Impact of the SARS-CoV-2 lockdown measures in Southern Spain on PM10 trace element and gaseous pollutant concentrations

Trace element concentrations within PM10, gaseous pollutants (NO2 and SO2), and PM10 levels were studied during the Covid-19 lockdown at a regional level in Southern Spain (Andalusia). Pollutant concentrations were compared considering different mobility periods (pre-lockdown, lockdown, and relaxation) in 2020 and previous years (2013–2016). An acute decrease in NO2 levels (<50%) was observed as a consequence of traffic diminution during the confinement period. Moreover, a lower reduction in PM10 levels and a non-clear pattern for SO2 levels were observed. During the lockdown period, PM10 elements released from traffic emissions (Sn and Sb) showed the highest concentration diminution in the study area. Regarding the primary industrial sites, there were no significant differences in V, Ni, La, and Cr concentration reduction during 2020 associated with industrial activity (stainless steel and oil refinery) in Algeciras Bay. Similarly, concentrations of Zn showed the same behaviour at Cordoba, indicating that the Zn-smelter activity was not affected by the lockdown. Nevertheless, stronger reductions of Cu, Zn, and As in Huelva during the confinement period indicated a decrease in the nearby Cu-smelter emissions. Brick factories in Bailen were also influenced by the confinement measures, as corroborated by the marked decrease in concentrations of Ni, V, Cu, and Zn during the lockdown compared to that from previous years. This work has shown the baseline concentrations of trace elements of PM10, which is of great value to air quality managers in order to minimise pollution levels by applying the confinement of the population, affecting both traffic and industrial anthropogenic activities.We would like to acknowledge the project of the Ministry of Science, Innovation and Universities of Spain (Project RTI2018-095937-B-I00), the co-financed project by the Andalusian Government and the EU (PY18-2332), and the Environmental Agency of Andalusia for financial and technical support. Funding for open access charge: Universidad de Huelva / CBUA

A novel application of mobile low-cost sensors for atmospheric particulate matter monitoring in open-pit mines

The authors are grateful to Atalaya Mining Company for giving the permission to carry out this research on their facilities and for their active support. Carlos Boente obtained a post-doctoral contract within the program PAIDI 2020 (Ref 707 DOC 01097) and the PY18-2332 Project, co-financed by the Junta de Andalucía (Andalusian Government), Spain and the EU. Funding for open access charge: Universidad de Huelva/CBUA, Spain

Contribution of anthropogenic and natural sources in PM10 during North African dust events in Southern Europe

The influence of North African (NAF) dust events on the air quality at the regional level (12 representative monitoring stations) in Southern Europe during a long time series (2007–2014) was studied. PM10 levels and chemical composition were separated by Atlantic (ATL) and NAF air masses. An increase in the average PM10 concentrations was observed on sampling days with NAF dust influence (42 µg m- 3 ) when compared to ATL air masses (29 µg m- 3 ). Major compounds such as crustal components and secondary inorganic compounds (SIC), as well as toxic trace elements derived from industrial emissions, also showed higher concentrations of NAF events. A source contribution analysis using positive matrix factorisation (PMF) 5.0 of the PM10 chemical data, discriminating ATL and NAF air mass origins, allowed the identification of five sources: crustal, sea salt, traffic, regional, and industrial. A higher contribution (74%) of the natural sources to PM10 concentrations was confirmed under NAF episodes compared with ATL. Furthermore, there was an increase in anthropogenic sources during these events (51%), indicating the important influence of the NAF air masses on these sources. The results of this study highlight that environmental managers should take appropriate actions to reduce local emissions during NAF events to ensure good air quality

Study of PM2.5-bound polycyclic aromatic hydrocarbons and anhydro-sugars in ambient air near two Spanish oil refineries: Covid-19 effects

