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1.  Some Pharmacological Actions of Cotton Dust and Other Vegetable Dusts 
Aqueous extracts of cotton and other vegetable dusts cause contraction of the isolated ileum and tracheal muscle of the guinea-pig, and of isolated human bronchial muscle. The levels of this contractor activity place the dusts of cotton, flax, and jute in the order of the probable incidence of byssinosis occurring in the mills spinning these fibres.
Extracts of cotton dust possess a histamine-liberating activity and contain a permeability-increasing component. These actions are of plant origin and are found in the pericarp and bracts of the cotton boll. Histamine and 5-hydroxytryptamine have also been found in some cotton dust samples. The formation of histamine by bacterial action in cotton dust does not take place under conditions found in cotton mills. The smooth muscle contractor substance is organic in nature, relatively heat-stable, and dialysable. The relevance of these results to the symptoms of byssinosis is discussed.
PMCID: PMC1038128  PMID: 14479451
2.  A Clinical and Environmental Study of Byssinosis in the Lancashire Cotton Industry 
The prevalence of byssinosis was measured in a population of 189 male and 780 female workers employed in three coarse and two fine cotton mills. Ninety-eight per cent. of the male and 96% of the female population were seen.
The workers were graded by their histories as follows:
Grade 0—No symptoms of chest tightness or breathlessness on Mondays
Grade ½—Occasional chest tightness on Mondays, or mild symptoms such as irritation of the respiratory tract on Mondays
Grade 1—Chest tightness and/or breathlessness on Mondays only
Grade 2—Chest tightness and/or breathlessness on Mondays and other days
The dust concentrations to which the workers were exposed were measured with a dust-sampling instrument based on the hexhlet. Altogether 505 working places were sampled. In the card-rooms of the coarse mills 63% of the men and 48% of the women had symptoms of byssinosis. In the card-rooms of the fine mills the corresponding prevalences were 7% for the men, and 6% for the women. Prevalences were low in the spinning-rooms in the coarse mills. The mean dust concentrations in the different rooms ranged from 90 mg./100 m.3 in one section of the card-room in a fine mill, to 440 mg./100 m.3 in one of the card-rooms of the coarse spinning mills. The prevalence of byssinosis in the different rooms was closely related to the overall dustiness (r = 0·93). For the three main constituents of the dust, namely, cellulose, protein, and ash, the prevalence of byssinosis correlated most highly with protein, particularly with the protein in the medium-sized dust particles, i.e., approximately 7 microns to 2 mm.
The symptoms of byssinosis may be caused by something in the plant débris which affects the respiratory tract above the level of the terminal bronchioles. This is the site where the medium-sized dust deposits. The possible importance of the fine dust is discussed.
For routine measurements in industry, it is necessary to have a method of assessing dustiness in which the sampling equipment is simple and assessment rapid. As total dust concentration is relatively easy to measure, and correlates closely with the prevalence of byssinosis, permissible levels of dustiness have been expressed in terms of total dust. On comparing the prevalence of byssinosis among workers with short and long exposures and low and high concentrations (Table 11), it appears that a mill with a concentration of 100 mg./100 m.3 or less would be reasonably safe, but in dusty card-rooms it seems that such levels are not possible to achieve at present. As it is necessary to adopt a realistic target that can be achieved, it is suggested that dust concentrations in cotton mills should be less than 250 mg./100 m.3 and that periodic medical examinations should be adopted to protect susceptible workers who can be advised to leave their dusty environment before they are permanently disabled.
PMCID: PMC1039177  PMID: 14437722
3.  The Pharmacological Activity of Extracts of Cotton Dust 
Aqueous extracts prepared from dust collected in the card-rooms of several cotton mills have been prepared and found to contain activity which contracts the smooth muscle of guinea-pig ileum, guinea-pig trachea, rat stomach strip, and rat duodenum. The extracts contained an unknown contractor substance which was dialysable, resistant to boiling for one hour, and not destroyed by the action of proteolytic enzymes. They also contained a small amount of 5-hydroxytryptamine. One of the dust samples also contained histamine, but it could not be detected in the other samples, one of which was known to possess bronchoconstrictor properties in man. The particulate material, even after repeated washing, was found to have some stimulant action on guinea-pig ileum.
