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1.  Immunological and respiratory changes in coffee workers. 
Thorax  1981;36(1):9-13.
Immunological status and respiratory function were studied in a group of 45 coffee workers. Skin tests with coffee allergens demonstrated the highest percentage of positive reactions to dust collected during emptying bags (40.0%), followed by dust of green (12%) and then roasted coffee (8.9%). Among 34 skin-tested control workers, 14.7% had positive skin reaction to dust collected during emptying bags, but none had positive skin reaction to green or roasted coffee. Serum levels of total IgE were increased in 24.4% of coffee workers and in 5.9% of control subjects. The prevalence of all chronic respiratory symptoms was significantly higher in coffee workers than in control subjects. Coffee workers with positive skin tests to coffee allergen had a significantly higher prevalence of chronic cough (63.6%) and chronic phlegm (72.7%) than those with negative skin tests (32.4% and 23.5% respectively). There was a significant mean decrease over the Monday work shift in the maximum expiratory flow rate at 50% of vital capacity (MEF50: -7.9%) and at 25% vital capacity (MEF25: -17.8%), suggesting an obstructive effect mostly in smaller airways. Coffee workers with positive skin tests to coffee allergens had larger acute reductions in flow rates than those with negative skin tests but the difference was not statistically significant.
PMCID: PMC471433  PMID: 7292386
2.  Respiratory function in coffee workers. 
Respiratory function was studied in three groups of workers employed in processing coffee. The prevalence of almost all chronic respiratory symptoms was significantly higher in coffee processors than in control workers. In each group during the Monday work shift there was a significant mean acute decrease in the maximum expiratory flow rate at 50% vital capacity (VC), ranging from 4.0% to 8.7%, and at 25% VC, ranging from 6.0% to 18.5%. Acute reductions in FEV1.0 were considerably lower, ranging from 1.3% to 2.8%. On Thursdays the acute ventilatory function changes were somewhat lower than on Mondays. Acute decreases in flow rates at low lung volumes suggest that the bronchoconstrictor effect of the dust acts mostly on smaller airways. Administration of Intal (disodium cromoglycate) before the shift considerably diminished acute reductions in flow rates. A comparison of Monday pre-shift values of ventilatory capacity in coffee workers with those in controls indicates that exposure to dust in green or roasted coffee processing may lead to persistent loss of pulmonary function.
PMCID: PMC1008526  PMID: 111700
3.  Effects of fluorocarbon propellants on respiratory flow and ECG. 
Ten subjects were exposed to the propellants freon 11, freon 12, freon 114, to two mixtures of freon 11 and 12 and to a mixture of freon 12 and 114. The length of exposure was 15, 45 or 60 seconds. Maximum expiratory flow-volume (MEF) curves and ECG were recorded before, and intermittently up to 1 hour after, exposure. Breathing level concentrations of propellants during exposure were determined by gas chromatography. All freons induced biphasic reduction of ventilatory capacity on inhalation. The first fall occurred within a few minutes of exposure while the second was delayed 13-30 minutes after exposure. The effects of mixtures were greater than those of individual freons. The relative fall in MEF 75% was more pronounced than that in MEF 50%. No clear-cut pathological changes in ECG were found. Nevertheless, most subjects developed variations in heart rate exceeding those noted before exposure. In a few cases inversion of the T wave, and in one case atrioventricular block, were observed.
PMCID: PMC1008194  PMID: 871444
4.  Lung function in textile workers. 
Acute changes in ventilatory function during a workshift with exposure to hemp, flax, and cotton dust were measured on Mondays in a group of 61 textile workers, all working on carding machines. In addition, single-breath diffusing capacity (DLCOSB) was measured before dust exposure on Monday in 30 of the 61 workers. Large acute reductions during dust exposure were recorded in maximum expiratory flow rate at 50% VC (MEF50%), ranging from 38 to 22%. Acute reductions of FEV1-0 were considerably smaller, ranging from 17 to 9%. There was a statistically significant increase in residual volume (RV) with very small and insignificant changes in total lung capacity (TLC). Although preshift FEV1-0 and FVC were decreased, DLCOSB was within normal limits. Plethysmographic measurements in six healthy volunteers exposed to hemp-dust extract confirmed the results obtained in textile workers, that is, that TLC does not change significantly during dust-induced airway constriction and that maximum expiratory flow rate at 50% VC (MEF50%) is a more sensitive test than FEV1-0 in detecting acute ventilatory changes caused by the dust extract.
