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Eleven healthy volunteers (six men, five women) and twelve cancer patients (six men, six women) were given single oral doses (2.5 mg/kg body weight) of levarnisole, an immunostimulant agent. In a second experiment eleven healthy et volunteers (six men, five women) and twelve cancer patients (six men, six women) were given single oral doses (5 rug/kg body weight) of levamisole. The levamisole concentrations in plasma (24 h blood sampling) were measured by gas chromatography after extraction. A mono-compartment open model was proposed, and some parameters were calculated. The main results from these two experiments are: the drug was absorbed well, the peak levels of levamisole in the plasma were reached after 1.0 -2.0 hrs and ranged between 0,8 l!g and 1.6 ug/ml with the 2.5 mg and 5 mg/kg body weight doses respectively (concentrations required in vitro to produce an immunological effect); the plasma half-life of levamisole calculated from the decline in the concentration curves varied between 3.3 hand 5.1 h; the absorbed fractions were 0.7 and clearance 310 ml/min; twenty-four hours after medication, the levamisole concentrations in plasma were only 6 % of the peak levels.The interindividual variability in the parameters seemed to be very important; and it may be concluded that the immunostimulant effect critically depends on the dose of the drug. A minimum effective plasma concentration is necessary to trigger its effects, on the other hand high concentrations may produce an immunosuppressive effect.

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Formaldehyde and volatile organic compounds (VOCs) are major indoor pollutants with multiple origins. Standard methods exist to measure them that require analytical expertise and provide, at best, an average value of their concentrations. There is a need to monitor them continuously during periods of several days, weeks, or even months. Recently, portable devices have become available. Two categories of portable devices are considered in this research paper: connected objects for the general public (price <500 €) and monitoring portable devices for professional users (price in the range >500 to 5000 €). The ISO method (ISO 16000-29) describes the standard for VOC detector qualification. It is quite complex and is not well adapted for a first qualitative evaluation of these low-cost devices. In this paper, we present an experimental methodology used to evaluate commercial devices that monitor formaldehyde and/or total volatile organic compounds (TVOC) under controlled conditions (23 °C, 50–65% relative humidity (RH)). We conclude that none of the connected objects dedicated to the general public can provide reliable data in the conditions tested, not even for a qualitative evaluation. For formaldehyde monitoring, we obtained some promising results with a portable device dedicated to professional users. In this paper, we illustrate, with a real test case in an office building, how this device was used for a comparative analysis.