There was no evidence for the release of histamine by the extracts in either cats or guinea-pigs, although a very small amount was released in rats. Jute dust is much less active than cotton dust, and the activity differs qualitatively. Cotton dust extracts were found to have pyrogenic activity but it is unlikely that pyrogens were responsible for the smooth-muscle contractor properties. Experiments with whole animals suggest that although smooth-muscle contracting substances were present in the extracts, it is possible that the symptoms of byssinosis are caused by the release of some other active bronchoconstrictor substance in the tissues. The mechanism of the release is not known; it may be caused by a soluble principle in the extract or due to the presence of particulate matter in the dust.
PMCID: PMC1038127  PMID: 13883719
4.  Preprocessing cotton to prevent byssinosis 
Merchant, J. A., Lumsden, J. C., Kilburn, K. H., Germino, V. H., Hamilton, J. D., Lynn, W. S., Byrd, H., and Baucom, D. (1973).British Journal of Industrial Medicine,30, 237-247. Preprocessing cotton to prevent byssinosis. A fundamental approach of cleaning or deactivating cotton prior to manufacturing has long been advocated to prevent byssinosis, but no trial had been conducted to test the feasibility of such an approach. In the study described, it was possible to be directed by both biological observations and the results of manufacturing trials.
An exposure chamber was built in a cotton textile mill which had been previously studied as part of a large cross-sectional survey. The chamber was provided with an independent air conditioning system and a carding machine which served as a dust generator. Sixteen subjects, who had shown reductions in expiratory flow rate with exposure to cotton dust, were chosen to form a panel for exposure to raw cottons and cottons which had been preprocessed by heating, washing, and steaming. Indicators of effects were symptoms of chest tightness and/or dyspnoea, change in FEV1·0, and fine dust levels over 6 hours of exposure.
Exposure of the panel to no cotton dust resulted in no change in FEV1·0 and served as the control for subsequent trials. Exposure to strict middling cotton resulted in a byssinosis symptom prevalence of 22%, a significant decrement in FEV1·0 of 2·9%, and a fine dust level of 0·26 mg/m3. Exposure to strict low middling cotton resulted in a byssinosis symptom prevalence of 79%, a decrement in FEV1·0 of 8·5%, and a fine dust level of 0·89 mg/m3. Oven heating strict low middling cotton resulted in a byssinosis symptom prevalence of 56% and a relatively greater drop in FEV1·0 of 8·3% for 0·48 mg/m3 of fine dust. Washing the strict low grade cotton eliminated detectable biological effects with a symptom prevalence of 8%, an increase of 1·4% in FEV1·, and a dust level of 0·16 mg/m3, but the cotton proved to be difficult to process. As an alternative method, strict low middling cotton was steamed initially in large dyeing vats, on a conveyor, in an autoclave, and in a modified yarn dyeing apparatus or `pipe' steamer. Of these methods, autoclaving cotton was the most successful, reducing symptom prevalence to 8%, the drop in FEV1·0 to 0·4%, and the dust level to 0·23 mg/m3. Development of a high capacity cotton steamer based on the small `pipe' steaming model resulted in a symptom prevalence of 8%, a decrement in FEV1·0 of 0·8%, and a mean dust level of 0·27 mg/m3. Regressions calculated from raw and high capacity steaming trials indicate that at low dust levels steamed cotton dust was roughly one half as biologically active as raw cotton dust.
PMCID: PMC1009518  PMID: 4723787
5.  A comparative study of respiratory function in female non-smoking cotton and jute workers 
Valić, F., and Žuškin, E. (1971).Brit. J. industr. Med.,28, 364-368. A comparative study of respiratory function in female non-smoking cotton and jute workers. To compare the effect of cotton and jute dust, respiratory symptoms were studied and respiratory function measured in 60 cotton and 91 jute non-smoking female workers of similar age distribution, similar length of exposure to dust, and exposed to similar respirable airborne dust concentrations. Cotton workers had a significantly higher prevalence of byssinosis, of persistent cough, and of dyspnoea (P < 0·01) than jute workers. Among cotton workers 28·3% were found to have characteristic symptoms of byssinosis, whereas none was found among jute workers.
