Flax Dust Research Articles

Comparative study of pulmonary function in human beings exposed to cotton fiber and non-exposed human beings

Introduction: Byssinosis is a breathing disorder that occurs in some individuals with exposure to raw cotton dust; and also in people who work in flax or hemp dust. It is a worldwide and popular occupational disease. Characteristically, workers exhibit shortness of breath and feeling of chest tightness when returning to work after a holiday. Pulmonary function testing (PFT) is important for early identification of workers experiencing breathing problem that may be related to their work place. Aim: To bring to light the importance of health among the daily wage earners like the cotton workers to avoid sickness and also the employers to decrease the casualities and labour hours. Materials and Methods: This is a comparative study which was conducted on human male and female subjects comprising of 150 apparently healthy cotton dust workers of ages ranging from 20-30 (Group-I), 30-40 (Group-II) and 40-50 (Group-III) years and an equal number of healthy human beings of same age not exposed to cotton dust. Pulmonary function tests (PFT) namely Forced vital capacity (FVC), Forced expiratory volume in one second (FEV1), Forced expiratory flow (FEF25-75%) and Forced expiratory volume percentage (FEV1 %) were assessed by computerized spirometry. Statistical comparison was done by using the student t-test. Results: There is a significant decrease in pulmonary function tests FVC, FEV1, FEF 25-75%, FEV1% in human beings exposed to cotton fiber when compared to controls. Keywords: Byssinosis, FVC, FEV1, FEF 25-75%, FEV1%, Spirometry.

Microbial contamination of flax dust

Abstract Byssinosis is an occupational lung disease associated with the inhalation of organic vegetable fibres, and despite the fact that it has been recognised for almost 300 years, there is still uncertainty about its aetiology. Cotton byssinosis has been studied extensively; by comparison there is a paucity of information relating specifically to flax byssinosis. Much of the investigative work with cotton has been directed towards identification of microbial contamination of the plant material, consequently gram negative bacteria (GNB) and their endotoxins have been implicated. The object of this study was to investigate the microbial contamination of local flax dust, particularly the GNB content and associated endotoxin levels. The results indicated that flax dust is contaminated by gram positive and gram negative bacteria and by fungi. The average number of GNB was 2.2×109 c.f.u. per gram, and the genera identified were Enterobacter, Pseudomonas, Klebsiella and Acinetobacter. The average endotoxins content of the flax dust was 92 μg/g. Flax and cotton are contaminated by similar species of GNB that produce endotoxin. This lends support to the microbial theory of byssinosis and suggests that these microbes may represent a common denominator.

Investigation of organic dust detonation in the presence of chemically inert particles

The results of experimental studies of organic dust detonation in the presence of chemically inert particles are presented. Tests were carried out using a vertical detonation tube, and direct streak pictures showing the flame acceleration and pressure and temperature records were obtained. Flax dust, dispersed in an oxygen atmosphere, was used as the fuel, and two kinds of quartz sand were introduced as nonreacting particles. It was found that addition of inert particles caused a linear decrease of the detonation wave velocity but had no special influence on the transition distance. Calculations using the Gordon McBride Code Showed that propagation of the detonation wave in a dust-oxygen mixture requires that the dust particles burnout at a level of about 70% but addition of inert particles increased the necessary burnout level to over 80% (with a significant decrease of the detonation wave velocity).

Isolation, Enumeration, and Identification of Gram Negative Bacteria from Flax Dust with Reference to Endotoxin Concentration

The object of this study was to investigate the microbial contamination of flax dust in the linen industry, particularly the gram negative bacteria (GNB) content and associated endotoxin levels. Standard bacteriological techniques were used. The results obtained were contrasted with studies in the cotton industry. The microbial flora of cotton and flax is similar but greater GNB contamination, with consequently higher endotoxin levels, was found in flax. Flax byssinosis and cotton byssinosis may share a common microbial etiology.

