A random sample of 342 workers engaged in chipping and grinding of agate stones were surveyed in a cross-sectional study to assess the prevalence of respiratory morbidity in the agate industry. The findings were compared with those obtained in controls. The study showed a significantly higher prevalence of lung diseases among agate workers than among controls (63.4% vs 35.5%, P less than 0.001). The respiratory morbidity in agate workers and controls was maximal in the group aged 31+ years (83.3% and 42.2%, respectively). The prevalence of pneumoconiosis in agate workers (18.4%) was highly significant as compared with controls, in whom not a single case was found (P less than 0.001). However, there was no significant difference between the prevalence of pneumoconiosis in men and women of the exposed group (17.9% vs 19.6%). Among the cases of pulmonary diseases in agate workers, pneumoconiosis formed the largest group (18.4%), whereas among controls it was tuberculosis (12.1%). The prevalence of pulmonary tuberculosis was very high in both agate workers and controls (15.5% and 12.1%, respectively), probably because of poor socio-economic and unhygienic living conditions. The prevalence of chronic bronchitis was found to be higher among the control population as compared with the exposed group (6.7% vs 2.6%). It therefore appeared that agate dust had no role in precipitating chronic bronchitis. However, bronchial asthma appeared to have been aggravated due to agate dust, as the risk among agate workers was 7-fold that found among the controls. The prevalence of pneumoconiosis showed a dose-response relationship in both male and female agate workers.(ABSTRACT TRUNCATED AT 250 WORDS)

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Spirometric lung functions were evaluated in 220 asymptomatic glass bangle workers exposed to the salts of various heavy metals, such as arsenic, lead, zinc, copper, manganese, cobalt, cadmium, and selenium, which are used as coloring agents in the manufacture of glass bangles. The mean values of various spirometric variables (viz. FVC, FEV1, IMBC, and PEFR) were within normal range (more than 80% of the predicted values) in both smoking and nonsmoking glass bangle workers and did not reveal any significant differences in comparison with those observed in the unexposed controls. However, variables such as FEV1/FVC% ratio, FEF25-75 and FEF75-85 were reduced significantly (p less than 0.001) in the exposed group. The reduction was more marked in the smoking glass bangle workers indicating additive effect of cigarette smoking on the small airways. The exposed group showed a significantly higher prevalence (16.3%) of respiratory impairment in comparison to that observed in the controls (7.9%) as a result of exposure to various metals in the work environment (p less than 0.01). The respiratory impairment observed in the exposed group indicated primarily restrictive pattern of pulmonary abnormality (10.4%), while the controls revealed only 1.1% prevalence of this disease (p less than 0.001). The effect of the duration of exposure on the prevalence of respiratory impairment in the glass bangle industry revealed significantly higher prevalence (p less than 0.05) in those who worked for more than 10 years (23.0%) than in those who worked for less than 10 years (10.8%) thereby indicating that the duration of exposure is directly related to the prevalence of respiratory impairment.

Pulmonary function studies were conducted on 489 pesticide workers engaged in spraying operations on mango plantations. These workers were exposed to a variety of organochlorine and organophosphorus pesticides. A reference group consisting of 208 controls, belonging to the same socioeconomic stratum, was taken from the same area for purposes of comparison. The results of the study showed 36.5 and 41.5% prevalence of respiratory impairment in the exposed workers and in the controls, respectively. The most common pulmonary impairment among the exposed subjects (18.8%) and controls (16.9%) was of the restrictive type, followed by mixed ventilatory defect. Bronchial obstruction affected 2.5 and 3.7% of the exposed and control populations, respectively. In a comparison of the prevalence of total respiratory impairment in the pesticide workers and the controls, the nonsmokers did not show any significant difference in this study. The prevalence rate of respiratory impairment showed an increasing trend in different exposure groups (p less than 0.05), thereby clearly indicating a dose effect. The study revealed that occupational exposure to pesticides had a direct bearing on the respiratory impairment identified in the exposed workers.

This retrospective study aimed to evaluate the risks and outcome of oral anticoagulant use during pregnancy in women with prosthetic heart valves. Between December 1989 and November 1998, 192 females of childbearing age underwent heart valve replacement with a mechanical prosthesis. There were 37 pregnancies in 30 patients during follow-up. Pregnancy was terminated on medical grounds in 5 cases, there were 2 (6%) spontaneous abortions, and 1 (3%) premature birth of a normal baby who died 24 hours later due to asphyxia. The other 29 pregnancies (91%) went to full term and the mothers continued taking oral anticoagulants until a week before the expected date of delivery, then switched to heparin. There was no thromboembolism, valve thrombosis, or maternal mortality. Three babies (10%) had a skeletal deformity: nasal hypoplasia in all 3, with cleft pinna in 1. Continuation of oral anticoagulants during pregnancy provided adequate protection against thromboembolism and valve thrombosis, but the risks of fetal abnormalities and premature delivery should be explained to women of childbearing age with a mechanical valve prosthesis.

A multiple regression model considering dependent variables like vital capacity (VC), forced expiratory volume in one second (FEV1) and peak expiratory flow rate (PEFR) and age and height as independent variables for the adult male population, which includes whites of European descent and non-whites was reviewed to evaluate the role of lung function status following standardization of age and height. Non-whites showed 0.19 litre decline in VC per decade of life as compared to 0.24 litres observed in the whites of European descent. Mean VC increased 0.05 litres per centimetre in non-whites and whites. The variation in the constant term in the regression equation determined the difference between the racial groups. Like VC, FEV1 showed ethnic differences similar to those of VC. However, the magnitude of the variation in the predicted values of FEV1 was found to be less than that observed in VC. When related to VC, FEV1 showed little difference between most European populations, New Guyanaese, Indians, Negroes, Africans and Chinese because FEV1/FVC ratio had a very narrow range between 77 and 80%.

Spirometric lung functions were recorded for 109 workers (mean age 26.4 +/- 8.2 yr) occupationally exposed (mean exposure 8.9 +/- 7.7 yr) to soft wood dust in local sawmills along with 88 unexposed controls (mean age 28.7 +/- 9.9 yr) belonging to the same socioeconomic status to assess the prevalence of respiratory impairment in the exposed population. The results of the study showed a significantly higher prevalence of overall respiratory impairment in the exposed group even after standardizing for smoking habits (p less than 0.001). The adjusted rate for respiratory impairment in the exposed group was 29.4% as compared to 2.2% observed in the unexposed controls. The pattern of respiratory abnormality observed in the sawmill workers was predominantly the restrictive type (28.4%), indicating lower levels of forced vital capacity (FVC) in the exposed group; while in the control group, there were none with lung restriction The prevalence of airflow limitation, however, was similar in the exposed workers (1.8%) and controls (2.2%), thereby, indicating that bronchial obstruction was independent of wood dust exposure. It is concluded that the dust exposure in sawmills is associated mainly with restrictive type of pulmonary impairment in the exposed workers.

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