Automated collection of real-time alerts of citizens as a useful tool to continuously monitor malodorous emissions

The evaluation of odor emissions and dispersion is a very arduous topic to face; the real-time monitoring of odor emissions, the identification of chemical components and, with proper certainty, the source of annoyance represent a challenge for stakeholders such as local authorities. The complaints of people, often not systematic and variously distributed, in general do not allow us to quantify the perceived annoyance. Experimental research has been performed to detect and evaluate olfactory annoyance, based on field testing of an innovative monitoring methodology grounded in automatic recording of citizen alerts. It has been applied in Taranto, in the south of Italy where a relevant industrial area is located, by using Odortel® for automated collection of citizen alerts. To evaluate its reliability, the collection system has been integrated with automated samplers, able to sample odorous air in real time, according to the citizen alerts of annoyance and, moreover, with meteorological data (especially the wind direction) and trends in odor marker compounds, recorded by air quality monitoring stations. The results have allowed us, for the first time, to manage annoyance complaints, test their reliability, and obtain information about the distribution and entity of the odor phenomena, such that we were able to identify, with supporting evidence, the source as an oil refinery plant

An improved method to determine PM-bound nitro-PAHs in ambient air

Nowadays, no a standard method for the determination of particulate bound nitro-PAHs (NPAHs) has been developed. Existing methods include complex sampling and extraction procedures. Moreover, their sensitivity does not allow to analyze daily PM10 samples, affecting the temporal resolution of NPAH concentrations. In this study an analytical method for the quantification of NPAHs on half 47 mm-filter samples of daily PM10 was developed and validated. NPAHs were recovered by microwave-assisted extraction, and analyzed by using a gas chromatography-triple quadrupole mass spectrometry in MRM mode. The analytical performance for 14 NPAHs (2-nitrofluorene, 9-nitroanthracene, 9-nitrophenantrene, 3-nitrophenantrene, 2-nitroanthracene, 3-nitrofluoranthene, 1-nitropyrene, 2,7-dinitrofluorene, 7-nitrobenzo[a]anthracene, 6-nitrochrysene, 1,3-dinitropyrene, 1,8-dinitropyrene, 1,6-dinitropyrene, 6-nitrobenza[a]pyrene) was investigated. Recovery extraction percentage exceeded 95% for all target compounds in the range between 0.25 and 10 ng/mL. The repeatability, expressed as Relative Standard Deviation percentage (RSD%) of five determinations, was less than 10% for target compounds except for 2,7-dinitrofluorene, 1,3- and 1,8-dinitropyrene (RSD% < 15%). The limit of detection (LOD) ranged from 12 to 84 pg/mL for most of NPAHs, except for dinitro-pyrenes and nitro-benzo(a)anthracene for which the LOD reached 1.8 ng/mL. The method developed was applied to real samples in order to evaluate the levels of NPAHs in the urban and industrial area of Taranto (South of Italy). The analysis of PM10 samples collected at four industrial and one urban sites, highlighted that in proximity of critical emission source as the biggest European steel plant and under certain weather conditions, combustion processes were the main source of NPAHs in atmosphere

Odour Detection Methods: Olfactometry and Chemical Sensors

The complexity of the odours issue arises from the sensory nature of smell. From the evolutionary point of view olfaction is one of the oldest senses, allowing for seeking food, recognizing danger or communication: human olfaction is a protective sense as it allows the detection of potential illnesses or infections by taking into account the odour pleasantness/unpleasantness. Odours are mixtures of light and small molecules that, coming in contact with various human sensory systems, also at very low concentrations in the inhaled air, are able to stimulate an anatomical response: the experienced perception is the odour. Odour assessment is a key point in some industrial production processes (i.e., food, beverages, etc.) and it is acquiring steady importance in unusual technological fields (i.e., indoor air quality); this issue mainly concerns the environmental impact of various industrial activities (i.e., tanneries, refineries, slaughterhouses, distilleries, civil and industrial wastewater treatment plants, landfills and composting plants) as sources of olfactory nuisances, the top air pollution complaint. Although the human olfactory system is still regarded as the most important and effective “analytical instrument” for odour evaluation, the demand for more objective analytical methods, along with the discovery of materials with chemo-electronic properties, has boosted the development of sensor-based machine olfaction potentially imitating the biological system. This review examines the state of the art of both human and instrumental sensing currently used for the detection of odours. The olfactometric techniques employing a panel of trained experts are discussed and the strong and weak points of odour assessment through human detection are highlighted. The main features and the working principles of modern electronic noses (E-Noses) are then described, focusing on their better performances for environmental analysis. Odour emission monitoring carried out through both the techniques is finally reviewed in order to show the complementary responses of human and instrumental sensing

