12 Years of honey surveys in northern Italy: How anthropic activities can influence honey quality.

Bees and hive products, such as honey, can act as indicators of environmental quality. Our research aimed to evaluate historical data of honey quality in Lombardy (Northern Italy) and consider the possible sources of air contamination that can influence it. We collected analytical data from the local Health Protection Agency on residues of 57 honey samples from 2011 to 2022, comparing a rural area and an industrial area. At the same time, we consulted estimated air emissions in the same areas through the INEMAR database used by the local Environmental Protection Agency. Data revealed antibiotic contamination in one case and, regarding heavy metals, lead contamination in several samples in the industrial area. Pb contamination could derive from multiple sources. The INEMAR database permitted us to hypothesize that combustion in industry and road transportation could have a role in honey contamination, being among the main sources of Pb emission in that area.

On the concentration of SARS-CoV-2 in outdoor air and the interaction with pre-existing atmospheric particles.

The spread of SARS-CoV-2 by contact (direct or indirect) is widely accepted, but the relative importance of airborne transmission is still controversial. Probability of outdoor airborne transmission depends on several parameters, still rather uncertain: virus-laden aerosol concentrations, viability and lifetime, minimum dose necessary to transmit the disease. In this work, an estimate of outdoor concentrations in northern Italy (region Lombardia) was performed using a simple box model approach, based on an estimate of respiratory emissions, with a specific focus for the cities of Milan and Bergamo (Italy). In addition, the probability of interaction of virus-laden aerosol with pre-existing particles of different sizes was investigated. Results indicate very low (<1 RNA copy/m3) average outdoor concentrations in public area, excluding crowded zones, even in the worst case scenario and assuming a number of infects up to 25% of population. On average, assuming a number of infects equal to 10% of the population, the time necessary to inspire a quantum (i.e. the dose of airborne droplet nuclei required to cause infection in 63% of susceptible persons) would be 31.5 days in Milan (range 2.7-91 days) and 51.2 days in Bergamo (range 4.4-149 days). Therefore, the probability of airborne transmission due to respiratory aerosol is very low in outdoor conditions, even if it could be more relevant for community indoor environments, in which further studies are necessary to investigate the potential risks. We theoretically examined if atmospheric particles can scavenge virus aerosol, through inertial impact, interception, and Brownian diffusion. The probability was very low. In addition, the probability of coagulation of virus-laden aerosol with pre-existing atmospheric particles resulted negligible for accumulation and coarse mode particles, but virus-laden aerosol could act as sink of ultrafine particles (around 0.01 µm in diameter). However, this will not change significantly the dynamics behaviour of the virus particle or its permanence time in atmosphere.

Results of an interlaboratory comparison of analytical methods for quantification of anhydrosugars and biosugars in atmospheric aerosol.

An interlaboratory comparison was performed to evaluate the analytical methods for quantification of anhydrosugars - levoglucosan, mannosan, galactosan - and biosugars - arabitol, glucose and mannitol - in atmospheric aerosol. The performance of 10 laboratories in Italy currently involved in such analyses was investigated on twenty-six PM (particulate matter) ambient filters, three synthetic PM filters and three aqueous standard solutions. An acceptable interlaboratory variability was found, determined as the mean relative standard deviation (RSD%) of the results from the participating laboratories, with the mean RSD% values ranging from 25% to 46% and decreasing with increasing sugar concentration. The investigated methods show good accuracy, evaluated as the percentage error (ε%) related to mean values, since method biases ranged within ±20% for most of the analytes measured in the different laboratories. The detailed investigation (ANOVA analysis at p < 0.05) of the contribution of each laboratory to the total variability and the measurement accuracy shows that comparable results are generated by the different methods, despite the great diversity in terms of extraction conditions, chromatographic separation - more recent LC (liquid chromatography) and EC (exchange chromatography) methods compared to more widespread GC (gas chromatography) - and detection systems, namely PAD (pulsed amperometric detection) or mass spectrometry.

Measurement of the carbonaceous component in the Milan urban particulate matter.

The carbonaceous component in the Milan urban particulate matter, i.e. the two components black carbon (BC) and organic carbon (OC), has been measured by means of a thermogravimetric analyzer combined with an infrared spectrophotometer (TGA/FT-IR). While black carbon may be considered a primary pollutant, organic carbon includes both primary emissions and secondary organic aerosols. Since carbonaceous aerosol (including a small quantity of inorganic carbon, too) makes up roughly from 25% to 50% of the average annual PM 2.5 mass concentration, a deeper understanding of this component is required. The TGA/FT-IR technique, employed for the first time to our knowledge for the quantification of the particulate matter carbonaceous component, allows, thought the results here presented are preliminary, to assess the two components BC and OC in a simple way especially if compared with the methods reported in the literature. The total carbon (TC) determinations performed by TGA/FT-IR on Milan urban particulate matter are in good agreement with the results obtained by a total organic carbon (TOC) analyzer operating directly on the solid sample.