We report the results from a 12 month-long study of the organic compounds associated to PM2.5 samples collected around two petroleum refineries (4 samples/month/site) in two complex industrial zones reporting atmospheric pollution issues in the past (Estuary of Huelva and Bay of Algeciras, Spain). Sampling campaign was done from March 2020 when a Covid-19 lockdown was established at Spain to March 2021. Concentrations of fine particulate polycyclic aromatic hydrocarbons (PAHs) and anhydrosugars were separately measured using gas chromatography-mass spectrometry (GC-MS) and ion chromatography-amperometric detection (IC-PAD). The annual average abundances of PM2.5-bound benzo[a]pyrene (BaP) are 0.024 and 0.013 ng˖m−3 at La Rábida and Puente Mayorga monitoring stations, while both sites have annual average concentrations of levoglucosan in PM2.5 of 14.98 and 9.78 ng˖m−3, respectively. Seasonal variations are observed for concentrations of ƩPAHs and total anhydrosugars in both sampling sites. For PAHs, the highest concentrations averaging c. a. 0.400 (La Rábida) and 0.350 ng m−3 (Puente Mayorga) are reported in cold months during December 2020-Febraury 2021 (post-lockdown period), compared to the lowest levels averaging 0.111 and 0.211 ng˖m−3, respectively, in temperate months from mid-March 2020 to early June 2020 (0.284 and 0.321 ng m−3 on average annually), coinciding with the confinement and relaxation periods in Spain. Similarly, total anhydrosugars show the highest values of 81.80 ng˖m−3 (La Rábida) and 53.52 ng˖m−3 (Puente Mayorga) in winter and lowest values of 2.71 ng˖m−3 and 3.30 ng˖m−3 into the lockdown period (22.51 and 14.09 ng˖m−3 on average annually). Except phenanthrene, PAHs are present in PM2.5 principally as result of motor vehicle exhausts. Levoglucosan, a tracer for biomass burning, peaked in December 2020 and January 2021, during the high residential wood-burning season. In addition, multivariate analysis was used to assess the origin of organic components of PM2.5 samples. The two principal components are characterized by the grouping of heavy PAHs associated to vehicular traffic, and anhydrosugars indicating biomass burning emissions, respectively.We are grateful to the project of the Ministry of Science, Innovation and Universities of Spain (Project RTI 2018-095937-B-I00), the cofinanced project by the Andalusian Government and the EU (PY18- 2332), and the Environmental Agency of Andalusia for financial and technical support. Carlos Boente obtained a post-doctoral contract within the program PAIDI 2020 (Ref 707 DOC 01097), co-financed by the Junta de Andalucía (Spain) and the EU. Funding for open access charge: Universidad de Huelva / CBUA

Physicochemical assessment of atmospheric particulate matter emissions during open-pit mining operations in a massive sulphide ore exploitation

Mining operations are critical emission sources of atmospheric particulate matter (APM). This study constitutes a physicochemical characterisation of the main geochemical anomalies associated with APM by mining operations in the renowned Riotinto Mine (Iberian Pyrite Belt, Southwest Spain). The operations studied were traffic in the mining tracks, drilling, blasting, dry and wet loading of ore/waste, and stockpiling. Chemical analysis of PM10 and PM2.5 comprised 46 potentially toxic elements (PTEs) and rare earth elements (REEs). The geochemical fingerprint of the operations in nearby populations was studied via environmental ratios after a comprehensive one-year sampling campaign at three monitoring stations. The results revealed that a notable amount of PM10 and PM2.5 is released for the mining tracks, drilling, and dry loading. Moreover, enrichments of typical elements associated with sulphide ores (e.g. Cu, Ba, Zn, As, and Pb) were found, although some of them are also present in the APM geochemical background. These results are of substantial interest to air quality managers aiming to abate the main emission sources of APM and hazardous elements associated with mining processes.Authors are grateful to Atalaya Mining Company for its permission to carry out this research on their facilities and to its active support. Carlos Boente obtained a post-doctoral contract within the program PAIDI 2020 (Ref 707 DOC 01097) and PY18-2332 Project, co-financed by the Junta de Andalucía (Andalusian Government) and the EU. Funding for open access charge: Universidad de Huelva / CBUA.Departamento de Ingeniería Minera, Mecánica, Energética y de la Construcció

PM10 Resuspension of Road Dust in Different Types of Parking Lots: Emissions, Chemical Characterisation and Ecotoxicity

