WHO Laboratory Biosafety Manual: A New Approach to Security.

The paper aims to highlight the new indications introduced in the 4th edition of the "Laboratory Biosafety Manual" of World Health Organization. The authors propose a new vision to improve biosafety and biosecurity in the laboratory aligned with the technical standards ISO 35001:2019 "Biorisk management for laboratories and other related organizations" and ISO 45001:2018 "Occupational health and safety management systems-Requirements with guidelines for use" framework. The current edition has a more innovative approach compared to the previous ones, more attention is given to training awareness and providing skills, to promote the culture of safety by adopting an approach based on risk analysis, rather than the prescriptive approach that has been used previously.

In Vitro and In Vivo Biocompatibility Studies on Engineered Fabric with Graphene Nanoplatelets.

To produce clothes made with engineered fabrics to monitor the physiological parameters of workers, strain sensors were produced by depositing two different types of water-based inks (P1 and P2) suitably mixed with graphene nanoplatelets (GNPs) on a fabric. We evaluated the biocompatibility of fabrics with GNPs (GNP fabric) through in vitro and in vivo assays. We investigated the effects induced on human keratinocytes by the eluates extracted from GNP fabrics by the contact of GNP fabrics with cells and by seeding keratinocytes directly onto the GNP fabrics using a cell viability test and morphological analysis. Moreover, we evaluated in vivo possible adverse effects of the GNPs using the model system Caenorhabditis elegans. Cell viability assay, morphological analysis and Caenorhabditis elegans tests performed on smart fabric treated with P2 (P2GNP fabric) did not show significant differences when compared with their respective control samples. Instead, a reduction in cell viability and changes in the membrane microvilli structure were found in cells incubated with smart fabric treated with P1. The results were helpful in determining the non-toxic properties of the P2GNP fabric. In the future, therefore, graphene-based ink integrated into elastic fabric will be developed for piezoresistive sensors.

Round-Robin Tests with Relocatable Coverslips Improve Asbestos Fibre Counting.

Asbestos fibre counting by phase-contrast microscope is subject to many sources of variation, including those dependent on the analyst. In this study, asbestos sample slides prepared with relocatable coverslips have been used for fibre counting among voluntary analysts to evaluate their proficiency. One slide of amosite and one of chrysotile were distributed to all the analysts, and three proficiency testing rounds were conducted for amosite and four for chrysotile. Each relocatable coverslip has a report in which are reported for each viewing field both the number of certified fibres (Verified Fibres) and a drawing representing the shape and position of the individual fibres. In the first round, the analysts were asked to report only the number of fibres counted in each of the predesignated fields of view. In the other rounds, subsequently developed, the analysts had to report the number and the position of the fibres for each field. The reported number of fibres and their position in each of the designed fields were evaluated against their respective verified fibres, to identify types of error. Discrepancies between reported fibres and verified fibres in each field of view have been used to evaluate the proficiency of the analysts. The discrepancies can be positive (D+) or negative (D-) depending on whether the analyst counts, for a specific field of view, more or less fibres compared to the verified fibres. The score is calculated using the following equation: Score = (1 - ∑D+ + ∑│D-│/VF) × 100. An analyst obtaining a score of ≥60, which corresponds to (∑D+ + ∑│D-│)/VF ≤ 0.40, is proficient. The number of laboratories that participating in this study varied from 13 to 17 depending on the rounds. For amosite fibre counts, the results were generally good compared to a proficiency score of 60. The major error made by analysts was the counting of fibres shorter than 5 µm, where this error was of 62% of extra fibres and accounted for 8% over-estimation of amosite fibres. For chrysotile, a score of ≥50 has been used to consider an analyst as proficient. The results of chrysotile fibres showed that in the first round all analysts counted less than fifty per cent of the verified fibres. In the second round 10 analysts out of 13 reached a score of ≥50, 8 of 16 in the third and 10 of 12 in the fourth. For chrysotile fibres, the error relating to the counting of fibres shorter than 5 µm was of 56% of extra fibres, but the error that most influenced the results was the number of oversight-missing fibres. This type of error accounted for 97% of the missing fibres and for the 29% under-estimation of the chrysotile fibres. For amosite fibre counting, results of this study show an improvement of the analyst's performance. For the chrysotile fibre count, although there is a significant improvement in the comparison between some rounds, this is not continuous over time.

