Development and calibration of an integrative passive sampler for monitoring VCM in drinking water networks

This paper evaluates the applicability of a new sampling device for monitoring vinyl chloride monomer (VCM) in drinking water networks. This system consists of an adsorbing cartridge filled with a strong adsorbent enclosed between two sheets of polyethylene-polyamide membrane. The passive sampler (PS) combines preconcentration on the cartridge with easy extraction by thermal desorption into a gas chromatograph (GC), coupled with a tandem mass spectrometer (MS/MS). In order to estimate the suitability of the device for this application, samplers were calibrated in a hydraulic pilot under controlled parameters. The influences of temperature, flow velocity and variation of concentration of exposure were then examined. Linear uptake was observed during a VCM exposure of 12 days and the effect of temperature on the sampling rate was evaluated. This sampling device responds to an aquatic environmental contamination and Public Health issue, both by the organic volatile contaminant monitored in this environment, and by the sampling approach, still little used in drinking water networks. It offers a complementary monitoring to the current technique, providing a more representative assessment of the temporal contamination.

Personal Passive Air Samplers for Chlorinated Gases Generated from the Use of Consumer Products

Various chlorine-based disinfectants are being used during the COVID-19 pandemic; however, only a few studies on exposure to harmful gases resulting from the use of these disinfectants exist. Previously, we developed a personal passive air sampler (PPAS) to estimate the exposure level to chlorine gas while using chlorinated disinfectants. Herein, we investigated the color development of the passive sampler corresponding to chlorine exposure concentration and time, which allows the general population to easily estimate their gas exposure levels. The uptake and reaction rate of PPAS are also explained, and the maximum capacity of the sampler was determined as 1.8 mol of chlorine per unit volume (m3) of the passive sampler. Additionally, the effects of disinfectant types on the gas exposure level were successfully assessed using passive samplers deployed in a closed chamber. It is noteworthy that the same level of chlorine gas is generated from liquid household bleach regardless of dilution ratios, and we confirmed that the chlorine gas can diffuse out from a gel-type disinfectant. Considering that this PPAS reflects reactive gas removal, individual working patterns, and environmental conditions, this sampler can be successfully used to estimate personal exposure levels of chlorinated gases generated from disinfectants.

Feasibility Study of 3D Printed Materials for an Ammonia Emission Passive Sampler

Ammonia (NH3) emission accounts for a loss of 10 to 60% of the total nitrogen input in rice fields. NH3 in the air reacts with sulphuric acid, nitric acid and hydrochloric acid to form ammonium salt, which increases the concentration of PM2.5 particles in the atmosphere. These fine particles can cause respiratory problems. A reliable NH3 sampler is important in order to quantify the NH3 emission. The objective of this study is to evaluate the suitability of three 3D printed materials, namely acrylonitrile-butadiene-styrene (ABS), polylactic acid (PLA) and polypropylene (PP) compared to stainless steel and glass, as the interior material of an NH3 passive sampler for use with the chemical-trap approach; Stainless steel and glass are typically used for construction of the NH3 passive sampler. The sample plates were coated with acetone with 3% oxalic acid and tested in closed static chambers with three different NH3 sources. ABS, PP and PLA tolerated the acetone solution with PP being the least reactive. However, PP heavily warped during 3D-printing resulting in a deformed shape. Performance of coated ABS plates in trapping NH3 is similar to stainless steel and glass plates.