Microbial volatile organic compounds as indicators of fungi. Can an electronic nose detect fungi in indoor environments?

peer reviewedThe paper presents a review of several studies on the detection of microbial volatile organic compounds (MVOCs) considered as indicators of fungal contamination. As fungi produce specific profiles, or fingerprints of volatile compounds, the electronic nose technology is a very promising opportunity for rapid and non costly detection of fungi in buildings. E-noses are able to distinguish between mouldy and non-mouldy samples, and also to recognise certain species of fungi. However, two limiting factors may appear decisive for employment of electronic noses in indoor fungi detection: low concentrations of MVOCs and presence of interfering substances in indoor environments

Use of specific in-situ sensors : enose

e-nose principle explanationomniscienti

Interests of automatic odour sampling devices, illustration with a wallonia study

From November 2018 to September 2019, two Odorprep samplers were tested in an industrial valley and a solid waste treatment plan in Wallonia (Belgium) . The experiments were organized in collaboration with the Scientific Institute of Public Service of Wallonia (ISSeP). Local authorities were also involved: they were in charge of activating the sampling devices when the smell was perceived and had to complete the questionnaires, which included the description of the odour characteristic

Capteur à oxide métallique commercial pour l'analyse d'haleine sensible aux vapeurs d'alcane à longue chaine

peer reviewedWithin an ongoing European project on breath analysis by IOMS, sensitivity of sensors to various VOCs is studied, as breath VOCs are considered as lung cancer biomarkers. Sensitivities of several commercial metal oxide sensors to various VOC have been studied. It was found that two sensors reacted to decane presence. This is an unusual property for metal oxide gas sensors. This paper shows obtained results and details the methodology employed to obtain them.Pathaco

Odour sampling system with remote triggering: feedback from a Belgian experience

An automatic odour sampling system can be activated remotely to collect samples when an odour event is perceived. Activation of sampling can be done by a neighbour when he smells an odour but also by an environmental agency, a laboratory or local authorities. Another approach is instrumental triggering for instance by a chemical analyser, an instrumental odour monitoring system (e-nose) or even simply by a wind vane. Remote odour sampling is particularly useful in ambient air at the receptor site and at the fenceline when emissions and perceptions are not continuous. It is ideal for cases of short exposition time and low frequency. Indeed, in most cases, the service in charge of the odour sampling is not close enough to arrive during the odour event and collect/measure the odour during a complaint in order to “objective” it [1]. If there is a temperature system conditioning, it allows for sampling at any time of the day and the night while maintaining a good preservation of the odour in the bags (among others preventing condensation). Complementary sampling/measurement materials like adsorbent tubes and low cost gas sensors can be activated at the same time as the odour bag sampling. Odour correlation with chemicals is then possible. The study in Belgium was performed with the collaboration of the local authorities: they were in charge of activating the sampling devices located in the close proximity of industrial areas. Two samplers (Odorprep®) were installed in a Wallonia industrial valley, where odour complaints were usual. The campaign had lasted from November 2018 to September 2019. Two trailers, from ISSeP, equipped with air quality analyzers, measured half-hourly NH3, H2S, BTEX, limonene and pinene. A meteorological weather station measured wind direction and speed, T, RH and pressure. Olfactometric analyses were performed by ULiège SAM laboratory with a TO Evolution 6FC according to EN 13725. One aim was to use the odour concentrations measured at the receptor level in order to estimate an odour emission rate [2]. Odour dispersion modelling is performed with ADMS 5 software (CERC). A second goal was to study potential correlation of the odour event and some chemical compounds. The results (odour concentration, chemicals concentration, dispersion model results, weather conditions) will be presented as well as the assessment of strengths and weaknesses of the automatic sampling system

Establishing an Air Quality Index Based on Proxy Data for Urban Planning Part 1: Methodological Developments and Preliminary Tests

peer reviewedIn the last few decades, urban planning has expanded regarding environmental considerations. However, air quality, which is regarded as an important aspect of the green development of cities, is not considered in urban planning. This research aims to propose a tool to easily introduce air quality considerations into urban projects. Nowadays, the usual air pollutants (NOx, PM, SO2, and O3) are measured via sophisticated monitoring stations—or even low-cost devices—to give near-real-time air quality indices. However, stations are not adapted to local air pollution and real-time data are not helpful for planning purposes. An index able to rank areas and projects based on urban “air proxy data” would help decision makers. This paper presents how to create an air quality index as a decision support tool for urban planning. No pollutant measurement campaign will be necessary and only data that are easily accessible, even to nonexperts, are used. This paper describes the methodological development of an index that we call AQOI (Air Quality Observed Index), and the results obtained for four different locations (industrial, urban, and rural) considered as preliminary tests.EcoCityTool

Commercial metal oxide sensor sensitive to higher alkane

peer reviewedWithin an ongoing European project on breath analysis by IOMS, sensitivity of sensors to various VOCs is studied, as breath VOCs are considered as lung cancer biomarkers. Sensitivities of several commercial metal oxide sensors to various VOC have been studied. It was found that two sensors reacted to decane presence. This is an unusual property for metal oxide gas sensors. This paper shows obtained results and details the methodology employed to obtain them.Pathaco

Présentation du développement méthodologique d’un nouvel indicateur de la qualité de l’air en zone urbaine – AQOI – Air Quality Observed Index

peer reviewedA la croisée des rénovations des centres urbains et des performances environnementales, il est parfois difficile pour les autorités locales de maintenir un budget financier et temporel de l’ordre du raisonnable. Actuellement, les rénovations urbaines ne tiennent pas compte de la qualité de l’air du site et de l’impact que pourrait avoir une éventuelle transformation de celui-ci. En effet, il n’existe pas d’indicateur, de faible coût, exprimant la qualité de l’air à une échelle locale. Les solutions proposées actuellement sont soit de la modélisation de la pollution atmosphérique, soit des campagnes de mesure, celles-ci étant symbole de consommation de temps et d’argent. C’est de ce constat qu’un projet de thèse a émergé au sein du labo SAM. L’idée est de développer un indicateur exprimant un état général de la qualité de l’air d’un site sans passer par des mesures de concentration de polluants gazeux. Il doit offrir la possibilité de choisir le meilleur site pour un projet d’un point de vue de la qualité de l’air rien qu’en implémentant celui-ci dans un Système d’Information Géographique (SIG). De plus, il doit permettre aux décideurs de sélectionner le meilleur projet de rénovation d’un site ayant le moindre impact sur la qualité de l’air. Le développement de cet indicateur a débuté dans le projet de recherche EcoCityTools (Projet financé par la région Wallonne) pour des sites wallons. L’indicateur est alimenté par des données disponibles gratuitement sur Internet et visualisables sur SIG. AQOI (Air Quality Observed Index) est calculable pour une superficie maximale de 90 000m², soit une dimension de maille de 300mx300m. La thèse est actuellement à l’étape de validation de l’outil (sur la Wallonie mais également sur Bordeaux Métropole). La méthodologie de construction de cet indicateur est présentée ainsi que les variables le constituant