Exposure to cotton but also to jute dust caused significant reductions of FEV1·0, FVC, and PEF (P < 0·01) over the first working shift in the week. Functional grading of jute and cotton dust effects has shown that about 30% of cotton workers had functional grades F1 and F2, while only 13% of jute workers were found in the same grades (F1). It is concluded that cotton dust may be considered more active than jute though the latter cannot be considered inactive.
PMCID: PMC1009330  PMID: 5124836
6.  Effects of different vegetable dust exposures1 
Valić, F., and Žuškin, E. (1972).Brit. J. industr. Med.,29, 293-297. Effects of different vegetable dust exposures. In order to establish the rank of biological activity of vegetable dusts, five groups of non-smoking female workers exposed to similar concentrations of hemp, flax, cotton, sisal, and jute airborne dust, respectively, were compared as to the prevalence of byssinosis, chronic respiratory symptoms, and one-second expiratory volume changes over the Monday shift. The groups were selected in such a way as to differ in the distribution of age and length of exposure to the respective dust as little as possible.
The prevalence of byssinosis in hemp and flax workers was approximately equal (44% and 43% respectively), in cotton workers it was considerably lower (27%), while no byssinosis was caused by either sisal or jute dust. The highest prevalence of other chronic respiratory symptoms was recorded in hemp workers (39%), followed by flax (36%) and cotton workers (27%), while in sisal (13%) and jute workers (13%) it was the lowest.
Significant mean FEV1·0 reductions over the shift were recorded in all the groups of textile workers with the largest reductions in hemp workers (19%) followed by flax (11%), cotton (8%), sisal (7%), and jute workers (5%). The application of orciprenaline before the shift diminished the mean acute FEV1·0 falls over the work shift in all the groups studied.
PMCID: PMC1009427  PMID: 5044600
7.  Byssinosis: The Acute Effect on Ventilatory Capacity of Dusts in Cotton Ginneries, Cotton, Sisal, and Jute Mills 
Studies of ventilatory capacity change in small groups of employees during a shift in a cotton mill and in three cotton ginneries in Uganda, a sisal factory in Kenya, and a jute mill in England, have demonstrated that an effect is produced by the dust in the cotton mill and in a very dusty ginnery but not in two other less dusty ginneries. No significant effect was detected in the sisal factory or in the jute mill despite much higher dust concentrations than in the cotton mill.
The dust sampling instruments gave the weight in three sizes: Coarse (>2 mm.), medium (7μ to 2 mm.), and fine (<7μ). The samples were analysed for protein, mineral (ash), and cellulose (by difference). The fine and medium sisal and jute dusts contain less protein than cotton dusts. The physiological changes observed in the employees in the cotton mill indicate the need for general dust measurement and control, even when new carding machinery is installed in a new mill.
PMCID: PMC1038126  PMID: 13898707
The prevalence of byssinosis and chronic respiratory symptoms was studied in 117 workers in four Swedish cotton mills. Changes of forced expiratory volume in 0·75 sec. (F.E.V.0·75) during a Monday and a Wednesday were assessed in 64 male workers in four cardrooms in these mills. Dust sampling was performed with weighed millipore filters.
Prevalences of byssinosis as judged from the workers' histories were 68%, 55%, 44%, and 25% in the four mills; the lowest prevalence of 25% was found in a mill spinning both high grade cotton yarn and rayon. Among 67 workers in the mills having a byssinosis prevalence of 68% and 55%, 60% were non-smokers, 70% had chronic cough, and 27% had chronic dyspnoea. The F.E.V.0·75 decreased on Monday in workers who gave a history of Monday dyspnoea, and to a lesser degree, but still significantly, in those who did not.
In spite of marked differences in fine dust (i.e., dust smaller than 2 mm. diameter) concentrations in the four cardrooms, no significant relations between dust content, byssinosis prevalence, and F.E.V.0·75 changes on Monday could be demonstrated.
The prevention and treatment of byssinosis is discussed. Workers at risk should receive a periodical medical examination including at least a spirographical pulmonary function test at intervals of one year or less.
PMCID: PMC1008256  PMID: 14278797
9.  Byssinosis among Winders in the Cotton Industry 
In a mill spinning coarse cotton the prevalence of byssinosis and other respiratory symptoms, and the F.E.V.1·0, were measured in a group of 29 men and 117 women employed in the winding room. All the men and 95% of the women at risk were included.