Isolation, Enumeration, and Identification of Gram Negative Bacteria from Flax Dust with Reference to Endotoxin Concentration

Isolation, Enumeration, and Identification of Gram Negative Bacteria from Flax Dust with Reference to Endotoxin Concentration

Immunological findings in hemp workers

Immunological status and its relation to respiratory findings were studied in 42 female textile workers occupationally exposed to hemp dust and in 49 female control workers. Skin prick tests with hemp or flax dust extracts from different parts of the mill in hemp workers demonstrated the following frequencies of positive tests to antigens: a mixture of hemp and flax extracts (64%), followed by flax extracts (48%), hemp from combing machines (41%), hemp from carding machines (38%), hemp from spinning and weaving machines (33%), and hemp from softening machines (20%). The prevalence of positive skin tests to hemp or flax allergens in control workers was consistently lower, ranging from 21 to 5%. Increased total serum IgE was recorded in 35.7% of hemp workers compared to only 5.0% of control workers (P < 0.05). Hemp workers with positive skin tests had significantly higher prevalences of chronic respiratory symptoms than those with negative skin tests. There were, however, no differences for acute symptoms between workers with positive and negative skin tests. Across-shift changes and baseline lung function were not different when compared by immunologic status. We showed additionally that a water-soluble extract of hemp dust causes a dose-related contraction of nonsensitized guinea pig tracheal smooth muscle when studied in vitro. Our results suggest that frequent immunologic abnormalities can be documented in hemp workers but, with the exception of chronic respiratory symptoms, in general, these do not correlate with respiratory findings.

Branchial challenge of normal subjects with the endotoxin of Enterobacter agglomerans isolated from cotton dust.

Endotoxin produced by a culture of Enterobacter agglomerans isolated from cotton dust was inhaled by 12 normal subjects. No significant airway constriction was obtained in doses equivalent to those experienced in a workshift in a dusty mill. There was a statistically significant difference between this result and the bronchoconstriction that had occurred after flax dust inhalation in the same subjects. It is suggested that Enterobacter agglomerans endotoxin is not the causative agent of the acute bronchoconstriction that follows inhalation of textile dust.

Identification of hazards caused by static electricity in dust chambers

Electrostatic charges can accumulate in filter sacks. Moreover electrostatic discharges can occur inside filter sacks during shacking or cleaning them with compressed air. Various filter cloths and flax dust were investigated. Material parameters as well as the parameters of electrostatic discharges were investigated on laboratory stands. Investigations allowed comparison between various filter cloths from the view point of hazards caused by static electricity in dust chambers.

Identification of hazards caused by static electricity in dust chambers

A dust chamber is a room containing filtration sacks which are the final elements of dedusting chains. There is a real possibility of formation and retention of explosive dust-air mixtures in these chambers. In conjunction with this the problem arises of explosion initiation by electrostatic discharges. It was known so far that the dust becomes electrically charged in the processes of transport, pulverization and separation. Basing on material investigations and on comparative measurements of electrostatic fields outside filtration sacks, it was also possible to observe accumulation of electrostatic charges in filtration sacks. However, direct information on forming of electrostatic discharges, particularly inside sacks in conditions of dust layer separation was lacking hitherto. The problem outlined above was investigated experimentally on flax dusts. An indicator of electric discharges has been constructed and used for detection of spark discharges during separation of dust layers inside filtration sacks. The nature of the discharges was investigated on the laboratory stand and the discharge currents were recorded. Several parameters inclusively those of the equivalent discharge circuit were introduced for characterization of these discharges, basing on earlier own work. The applied investigation method allowed comparison between various filtration fabrics from the view-point of hazards caused by static electricity in dust chambers, which can find direct practical application when materials for filtration sacks are chosen.

Role of histamine in the aetiology of byssinosis. II. Lung histamine concentrations in guinea pigs chronically exposed to cotton and flax dusts.

Data presented in this study support the finding that cotton and flax dusts contain agents which potentiate the formation or accumulation of histamine or both in the lungs of guinea pigs exposed to dust, and that such agents are present at much higher levels in cotton dust than in flax dust. The potentiating effect may be through the recruitment of mast cells into the lung. Both cotton and flax dusts contain methylating enzyme inhibitory agents, whereas cotton dust also contains agents that inhibit histaminase activity; flax dust contains agents potentiating histamine activity. These agents working together result in the accumulation or depletion of histamine observed in the different groups of animals exposed to either cotton or flax dust in this study.

