Occupational Exposure and Environmental Release: The Case Study of Pouring TiO2 and Filler Materials for Paint Production.

Pulmonary exposure to micro- and nanoscaled particles has been widely linked to adverse health effects and high concentrations of respirable particles are expected to occur within and around many industrial settings. In this study, a field-measurement campaign was performed at an industrial manufacturer, during the production of paints. Spatial and personal measurements were conducted and results were used to estimate the mass flows in the facility and the airborne particle release to the outdoor environment. Airborne particle number concentration (1 × 103-1.0 × 104 cm-3), respirable mass (0.06-0.6 mg m-3), and PM10 (0.3-6.5 mg m-3) were measured during pouring activities. In overall; emissions from pouring activities were found to be dominated by coarser particles >300 nm. Even though the raw materials were not identified as nanomaterials by the manufacturers, handling of TiO2 and clays resulted in release of nanometric particles to both workplace air and outdoor environment, which was confirmed by TEM analysis of indoor and stack emission samples. During the measurement period, none of the existing exposure limits in force were exceeded. Particle release to the outdoor environment varied from 6 to 20 g ton-1 at concentrations between 0.6 and 9.7 mg m-3 of total suspended dust depending on the powder. The estimated release of TiO2 to outdoors was 0.9 kg per year. Particle release to the environment is not expected to cause any major impact due to atmospheric dilution.

Organic aerosol molecular composition and gas-particle partitioning coefficients at a Mediterranean site (Corsica).

Molecular speciation of atmospheric organic matter was investigated during a short summer field campaign performed in a citrus fruit field in northern Corsica (June 2011). Aimed at assessing the performance on the field of newly developed analytical protocols, this work focuses on the molecular composition of both gas and particulate phases and provides an insight into partitioning behavior of the semi-volatile oxygenated fraction. Limonene ozonolysis tracers were specifically searched for, according to gas chromatography-mass spectrometry (GC-MS) data previously recorded for smog chamber experiments. A screening of other oxygenated species present in the field atmosphere was also performed. About sixty polar molecules were positively or tentatively identified in gas and/or particle phases. These molecules comprise a wide range of branched and linear, mono and di-carbonyls (C3-C7), mono and di-carboxylic acids (C3-C18), and compounds bearing up to three functionalities. Among these compounds, some can be specifically attributed to limonene oxidation and others can be related to α- or ß-pinene oxidation. This provides an original snapshot of the organic matter composition at a Mediterranean site in summer. Furthermore, for compounds identified and quantified in both gaseous and particulate phases, an experimental gas/particle partitioning coefficient was determined. Several volatile products, which are not expected in the particulate phase assuming thermodynamic equilibrium, were nonetheless present in significant concentrations. Hypotheses are proposed to explain these observations, such as the possible aerosol viscosity that could hinder the theoretical equilibrium to be rapidly reached.

Multi-tool formaldehyde measurement in simulated and real atmospheres for indoor air survey and concentration change monitoring.

Formaldehyde is of particular health concern since it is carcinogenic for human and ubiquitous in indoor air where people spend most of their time. Therefore, it is important to have suitable methods and techniques to measure its content in indoor air. In the present work, four different techniques have been tested in the INERIS exposure chamber and in indoor environments in comparison to a standard active method: passive sampling method based on the reaction of 2,4-dinitrophenylhydrazine with formaldehyde, two on-line continuous monitoring systems based on fluorescence and UV measurements and a portable commercialised analyser based on electrochemical titration. Two formaldehyde concentrations, about 10 and 25 µg m(-3) were generated in an exposure chamber under controlled conditions of temperature, relative humidity, and wind speed to simulate real conditions and assess potential influence on passive sampling and continuous systems response. Influence of sampling periods on passive sampling has also been evaluated. The real atmosphere experiments have been performed in four different indoor environments: an office, a furniture shop, a shopping mall, and residential dwellings in which several potential formaldehyde sources linked to household activities have been tested. The analytical and sampling problems associated with each measurement method have been identified and discussed. An overall agreement between each technique has been observed and continuous analyzers allowed for formaldehyde concentrations change monitoring and secondary formation of that pollutant observation.