Håkan Löfstedt

Blood lead in Swedish police officers.

BACKGROUND Shooting with lead-containing ammunition in firing ranges is a well-known source of lead exposure in adults, and police officers may be at risk of lead intoxication. More stringent national lead regulations stimulated a survey of blood lead (PbB) in Swedish police officers with regular shooting habits. METHODS Police officers considered as the most active shooters on and/or off duty responded to a questionnaire about health, lifestyle, shooting habits, and potential lead exposure. Blood samples were collected and analyzed for PbB and a multivariate regression analysis was performed. RESULTS The mean PbB in male officers (n = 75) was 0.24 mumol/L (5.0 micrograms/dL); range 0.05-0.88 mumol/L (1.0-18.2 micrograms/dL), and in female officers (n = 3) it was even lower (0.18 mumol/L; 3.7 micrograms/dL). For both sexes combined, a positive correlation (r = 0.55; P < 0.001) of PbB with the number of bullets annually fired both on and off duty was observed, and this finding remained in a multiple regression analysis including age, smoking habits, and latency from last shooting exercise. DISCUSSION In conclusion, occupational and recreational lead exposure from firing ranges still seems to be a source of lead exposure in Swedish police officers, but it no longer appears to be a health risk. Lead-free communication and well-ventilated indoor firing ranges may have been decisive for this encouraging finding.

Nasal and ocular effects in foundry workers using the hot box method.

Objective: To investigate the prevalence of nasal and ocular symptoms and nasal signs in foundry workers exposed to monoisocyanates using the Hot Box method. Methods: Forty-three foundry workers and 69 referents completed questionnaires and were examined by a rhinologist. Exposure to isocyanic acid, methyl isocyanate, formaldehyde, and total dust was measured. Results: Nasal symptoms and signs were associated with exposure, and dose–response relationships between nasal symptoms and exposure to isocyanic acid, methyl isocyanate, and formaldehyde were observed. Dry nasal mucosa was more prevalent in exposed workers than in referents. These findings were not substantially affected by the exclusion of asthmatic and allergic individuals, smokers, or females. Conclusions: An increased prevalence of nasal symptoms and signs was observed among exposed workers, suggesting an association with the foundry environment involving monoisocyanates and other airway irritants, such as formaldehyde and dust.

Respiratory symptoms and lung function in foundry workers exposed to low molecular weight isocyanates

BACKGROUND This study investigated the prevalence of ocular and respiratory symptoms and lung function in foundry workers exposed to isocyanic acid (ICA) and methyl isocyanate (MIC). METHODS Foundry workers (n = 64) using the Hot Box binder technique and referents (n = 134) completed two questionnaires and a spirometry before and after a day shift. Findings were analyzed relating to exposure measurements of ICA, MIC, and formaldehyde. RESULTS Exposed workers reported more frequently ocular irritation and coughing. Pre-shift lung function was lower than predicted in both groups of workers, and was not associated with exposure duration. Decrease in lung function over shift was more pronounced in exposed workers, but this was not associated with quantitative measures of the exposures. CONCLUSIONS An increased prevalence of ocular and respiratory symptoms, as well as a small decrease in lung function over shift, was observed among exposed workers. No associations with exposure to monoisocyanates and formaldehyde were seen, thus suggesting that other irritants in the foundry environment might be the cause. The effects seemed to be small and not clinically relevant on an individual level. Further studies using a follow-up design may be warranted.

Respiratory symptoms and lung function in relation to wood dust and monoterpene exposure in the wood pellet industry

