Ventilatory function of factory workers exposed to tea dust.

A cross-sectional study was conducted in order to determine the prevalence of respiratory symptoms and the effect on ventilatory capacity in workers exposed to tea dust for at least five years during the sifting process of tea manufacture compared to a control group of field workers who were not exposed to tea dust previously. Fifty-three subjects each in the study and control groups were matched for age, sex, ethnic group and height. Prevalence of chronic respiratory symptoms was obtained by questionnaire. Spirometric measurements included forced vital capacity (FVC), forced expiratory volume in the first second (FEV1.0) and forced mid-expiratory flow rate (FEF 25-75%). The study group had a chest radiograph. The odds ratio for any chronic respiratory symptom was 11.6 (95% confidence interval [CI] = 3.7-39.4) in the study group. Mean values for the spirometric tests were lower in the study group; the differences in FEV 1.0 and FEF 25-75% were significant. Tuberculosis was not found in the study group, while one subject (2.4%) had radiological evidence of bronchiectasis. It may therefore be concluded that chronic tea dust exposure causes increased prevalence of respiratory symptoms and a significant degree of small airways obstruction.

Spirometric and flow standards for healthy adult non-smoking Sri Lankans belonging to the Sinhalese ethnic group.

The objective of this study was to establish reference norms for dynamic lung volumes and forced expiratory flows applicable to the Sinhalese ethnic group in Sri Lanka. Respiratory function tests were carried out on 367 female and 328 male healthy non-smoking Sinhalese adults of age range 17-65 years. Subjects included hospital and university staff, students of the Faculty of Medicine at Peradeniya and healthy relatives accompanying patients to outpatients clinics. An 8-litre rolling-seal spirometer was used in conjunction with a X-Y recorder. Forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1) reached a peak at 30 years in males and 23 years in females. All measurements except forced mid-expiratory flow (FEV25-75%) increased with increasing height. The flow-volume curve became progressively concave towards the volume axis with advancing age. Lung function measurements correlated best with age and height. Therefore prediction formulae were developed with these two measurements as the independent variables. Nomograms based on these formulae were constructed. When standardized for height and age, forced expiratory volumes were smaller than in Europeans, Negroes and Pakistanis, and were comparable to South Indian data. However, flows did not vary significantly from those of other ethnic groups. It can therefore be concluded that the Sinhalese have smaller lungs than Europeans and Negroes even after adjustment for differences in stature, but lung elastic recoil pressure and airway calibre (which are determinants of forced expiratory flows) appear to be similar to those of other ethnic groups.

Peak expiratory flow rate in Sri Lankan schoolchildren of Sinhalese ethnic origin.

Normal values for lung function indices are not available for Sri Lankan children. Reference standards for peak expiratory flow rate (PEFR) in non-smoking Sri Lankan schoolchildren belonging to the Sinhalese ethnic group have been derived. A total of 1206 schoolchildren of age range 5-19 years was studied. The mini-Wright peak flow meter was used to measure peak expiratory flow rates. The highest of three readings was taken as the correct value. The results were correlated with age, standing height, weight and surface area. The flow rate was only marginally higher in pre-pubertal boys than in girls. Girls reached a maximum at 15 years of age. The boys continued to show an increase in the PEFR until, at the age of 19 years, they had values about 150 l min-1 higher than females of the same age. Up to a height of 150 cm, a weight of 35 kg and l.1 m2 surface area, the two sexes showed similar gradients of increase of PEFR. Beyond these limits, the relationships changed abruptly, the boys showing an increase and the girls, a decrease in the gradient. There was a high correlation between PEFR and the anthropometric measurements studied. The peak flow rates compared favourably with those of other ethnic groups. Prediction formulae were developed with age and height as the independent variables. A nomogram based on these equations was constructed. These results would be useful in obtaining predicted normal values in Sinhalese school children with respiratory dysfunction.

An epidemiological study of the health of Sri Lankan tea plantation workers associated with long term exposure to paraquat.

Pulmonary function tests (FVC, FEV1, FEV1/FVC%, TLCO, single breath CO diffusion), chest x ray film, renal function (serum creatinine and blood urea nitrogen), liver function (serum alanine aminotransferase, aspartate transferase, and alkaline phosphatase, bilirubin, total protein, and albumin), a haematological screen (haemoglobin and packed cell volume), and a general clinical examination were performed on 85 paraquat spraymen (mean spraying time 12 years) and on two control groups (76 factory workers and 79 general workers) frequency matched for age and years of occupational service. All the subjects were men. There were no clinically important differences in any of the measurements made between the study group and the two control groups. In particular the results of the lung function tests, appropriate for paraquat toxicity of the study group, were similar to those of the control groups. The same was true of blood tests for liver and kidney function. The incidence of skin damage, nose bleeds, and nail damage in the study group was slightly higher than in the control groups but lower than the incidence reported for paraquat workers in previous studies. The results of this study confirmed that long term spraying of paraquat, at the concentrations used, produced no adverse health effects, in particular no lung damage, attributable to the occupational use of the herbicide.

The effect of capsaicin on the small intestinal absorption of glucose and alanine in the rat.

Chilli (containing the active ingredient capsaicin) forms an important flavouring agent in the preparation of meals in the tropics. Previous studies have shown that capsaicin in high doses causes gross structural and functional changes in the gut. The present study investigates the effect of pure capsaicin on the absorption of glucose, water and alanine by the small intestine of the rat. Perfusion studies were carried out using a 10 cm jejunal segment. Absorption rates of glucose, water and alanine from a control solution containing the nutrient and from a test solution containing added capsaicin were compared. Recovery of absorptive function of the intestinal mucosa after exposure to capsaicin was also studied. Absorption of water, glucose and alanine was found to be significantly reduced in the presence of capsaicin. Recovery of absorptive function occurred when capsaicin was withdrawn from the perfusate. It was concluded that capsaicin adversely affected absorption of nutrients from the rat small intestine; this effect was reversible at least in the case of some nutrients.

Diuretic effect of Aerua lanata with water, normal saline and coriander as controls.

The extract (200 ml of 50 g/L) of common garden herb (in Sri Lanka) Aerua lanata (S. Polpala, T. Thengapookeerai) induced diuresis, consistent ovet four repetitions in 70% of the subjects. The rest of the subjects needed higher concentration of the solution (100 g/L), to induce diuresis. The urine output observed with the fresh plant extract was significantly elevated (P less than 0.001) when compared with controls who received the same quantities of water, 0.9% saline of extracts of the seeds of another medicinal plant, Corlandrum sativum. Raw flowers of Aerua lanata were found to be the most effective in inducing diuresis when compared to the other parts of the raw plant and its dried form.