Role of histamine in the aetiology of byssinosis. I Blood histamine concentrations in workers exposed to cotton and flax dusts.

The formation or the accumulation, or both, of histamine in the lungs may be potentiated by agent(s) present in cotton dust at higher level(s) than in flax dust and negligible in cottonseed dust. It has been suggested that such potentiation may be due to the activation of the ability of the lung to produce histamine and/or produce or recruit mast cells; this may present an acceptable explanation of the mechanism by which the propagation of the chronic effect of the dust proceeds in cotton and flax workers. Histamine accumulated in the lung over the weekend is released on exposure to dust causing the symptoms of byssinosis. The difference in the rate of histamine metabolism relative to the rate of histamine formation in byssinotic subjects leads to a more prolonged histamine accumulation than in symptom free subjects, with the consequent appearance of the symptoms of byssinosis. Continuous exposure to dust, without weekend interruption, leads to equivalent rates of histamine formation and metabolism with non-considerable histamine accumulation in the lungs and consequent absence of the symptoms of byssinosis.

Alteration of mast cell cyclic AMP levels and its relationship by byssinosis.

Alteration of mast cell cyclic AMP levels have been implicated in the acute respiratory symptoms in mill workers following inspiration of cotton, flax, or hemp textile dusts. This paper describes the inverse relationship between the cellular levels of cyclic AMP and the degranulation in pure culture of mast cells in response to aqueous cotton bract extracts of glanded and glandless varieties.

THE FLAX INDUSTRY IN NORTHERN IRELAND TWENTY YEARS ON

In 1961-62 a survey of respiratory symptoms in 2528 workers in flax mills in Northern Ireland and of dust levels in the mills was conducted. The workers were followed up in 1978, because recent developments suggested that an upturn in the industry was likely. Flax dust has an acute, reversible effect on the respiratory system, and byssinosis is a prescribed disease under the Industrial Injuries Act (1965). However, the follow-up study found no evidence of an effect on survival of either exposure to dust or byssinosis. The number of applications to compensation panels for assessment and certification of byssinosis has increased greatly in Northern Ireland. Although certification is independent of any subsequent common law claim by a worker for compensation on the grounds of disablement consequent on negligence by his employer, it must weigh heavily in such a claim. About 50 common law claims have been settled out of court for large sums in Northern Ireland, and 950 claims are waiting to be heard. The future cost to the industry is estimated to be at least £16 million. Since byssinosis appears not to cause excess mortality, it is unlikely to cause serious long-term morbidity. Although workers should be compensated for disablement due to negligence, in the absence of unequivocal evidence of disablement caused by byssinosis the financial settlements being reached in Northern Ireland seem unreasonable.

Collection of Large Quantities of Respirable Cotton Dust for Byssinosis Research

Byssinosis is an occupational respiratory disease which is thought to be induced by chronic respiration of cotton, flax, or soft-hemp dusts in textile mills. The disease is caused by foreign matter included with the raw fiber, not by the fiber. Obtaining sufficient quantities of respirable dust under 15–20 μm diameter for biological and chemical analysis has been a major difficulty in byssinosis research. Two simple means have been devised for collecting kilogram quantities of respirable cotton dust from the air-cleaning systems in commercial mills.

A physiological study of byssinosis in colonial America.