Dust concentrations, measured with a modified Hexhlet at various work points in the winding room, ranged from 1·65 to 6·05 mg./m.3 total dust. These concentrations are higher than 1·0 mg./m.3, which is the threshold limit value for cotton dust recommended by the American Conference of Governmental Industrial Hygienists. The mean dust concentration was 3·48 mg./m.3 compared with 2·85 mg./m.3 in the card room of the same mill.
The prevalence of byssinosis was 18·8% among the women and 13·8% among the men. A comparison among the women showed that those with symptoms of byssinosis had, on the average, significantly lower F.E.V.s than women of similar age without such symptoms. Four women and one man with moderately severe symptoms of byssinosis showed evidence of permanent respiratory disability with effort intolerance and a substantial diminution in F.E.V.1·0. Further studies should be carried out in other winding rooms because, if these findings are repeated elsewhere, they would indicate the necessity for medical surveillance, dust control, and extending the compensation scheme to include winding room workers.
PMCID: PMC1008542  PMID: 6023077
10.  Prevalence of byssinosis in Swedish cotton mills. 
The prevalence of byssinosis and of chronic bronchitis was studied in a questionnaire investigation among workers in bale opening areas, carding rooms, and spinning rooms in five Swedish cotton mills. Airborne dust and Gram-negative bacteria was measured. Nineteen per cent of the interviewed workers reported symptoms of light byssinosis (grade 1/2). The prevalence of symptoms was not related to the duration of employment, and cases of byssinosis were found among people who had worked in cotton mills for only a few years. A significantly higher proportion of male than female workers reported symptoms. No difference in the extent of byssinosis was found between smokers and non-smokers, but the prevalence was significantly higher among those workers who had ceased smoking. The prevalence of byssinosis was related to the number of airborne viable Gram-negative bacteria as well as to the dust level in the different mills.
PMCID: PMC1008836  PMID: 7236538
11.  Dust in Card Rooms: A Continuing Problem in the Cotton-Spinning Industry 
The results are given of environmental and clinical investigations in four card rooms where one of the latest systems of exhaust ventilation to control dust has been installed. The concentration of air-borne coarse dust particles, larger than 2 mm., was reduced by between 80% and 90% around the carding engines. The card rooms consequently looked less dusty. However, the concentrations of medium and fine sized dust particles were not always reduced and were actually increased in some places. In one mill, when the new control system had been running for three years, there was found to be no reduction in the prevalence of non-specific chest symptoms, and there was an increase in the number of those with chest tightness on Mondays, a symptom characteristic of byssinosis. Evidence is given of a similar failure to reduce the dust sufficiently in three other mills where the same exhaust system is installed.
There is an urgent need to extend the limited investigations reported here to a larger number of mills. Meanwhile there is a continuing morbidity and mortality from byssinosis. Until work in card rooms has been made safe and proved to be so, it is necessary to have regular measurement of dust conditions and for the workers to have periodical medical examinations to enable managements to be advised about the hazards in their mills and advice to be given to the individuals affected by the dust.
PMCID: PMC1038353  PMID: 14180475
12.  Ocular and nasal irritation in operatives in Lancashire cotton and synthetic fibre mills. 
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.
PMCID: PMC1128098  PMID: 7849851
13.  An epidemiological study of respiratory symptoms in Lancashire mills, 1963-66 
Molyneux, M. K. B., and Tombleson, J. B. L. (1970).Brit. J. industr. Med.,27, 225-234. An epidemiological study of respiratory symptoms in Lancashire Mills, 1963-66. An epidemiological study of card and blowroom workers in 14 cotton spinning and two man-made fibre spinning mills in Lancashire has been carried out on a prospective basis of six-monthly examinations over three years. The number of operatives to be included was decided so as to give a sufficient sample for the statistical assessment of fall in FEV, at the same time allowing for population movement. The examination of each worker included a history, a questionnaire of respiratory symptoms, and a measurement of forced expiratory volume in one second. The results in this paper, which will be followed by others on other aspects of the survey, give the prevalence of both byssinosis and bronchitis, according to the definition given, in the 1 359 cotton workers and 227 man-made fibre workers, seen at least once, and also the dust levels in the mills. Eight of the mills processed coarse and six medium cotton.