Abstract Introduction: Wood pellets are used as a source of renewable energy for heating purposes. Common exposures are wood dust and monoterpenes, which are known to be hazardous for the airways. The purpose of this study was to study the effect of occupational exposure on respiratory health in wood pellet workers. Materials and methods: Thirty-nine men working with wood pellet production at six plants were investigated with a questionnaire, medical examination, allergy screening, spirometry, and nasal peak expiratory flow (nasal PEF). Exposure to wood dust and monoterpenes was measured. Results: The wood pellet workers reported a higher frequency of nasal symptoms, dry cough, and asthma medication compared to controls from the general population. There were no differences in nasal PEF between work and leisure time. A lower lung function than expected (vital capacity [VC], 95%; forced vital capacity in 1 second [FEV1], 96% of predicted) was noted, but no changes were noted during shifts. There was no correlation between lung function and years working in pellet production. Personal measurements of wood dust at work showed high concentrations (0.16–19 mg/m3), and exposure peaks when performing certain work tasks. Levels of monoterpenes were low (0.64–28 mg/m3). There was no association between exposure and acute lung function effects. Conclusions: In this study of wood pellet workers, high levels of wood dust were observed, and that may have influenced the airways negatively as the study group reported upper airway symptoms and dry cough more frequently than expected. The wood pellet workers had both a lower VC and FEV1 than expected. No cross-shift changes were found.

Occupational Exposure to Trichloramine and Trihalomethanes in Swedish Indoor Swimming Pools: Evaluation of Personal and Stationary Monitoring

Introduction: Chlorination is a method commonly used to keep indoor swimming pool water free from pathogens. However, chlorination of swimming pools produces several potentially hazardous by-products as the chlorine reacts with nitrogen containing organic matter. Up till now, exposure assessments in indoor swimming pools have relied on stationary measurements at the poolside, used as a proxy for personal exposure. However, measurements at fixed locations are known to differ from personal exposure. Methods: Eight public swimming pool facilities in four Swedish cities were included in this survey. Personal and stationary sampling was performed during day or evening shift. Samplers were placed at different fixed positions around the pool facilities, at ~1.5 m above the floor level and 0–1 m from the poolside. In total, 52 personal and 110 stationary samples of trichloramine and 51 personal and 109 stationary samples of trihalomethanes, were collected. Results: The average concentration of trichloramine for personal sampling was 71 µg m−3, ranging from 1 to 240 µg m−3 and for stationary samples 179 µg m−3, ranging from 1 to 640 µg m−3. The air concentrations of chloroform were well below the occupational exposure limit (OEL). For the linear regression analysis and prediction of personal exposure to trichloramine from stationary sampling, only data from personal that spent >50% of their workday in the pool area were included. The linear regression analysis showed a correlation coefficient (r 2) of 0.693 and a significant regression coefficient β of 0.621; (95% CI = 0.329–0.912, P = 0.001). Conclusion: The trichloramine exposure levels determined in this study were well below the recommended air concentration level of 500 µg m−3; a WHO reference value based on stationary sampling. Our regression data suggest a relation between personal exposure and area sampling of 1:2, implying an OEL of 250 µg m−3 based on personal sampling.

Respiratory symptoms and lung function in foundry workers using the hot box method: a 4-year follow-up.

Objective: To perform follow-up of lung function and respiratory and ocular symptoms in foundry workers exposed to monoisocyanates using the Hot Box method. Methods: Four years after an initial assessment, 25 foundry workers and 55 referents completed a questionnaire and were assessed by spirometry pre- and postshift. Exposure to isocyanic acid, methyl isocyanate, and formaldehyde was measured. Results: Exposure levels were reduced by 50% at follow-up. A high prevalence of nasal and ocular symptoms remained in both groups, but lower airway symptoms had decreased. Lung function preshift was lower for the exposed group, but lung function over shift was unaffected. Conclusions: The high prevalence of nasal symptoms and the small reduction of forced expiratory volume in 1 second preshift in exposed foundry workers at follow-up may indicate a prolonged influence of previous exposure in the working environment despite reduced exposure levels at follow-up.

