Tracking the Spread of the BA.2.86 Lineage in Italy Through Wastewater Analysis.

The emergence of new SARS-CoV-2 variants poses challenges to global surveillance efforts, necessitating swift actions in their detection, evaluation, and management. Among the most recent variants, Omicron BA.2.86 and its sub-lineages have gained attention due to their potential immune evasion properties. This study describes the development of a digital PCR assay for the rapid detection of BA.2.86 and its descendant lineages, in wastewater samples. By using this assay, we analyzed wastewater samples collected in Italy from September 2023 to January 2024. Our analysis revealed the presence of BA.2.86 lineages already in October 2023 with a minimal detection rate of 2% which then rapidly increased, becoming dominant by January 2024, accounting for a prevalence of 62%. The findings emphasize the significance of wastewater-based surveillance in tracking emerging variants and underscore the efficacy of targeted digital PCR assays for environmental monitoring.

Short-term stability of wastewater samples for storage and shipment in the context of the EU Sewage Sentinel System for SARS-CoV-2.

In the context of an EU-wide surveillance system for SARS-CoV-2 in wastewater, recommended by the European Commission, this study aims to provide scientific support to the adequacy of transport and storage conditions of samples both in terms of duration and samples temperature. Three laboratories in Slovenia, Cyprus and Estonia investigated the short-term, one-week, isochronous stability of wastewater samples by RT-qPCR based detection of SARS-CoV-2 genes. The results were tested for statistical significance to determine uncertainty of quantification and shelf-life, at testing temperatures of + 20 °C and - 20 °C, relative to reference at + 4 °C. Samples were collected from three urban wastewater treatment plant influents and analysed respectively for SARS-CoV-2 genes N1, N2 (Laboratory 1), N2, E (Laboratory 2) and N3 (Laboratory 3), with various analytical methods. For a period of 7/8 days at + 20 °C, decreasing trends of measured concentrations were observed for all genes resulting in instability according to the statistical analysis, while at - 20 °C the trend of variation was stable only for N1, N2 (Laboratory 1) and N3 (Laboratory 3). Trends for gene E concentrations at - 20 °C (Laboratory 2) could not be tested statistically for stability because of lack of data. Over a period of just 3 days at + 20 °C, the variation was statistically non-significant indicating stability for genes N1, E and N3 for laboratories 1, 2 and 3, respectively. Nonetheless, the outcome of the study presents evidence to support the choice of the selected temperature at which samples shall be preserved during storage before analysis or transport to the laboratory. The conditions (+4 °C, ∼ few days) chosen for EU wastewater surveillance are in accordance with these results, highlighting the importance of stability testing of environmental samples to determine the short-term analytical uncertainty.

Cities as hotspots of indirect water consumption: The case study of Hong Kong.

During the last years, the city of Hong Kong has made large investments to make its urban water supply system more water efficient and sustainable. As such, its municipal water abstraction - often defined as direct water use - has decreased from 355 litre per capita per day (l/cap/d) in 2005 to 326 l/cap/d in 2013. Due to its political history, Hong Kong is unique in the world in data availability on urban food consumption. It is therefore the ideal case study to show typical urban food consumption behaviour and its related indirect water use. The objective of this paper is to show the large water quantities associated with indirect water use and that the citizens of Hong Kong can additionally save much more water by looking at this indirect water use. The current average diet in Hong Kong is very different to the average Chinese diet. It is characterised by a high intake of water intensive products like animal products and sugar, leading to a food related indirect water use or water footprint (WFcons) of 4727 l/cap/d. According to recommendations from the Chinese Nutrition Society for a healthy diet, the intake of some product groups should be increased (vegetables and fruit) and of other product groups reduced (sugar, crop oils, meat and animal fats). This would result in a reduction of the WFcons of 40% to 2852 l/cap/d. Especially the reduced intake of meat (including offals) from currently 126 kg per capita per year (kg/cap/yr) to the recommended value 27 kg/cap/yrwould results in a substantial WFcons reduction. Meat consumption in Hong Kong is extremely high. A pesco-vegetarian diet would result in a reduction of 49% (to 2398 l/cap/d) and a vegetarian diet in a 53% (to 2224 l/cap/d) reduction. Hong Kong citizens can thus save a lot of water through a change in their diet. Many of the products consumed, contribute to different levels of blue water scarcity in the regions of origin Hong Kong imports from. This poses a water-related risk to food security in Hong Kong. As all diet scenarios also result in a lower blue WFcons, they decrease this risk. In order to become sustainable, (mega)cities should reduce their dependency on distant resources and ecosystems.

Water consumption related to different diets in Mediterranean cities.