PMCID: PMC1008077  PMID: 1103956
5.  Pharmacological prevention of acute ventilatory capacity reduction in flax dust exposure 
Valić, F., and Žuškin, E. (1973).British Journal of Industrial Medicine,30, 381-384. Pharmacological prevention of acute ventilatory capacity reduction in flax dust exposure. 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 (FEV1·0) was reduced by 50% and the fall in maximal flow rate at 50% vital capacity (V̇max 50% VC) by over 65%.
PMCID: PMC1069479  PMID: 4148157
6.  Respiratory changes in two groups of flax workers with different exposure pattern 1 
Thorax  1973;28(5):579-583.
Zuskin, E., and Valić, F. (1973).Thorax, 28, 579-583. Respiratory changes in two groups of flax workers with different exposure pattern. A high mean total concentration of flax particles (16·9 mg/m3), of which about 20% were of respirable size, caused a high prevalence of bysinosis (69·9%) in 55 non-smoking female workers exposed to biologically retted flax over an average period of 11 years. A significant mean FEV1·0 decrease over the first work shift after the weekend break was recorded in both byssinotics and non-byssinotics but was more pronounced in the former. The mean acute FEV1·0 reductions over a work shift were smaller on the third than on the first day in the week.
Significant decreases in FEV1·0 and in maximum expiratory flow rate at 50% of vital capacity over the Monday work shift were recorded in a group of 17 seasonal male workers who had been exposed to flax for only two to three months each year for no more than three years.
A high prevalence of chronic cough, chronic sputum production, and chronic bronchitis was found in the female flax workers, especially among the byssinotics.
PMCID: PMC470081  PMID: 4784378
7.  Histamine-releasing activity and bronchoconstricting effects of sisal 
Nicholls, P. J., Evans, E., Valić, F., and Žuškin, E. (1973).British Journal of Industrial Medicine,30, 142-145. Histamine-releasing activity and bronchoconstricting effects of sisal. Extracts of dry and oiled sisal released histamine from pig and human but not from rat lung tissue. A suspension in Tyrode solution of the oil used for softening the sisal fibres had a pH of 8·1 and also released histamine from pig and human lung. The releasing activity was abolished when the pH of this suspension was adjusted to pH 7·4. As all the sisal extracts were adjusted to pH 7·4 for incubation with lung tissue, the histamine-releasing activity of sisal in vitro is unrelated to the presence of the oil.
Significant (P < 0·01) mean reductions over the work shift of ventilatory capacity (PEF and FEV1·0) were recorded in all the workers exposed to airborne sisal dust. These reductions were greater in combers than in drawers and spinners. Sisal collected from combing machines possessed more histamine-releasing activity than material from drawing and spinning machines.
These results indicate that histamine release by sisal may be the cause of acute ventilatory capacity changes in sisal exposure.
PMCID: PMC1009496  PMID: 4122162
8.  Respiratory symptoms and ventilatory function changes in relation to length of exposure to cotton dust 
Thorax  1972;27(4):454-458.
The prevalence of byssinosis, respiratory symptoms, acute changes of ventilatory capacity over the shift, and chronic changes of ventilatory capacity were studied in two groups of non-smoking female workers exposed to practically identical concentrations of the same type of cotton dust but for very different periods of time (16 and 4 years respectively). The prevalence of non-specific respiratory symptoms increased with the duration of exposure to cotton dust only in the subjects with byssinosis. Exposure to cotton dust caused significant reductions over the shift of the mean FEV1.0, FVC and PEF in all the groups of cotton workers examined. In byssinotics the reduction in ventilatory capacity was considerably greater in subjects with longer than in those with shorter exposure to cotton dust, while in non-byssinotics the response was approximately equal in the two groups. Inhalation of a bronchodilator at the end of the shift restored ventilatory function to its pre-shift values except in byssinotics with a longer duration of exposure to cotton dust. Chronic changes of ventilatory capacity developed only in subjects with a longer exposure to cotton dust and were common in the byssinotics.