AbstractWe assessed the acute effects of inhalation of flax dust, produced during processing of flax fibers under conditions similar to those in colonial America. Exposure to this dust, for about 5 hours, caused minor symptoms of chest tightness in five healthy persons, accompanied by decreases of maximum expiratory flow rates, indicating acute small airway obstruction. Measurements of flow rates on partial expiratory flow‐volume (PEFV) curves were more sensitive than flow rates on MEFV curves and FEV1.0 in assessing constrictor effects of flax dust, even though flow rates on flow‐volume curves are more variable under control conditions than the FEV1.0. Thus, acute symptoms of byssinosis may have been prevalent among early settlers in America who processed flax in their barns. Since these barns were used for many other purposes as well, children and other farm workers were probably also at risk.Ramazzini's observations on the flax and hemp workers of Northern Italy were, for obvious reasons, not accompanied by objective evidence concerning the effects of flax and hemp dust on the lungs. Since 17th‐century working conditions are being recreated in historical restoration projects, and modern function tests are available, such objective evidence can now be obtained. With the revival of primitive crafts in our times, this is of some practical importance.The primitive methods used for fiber processing in Ramazzini's time are demonstrated every day at Philipsburg Manor, North Tarrytown, New York. Philipsburg Manor is a restoration project, dedicated to a historical interpretation of life among early Dutch settlers in the Hudson Valley. A recent field study on this site provided an opportunity to assess the acute effects of flax dust on the lungs of people who process flax fibers with primitive methods and on the lungs of others who are exposed to flax dust in the same environment.

Respiratory response in simultaneous exposure to flax and hemp dust.

Abstract Žuskin, E., and Valic, 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.

Pharmacological prevention of acute ventilatory capacity reduction in flax dust exposure.

<b>Valić, F., and Žuškin, E. (1973).</b><i>British Journal of Industrial Medicine,</i><b>30,</b> 381-384. <b>Pharmacological prevention of acute ventilatory capacity reduction in flax dust exposure.</b> The protective effect of the preshift application of a bronchodilator (orciprenaline), an antihistamine drug (diadril), and ascorbic acid on flax-induced acute bronchoconstriction was studied in 13 byssinotic and 7 non-byssinotic female workers exposed to airborne fibres of biologically retted flax. Orciprenaline was applied by inhalation, while diadril and ascorbic acid were given orally. All the three drugs exerted a significant preventive effect, diminishing the acute fall of ventilatory capacity during the shift. The fall in forced expiratory volume (FEV_1·0) was reduced by 50% and the fall in maximal flow rate at 50% vital capacity (V̇_max 50% VC) by over 65%.

Study of lung function changes among different grades of byssinosis.

<b>El-Sadik, Y. M., Moselhi, M., El-Hinady, A. R., and Mostafa, M. N. (1972).</b><i>Brit. J. industr. Med.,</i><b>29,</b> 184-187. <b>Study of lung function changes among different grades of byssinosis.</b> This study comprised 80 workers of whom 50 are byssinotics, 15 are chronic asthmatic bronchitics, and 15 are free of chest symptoms. A comparison of the changes in forced expiratory volume in one second due to exposure in the first working day in the week among them (80 workers) showed a greater reduction in byssinotics than among the others. Reduced maximum expiratory flow rates were found only in byssinotics. Independent of exposure, only third-grade byssinotic cases (22 out of 50) showed changes in predicted vital capacity, residual volume, total lung capacity, three seconds per cent vital capacity, total vital capacity timed in seconds, and air velocity index. The pattern of changes in these lung functions is mostly obstructive; only two cases showed the pattern of restrictive disease. This study denotes that two types of changes in pulmonary functions occur due to byssinosis. The first type is a temporary change in pulmonary functions which occurs only on exposure to the aetiological factor (cotton or flax dust). This type occurs among all grades of the disease. The nature of this type is obstructive. The second type of change is permanent. This type occurs only among the third grade of the disease and is not dependent on immediate exposure. This type of change is mostly obstructive but may show some restriction.

BYSSINOSIS PREVALENCE AND FLAX PROCESSING.

Previous evidence suggested that byssinosis in flax workers is caused by the inhalation of dust of biologically retted flax. In the present study no cases of byssinosis were found among workers in a flax plant which produces yarn by chemical degumming instead of biological retting. The absence of byssinosis in this plant could not be attributed to differences in the quantities of dust developed as compared with the conventional retting procedure. These findings support the view that the agent in flax dust which causes symptoms of byssinosis originates during biological retting of flax and is absent from unretted flax. Chemical degumming of flax appears to be superior to biological retting procedures with respect to the health of the workers.