A new sorbent tube for atmospheric NOx determination by active sampling

Sulphurous air pollutants and exposure events of workers in thermal-mineral springs: a case study of Contursi Terme (Salerno, Italy)

Thermo-mineral springs are widely spread over the volcanic areas of Salerno, a city in southern Italy. Although the water of thermal structures provides beneficial effects on human health, the air is characterized by the presence of potentially toxic compounds, such as hydrogen sulphide (H₂S) and sulphur dioxide (SO₂). Exposure to sulphurous compounds may have detrimental effects on human health, with asthma being the most common. In this study, air concentrations of H₂S and SO₂ in the thermal springs of Contursi Terme (Salerno, Italy) were monitored for 4 months (using both active and passive sampling), along with the chemical and microclimatic characterization of thermal water, to assess workers' exposure to these pollutants. An in-depth characterization of indoor air at the springs is paramount to establish emission control limits for occupational exposure and to take protective measures. The air concentration of SO₂ varied from 0.11 ± 0.02 to 0.91 ± 0.02 mg/m³, following a seasonal pattern (higher values in winter and lower in spring). Conversely, indoor H₂S concentrations did not vary significantly with time, but outdoor levels (from 0.40 ± 0.03 to 1.90 ± 0.03 mg/m³) were always higher than indoor ones (from 0.11 ± 0.03 to 0.56 ± 0.03 mg/m³). Not negligible air concentrations of these pollutants were detected in this thermal spring workplace, so further investigations are needed to ensure workers' safety.

Investigations on historical monuments' deterioration through chemical and isotopic analyses: an Italian case study

In this paper, we analysed the efflorescences present in the frescos of a monumental complex named S. Pietro a Corte situated in the historic centre of Salerno (Campania, Italy). The groundwater of the historic centre is fed by two important streams (the Rafastia and the Fusandola) that can be the sources of water penetration. The aims of this work are to (i) identify the stream that reaches the ancient frigidarium of S. Pietro a Corte and (ii) characterize the efflorescences on damaged frescos in terms of chemical nature and sources. In order to accomplish the first aim, the water of the Rafastia river (7 samples) and the water of the Fusandola river (7 samples) were analysed and compared with the water of a well of the Church (7 samples). The ionic chromatography measurements on the water samples allowed us to identify the Rafastia as the river that feeds the ancient frigidarium of S. Pietro a Corte. To investigate the nature and the origin of the efflorescences (our second aim), anionic chromatography analyses, X-ray diffraction measurements, and the isotopic determination of nitrogen were performed on the efflorescences (9 samples) and the salts recovered from the well (6 samples). Results of these analyses show that efflorescences are mainly made of potassium nitrate with a δ¹⁵N value of + 9.3 ± 0.2‰. Consequently, a plausible explanation for their formation could be the permeation of sewage water on the walls of the monumental complex.

Leonardo da Vinci's "Last Supper": a case study to evaluate the influence of visitors on the Museum preservation systems

The most important parameter to obtain an appropriate preservation condition of museum environments concerns the indoor air quality. The exposure of artwork and materials to gaseous and particulate pollutants introduced by visitors and either indoor or outdoor sources contributes to their decay. In this work, we evaluated the possible monitoring of the visitors' influence using the stable carbon isotopic ratio of CO₂ and the concentration of NH₃ as a real-time tool. The study was done in the Refectory of Santa Maria delle Grazie (Milan, Italy) which houses one of the most important paintings of Leonardo da Vinci, the Last Supper, and had more than 400,000 visitors in 2019. The results confirmed a good correlation between the presence of tourists inside the museum and the variation of δ¹³C value during the visits and the closure of the museum. The variation of indoor atmospheric δ¹³C was influenced by the presence of visitors in the Refectory and delineates the way done from the entrance to the exit. In the same way, the concentration of NH₃ was influenced by the presence of visitors and confirmed the role of this one on preservation methodology for indoor air quality in the museum. This new methodology can be used as a supplemental and non-invasive tool to help in calibrating microclimatic conditions through the ventilation rate and air filtration systems in the museum and to manage the number of visitors per turn.

New analytical approach to monitoring air quality in historical monuments through the isotopic ratio of CO2

In this study, we evaluated indoor air quality to highlight the effects of environmental pollution in the field of cultural heritage. In particular, two important archeological places in the old part of the city of Salerno, Italy, were analyzed: Fruscione Palace and S. Pietro a Corte. The work focused on the influence of tourists on environmental pollution correlated to indoor air quality during some social and cultural events. Moreover, we focused on the possible use of the carbon isotopic composition of CO₂ as a tool for environmental studies in the field of cultural heritage. The results showed a good relationship between the isotopic composition of CO₂ and the variation of pollutants concentration in the air, demonstrating that it is a valid tool and non-invasive marker to monitor environmental pollution of museums and cultural heritage sites.

