Objectives: Work in sewage treatment plants may cause health problems in terms of airways symptoms, unusual tiredness, fever, and diarrhoea. The presence of such symptoms has been related to bacterial endotoxin. The p...Objectives: Work in sewage treatment plants may cause health problems in terms of airways symptoms, unusual tiredness, fever, and diarrhoea. The presence of such symptoms has been related to bacterial endotoxin. The project was undertaken to assess if risk evaluations could be performed by measuring the amounts of two different microbial enzymes and to evaluate their relation to endotoxin. Methods: Measurements were performed at 120 work sites in 10 different sewage treatment plants of varying age and capacity. The content of N-acetyl-hexosaminidase (NAHA), bacterial hydrolase (BH) and endotoxin was measured in sewage water and in airborne samples. Results: There was a close relationship between endotoxin and NAHA, both in the water itself and in air samples. Generally exposure levels were low but higher at work sites where the water or sludge was agitated or when repairing pumps and cleaning basins. Conclusions: Measurements of NAHA are suitable to determine risk exposures in sewage treatment plants. Such measurements are faster and cheaper than measures of endotoxin. A level of 50-70 U/m3 is suggested as a risk threshold. Further work is required to define more precise threshold limit values.展开更多
Hypothesis: Although mineral deficiency in particular magnesium is a known risk factor for cardiovascular disease intervention experiments with magnesium show only modest results. Previously published data suggest tha...Hypothesis: Although mineral deficiency in particular magnesium is a known risk factor for cardiovascular disease intervention experiments with magnesium show only modest results. Previously published data suggest that there may be particular risk groups in the population. The study was undertaken to investigate if such risk groups could be identified. Experimental design: Subjects (n = 31) were 50 - 79 years old with no disease. The 24 hour urinary excretion of urea (proxy for acidity), magnesium, calcium, and potassium was measured at two week intervals, with and without intervention with mineral water. Intervention with mineral water comprised 75 mL daily, supplying 3.1 mmol Mg, 2.3 Ca, and 0.02 K. Major results: There was a significant relation between acidity and excretion of magnesium, calcium, and potassium, both at one occasion and regarding changes over time. Among subjects with a high secretion of urea there was an inverse relation between the excretion of magnesium and systolic blood pressure. After intervention with mineral water, there was a strong tendency to a decrease in the systolic blood pressure among those with an initial high excretion of urea and a low excretion of magnesium. Conclusions: The results demonstrate the importance of acid-base conditions for mineral homeostasis and suggest the presence of risk groups in the population, related either to a low intake or to a disorder in the reabsorbtion mechanisms. Mineral water decreased the systolic blood pressure in that particular risk group.展开更多
文摘Objectives: Work in sewage treatment plants may cause health problems in terms of airways symptoms, unusual tiredness, fever, and diarrhoea. The presence of such symptoms has been related to bacterial endotoxin. The project was undertaken to assess if risk evaluations could be performed by measuring the amounts of two different microbial enzymes and to evaluate their relation to endotoxin. Methods: Measurements were performed at 120 work sites in 10 different sewage treatment plants of varying age and capacity. The content of N-acetyl-hexosaminidase (NAHA), bacterial hydrolase (BH) and endotoxin was measured in sewage water and in airborne samples. Results: There was a close relationship between endotoxin and NAHA, both in the water itself and in air samples. Generally exposure levels were low but higher at work sites where the water or sludge was agitated or when repairing pumps and cleaning basins. Conclusions: Measurements of NAHA are suitable to determine risk exposures in sewage treatment plants. Such measurements are faster and cheaper than measures of endotoxin. A level of 50-70 U/m3 is suggested as a risk threshold. Further work is required to define more precise threshold limit values.
文摘Hypothesis: Although mineral deficiency in particular magnesium is a known risk factor for cardiovascular disease intervention experiments with magnesium show only modest results. Previously published data suggest that there may be particular risk groups in the population. The study was undertaken to investigate if such risk groups could be identified. Experimental design: Subjects (n = 31) were 50 - 79 years old with no disease. The 24 hour urinary excretion of urea (proxy for acidity), magnesium, calcium, and potassium was measured at two week intervals, with and without intervention with mineral water. Intervention with mineral water comprised 75 mL daily, supplying 3.1 mmol Mg, 2.3 Ca, and 0.02 K. Major results: There was a significant relation between acidity and excretion of magnesium, calcium, and potassium, both at one occasion and regarding changes over time. Among subjects with a high secretion of urea there was an inverse relation between the excretion of magnesium and systolic blood pressure. After intervention with mineral water, there was a strong tendency to a decrease in the systolic blood pressure among those with an initial high excretion of urea and a low excretion of magnesium. Conclusions: The results demonstrate the importance of acid-base conditions for mineral homeostasis and suggest the presence of risk groups in the population, related either to a low intake or to a disorder in the reabsorbtion mechanisms. Mineral water decreased the systolic blood pressure in that particular risk group.