Providing the sustainable development goals (SDGs) water, food and energy security to cities relies strongly on resource use outside city borders. Many modern cities have recently invested in a sustainable urban water system, and score high in international city rankings regarding water management and direct urban water use. However, these rankings generally neglect external resource use for cities. Here we quantify the water resources related to food consumption in thirteen cities located in Mediterranean countries, by means of the water footprint (WF) concept. These WFs amount from 3277l per capita per day (l/cap/d) to 5789l/cap/d. These amounts are about thirty times higher than their direct urban water use. We additionally analyse the WF of three diet scenarios, based upon a Mediterranean dietary pattern. Many authors identify the Mediterranean diet as cultural heritage, being beneficial for human health and a model for a sustainable food system. The first diet scenario, a healthy Mediterranean diet including meat, leads to WF reductions of -19% to -43%. The second diet scenario (pesco-vegetarian), leads to WF reductions of -28% to -52%. The third diet scenario (vegetarian), leads to WF reductions of -30% to -53%. In other words, if urban citizens want to save water, they need to look at their diets.

Urban food consumption and associated water resources: The example of Dutch cities.

Full self-sufficiency in cities is a major concern. Cities import resources for food, water and energy security. They are however key to global sustainability, as they concentrate a rapidly increasing and urbanising population (or number of consumers). In this paper, we analysed the dependency of urban inhabitants on the resource water for food consumption, by means of Dutch cities. We found that in extremely urbanised municipalities like Amsterdam and Rotterdam, people eat more meat and cereals and less potatoes than in other Dutch municipalities. Their current water footprint (WF) related to food consumption is therefore higher (3245l/cap/day) than in strongly urbanised cities (3126l/cap/day). Dutch urban citizens who eat too many animal products, crop oils and sugar can reduce their WF (with 29 to 32%) by shifting to a healthier diet. Recommended less meat consumption has the largest impact on the total WF reduction. A shift to a pesco-vegetarian or vegetarian diet would require even less water resources, where the WF can be reduced by 36 to 39% and 40 to 42% respectively. Dutch cities such as Amsterdam have always scored very high in international sustainability rankings for cities, partly due to a long history in integrated (urban) water management in the Netherlands. We argue that such existing rankings only show a certain - undoubtedly very important - part of urban environmental sustainability. To communicate the full picture to citizens, stakeholders and policy makers, indicators on external resource usage need to be employed. The fact that external resource dependency can be altered through changing dietary behaviour should be communicated.

The application of positive matrix factorization in the analysis, characterisation and detection of contaminated soils.

Multivariate factor analytical techniques are widely used for the approximation, in terms of a linear combination of factors, of multivariate experimental data. The chemical composition of soil samples are multivariate in nature and provide datasets suitable for the application of these statistical techniques. Recent developments of multivariate factor analytical techniques have led to the approach of Positive Matrix Factorization (PMF), a weighted least squares fit of a data matrix in which the weights are determined depending on the error estimates of each individual data value. This approach relies on more physically significant assumptions than methods like Principal Components Analysis which is frequently used in the analysis of soil datasets. In this paper we apply PMF to characterise the pollutant source in a set of geographically referenced soil samples taken within a 200 m radius of a site characterised by a high concentration of heavy metals. Each sample has been analysed for major and minor elements (using wavelength-dispersive X-ray fluorescence spectrometry), carbon, hydrogen and nitrogen (using a CHN elemental analyzer) and mercury (using cold-vapour atomic absorption spectrometry). Analysis of the soils using PMF resulted in a successful partitioning of variances into sources related to background soil geochemistry, organic influences and those associated with the contamination. Combining these results with a geostatistical approach successfully demarcated the main source of the combined organic and heavy metal contamination.

Certified reference materials to support a European thematic strategy for soil protection: the EUROSOILS (IRMM-443) experience.

The recent proposal of thematic strategy for soil protection by the European Commission outlines that knowledge of problems associated with soil has increased considerably based on surveys, monitoring systems and data networks. Although this information is very useful, its value for the policy-making process is limited due to a lack of comparability. From this unsatisfying situation the need arises to develop an EU-wide monitoring system accompanied by suitable matrix reference materials. Experiences gained from the development and certification of IRMM-443 (The EUROSOILS) show how to approach the complex problem of providing suitable (i.e. representative) soil CRMs for the arising analytical needs to support existing and upcoming EU legislation. This paper presents briefly the quantitative findings of a certification exercise (adsorption coefficients for atrazine, lindane and 2,4-D, as well as pH in suspension). A comparison of these results with those of an intercomparison exercise organised in 1989 by the German UBA on very similar soils shows the significant improvement in the determination of soil adsorption coefficients that was induced by the EUROSOIL project. Indicative values of total and organic carbon content and nitrogen according to ISO Standards are also presented.Furthermore, the idea of reference soils and derived reference materials (for analytical purposes) as well as reference matrices (substrates for ecotoxicological testing) is highlighted and set into the context of horizontal standardisation of methods.

