The dynamic method of generating reference Volatile Organic Compounds (VOC) mixtures at trace level requires the uninterrupted blending of the component flows. The accurate control of the dilution air flows can be realized by Mass Flow Controllers (MFC). Accuracy and stability of MFC are here measured and discussed in order to verify their use in dynamic gas dilutors. Long term stability confir...

Studies of unexplained symptoms observed in chemically sensitive subjects have increased the awareness of the relationship between neurological and immunological diseases due to exposure to volatile organic compounds (VOCs). However, there is no direct evidence that links exposure to low doses of VOCs and neurological and immunological dysfunction. We review animal model data to clarify the rol...

Malodorous emissions and potentially pathogenic microorganisms which develop during domestic organic waste collection are not only a nuisance but may also pose health risks. The aim of the present study was to determine whether the presence of specific microorganisms in biowastes is directly related to the composition of the emitted volatile organic compounds (VOCs). The succession of microbial...

Foul condensates from the digesters and evaporators contain reduced sulfur gas and organic compounds, such as methanol (MeOH) and turpentine, which contribute greatly to pulp mill water pollution in the form of Biochemical Oxygen Demand (BOD) and toxicity, and air pollution in the form of Volatile Organic Compounds (VOC), and odor. For this reason, foul condensates are collected and treated by ...

The analysis and forecast of elevated boundary layer ozone is of particular concern since it is known to have adverse effects on health, vegetation and material. The main contributors to the formation of photochemical smog, and high ozone levels are the emissions of Volatile Organic Compounds (VOC) and NOx. There is a complex relationship between VOC and NOx leading to ozone generation, which v...

Volatile organic compounds (VOCs) in exhaled human breath can serve as potential disease-specific and exposure biomarkers and therefore can reveal information about a subject's health and environment. Pyridine, a VOC marker for exposure to tobacco smoke, and isoprene, a liver disease biomarker, were studied using atmospheric pressure chemical ionization mass spectrometry (APCI-MS). While both m...

Concentrations of halogenated volatile organic compounds VOCs were determined by gas chromatography GC with an electron-capture detector GC-ECD and by gas chromatography with mass spectrometry GC-MS in 109 groundwater samples from five study areas in the United States. In each case, the untreated water sample was used for drinking-water purposes or was from a monitoring well in an area near a d...

INTRODUCTION Tobacco smoke is a source of free radicals and reactive oxygen and nitrogen species, which are the main causes of oxidative stress. The analysis of volatile organic compounds (VOC) in exhaled breath is an indirect method of measuring the level of oxidative stress that occurs in the airways caused by tobacco consumption. The aim of this study was to determine whether smoking influen...

While various volatile organic compounds (VOCs) are known to show neurotoxic effects, the detailed mechanisms of the action of VOCs on the autonomic nervous system are not fully understood, partially because objective and quantitative measures to indicate neural abnormalities are still under development. Nevertheless, heart rate variability (HRV) has been recently proposed as an indicative meas...