The total prevalence of byssinosis, as defined, is 26·9%, being higher in coarse than in medium cotton mills, and the occupational groups most affected are strippers and grinders, carders and undercarders, and draw frame tenters. In coarse mills symptoms develop in some men and women within the first four years of exposure, and in medium mills between five and ten years' exposure. Repeat questionnaires in about half the population, two years after the first questionnaire, showed the development of symptoms of chest tightness in an appreciable number not previously affected. The incidence of bronchitis is increased in operatives with symptoms of byssinosis, but is influenced by age and smoking.
Total dust levels averaged 3·1 mg/m3 in coarse miles and 1·2 mg/m3 in medium mills. The findings indicate that dust control measures, though they have produced considerable improvement, are not now fully effective with present methods of production.
PMCID: PMC1009137  PMID: 5448120
14.  Relationships between dust level and byssinosis and bronchitis in Lancashire cotton mills 
Berry, G., Molyneux, M. K. B., and Tombleson, J. B. L. (1974). British Journal of Industrial Medicine,31, 18-27. Relationships between dust level and byssinosis and bronchitis in Lancashire cotton mills. A prospective survey of workers in 14 cotton and two man-made fibre spinning mills was carried out. A questionnaire on respiratory symptoms was completed at the start of the survey by 1 359 cotton workers and 227 workers in man-made fibre mills and again two years later by about half of these workers. Dust measurements were available for 772 women and 234 men cotton workers.
The prevalence of bronchitis was found to be unrelated to dust level but for women was related to years of exposure. The change in symptoms of bronchitis was unrelated to dust level or to length of exposure. There was, however, an increased prevalence of bronchitis in the cotton mills when compared with the man-made fibre mills, and also over the two-year period a greater proportion of symptom-free workers developed symptoms and a lower proportion of those with symptoms lost their symptoms in the cotton mills than in the man-made fibre mills.
The prevalence of byssinosis was related to smoking habits, the smokers having about 1·4 times as much byssinosis as the non- and ex-smokers after allowing for exposure. Byssinosis was associated with the dust level and years of exposure, more so for the women, and an association between the incidence of new cases over the two years and dust level was also found. After allowing for dust level, years of exposure, and smoking there were still differences between the occupational groups in byssinosis prevalence. Strippers and grinders had the highest prevalence followed by drawframe tenters. Speedframe tenters, card tenters, and comber tenters had similar prevalences and ring spinners the lowest.
PMCID: PMC1009538  PMID: 4821407
15.  Respiratory response in simultaneous exposure to flax and hemp dust 
Žuškin, E., and Valíc, F. (1973).British Journal of Industrial Medicine,30, 375-380. Respiratory response in simultaneous exposure to flax and hemp dust. The effect of exposure to high concentrations of mixtures of hemp and flax dust was studied in 124 workers in two textile mills (mill A: 65-70% hemp and the rest flax, mean dust concentration 13·9 mg/m3; and mill B: about 35% hemp and the rest flax, mean dust concentration 15·8 mg/m3). A high prevalence of byssinosis was found in both mills (80% in mill B; 46·8% in mill A) after a mean exposure of no more than 13 years. In both mills, byssinotics had a higher prevalence of all chronic respiratory symptoms than non-byssinotics. This difference was more pronounced in mill A. Forty-eight percent of byssinotic women and 43% of byssinotic men had byssinosis of grade 2 or 3. Significant mean acute reductions in FEV1·0 and ˙Vmax 50% VC on Monday were recorded in subjects with and without byssinosis with a significantly larger mean reduction in byssinotics (FEV1·0, P < 0·01; ˙Vmax 50% VC, P < 0·05). ˙Vmax 50% VC proved to be a more sensitive test for detecting acute effects of vegetable dust than FEV1·0. The acute respiratory response of the subjects exposed to similar concentrations of flax and mixtures of two different proportions of flax and hemp dust was found to be equal.
PMCID: PMC1069478  PMID: 4753721
16.  The Relationship of Byssinosis to the Bacteria and Fungi in the Air of Textile Mills 
The principal causative agent of byssinosis lies in the dust of cotton mills. This dust contains bacteria and fungi. An attempt has been made to determine whether any association could be established between the numbers of viable bacteria and fungi in the air of two cotton and two jute mills, and the prevalence of byssinosis. No association was found except between the numbers of live organisms of B. pumilus and B. subtilis, and the occurrence of byssinosis. This association does not establish a causal relationship, but it is suggested that an attempt should be made to produce typical symptoms in byssinotic subjects by means of organisms of the genus Bacillus. A subsequent paper presents the results of some observations of this kind.
