Birgitta Kolmodin-Hedman

Exposure to Formaldehyde: Effects on Pulmonary Function

Forty-seven subjects exposed to formaldehyde (mean air concentration 0.45 mg/m3) and 20 unexposed subjects, all of whom were employed at a carpentry shop, were studied with regard to symptoms and pulmonary function. Symptoms involving eyes and throat as well as chest oppression were significantly more common in the exposed subjects than in the unexposed controls. Spirometry and single breath nitrogen washout were normal Monday morning before exposure to formaldehyde. A reduction in forced expiratory volume in 1 sec by an average of 0.2 L (P = .002), percent forced expiratory volume by 2% (P = .04), maximum midexpiratory flow by 0.3 L/sec (P = .04) and an increase in closing volume in percentage of vital capacity by 3.4% (P - .002) were seen after a day of work and exposure to formaldehyde, suggesting bronchoconstriction. Smokers and nonsmokers displayed similar changes in spirometry and nitrogen washout.

Occupational handling of cytostatic drugs

The bacterial fluctuation test and measurement of the frequency of sister chromatid exchanges were used for evaluation of the exposure of different groups of hospital personnel to cytostatic drugs.Increased mutagenic activity in the urine was detected only in personnel working with inadequate safety precautions, e.g., lack of a ventilated safety cabin for preparation of parenteral solutions. Although such a safety cabin was used within the hospital pharmacy, increased mutagenic activity was detected in the urine of prescriptionists preparing parenteral cytostatic drugs. After a change of glove material and improvement of ventilation in the safety cabin, no work-related increase in urinary mutagenic activity was seen. None of the different groups tested, showed any increase in the frequency of sister chromatid exchanges.It is therefore concluded that handling of cytostatic drugs according to the issued safety recommendations including working in a well ventilated safety cabin, will not result in any enhancement of mutagenic activity in the urine related to work.

Occupational exposure to some synthetic pyrethroids (Permethrin and Fenvalerate)

In a two-step study an exposure control method for occupational handling of permethrin was developed.Air sampling on a filter can be used in cases of exposure to permethrin in powder form. The detection limit is 0.001 mg/m3.If biological sampling is used, the acid metabolite moiety in the urine must be monitored. However, the uptake after exposure to permethrin in forestry was too low, and no urine concentration could be found. The detection limit is 0.1 μg/ml. Six persons in a plant nursery and six planters were studied in this way. Interviews were conducted with 139 planters.Irritative symptoms form the skin and upper respiratory tract were reported in 73% for fenvalerate, 63% for permethrin (trans/cis 75/25) and 33% for permethrin (trans/cis 60/40).

Studies on phenoxy acid herbicides

In the presented study we wanted to establish a biological monitoring of exposure in farmers occupationally exposed to phenoxy acid herbicides (MCPA, dichlorprop mecoprop, and 2,4-D). The individual airborn concentrations were measured as well as the urinary concentration before, during and after exposure.Twentyfour male farmers and nine professional spray-men were studied and compared.The air concentrations were low, < 0.001–0.1 μg/m3. Urinary concentrations were variable < 0.05–12 μg/ml (MCPA).Uptake by dermal absorption seems to be dominant, swallowing of sprayed droplets and inhalation are possible routes of entrance. Urinary concentrations of phenoxy acid herbicides (MCPA, dichlorprop, and mecoprop) measured at the end of an exposure period or preferably the following morning could be used to give a reflection of recent exposure.

Studies on phenoxy acid herbicides. II. Oral and dermal uptake and elimination in urine of MCPA in humans.

Five healthy volunteers were given 15 μg MCPA per kg body weight. The highest concentration in plasma, 0.15 μg/ml, was found after 1 h. In urine the excretion during the first 6 h was 0.46 μg/min and 40% of given dose was excreted during the first 24 h.About 1 g of MCPA emulsion was applied on the skin of the thigh and was washed away after 2 h. Plasma level slowly increased with maximum, 0.12 μg/ml, after 24 h. In urine a slow excretion continued for up to 5 days later with maximum 24–48 h after application.In agricultural field exposure urinary MCPA should be estimated immediately after stop of exposure as well as 24 h after exposure.Levels under 0.5 μg/ml of MCPA in urine might be used as a practical biological level for good work practice. In spot samples the concentration of urine must be considered.