715 Occupational exposure to trichloramine and trihalomethanes adverse health effects in rehabilitation swimming pools

Introduction Studies have shown that employees and visitors at indoor swimming pool facilities are experiencing symptoms in the nose and throat, eye irritation and, in some cases, asthma. Due to chlorination, byproduct such as trichloramine and trihalomethanes can be present in indoor swimming pool air. This exposure has not been described in rehabilitation swimming pools that normally consists of smaller facilities and use warmer water compared to ordinary swimming pools. Methods The occupational exposure of trichloramine and trihalomethanes in air has been studied at ten Swedish indoor swimming pool facilities. The study has also included the prevalence of ocular symptoms and symptoms and effects on the upper and lower respiratory tract. Nitrogen oxide (NO) in exhaled air has been investigated as a measure of early respiratory tract inflammation. Results The average trichloramine concentration for personal measurements (n=17) was 23 µg/m3, varying between 1 and 76 µg/m3. Corresponding stationary measurements (n=27) performed at the pool side showed an average concentration of 30 µg/m3, varying between 1 and 140 µg/m3. A WHO reference value for trichloramine, based on stationary measurements, is set to 500 µg/m3. The levels of trihalomethanes for both personal (n=20) and stationary (n=35) measurements were less than 1% of the Swedish OEL for chloroform. Measurements of NO in exhaled air showed a change during shift when exposed (n=23) and controls (n=50) were compared. Discussion Both personal and stationary measurements showed low levels of trichloramine and trihalomethanes. When comparing exposed and controls during shift, a difference of NO in exhaled air was noted.

Occupational exposure to trichloramine and trihalomethanes: adverse health effects among personnel in habilitation and rehabilitation swimming pools

Abstract Personnel in swimming pool facilities typically experience ocular, nasal, and respiratory symptoms due to water chlorination and consequent exposure to disinfection by-products in the air. The aim of the study was to investigate exposure to trichloramine and trihalomethanes (chloroform, bromodichloromethane, dibromochloromethane, and bromoform) from the perspective of adverse health effects on the personnel at Swedish habilitation and rehabilitation swimming pools. The study included 10 habilitation and rehabilitation swimming pool facilities in nine Swedish cities. The study population comprised 24 exposed swimming pool workers and 50 unexposed office workers. Personal and stationary measurements of trichloramine and trihalomethanes in air were performed at all the facilities. Questionnaires were distributed to exposed workers and referents. Spirometry, fraction of exhaled nitric oxide (FENO), and peak expiratory flow (PEF) were measured. Personal and stationary measurements yielded trichloramine levels of 1–76 µg/m3 (average: 19 µg/m3) and 1–140 µg/m3 (average: 23 µg/m3), respectively. A slightly higher, but not significant, prevalence of reported eye- and throat-related symptoms occurred among the exposed workers than among the referents. A significantly increased risk of at least one ocular symptom was attributed to trichloramine exposure above the median (20 µg/m3). Lung function (FVC and FEV1) was in the normal range according to the Swedish reference materials, and no significant change in lung function before and after shift could be established between the groups. Average FENO values were in the normal range in both groups, but the difference in the values between the exposed workers and referents showed a significant increase after shift. Hourly registered PEF values during the day of the investigation did not show any unusual individual variability. In conclusion, the increased risk of developing at least one ocular symptom at personal trichloramine concentrations over 20 µg/m3 combined with an increase in the difference in FENO during the work shift of the exposed workers should not be neglected as an increased risk of respiratory inflammation in the habilitation and rehabilitation swimming pool environment.

Respiratory and Ocular Symptoms Among Employees at Swedish Indoor Swimming Pools

Background: This study investigated trichloramine exposure and prevalence of respiratory and ocular symptoms among Swedish indoor swimming pool workers. Methods: Questionnaires were distributed to pool workers and referents. Lung function and fraction of exhaled nitric oxide (FeNO) were measured before and after work. Exposure to trichloramine and trihalomethanes was measured over work shifts. Results: The mean personal trichloramine exposure was 36 &mgr;g/m3. Significantly more exposed workers reported ocular and nasal symptoms. There were significant differences between groups in FeNO change following work, with exposed showing increased FeNO, which grew when analyses included only nonsmokers. Conclusions: The findings indicate that indoor swimming pool environments may have irritating effects on mucous membranes. FeNO data also indicate an inflammatory effect on central airways, but the clinical relevance is unclear. Low trichloramine levels found in this study were not associated with health effects.