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Background: Monocyte cell surface CD14 acts as the major lipopolysaccharide (LPS) binding structure, and as such is of interest in the etiology of LPS induced disease., Methods: The objective was to assess change in monocyte cell surface CD14 and CD4+ CD25+ lymphocytes in a group of cotton workers exposed to LPS over a working week, and to compare this to changes in office workers. Twenty-five cotton workers and nine office workers were studied. Monocyte CD14 fluorescence was measured by flow cytometry, on samples taken pre-shift on a Monday morning (baseline/pre-exposure), and subsequently after 6 and 72 hr. The majority of cotton workers were exposed to at least 1 EU/m(3) of endotoxin over a working shift, and some highly exposed (between 100 and 400 EU/m(3))., Results: After 6 hr of work in the mill, cotton workers developed a significant upregulation in CD14 in comparison to office workers (P = 0.016), whereas CD14 expression had returned to levels not significantly differing from the office workers at 72 hr after first work exposure (P = 0.426)., Conclusions: We propose that CD14 expression on monocytes may help to determine the mechanism of action of lipopolysaccharide in producing respiratory ill health, and may ultimately play a role in monitoring the health effect associated with LPS exposure in the workplace.

Objectives: To investigate a large population of cotton textile weavers for reported respiratory symptoms relative to occupational factors, smoking, and exposure to dust. Cotton processing is known to produce a respiratory disease known as byssinosis particularly in the early processes of cotton spinning. Relatively little is known about the respiratory health of the cotton weavers who produce cloth from spun cotton. By the time cotton is woven many of the original contaminants have been removed., Methods: 1295 operatives from a target population of 1428 were given an interviewer led respiratory questionnaire. The presence of upper and lower respiratory tract symptoms were sought and the work relatedness of these symptoms determined by a stem questionnaire design. Also occupational and demographic details were obtained and spirometry and personal dust sampling performed., Results: Byssinosis was present in only four people (0.3%). Chronic bronchitis had a moderate overall prevalence of about 6% and was related predominantly to smoking. There were several other work related respiratory symptoms (persistent cough 3.9%, chronic production of phlegm 3.6%, chest tightness 4.8%, wheezing 5.4%, and breathlessness 2.3%). All of these were predicted predominantly by smoking (either past or present), with no consistent independent effect of exposure to dust. Work related eye and nasal symptoms were more common (10.4% and 16.9% respectively)., Conclusion: Byssinosis is a rare respiratory symptom in cotton weaving. Other work related respiratory symptoms were reported but their presence was predominantly related to smoking with no consistent effects of exposure to dust.

Cotton dust sampling for monitoring worker exposure was traditionally performed by work area sampling. A change to an exposure limit based on personal sampling has recently been agreed. The choice of sampling head for personal monitoring exposure was hampered by the use of two different sampling heads in the major epidemiological studies of textile workers which had incorporated personal sampling techniques. The purpose of this study was to compare the results of exposure measurements using these two sampling heads. This study has examined the performance of the two sampling heads, by performing dual sampling on cotton operatives during normal working activities. Each operative included wore two samplers randomly allocated to left or right side. A minimum of 200 minutes of sampling was accepted and the relative concentrations calculated. The IOM total dust sampler produced repeatedly higher measurements than the Manchester head. The ratio overall was 1.33 (95% C.I. 1.20-1.49). The performance was similar across the ranges of dust exposure from low (< 1 mg/m3-ratio 1.28), medium (1-3 mg/m3-ratio 1.43) to high exposure (> 3 mg/m3-ratio 1.24). The two heads give reproducibly proportionate dust measurements with approximately 30% greater results obtained with the IOM total dust sampler. Either dust sampling head could be used for worker monitoring and the results adjusted accordingly for reference to the Maximum Exposure Limit.