The fascinating world of mayenite (Ca12Al14O33) and its derivatives

Mayenite (12CaO·7Al2O3) is a mesoporous calcium aluminum oxide, with a characteristic crystalline structure. The framework of mayenite is composed of interconnected cages with a positive electric charge per unit cell that includes two molecules [Ca24Al28O64]4+, and the remaining two oxide ions O2−, often labelled “free oxygen”, are trapped in the cages defined by the framework. Starting from mayenite structure several derivatives have been prepared through advanced synthetic protocols by free oxygen substitution with various anions. Mayenite and its derivates have been intensively investigated in many applications which include catalysis (oxidation and reduction, ammonia synthesis, pinacol coupling), environmental sensors and CO2 sorbent materials. In this review, we summarize our recent results on the main applications of mayenite and its derivatives.

Microplastics in the Environment: Intake through the Food Web, Human Exposure and Toxicological Effects

Recently, studies on microplastics (MPs) have increased rapidly due to the growing awareness of the potential health risks related to their occurrence. The first part of this review is devoted to MP occurrence, distribution, and quantification. MPs can be transferred from the environment to humans mainly through inhalation, secondly from ingestion, and, to a lesser extent, through dermal contact. As regards food web contamination, we discuss the microplastic presence not only in the most investigated sources, such as seafood, drinking water, and salts, but also in other foods such as honey, sugar, milk, fruit, and meat (chickens, cows, and pigs). All literature data suggest not-negligible human exposure to MPs through the above-mentioned routes. Consequently, several research efforts have been devoted to assessing potential human health risks. Initially, toxicological studies were conducted with aquatic organisms and then with experimental mammal animal models and human cell cultures. In the latter case, toxicological effects were observed at high concentrations of MPs (polystyrene is the most common MP benchmark) for a short time. Further studies must be performed to assess the real consequences of MP contamination at low concentrations and prolonged exposure.

Chemical risk in hospital settings: Overview on monitoring strategies and international regulatory aspects

Chemical risk in hospital settings is a growing concern that health professionals and supervisory authorities must deal with daily. Exposure to chemical risk is quite different depending on the hospital department involved and might origin from multiple sources, such as the use of sterilizing agents, disinfectants, detergents, solvents, heavy metals, dangerous drugs, and anesthetic gases. Improving prevention procedures and constantly monitoring the presence and level of potentially toxic substances, both in workers (biological monitoring) and in working environments (environmental monitoring), might significantly reduce the risk of exposure and contaminations. The purpose of this article is to present an overview on this subject, which includes the current international regulations, the chemical pollutants to which medical and paramedical personnel are mainly exposed, and the strategies developed to improve safety conditions for all healthcare workers.

Environmental and biological monitoring of formaldehyde inside a hospital setting: a combined approach to manage chemical risk in workplaces

Background: The safety of healthcare workers exposed to formaldehyde remains a great matter of concern for healthcare management units. This work aimed at describing the results of a combined monitoring approach (environmental and biological) to manage occupational exposure to formaldehyde in a hospital setting.

Design and Methods: Environmental monitoring of working spaces and biological monitoring of urinary formaldehyde in 16 exposed healthcare workers of the Anatomic Pathology Unit of a University Hospital in Southern Italy was performed on a fouryear timescale (2016-2019).

Results: Values of aero-dispersed formaldehyde identified were on average low; although workers’ urinary formaldehyde levels were also minimal, the statistical analysis highlighted a slight weekly accumulation.

Conclusions: Our data confirm that both environmental and biological monitoring are important to identify risk situations, in particular when values of hazardous compounds are below the accepted occupational exposure levels.

Development of a new radial passive sampling device for atmospheric NOx determination

In this paper we used Na₂CO₃-impregnated silica as reactive substrate for the determination of atmospheric NO_x (NO+NO₂) by using a passive sampling device, with radial symmetry, which is unprecedented. We conducted laboratory and field tests at an urban setting, with co-located passive samplers and continuous measurements of NO_x by a chemiluminescence detector, used as reference. The performance of the carbonate-based sorbent for the NO_x sampler was evaluated in two different time frames (autumn 2016 and winter 2017), characterised by different environmental conditions. The comparison of the NO_x concentration levels measured by passive sampling, using Na₂CO₃ as NO_x sorbent, showed a close relationship with those obtained by the chemiluminescence analyzer. Validation experiments in the laboratory and in the field are reported together with the calculation of the diffusion-sampling rate of the samplers.