Particulate Matter Toxicity Evaluation Using Bioindicators and Comet Assay

ABSTRACTAtmospheric particulate matter (PM) characterizes the atmospheric air quality. PM particles can adsorb and include several toxic air pollutants of urban areas. The current study aimed to develop an experimental procedure to assess the toxicity of the pollutants on PPM10 by means of the comet assay on earthworms directly exposed to PM10 collecting filters. A particular focus was the amount of polycyclic aromatic hydrocarbons (PAHs) in the filter, in spite of their very low concentration in PM, because of their strong mutagenic and carcinogenic effects. A quartz filter exposed to polluted air containing 24.9 mg/g of PM10 and 14.1 μg/g of PAHs was characterized and mechanically reduced into a very fine powder by means of a planetary ball mill. This powder was combined with artificial soil samples allowing treatments at 15 μg/g of PM10 (0.008 μg/g of PAHs), 22.5 μg/g of PM10 (0.012 μg/g of PAHs), 30 μg/g of PM10 (0.016 μg/g of PAHs). Earthworms were exposed to each treatment for seven days, including blank treatments with powdered clean quartz filter, such as phenanthrene (used as the standard), and an untreated soil. DNA damage was observed starting from 0.012 μg/g of PAHs in 22.5 μg/g of PM10. No single PAH was detected or quantified in the bodies of the earthworms after microwave assisted solvent extraction (MASE) and GC-MS analysis. The results demonstrate that even a very low amount of PM10 absorbed by the earthworms had a toxic effect on their immune systems, which could also have been caused by other xenobiotics included into the filter

Atmospheric particulate matter (PM) effect on the growth of Solanum lycopersicum cv. Roma plants

This study shows the direct effect of atmospheric particulate matter on plant growth. Tomato (Solanum lycopersicum L.) plants were grown for 18. d directly on PM10 collected on quartz fiber filters. Organic and elemental carbon and polycyclic aromatic hydrocarbons (PAHs) contents were analyzed on all the tested filters. The toxicity indicators (i.e., seed germination, root elongation, shoot and/or fresh root weight, chlorophyll and carotenoids content) were quantified to study the negative and/or positive effects in the plants via root uptake. Substantial differences were found in the growth of the root apparatus with respect to that of the control plants. A 17-58% decrease of primary root elongation, a large amount of secondary roots and a decrease in shoot (32%) and root (53-70%) weights were found. Quantitative analysis of the reactive oxygen species (ROS) indicated that an oxidative burst in response to abiotic stress occurred in roots directly grown on PM10, and this detrimental effect was also confirmed by the findings on the chlorophyll content and chlorophyll-to-carotenoid ratio

Improving recognition of odors in a waste management plant by using electronic noses with different technologies, gas chromatography\u2013mass spectrometry/olfactometry and dynamic olfactometry

Odor emissions from waste management plants have long been an environmental and economic issue, but only recently regional authorities in Italy are regulating this sector by imposing control and mitigation of the phenomenon. Electronic noses, initially developed as cheap, easy tools to detect volatiles, may have the required time-resolved coverage of the odor emission phenomenon in a cheap and feasible way with respect to chemical analysis of air. One crucial issue to resolve is to evaluate the discriminant capacity of a sensor array in-field and under working conditions. In this paper the authors have studied the responses of electronic noses of different technologies to odors emitted from a waste management plant, by integrating results obtained with dynamic olfactometry and gas chromatography\u2013mass spectrometry/olfactometry, in the aim to implement a monitoring system and improve cleaner production technologies. Three most impacting odor sources in the waste management plant were detected: biogas, a by-product of mechanical treatment of municipal solid wastes, with low organic fraction and a sludge pressed and dehydrated from treatment of urban wastewater. The most odor impacting source was the sludge and the major responsible of the odor impacts were aromatics (in particular 1,3,5-trimethyl benzene), aliphatic hydrocarbons, terpenes and sulphur volatiles (methyl disulphide, carbon disulphide, dimethyltrisulphide). Ten Metal Oxide Semiconductors and 32 polymer/black carbon (Nano Composite Array) sensors in two electronic noses, were tested for discrimination source capabilities. Results of linear discriminant analysis and cross validation give 86.7% successful recognition for Metal Oxide Semiconductors, 53.3% for Nano Composite Array and 93.3% for a selection of sensors belonging to both technologies chosen according to the selectivity towards the odor active molecules. The containment of odors could also be achieved by spraying a specific product and monitoring the process using selected sensors of the arrays. The results of the in-field work demonstrate strengths and weaknesses of different construction technologies in the e-noses arrays, to characterize and monitor in-site and in real time odor emissions from waste management plants

Assessment of Impacts Produced by Anthropogenic Sources in a Little City near an Important Industrial Area (Modugno, Southern Italy)

An annual monitoring campaign of VOCs, consisting of twelve sampling periods, was carried out from June 2008 to June 2009 in Modugno, a city located in the Apulia region (Southern Italy), in order to assess the urban air quality, identify the main emission sources, and quantify the cancer and no-cancer risk attributable to inhalation exposures. Monitoring, carried out by using the Radiello diffusive samplers, was conducted in eleven sampling sites throughout the city taking into account the traffic density and the architecture of the city. From the study of the data, it was found that, among all considered VOCs, benzene, toluene, ethylbenzene, and xylenes (BTEX) are the pollutants at higher concentration. The analysis of VOC concentrations, the study of the topography of the city, and the use of different diagnostic ratios between the BTEX species showed that the vehicular traffic emissions were the predominant source of VOCs in the urban area of Modugno. Despite that the annual concentration of benzene is lower than the regulatory limit, the estimation of cancer risk showed that the global lifetime cancer risk attributed to the investigated VOC exposure was not negligible and therefore should be taken into account in future regulatory approaches