Modeling the impact of heat stress on the toxicokinetics of toluene and acetone.

Many workers can be exposed simultaneously to heat and volatile chemicals. In a controlled human exposure study, it was observed that an increase in ambient temperature was associated with increased blood concentrations for acetone and toluene. Based on the expected changes in physiological parameters that occur with an increase in ambient temperature, we aimed to develop a PBPK model for acetone and toluene that could account for the impact of temperature on the kinetics of these solvents.

Impact of improved indoor air quality in Nunavik homes on children's respiratory health.

Between 2007 and 2012, hospitalization rate related to respiratory system diseases in children ≤1-year-old was near 7 times higher in Nunavik compared with the whole province of Quebec. To assess the impact of poor indoor air quality (IAQ) in residential environments on children's respiratory health, the Nunavik's intervention study investigated the impact of the optimization of ventilation systems on the incidence rates of respiratory infections in children in Nunavik. Children under 10 years were recruited and categorized according to the type of ventilation system in their home: energy recovery ventilator (ERV), heat recovery ventilator (HRV), no HRV or ERV, and control groups.

Impact of heat on biological concentrations of toluene and acetone resulting from exposure by inhalation: A pilot study.

Climatic conditions raise new concerns about the potential impact of heat on the absorption and kinetics of certain chemicals. The impact of 3 temperatures (21, 25 and 30 °C WBGT) on the toxicokinetics of toluene and acetone was therefore evaluated in five human subjects during controlled exposures in an inhalation chamber. Biological samples were collected and analyzed by GC-MS/MS.

Cardiopulmonary values and organ blood flows before and during heat stress: data in nine subjects at rest in the upright position.

Physiological changes associated with thermoregulation can influence the kinetics of chemicals in the human body such as alveolar ventilation (VA) and redistribution of blood flow to organs. In this study, the influence of heat stress on various physiological parameters was evaluated in nine male volunteers during sessions of exposure to wet-bulb globe temperatures (WBGT) of 21, 25, and 30 °C for 4 h. Skin and core temperatures and more than 20 cardiopulmonary parameters were measured.

Evaluation and modeling of the impact of coexposures to VOC mixtures on urinary biomarkers.

Context: Urinary biomarkers are widely used among biomonitoring studies because of their ease of collection and nonintrusiveness. Chloroform and TEX (i.e.

A method for quantification of volatile organic compounds in blood by SPME-GC-MS/MS with broader application: From non-occupational exposure population to exposure studies.

Humans are continuously exposed to volatile organic compounds (VOCs) as these chemicals are ubiquitously present in most indoor and outdoor environments. In order to assess recent exposure to VOCs for population-based studies, VOCs are measured in the blood of participants. This work describes an improved method to detect 12 VOCs by head-space solid-phase microextraction gas chromatography coupled with isotope-dilution mass spectrometry in selected reaction monitoring mode (SPME-GC-MS/MS).

Comparison of photoacclimation in twelve freshwater photoautotrophs (chlorophyte, bacillaryophyte, cryptophyte and cyanophyte) isolated from a natural community.

Different representative of algae and cyanobacteria were isolated from a freshwater habitat and cultivated in laboratory to compare their photoacclimation capacity when exposed to a wide range of light intensity and to understand if this factor may modify natural community dominance. All species successfully acclimated to all light intensities and the response of phytoplankton to increased light intensity was similar and included a decrease of most photosynthetic pigments accompanied by an increase in photoprotective pigment content relative to Chl a. Most species also decreased their light absorption efficiency on a biovolume basis.