The thoracic fraction of road dust (PM10) was measured for the first time in Portugal in parking areas, both outdoors and indoors, with the aim of completing existing studies carried out in active lanes of various roads. An in situ resuspension chamber was used to collect a total of 23 samples in three parking areas of Aveiro, whilst the laboratory procedures included determination of carbonaceous content (OC and EC) by a thermo-optical technique, elemental composition by ICP-MS and ICP-OES after acid digestion, and the Aliivribrio fisherii bioluminescent bacteria ecotoxicity bioassay. Dust loadings (DL10) obtained were 18.5 ± 9.8 mg PM10 m−2, in outdoor parking, and 1.8–23.7 mg PM10 m−2 for indoor parking, corresponding to emission factors of 476 and 75–589 mg veh−1 km−1, respectively. OC represented 9–30 % of PM10 for the indoor parking areas. However, for the outdoor samples, the high iron oxide content jeopardised the OC-EC separation. In those samples, carbonates accounted for 10.0 ± 3.3% of the PM10 mass. The analysis of elemental components focused on major elements (Al, Ca, Fe, K, and Mg) as well as minor elements. The total mass fraction of element oxides accounted for 27.1% (outdoor) and 23.6–34.3% (indoor). ΣPAH calculated for all parking areas accounted for 8.38–36.9 μg g−1 PM10. The ecotoxicological bioassay showed that all aqueous solutions were toxic to bioluminescent bacteria, whereas no clear correlations could be made with specific component groups, with the exception of ΣPAH and EC50.This research was funded by FEDER, through COMPETE2020–Programa Operacional Competitividade e Internacionalização (POCI), and by national funds (OE), through FCT/MCTES, through the implementation of the project “Big data to improve atmospheric emission inventories (BigAir)”, PTDC/EAM-AMB/2606/2020. Furthermore, the authors also acknowledge the financial support to CESAM (UIDB/50017/2020+UIDP/50017/2020+LA/P/0094/2020), to FCT/MCTES through national funds, and the co-funding by the FEDER, within the PT2020 Partnership Agreement and COMPETE2020. Ismael Casotti Rienda is grateful to the Portuguese Foundation of Science and Technology (FCT) for funding the scholarship SFRH/BD/144550/2019. The research work was also supported by the LIFE-REMY (LIFE20 PRE/IT/000004) and the Spanish National Research Project NEXT (PID2019-110623RB-I00), funded by MCIN/AEI/10.13039/501100011033/

Designing a low-cost wireless sensor network for particulate matter monitoring: Implementation, calibration, and field-test

Poor air quality can provoke severe impacts on health, necessitating environmental monitoring of atmospheric particulate matter (PM) to assess potential threats to human well-being. However, traditional continuous air quality monitoring systems are often costly and time-consuming in data treatment. Lately, there is a growing trend towards the use of low-cost wireless PM sensors, providing more detailed information than standard systems. This paper presents a system designed to measure air quality, specifically, a wireless sensor network composed of a distributed sensor network linked to a cloud system. The proposed system can efficiently measure air quality as it is cost-effective, small-sized, and consumes little power. Sensor nodes based on low-power long range (LoRa) motes transmit field measurement data to the cloud via a gateway, and a cloud computing system is implemented to store, monitor, process, and visualise the data. Advanced techniques were included in our cloud for data processing and analysis to optimise the detection of PM. Laboratory and field tests in the historic Riotinto mine validate the system's viability, offering real-time air quality information for nearby populations. Once calibrated, sensors demonstrate high accuracy, presenting mean error of −0.3% and low deviation (R2 = 0.96) when compared to regulatory systems for both low (<10 μgPM10/m3) and hazardous concentrations (300 μgPM10/m3), which makes them perfect as early warning systems for atmospheric pollution in mining.Funding for this research was provided by the project “68/83 Contribucion ´ de fuentes del material particulado atmosf´erico en el entorno del distrito minero de Riotinto (2023).” The authors express their appreciation to the Atalaya Mining Company for granting permission to conduct this research on their premises and for their wholehearted support. Funding for open access charge: Universidad de Huelva / CBUA, Spain.CIQSOCIQS

Source apportionment of potentially toxic PM10 near a vast metallic ore mine and health risk assessment for residents exposed

Mining is an economic activity that traditionally releases large amounts of particulate matter into the atmosphere because of the procedures required to process the mineral. In particular, polymetallic ores are environmentally harmful as they can enrich potentially toxic elements, which may cause adverse effects to humans and ecosystems due to their toxicity. The aim was to assess the impact on health of this type of mining on nearby populations. Accordingly, it was conducted an extensive PM10 sampling campaign during the entirety of 2021 through a total of 248 filters placed in three villages close to the Rio Tinto district (Southwest Spain), which is one of the largest Cu mines in the world. A total of 58 major and trace elements were analysed, along with organic carbon/elemental carbon, cations, and anions. The mean PM10 concentrations were high during spring (47 μgPM10⋅m−3) and summer (56 μgPM10⋅m−3) in the population closest to the mine, wherein values surpassed the annual and daily limit values, but were lower in the other two villages. Moreover, high enrichment of As (annual maximum mean of 6.2 ng⋅m−3), Cu (70 ng⋅m−3), Pb (19 ng⋅m−3), and Zn (50 ng⋅m−3) was observed in all locations. A positive matrix factorization (PMF) was primarily used to assess the origins of this particulate matter, revealing that the impact of the mine reduced considerably over a long distance, with contributions ranging from 36% at the mine's outskirts to 8% further away from it, which coincides with the features of the mine during the abandonment phase (2001–2015). Despite this, the risk assessment revealed that the carcinogens were within the permissible exposure limits even in the closest village, indicating a minor concern for the inhabitants from a toxicological perspective.Funding for open access charge: Universidad de Huelva / CBUA