PMCID: PMC1038084  PMID: 13778564
17.  Cotton dust concentrations and particle size distributions associated with genotypes. 
The problem of byssinosis has plagued cotton textile mills for hundreds of years, and it is still a problem today. With the regulations on airborne raw cotton dust set by OSHA and the ACGIH, research regarding the measurement of cotton dust in lint fiber is a necessity. A procedure known as the mass concentration particle size distribution (MCPSD) technique, developed at Texas A&M University, was used to measure the characteristics of cotton dust as affected by harvesting method and genotype. Cotton genotypes from three harvest seasons were analyzed by using a Coulter Counter, Model TAII, to obtain the mass concentrations and particle size distributions of dust present in the lint fiber. The genotypes were subjected to both hand harvesting and conventional spindle harvesting for comparison purposes. Results from the dust concentration analyses of particles less than 100 micron, 16 micron, and 8 micron in diameter, respectively, are presented. Also, a proposed procedure to obtain large quantities of "cotton dust" from gin trash material is discussed.
PMCID: PMC1474383  PMID: 3709480
The same plan of investigation as was used in a previous study of jute workers (Gandevia and Milne, 1965) has been applied to a survey of 50 workers in the blowroom and carding and spinning area of a Sydney cotton mill. Significant decreases in ventilatory capacity were recorded on Friday, Monday, and the following Thursday, with, on the average, complete `overnight' recovery, as indicated by similar morning values. Slightly, but not significantly, greater differences were observed in seven subjects with mild byssinotic symptoms and in five subjects with an observed productive cough on request. No effect of sex, shift, or history of cough and sputum was demonstrable. By contrast with the jute workers, no influence of smoking habit was apparent. The larger decreases in ventilatory capacity were observed in those with the higher F.E.V.1·0:F.V.C. ratios, whereas the reverse trend was noted in the jute workers. The occurrence of significant large decreases in those employed in the industry for less than a month, in conjunction with other evidence, suggests that a factor of `self-selection' may be operative among cotton employees in this country and may be related to the apparently low prevalence of clinically important byssinosis. Attention is drawn to two different patterns of change of ventilatory capacity over a week in subjects exposed to dusts sometimes associated with symptoms of byssinosis; the relationship of these changes and of chronic bronchitis to the development of clinical byssinosis is discussed.
PMCID: PMC1069382  PMID: 5836570
19.  Mill effect and dose-response relationships in byssinosis. 
Four hundred and eighty-six textile workers in three cotton mills and one wool/synthetic mill were studied for symptoms and functional effects of workroom exposure to dust. Byssinosis was found in 5.7% of 386 cotton workers, with an apparent threshold level of 0.5 mg cotton dust/m3 of air. Mean post-shift functional declines were greater in workers exposed to greater than or equal to 0.2 mg/m3. Workers with byssinosis were unequally distributed, however, with respect to job category and mill; and these variables, rather than current dust exposure levels, accounted for the observed distribution of byssinosis prevalence rates. Variation in biological potency of different samples of cotton dust could be responsible for 'mill effect', the residual variation in response rates by mill after controlling for variation due to dust exposure. A number of other potential influencing variables that are likely to be distributed unequally by mill should also be considered. Mill effect should be assessed in large-scale studies of byssinosis, most of which have analysed biological response rates by combining mill and other variables to examine first-order effects of dust dosage. In such analyses, much of the observed variability may be due to factors other than dust dosage.
PMCID: PMC1008608  PMID: 508642
20.  The Size of Cotton Dust Particles Causing Byssinosis: An Environmental and Physiological Study 
Fourteen subjects of whom 12 were cotton mill blow- or card-room workers were exposed in a plastic tent for periods of three or four hours to airborne mill dust either of unrestricted size distribution (total dust) or containing only particles of less than 7μ(fine dust).