Health problems among operators of plastic welding machines and exposure to radiofrequency electromagnetic fields

SummaryTo study possible medical effects of high radiofrequency radiation (RF), 113 Swedish men and women were studied by means of a structured interview and rating of subjective symptoms. A test session was included in order to examine coordination and muscular function of the hands. A neurological test concerning two-point discrimination (2-PD) was also done. As referents, 23 women, sewing machine operators and assembly workers, were chosen, interviewed and likewise tested. Exposure measurements were taken of the RF fields around the welding machines. The present Swedish ceiling value of 250 W/m2 for the equivalent power density was exceeded in more than 50% of the machines. The highest leakage fields, both for electric and magnetic fields, were found near machines used in factories for ready-made clothing, which gave a high exposure to the hands. Irritative eye symptoms were reported by 23% of the men and 40% of the women. A group of 27 persons was selected for a clinical eye examination and checked by photographs, and nine persons had modest conjunctivitis. A high prevalence of numbness in hands, especially among women, was found. A significantly impaired 2-PD was found in the exposed women as compared to the referent group. The pregnancy outcome for 305 female plastic welders during 1974–1984 did not show any significant differences with the Swedish average concerning malformation or prenatal mortality.

Is the short term limit value for sulphur dioxide exposure safe? Effects of controlled chamber exposure investigated with bronchoalveolar lavage.

Bronchoalveolar lavage (BAL) which has not previously been used in investigating the effect of sulphur dioxide (SO2) on the human lung was performed on 12 subjects before and after controlled chamber exposure with SO2 for 20 minutes. BAL fluid 24 hours after exposure with 10 mg SO2/m3 (4 ppm, 10 subjects) showed increased alveolar macrophage activity as judged by an increase in lysozyme positive macrophages. Twenty four hours after 20 mg/m3 (4 subjects) a further increase was seen, which was accompanied by an increase in total numbers of macrophages and lymphocytes. Seventy two hours after exposure (4 subjects) cell numbers had virtually returned to pre-exposure levels. These previously uninvestigated reactions indicate potentially noxious effects of SO2 in the lungs at exposure levels that are regarded as relatively safe.

Mould exposure in museum personnel.

SummaryIn the basement archives of a local arts and crafts museum where the books and bookkeeping registers were handled, a woman on the museum staff had had ten attacks of fever, chill, nausea and cough during one year. The symptoms appeared at the end of the working day and disappeared after one to three days at home. No symptoms could be detected during the summer holidays. The books stored in the basement archives had earlier been stored in a small house with a leaky roof, which had led to the growth of mould on the books. When the books were handled at the museum, they were still covered with mould. The exposure measurements showed 106 CFU/m3 and a total of 108 microorganisms/m3.

Exposure to peat dust: acute effects on lung function and content of bronchoalveolar lavage fluid.

Mechanised production of peat for fuel consumption is associated with high concentrations of organic dust, which is inhaled by the peat workers. In the present study 17 workers at two peat bogs in northern Sweden were examined. Personal sampling of total dust and the respirable fraction was performed during several workshifts. Dynamic spirometry was carried out before and at the end of shifts. Bronchoscopy with bronchoalveolar lavage (BAL) was performed in six subjects at the end of the working season and the results were compared with unexposed reference subjects. Peat workers using modern machines with ventilated cabins containing air filters were found to be exposed to low concentrations of peat dust. The recorded dust concentrations were below the threshold limit value for organic dust (5 mg/m3 air) in all but one worker. The respirable fraction of peat dust recorded in the breathing zone of the workers correlated significantly with a decrease in forced expiratory volume in one second (FEV1). The effect on lung function in non-asthmatic peat workers was, however, small. The concentration of lysozyme positive alveolar macrophages in BAL fluid was significantly lower in the peat workers compared with reference subjects. An inverse correlation was found between the mentioned cells and exposure to the respirable fraction of the peat dust. Furthermore, one particularly dust exposed worker had pronounced increases in alveolar macrophages, fibronectin concentration, and mast cells in BAL fluid.