Analysis of major pollutants and physico-chemical characteristics of PM2.5 at an urban site in Rome.

Air quality data from a one year study at an urban roadside location in Rome are reported for major pollutants. Continuous concentration data of carbon monoxide, ozone, nitrogen dioxide, aromatic hydrocarbons and natural radioactivity were measured in the urban air of Rome from January 2016 to January 2017. Moreover, PM2.5 mass concentration and physico-chemical characteristics of single constituent particles are herein reported. Gaseous pollutants, except ozone, and PM2.5 showed maximum concentrations in December due to high atmospheric stability. O3 and NO2 trend analysis showed photochemical smog episodes in June and September. In September, during a photochemical smog episode the aromatic hydrocarbons contribution to ozone formation was experimentally proven. Pearson's coefficient among aromatic hydrocarbons and the ratio Toluene/Benzene (T/B) showed that pollutants were under the influence of vehicular traffic. Physico-chemical characterization of PM2.5 single particles, carried out by field emission scanning electron microscope combined with energy dispersive X-ray spectroscopy, displayed the presence of particle diversity from natural and anthropogenic origin. Four principal components in the PM2.5 were identified: carbonaceous particles, Ca-sulphates, soil dust and building structure particles, metal particles. The principal source of carbonaceous particles in this urban area consists of the motor vehicle exhausts and the heating systems in winter. Traces of S and sometimes S, Na, K were detected on varying percentages of carbonaceous particles. These data suggested that the carbonaceous particles act as vehicles for strong acids, prevalently H2SO4 and alkaline metal sulphates. A Saharan dust contribution to PM2.5 was found in different periods. Metal particles included iron oxide particles, metals oxide particles and Fe-rich metal compounds. The identification of chemical composition of individual particles provide useful information to determine their origin and formation processes.

Characterization and distribution of petroleum hydrocarbons and heavy metals in groundwater from three Italian tank farms.

The present paper highlights the utility of petroleum chemical fingerprinting in investigating known or suspected tank farm releases. A detailed characterization of groundwater was carried out in three tank farms located in north, central and south Italy. Eighteen parent polycyclic aromatic hydrocarbons (naphthalene through coronene), n-alkanes (n-C(10) through n-C(36)), isoprenoids pristane and phytane, vanadium, nickel and lead were determined. Distribution profiles and diagnostic ratios of specific fuel constituents were studied in order to identify contamination sources. Data analysis shows that in the study sites multiple pollutant sources affecting the tank farms and the surrounding industrial areas are present. Both high concentrations of contaminants coming from fuel releases and noticeable concentrations of biogenic compounds were found. A detailed data analysis suggests the origin and the level of pollution of the three sites. The results demonstrate that threshold concentration approach is not always sufficient and it is necessary to carry out studies of contaminant distribution and their diagnostic ratios in order to perform a successful forensic investigation.

Air pollutants and the characterization of the organic content of aerosol particles in a mixed industrial/semi-rural area in central Italy.

Both regulated and unregulated air pollutants were detected during an intensive seasonal sampling campaign in a mixed industrial/semi-rural area on the outskirts of Rome, Italy, at two sites located opposite a hospital waste incinerator, downwind according to the direction of the prevailing local winds. Concentrations of pollutants were significantly lower than in urban atmospheres. The composition of particulate organic material indicated a heavy biogenic impact, accompanied by a lower contribution from petroleum-related processes. Both PAH and nitro-PAH group compositions of particulates were used to assess the nature and relative importance of sources. Both sites showed that different and diffuse sources contributed to local pollution with a significant contribution from traffic, proving that the hospital waste incinerator was not the main pollution source in this area. Among unregulated compounds, a series of positional isomers of nitro-PAHs and other organic compounds associated with particulate matter were investigated. In particular, 1- and 3-nitrophenanthrene identification was carried out, and they proved to be the most abundant nitro-PAHs.