In recent years proof of “indoor air quality”, designed to protect and improve the health and safety of workers, was a central strategy in the prevention of many companies. The man creates with the environment in wh...In recent years proof of “indoor air quality”, designed to protect and improve the health and safety of workers, was a central strategy in the prevention of many companies. The man creates with the environment in which he lives and works a continuous gas exchange through breathing;this makes the respiratory system main entrance of air pollutants. The indoor pollutants are numerous and originate from different sources. Their concentration may vary over time and depends on the nature of the source, on ventilation, habits and activities carried out by the occupants in the areas concerned. It is well known that photocopiers and laser printers are equipment that emit several chemicals (ozone, solvents, toner dust) both to release the materials used for their operation (toner, ink, paper) and then to the special printing technology used. During the printing and photocopying processes occurring chemical and physical processes complex, during which the components of toner and paper will react under the influence of light and high temperatures. More recently, there have been a growing number of articles as a result of indoor air pollution. They have become more and more significant;probably because of increasing of the concentrations of harmful substances in the confined environment. Particular attention has been given to the emission of harmful substances from electronic equipment and printing that are increasingly present in living and working place. This work was the main objective the emission of volatile organic compounds, formaldehyde and ozone from laser printing devices and consequently the estimation of elimination of same substances through a paper filters which operate through a mechanism of filtration surface with interstitial and penetration of particles into matrix filter on agglomeration, they also enclose type sandwich a layer of activated carbon.展开更多
The objective of this study was to determine the concentrations of the metabolites of four selected phthalates, widely used industrial chemicals which possess endocrine-disrupting properties, in samples of amniotic fl...The objective of this study was to determine the concentrations of the metabolites of four selected phthalates, widely used industrial chemicals which possess endocrine-disrupting properties, in samples of amniotic fluid and maternal urine collected in the same day, in order to verify if the latter can be considered a measure of the fetal exposure. The quantitative determination of the metabolites was carried out by HPLC-MS/MS with isotopic dilution from 70 pregnant volunteers. Detectable concentrations of phthalates metabolites were found in amniotic fluids. As phthalate monoesters are excreted in the urine conjugated with glucuronic acid, an enzymatic hydrolysis is carried out before analysis. Amniotic fluids were tested with and without hydrolysis and only the free phthalate metabolites, not conjugated with glucuronic acid, were found. The concentration of metabolites after enzymatic hydrolysis in maternal urine is not correlated to those of amniotic fluids, but the free form concentrations are. These results suggest that only the free forms can cross the placenta. A significant number of mothers showed urine phthalate monoesters concentrations higher than non-pregnant women.展开更多
文摘In recent years proof of “indoor air quality”, designed to protect and improve the health and safety of workers, was a central strategy in the prevention of many companies. The man creates with the environment in which he lives and works a continuous gas exchange through breathing;this makes the respiratory system main entrance of air pollutants. The indoor pollutants are numerous and originate from different sources. Their concentration may vary over time and depends on the nature of the source, on ventilation, habits and activities carried out by the occupants in the areas concerned. It is well known that photocopiers and laser printers are equipment that emit several chemicals (ozone, solvents, toner dust) both to release the materials used for their operation (toner, ink, paper) and then to the special printing technology used. During the printing and photocopying processes occurring chemical and physical processes complex, during which the components of toner and paper will react under the influence of light and high temperatures. More recently, there have been a growing number of articles as a result of indoor air pollution. They have become more and more significant;probably because of increasing of the concentrations of harmful substances in the confined environment. Particular attention has been given to the emission of harmful substances from electronic equipment and printing that are increasingly present in living and working place. This work was the main objective the emission of volatile organic compounds, formaldehyde and ozone from laser printing devices and consequently the estimation of elimination of same substances through a paper filters which operate through a mechanism of filtration surface with interstitial and penetration of particles into matrix filter on agglomeration, they also enclose type sandwich a layer of activated carbon.
文摘The objective of this study was to determine the concentrations of the metabolites of four selected phthalates, widely used industrial chemicals which possess endocrine-disrupting properties, in samples of amniotic fluid and maternal urine collected in the same day, in order to verify if the latter can be considered a measure of the fetal exposure. The quantitative determination of the metabolites was carried out by HPLC-MS/MS with isotopic dilution from 70 pregnant volunteers. Detectable concentrations of phthalates metabolites were found in amniotic fluids. As phthalate monoesters are excreted in the urine conjugated with glucuronic acid, an enzymatic hydrolysis is carried out before analysis. Amniotic fluids were tested with and without hydrolysis and only the free phthalate metabolites, not conjugated with glucuronic acid, were found. The concentration of metabolites after enzymatic hydrolysis in maternal urine is not correlated to those of amniotic fluids, but the free form concentrations are. These results suggest that only the free forms can cross the placenta. A significant number of mothers showed urine phthalate monoesters concentrations higher than non-pregnant women.