A significant fall in indirect maximum breathing capacity followed exposure to either total or fine dust in most experiments. The response to total dust usually appeared a little larger than to fine but the concentration of fine particles in the unfiltered air was rather higher. The changes in the single-breath nitrogen clearance index and the inspiratory airways resistance were less constant, but the general pattern followed that of the ventilatory capacity.
It is concluded that the fine fraction (under 7μ) of cotton mill dust produces changes in respiratory function and may be alone responsible. The findings suggest a direct action by the dust on the smaller air passages and imply that to be completely effective dust suppression measures in cotton mills should remove fine dust.
PMCID: PMC1038125
21.  A study of the acute and chronic changes in ventilatory capacity of workers in Lancashire cotton mills 
Berry, G., McKerrow, C. B., Molyneux, M. K. B., Rossiter, C. E., and Tombleson, J. B. L. (1973).Brit. J. industr. Med.,30, 25-36. A study of the acute and chronic changes in ventilatory capacity of workers in Lancashire cotton mills. A prospective study of workers in 14 cotton and two man-made fibre spinning mills in Lancashire was carried out over a three-year period. A questionnaire on respiratory symptoms was completed at the start of the survey and again two years later. Up to six measurements of ventilatory capacity were made at six-monthly intervals. From these measurements the rate at which the forced expiratory volume (FEV1) was declining (annual decline in FEV) was evaluated for 595 subjects. Six of the mills were visited on Mondays and in 199 operatives the ventilatory capacity was measured at both the beginning and end of the shift to evaluate its acute fall during work (Monday fall in FEV).
The mean annual decline in FEV for cotton workers was 54 ml/year and it was only 32 ml/year for workers in the man-made fibre mills but this lower value was attributable almost entirely to one of the two mills. For the jobs near the carding engines the annual decline was 22 ml/year higher than for speed-frame tenters. The annual decline for cigarette smokers was 19 ml/year greater than for non- and ex-smokers. The annual decline in FEV was not found to be related to symptoms of byssinosis or bronchitis, nor to present dust levels, bioactivity of the dust or air pollution, although the expected effect attributable to byssinosis turned out to be less than that which the survey was designed to detect.
The mean Monday fall in FEV was higher in cotton mills than in man-made fibre mills among those without symptoms of byssinosis and was correlated with present dust levels. For those with symptoms of byssinosis an increased Monday fall was found only in those processing coarse cotton.
For those subjects who completed the respiratory questionnaire on two occasions the chronic and acute changes in FEV were examined in relation to the change in symptoms of byssinosis. No association was found for annual decline in FEV but the Monday fall in FEV was greater for those who developed byssinosis during the survey than for those who remained free of symptoms, and was less for those who lost their symptoms than for those who retained them.
PMCID: PMC1009474  PMID: 4685297
22.  Dust Diseases in Dundee Textile Workers 
A survey of respiratory symptoms and function was carried out in Dundee among 123 men and women in the jute industry and 242 in the flax industry. The selection of workers was biassed in favour of those working in the dustier departments as judged by eye and those in the older age groups. A group of 72 men in a heavy engineering firm were also selected as controls for comparison.
Chronic bronchitis, as defined by Ogilvie and Newell (1957) was recorded in 27% of those interviewed, whose average age was 49. Byssinosis of various grades was recorded in 30% of all working in flax; of these 35 had cough alone worse on Monday, 34 had other respiratory symptoms worse on Monday and in only four persons did the exacerbation persist longer in the week.
In spite of the occurrence of byssinosis, chronic bronchitis was no more prevalent among flax workers than among the others, the average ventilatory function was no worse, and radiographs of the chest revealed no differences. The characteristic fall in expiratory flow rate during the course of exposure to flax dust on Mondays is similar to that found in cotton workers, and is absent in jute workers and in flax workers not admitting to symptoms of byssinosis.
PMCID: PMC1038081  PMID: 13765497
In a rope works handling manila, sisal, and St. Helena hemps, the prevalence of respiratory symptoms and the change in forced expiratory volume (F.E.V.1·0) during the work shift were studied in a group of 41 women and 41 men who represented 93% of the population at risk.
