higher), (ii) lung opacities indicating mild pulmonary fibrosis (ILO 1/0) with unilateral or bilateral pleural plaques, (iii) marked adhesions with or without thickening of the visceral pleura, or (iv) findings consistent with bilateral pleural plaques. RESULTS: Fulfilling the criteria were 4133 workers (22%) (22% from construction, 16% from shipyards, and 24% from the asbestos industry). The radiological findings included signs of pulmonary fibrosis (3%), changes in the visceral pleura (7%), bilateral plaques (17%), and unilateral plaques (10%). Occupational disease was diagnosed according to the Finnish insurance regulations for three-fourths of those referred for further examinations, 96% being abnormalities in the pleura and 4% being asbestosis. CONCLUSIONS: Exposure to asbestos dust has been common in ordinary construction work, and, consequently, radiographic abnormalities (mostly pleural) occur frequently among active and retired construction workers.

Detection of antigens in lung biopsies by immunoperoxidase staining in extrinsic allergic bronchiolo-alveolitis (EABA).

Open lung biopsy specimens of 14 patients with extrinsic allergic bronchiolo-alveolitis (EABA) were studied by immunoperoxidase staining with avidin-biotin-complex method using nonconjugated antisera to Micropolyspora faeni, Thermoactinomyces vulgaris, Aspergillus fumigatus, and Aspergillus umbrosus. Antigenic intracellular material was found in macrophages and giant cells of granulomas in the lung tissue of 8 patients. This finding supports the hypothesis which suggests that macrophages and T-lymphocytes contribute to the tissue injury in EABA.

Immunohistochemical identification of Aspergillus fumigatus in farmer's lung.

Fragments of fungi in a granuloma were demonstrated in lung biopsy specimens of two patients with farmer's lung by using an avidin-biotin-complex method with non-conjugated rabbit antiserum to Aspergillus fumigatus. Our findings suggest that the type IV or cell-mediated immunity at least partly explains the pathogenesis of farmer's lung.

Latex-induced allergic rhinitis in a laboratory nurse.

A case of occupational rhinitis in association with natural rubber latex hypersensitivity is presented. In the nasal provocation test for natural rubber latex glove powder the nurse experienced rhinorrhoea. A significant increase in the amount of nasal secretion and mucosal oedema could be detected. The patient also showed a positive skin prick test to natural rubber latex allergens, and an elevated natural rubber specific IgE level in her serum. This, to our knowledge, has not been previously reported in the literature.

A multi-faceted approach to risk assessment of laboratory animal allergens at two facilities.

BACKGROUND: Risk assessment of exposure to allergens is difficult because the relationship between exposure, sensitization, and symptoms has not been fully established. Laboratory animal allergens (LAA) are an important occupational health risk factor; 10-32% of workers exposed to these allergens develop allergic diseases. This article introduces a versatile approach to assessing the risks posed by LAA at two laboratory animal facilities. METHODS: The risk assessment approach that was used at the laboratory animal facilities included questionnaires for management and employees, a hazard identification visit and measurements in the workplaces, as well as the creation of a list of generally recommended procedures to reduce allergen exposure. RESULTS: The prevalence of work-related allergic symptoms was 17%. Suggested countermeasures at the sites included changes in ventilation and work practices, reduction of unnecessary exposure, recommendations for more comprehensive use of personal protective equipment, and wider communication about LAA risks. CONCLUSIONS: The approach managed to identify critical points and potential means for controlling LAA exposure.