PMCID: PMC469950  PMID: 5075615
9.  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
10.  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
11.  Peak flow rate in relation to forced expiratory volume in hemp workers 
Žuškin, E., and Valić, F. (1971).Brit. J. industr. Med.,28, 159-163. Peak flow rate in relation to forced expiratory volume in hemp workers. Measurements of the forced expiratory volume in one second (FEV1·0) and the peak expiratory flow rate (PEF) were made in 99 non-smoking female hemp workers before and after the shift. A significant mean reduction of both FEV1·0 and PEF (P<0·01) over the shift was found in workers both with and without byssinosis but the relative reductions of PEF were more pronounced (FEV1·0 15·3%; PEF 20·8%). There was a significant positive correlation (P<0·01) both between absolute FEV1·0 and PEF values measured before work (with byssinosis r = 0·605; without byssinosis r = 0·461), and between FEV1·0 and PEF changes over the shift (with byssinosis r = 0·725; without byssinosis r = 0·631). There was also a significant correlation between FEV1·0 and PEF changes following Alupent inhalation after the shift with more pronounced effects on PEF. The coefficients of variation in FEV1·0 and PEF measurements (by the Bernstein type spirometer and the Wright peak flow meter) proved approximately equal.
PMCID: PMC1009260  PMID: 5572683
12.  Byssinosis, Chronic Bronchitis, and Ventilatory Capacities in Workers Exposed to Soft Hemp Dust 
A study was made of 93 women and 13 men employed in the spinning department of a factory in Yugoslavia processing soft hemp (Cannabis sativa). There were seven occupational groups, with average concentrations of total airborne hemp dust ranging from 2·9 mg./m.3 to more than 19·5 mg./m.3. Thirtyeight women and 11 men, employed in other departments of the factory with average total dust concentrations below 1·0 mg./m.3, were studied as controls.
In the spinning department 40·6% of the workers had byssinosis and 15·1% had chronic bronchitis (defined as persistent cough and phlegm on most days for as much as three months each year during the last two years). None of the controls suffered from either disease.
After adjustment for age, sitting height, and sex, the F.E.V.0·75 and F.V.C. measured at the beginning of the shift were used to assess the long-term effects of hemp dust on the ventilatory function of the lung. The age-adjusted ratio F.E.V.0·75/F.V.C. was also used. A comparison between the control group and the seven exposed groups showed no meaningful association between ventilatory function and present levels of dust exposure, but byssinotics with chronic bronchitis had a mean age-adjusted F.E.V.0·75/F.V.C. ratio significantly lower than that of workers with neither disease (P<0·05).
Acute effects of hemp dust, measured by the change in F.E.V.0·75 and F.V.C. during the shift, were considerable. There were marked reductions in the mean F.E.V.0·75 and F.V.C. during the shift in all the occupational groups exposed to high concentrations of dust. Byssinotics with chronic bronchitis had a significantly greater mean decrease in F.E.V.0·75 during the shift than the byssinotics without chronic bronchitis, and the workers with neither disease (P<0·02).
There is no doubt that the dust of Cannabis sativa hemp can cause byssinosis and at least temporary impairment of ventilatory function, varying in severity according to the level of dust exposure and the presence of respiratory disease.
PMCID: PMC1008770  PMID: 5663421
The effects of the following drugs on urinary coproporphyrin estimations were studied: fouadin, tartar emetic, coramine, emetine hydrochloride, carbon tetrachloride, hexylresorcinol, and atebrin. None of these substances interferes directly with the fluorimetric determination of urinary porphyrin if porphyrin is extracted from urine by ether or ethyl acetate and subsequently re-extracted into the aqueous phase with hydrochloric acid.
Persons under treatment with tartar emetic showed a significantly higher coproporphyrin excretion. For this reason the coproporphyrin test for abnormal lead absorption is likely to be unreliable in persons treated with tartar emetic.
PMCID: PMC1008304
14.  Byssinosis in the Egyptian Cotton Industry: Changes in Ventilatory Capacity during the Day 
A study in Egypt of 99 male cotton workers in a cotton ginnery and spinning mill, and of a control group of 12 power station workers, showed that the groups exposed to cotton dust had significantly greater falls in indirect maximum breathing capacity (I.M.B.C.) during the shift than groups not exposed to dust. Long-term effects of exposure to cotton dust were studied by examining the I.M.B.C.s measured at the beginning of the shift after adjustment to allow for differences in age and sitting height. The adjusted mean value for those with byssinosis was 10·1 litres/min. lower than for normal cotton workers and 19·6 litres/min. lower than for the power station workers. Four men were judged by their breathlessness on slight exertion and low ventilatory capacities to be seriously disabled with byssinosis.
In four other mills, all spinning similar types of cotton, changes in I.M.B.C. during the shift correlated highly with dust concentrations and indicated a safe level of dustiness of 1 mg./m.3 (total dust) at which the effects on ventilatory capacity were minimal.
PMCID: PMC1039190  PMID: 14106129

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