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Objectives: To assess the distribution of personal exposures to nitrogen dioxide (NO2) in school children, and to investigate factors that might influence personal exposure.Methods: NO2 exposures were assessed by use of passive diffusion tubes for 46 children aged 9-11 years, selected from two Southampton schools. The tubes were worn for seven days, and parallel measurements were made with static samplers in the child's kitchen, living room, classroom, and playground. Information about potential exposures was collected by questionnaire.Results: Personal exposures to NO2, averaged over seven days, ranged from 11 to 257 micrograms/m3 (6 to 137 ppb) with a geometric mean of 36 micrograms/m3 (19 ppb). Exposures correlated with concentrations of NO2 recorded in the home, but the relation was far from exact. Factors associated with increased personal exposure included the use of gas appliances in the home, living with one or more smokers, and travel to school by means other than a car. However, together these variables only explained a small part of the variation in personal exposures.Conclusions: These findings reinforce the need for personal monitoring of exposure in studies investigating potential health effects of NO2 in children. [ABSTRACT FROM AUTHOR]

Occupational exposure to metal fume promotes a reversible increase in the risk of pneumonia, but by mechanisms which are unclear. To investigate, the current authors measured various markers of host defence function in welders and nonwelders. Induced sputum and venous blood samples were collected from 27 welders with regular long-term exposure to ferrous metal fume and 31 unexposed matched controls. In sputum, the present authors measured cell counts, the soluble and cellular iron concentration, and levels of interleukin-8, tumour necrosis factor-alpha, myeloperoxidase, matrix metalloproteinase-9, immunoglobulin (Ig)A, alpha(2)-macroglobulin and unsaturated iron-binding capacity. Blood samples were assayed for evidence of neutrophil activation and pneumococcal IgG antibodies. Welders had significantly higher iron levels and a substantially lower unsaturated iron-binding capacity in their sputum, but, despite a high iron challenge, there was a noteworthy absence of an inflammatory response. Only blood counts of eosinophils and basophils were significantly related to the extent of welding. Weak nonsignificant trends were observed for several other measures, consistent with low-grade priming of neutrophils. In conclusion, these data suggest that chronic exposure to metal fume blunts responsiveness to inhaled particulate matter. However, the mechanism behind the lack of detectable local inflammatory response requires further investigation.

Regional musculoskeletal disorders are a major cause of morbidity both in the community and in the workplace. They comprise a heterogeneous group of conditions that are, for the most part, poorly characterized. Consequently, agreed diagnostic criteria have not existed for many of these disorders, and epidemiological investigations have used varied or ill-defined approaches to case definition. This chapter describes our current understanding of the epidemiology of regional pain disorders and details the strengths and weaknesses of the available data. Pain syndromes can be divided anatomically into those which cause generalized pain, such as fibromyalgia syndrome and myofascial pain syndromes, and those which are confined to one regional anatomical area. The latter group comprise those of the neck, shoulder, elbow, wrist/hand, hip, knee and ankle/foot. Current information is considered on the known risk factors for disorders at these sites, in addition to their impact upon both the individual and society.

Background: Although beta2-adrenoceptor agonists are widely used in the treatment of asthma, a number of studies have suggested that their long-term use may exacerbate the condition. One possible mechanism for this stems from the in vitro observation that beta2-agonists increase IgE synthesis by human blood mononuclear cells., Objective: We sought to examine the effect of regular beta2-agonist therapy on IgE production in vivo in human volunteers., Methods: Placebo or salbutamol (8 mg BD) tablets were given in a double-blind, randomized fashion to 25 volunteers allergic to grass pollen throughout a period encompassing the UK grass pollen season (April through September). Levels of serum IgE were measured monthly, and nasal IgE was measured at the height and end of the season. Efficacy was assessed through monthly recordings of symptoms of blocked nose (vascular) and other symptoms of rhinitis (nonvascular)., Results: For the whole group the geometric mean of serum IgE levels rose from a baseline of 58.7 IU/mL (range, 0 to 1027 IU/mL) to 140 IU/mL (range, 12 to 878 IU/mL) at the height of the pollen season (P =.0001). There was no significant difference between the magnitude of the rise in IgE between the groups with a ratio of increase for salbutamol/placebo of 1.17 (confidence interval = 0.78 to 1.75). There was no change in nasal IgE levels. Total and nonvascular symptom scores were reduced by salbutamol, reaching statistical significance at the height of the pollen season (P <.05)., Conclusion: An oral dose of the beta2-agonist salbutamol, sufficient to maintain therapeutic levels and provide clinical benefit, does not accentuate the seasonal increase of IgE in human atopic volunteers.