Nasal or oral oil application on infants: a possible risk factor for adult bronchiectasis.

Lipid pneumonia has been observed in infants exposed by inhalation of oil or butter applied into the nose or throat as part of an old custom. We performed a case-control study to test the hypothesis, that this ancient tradition may be a predisposing factor to bronchiectasis. A case group of 59 patients with bronchiectasis and three control groups -46 patients with COPD, 32 asthmatics, and 71 healthy Saudis-were questioned about possible risk factors of bronchiectasis including nasal or oral application of oil/butter at infancy. The risk of witnessed exposure to this old folk remedy was significantly higher among the cases than the controls (OR = 3.9 (1.7-8.8), (95% confidence interval) p < 0.001). Application of oil or butter into the nasal or oral cavity of infants may be a risk factor for bronchiectasis.

Effect of theophylline and salbutamol on hepatic drug metabolism.

Fifteen otherwise healthy asthmatics with reversible airway obstruction were treated with salbutamol (8 mg slow release twice daily) and theophylline (300 mg twice daily). Each drug was administered for 4 weeks in a double-blind randomized crossover trial. Irrespective of which drug was given first, salbutamol increased antipyrine clearance significantly by a factor of 1.10 and 1.15 after 2 and 4 weeks of treatment, respectively. Theophylline did not change antipyrine clearance. There was no correlation between the extent of change in antipyrine clearance during either of the drug treatments and alterations in lung function as assessed by changes in peak flow, forced vital capacity and forced expiratory volume in first second.

Metronidazole clearance: a one-sample method and influencing factors.

After 96 administrations of metronidazole to 36 subjects, it was found that the clearance could be determined from one plasma sample, the dose, and a volume of distribution estimated from sex, age, body weight, and height, without loss of precision and accuracy compared with conventional clearance determinations (r greater than 0.97). In 230 sample pairs the plasma and saliva concentrations of metronidazole were identical (r = 0.99). In 119 subjects the one-sample clearance of metronidazole was unimodally distributed. Body weight (r = 0.28) and the alcohol consumption (r = 0.23) correlated with the metronidazole clearance. In the same subjects the consumption of tobacco (r = 0.28), alcohol (r = -0.19), coffee/tea (r = 0.27), age (r = -0.24), and sex (r = 0.28) correlated with the antipyrine clearance. The clearances of metronidazole and antipyrine were correlated (r = 0.34). The differential influence of the environmental factors on the elimination rates supports differential metabolism of metronidazole and antipyrine.

Antipyrine and metronidazole metabolism during occupational exposure to gasoline.

Antipyrine and metronidazole clearance was measured in 18 fuel-filling attendants by the single-sample method while the attendants were being exposed occupationally to gasoline; the measurements were repeated after 2-4 weeks with no exposure. Eighteen office workers were investigated simultaneously. The median concentration of gasoline in the breathing zone of the fuel-filling attendants during filling and cleaning operations was 270 mgm-3 (range 18-1758 mgm-3). Antipyrine clearance was 18% higher during exposure to gasoline than after 2-4 weeks of vacation (P less than 0.01), while antipyrine clearance was unchanged in the office workers. No change was found in metronidazole clearance in either group. Antipyrine clearance was on average 26% higher in the smokers than in the nonsmokers (P less than 0.05), while metronidazole clearance was similar in smokers and nonsmokers. We conclude that gasoline is an inducer of antipyrine elimination, with no impact on metronidazole elimination. This indicates that gasoline has a differential inducing effect on the hepatic drug metabolizing enzymes of man.

Jet fuel and liver function.

The impact of occupational exposure to jet fuel on antipyrine elimination was studied in 91 fuel-filing attendants. The mean antipyrine clearance was enhanced to 68.4 (SD 19.5) ml/min during exposure to jet fuel compared to 57.9 (SD 18.1) ml/min after an exposure-free period of two to four weeks. The corresponding values for 47 office workers (referents) were 62.7 (SD 22.2) ml/min and 56.4 (SD 22.3) ml/min. The median jet fuel concentration in the breathing zone of the fuel-filling attendants was 31 (range 1-1 020) mg/m3. No known inducing factor could be identified in the work environment of the office workers. No difference in the concentration of aspartate aminotransferase and alkaline phosphatase in serum was found either within or between the groups. Our study indicates that jet fuel, which is a mixture of aliphatic and aromatic organic solvents resembling gasoline and white spirit, is an inducer of hepatic drug metabolism in man.

Chelatable lead body burden (by calcium-disodium EDTA) and blood lead concentration in man.

The cheletable part of lead body burden was measured in 32 workers and seven office workers after an infusion test with CaNa2EDTA. The workers had been exposed to lead at a lead and zinc processing unit for one to three years (mean one year). There was good correlation (r = 0.87) between blood lead and chelatable urinary lead excretion described by the equation y = 0.07 . 10(0.46.x). From this equation it can be predicted that the generally accepted limit value for chelatable urinary lead excretion, 0.42 mumol/mmol CaNa2EDTA administered per 24 hours (3.1 mumol/24 hours or 650 micrograms/24 hours), corresponds to a blood lead concentration (PbB) of 1.7 mumol/l (or 35 micrograms/100 ml), which is lower than the commonly accepted limit value of 2.9 mumol/l (or 60 micrograms/100 ml) for occupationally lead-exposed persons. There was a better correlation between the cheletable lead excretion and the urinary ALA-excretion (r = 0.45; p less than 0.001) than between PbB and the urinary ALA-excretion (r = 0.26; p greater than 0.05).