Dust concentrations, measured with a modified Hexhlet, ranged from 0·11 to 4·51 mg./m.3 for total dust and 0·02 to 1·46 mg./m.3 for fine dust. The highest concentrations were found in the preparing rooms, in which the workers, all of whom were women, showed on the average a fall in ventilatory capacity during the shift. The workers in the rope walk, all of whom were men, showed a rise in ventilatory capacity during the shift. The difference between the men and women was statistically significant (p < 0·05). No worker gave a characteristic history of byssinosis, although nine women complained of chest tightness associated with their work.
Undue breathlessness on exertion and persistent cough and phlegm were also more common among the women, but they were on the average 18 years older than the men. When the ventilatory capacities and the prevalence of respiratory symptoms of women rope workers were compared with those of a group of women employed elsewhere in the dockyard, the only significant difference was that the rope workers had more chest tightness associated with their work (p < 0·02).
Exposure of volunteers to St. Helena hemp, which is apparently the most likely of the hard hemps to give rise to respiratory symptoms, caused only a slight fall in ventilatory capacity and a small rise in airways resistance.
A sample of St. Helena hemp assayed on guinea-pig ileum had only a relatively small degree of contractor activity. The evidence suggests that the dusts of hard hemps do not cause byssinosis under the conditions in this factory. However, the irritant nature of the dust indicates the need to prevent total dust levels exceeding about 2 mg./m.3.
PMCID: PMC1008297
24.  Intervention studies of cotton steaming to reduce biological effects of cotton dust 
Merchant, J. A., Lumsden, J. C., Kilburn, K. H., O'Fallon, W. M., Copeland, K., Germino, V. H., McKenzie, W. N., Baucom, D., Currin, P., and Stilman, J. (1974).British Journal of Industrial Medicine,31, 261-274. Intervention studies of cotton steaming to reduce biological effects of cotton dust. Previous exposure chamber studies had suggested that steaming cotton could reduce significantly the levels and the biological effects of cotton dust. Therefore an intervention study using a high capacity steamer was designed to test the effectiveness of this process in a single cotton mill. The mill population was surveyed and dust sampling was completed prior to intervention with steamed cotton. A panel of 62 byssinotics and heavily exposed workers was selected to serve as a test panel while steamed cotton was introduced to the mill. Following the introduction of adequately steamed cotton the mean Monday decrement in forced expired volume in one second among panel members was significantly reduced to half that observed during control trials. Dust levels were also significantly reduced in the initial opening and picking processes but increased significantly in later processes. Re-evaluation of the mill population by work area suggested some improvement in expiratory flow per milligram of dust exposure but a progression in symptoms of byssinosis and bronchitis in later mill processes. It is suggested that steaming may have resulted in removal of some bronchoconstricting property of cotton dust, but that binding of fine dust to the fibre may also occur, resulting in delayed release of fine dust particles. The implications of these observations on environmental control are discussed.
PMCID: PMC1009597  PMID: 4425630
25.  A population study in cotton ginnery workers in the Sudan 
Khogali, M. (1969).Brit. J. industr. Med.,26, 308-313. A population study in cotton ginnery workers in the Sudan. An epidemiological study in cotton ginneries in the Sudan covered 323 permanently employed ginnery workers, a random sample of 35 seasonal farfara workers, and a control group of 24 members of a fire brigade. All the workers studied were men.
The study showed a prevalence of byssinosis (defined as chest tightness starting on return from the annual holiday and continuing for at least three consecutive days) in 20% of the ginnery workers and in 48·6% of the farfara workers. Workers exposed to dust showed a mean fall in F.E.V.1·0 of -0·10 litre during the shift, while workers not so exposed showed a mean rise of +0·23 litre; this difference was statistically significant. The F.E.V.1·0 was adjusted for age and standing height. The adjusted means of F.E.V.1·0 were significantly lower for workers exposed to dust compared with those in the control group.
The workers with byssinosis showed a statistically significant fall in F.E.V.1·0 when compared with all ginnery workers; and a highly significant fall when compared with cotton workers without chest symptoms. An attempt was made to grade the byssinotics according to the extent of fall in F.E.V.1·0 during the shift.
The concentration of fine dust (< 7 μ) was measured in each work place. There was a statistically significant association between the prevalence of byssinosis and the concentration of fine dust when comparing the ginnery and farfara workers. Also, there was a significant relationship between the mean adjusted F.E.V.1·0, the mean fall in F.E.V.1·0, and the fine dust concentration.
PMCID: PMC1008989  PMID: 5346829

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