Background: Exposure to cotton is known to produce a specific occupational disease known as byssinosis. A large population of textile workers was investigated to determine whether such exposure was also associated with chronic bronchitis once other possible aetiological factors had been accounted for., Methods: A total of 2991 workers were investigated for the presence of symptoms compatible with chronic bronchitis. An MRC adapted respiratory questionnaire and MRC definition of chronic bronchitis were used for diagnostic labelling. Current and lifetime exposure to dust was estimated by personal and work area sampling, and the use of records of retrospective dust levels previously measured over the preceding 10 years. Airborne endotoxin exposure was measured using a quantitative turbidometric assay. Lung function tests were performed to measure forced expiratory volume in one second (FEV1) and forced vital capacity (FVC). A control group of workers exposed to man-made fibre textiles was identified. The comparative prevalence of chronic bronchitis in the two populations was assessed, allowing for sex, age, smoking habit, and ethnic origin. Two case referent studies were also performed; cases of chronic bronchitis were separately matched with controls from the cotton and control populations to determine the effect of the symptomatic state on lung function., Results: After controlling for smoking (pack years), workers in a cotton environment were significantly more likely to suffer from chronic bronchitis and this was most marked in workers over 45 years of age (odds ratio 2.51 (CI 1.3 to 4.9); p < 0.01). Regression analysis of all possible influencing parameters showed that cumulative exposure to cotton dust was significantly associated with chronic bronchitis after the effects of age, sex, smoking, and ethnic group were accounted for (p < 0.0005). In the intra-cotton population case control study a diagnosis of chronic bronchitis was associated with a small decrement in lung function compared with controls: percentage predicted FEV1 in cases 81.4% (95% CI 78.3 to 84.6), controls 86.7% (84.9 to 88.5); FVC in cases 89.9% (95% CI 87.0 to 92.9), controls 94.6% (92.8 to 96.4). After controlling for cumulative past exposure and pack years of smoking the effect of the diagnostic state remained significant for both FEV1 (p < 0.01) and FVC (p < 0.05)., Conclusions: Chronic bronchitis is more prevalent in cotton workers than in those working with man-made fibre and exposure is additive to the effect of smoking. The diagnosis of chronic bronchitis is associated with a small but significant decrement in lung function.

Objectives: To document the prevalence of work related ocular (eyeWRI) and nasal (noseWRI) irritation in workers in spinning mills of cotton and synthetic textile fibres and to relate the prevalence of symptoms to atopy, byssinotic symptoms, work history, and measured dust concentrations in the personal breathing zone and work area., Methods: A cross sectional study of 1048 cotton workers and 404 synthetic fibre workers was performed. A respiratory questionnaire was given to 1452 workers (95% of the total available population). Atopy was judged by skin prick tests to three common allergens. Work area cotton dust sampling (WAdust) was carried out according to EH25 guidelines in nine of the 11 spinning mills included in the study. Personal breathing zone dust concentrations were assessed with the IOM sampler to derive total dust exposure (PTdust) and a concentration calculated after the removal of fly (Pless)., Results: 3.7% of all operatives complained of symptoms of byssinosis, 253 (17.5%) complained of eyeWRI and 165 (11%) of noseWRI. These symptoms did not relate to atopy or byssinosis, or correlate univariately with any measure of cotton dust exposure (noseWRI v WAdust r = 0.153, PTdust r = 0.118, eyeWRI v WAdust r = 0.029, PTdust r = 0.052). Both of these symptoms on logistic regression analysis were related to being of white origin (P < 0.001), female sex (P < 0.001), and younger age (P < 0.001). With regression analysis, there was a negative relation between dust concentration and prevalence of symptoms., Conclusion: Work related ocular and nasal irritation are the most common symptoms complained of by cotton textile workers. There was no relation between these symptoms and atopy, byssinosis, or dust concentration. It is likely that they relate to as yet unidentified agents unrelated to concentration of cotton dust.

In order to compare and contrast the sampling response to cotton dust of two forms of dust sampling 85 work areas were identified over a 2-year period for investigation in eight Lancashire spinning mills. Three hundred and five work area dust samples were undertaken and 252 personal dust samples were performed. Operatives who spent a minimum of 80% of their working shift in the area in which work area sampling was also performed were selected for personal sampling. Work area dust exposures have recently shown an upward trend, with highest concentrations occurring in the ring spinning room (median 1.15 mg m-3, range 0.82-2.06). Personal dust samples showed a reduction in dust exposures as cotton processing progressed, from a high in the opening room (median value of 6.24 mg m-3, range 1.0-41.5) to a minimum of 1.02 mg m-3 (range 0.30-0.93) in the winding room. The ratio of measured personal sampling dust exposure to work area sampling exposure was used to compare the relative performance of the two techniques. This ratio was highest in the early processes. There was a 7.8-fold difference in measurement between the two techniques in the opening processes, falling to 4.9 in carding and 4.2 in the other card-room processes. However in ring spinning the ratio was only 1.4, suggesting a degree of comparability in the methods at this stage of processing. The value rose to 2.5 for the last stage (winding). Respiratory disease is known to occur predominantly in the early stages of processing (opening and carding) where high dust concentrations are found using the personal technique. These data support the use of personal sampling for setting exposure limits to cotton dust in preference to the current recommended method using work area sampling techniques, which may significantly underestimate dust exposure in the high risk work areas and is outdated.