Preservation of sensitive CRMs and monitoring their stability at IRMM.

Over the years, the nature of CRMs has changed considerably. Recently, more and more CRMs have been certified in their "natural" form, that is processed as little as possible, with analytes at their natural concentration level. This and the trend towards certified properties other than the concentrations of clearly defined molecules/elements have made guaranteeing stability of CRMs and estimating a shelf life an even more important issue for reference material producers than it has been before. One way to meet this challenge is to take more care in processing, storage and dispatch of CRMs. At IRMM, approximately 20 % of the RMs are stored at -20 degrees C or below and about 10% require cooled transportation. In addition, increased efforts for assessing stability are needed. Shelf lives are estimated using addition of an uncertainty component based on real-temperature stability studies rather than by accelerated stability studies. These pre-certification efforts are complemented by a stability-monitoring program, which at IRMM includes 80 % of the non-nuclear and non-isotopic materials. Although the costs for these efforts are high in absolute terms, they are only a minor and indispensable contribution to the total costs of CRM production.

Certification of the European reference soil set (IRMM-443--EUROSOILS). Part I. Adsorption coefficients for atrazine, 2,4-D and lindane.

The European Commission has characterised and certified a set of six European soils (the EUROSOILS) under the number IRMM-443. After a successful validation and trial period with a preliminary batch it was decided to produce a new batch of certified reference materials. Part I of this paper describes the certification of adsorption coefficients for atrazine, 2,4-D and lindane in these soils. The adsorption coefficients were determined according to OECD Test Guideline 106. Additionally, the underlying principles for the value assignment process according to the GUM and their practical application to the numerical data obtained during the certification exercise according to ISO Guide 34 and 35 are discussed.

Certification of the European Reference Soil Set (IRMM-443--EUROSOILS). Part II. Soil-pH in suspensions of water and CaCl2.

IRMM-443 re-groups a set of six European Reference Soils (EUROSOILS), which had been certified for their adsorption coefficients for atrazine, 2,4-D and lindane (Certification of the European Reference Soil Set (IRMM-443-EUROSOILS)-Part I. Adsorption coefficients for atrazine, 2,4-D and lindane. Sci Total Environ, in press). The certification of these parameters was complemented by an additional certification of pH in suspension as well by the determination of indicative values for total nitrogen, organic and total carbon content. While Part I explained the principles of the value assignment process and discussed their application to the adsorption coefficients, Part II presents the certified values for pH as well as the indicative values for N(tot), C(tot) and C(org). In addition, the assessment of uncertainty components for stability and homogeneity, which have been included in the final uncertainty budget, is discussed.

Comparison of different extraction techniques for the determination of polychlorinated organic compounds in sediment.

The performance of various enhanced extraction techniques, such as accelerated solvent extraction, microwave-assisted extraction, Soxhlet extraction, ultrasonic extraction and fluidized-bed extraction for the determination of polychlorinated organic compounds in dry sediment was investigated in two laboratories. The results of the two laboratories were in good agreement. The extraction yields from the batch extraction methods were lower than those from the dynamic techniques. Accelerated solvent extraction, especially, exhibited higher extraction efficiency than the standard procedure, Soxhlet extraction, whereas the results of fluidized-bed extraction were comparable.

EUROSOILS--a set of CRMs for comparability of soil-measurements.

An overview is given on the development, properties, and application of the European reference soil set--the EUROSOILS. The introduction of this new type of reference material has, for the first time, enabled comparison of data related to the interaction of chemical substances with the soil, and thus, improvement of soil quality. Because of their unforeseen success, a second generation of EUROSOILS had been produced and the range of application extended to other types of measurement related to the soil matrix--soil pH, carbon and nitrogen content, particle-size distribution and cation-exchange capacity. Other fields of application include analytical method development or testing of soil decontamination techniques. On the basis of the success of the EUROSOIL concept and the need for a common basis for comparison of soil-related data in Europe and beyond, the European Commission's Institute for Reference Materials and Measurements decided to certify several properties of the second EUROSOIL-generation, thus establishing a common QA/ QC system for soil-related data. The main features of the EUROSOILS, their origin, the necessary field and laboratory work, and some interesting background information about the project are presented in this paper.

Organic contaminants in water--conceptual considerations for the production of liquid reference materials in support of the new water framework directive.

The lack of suitable certified reference materials for the determination of organic pollutants in water has become a major problem within the framework of the new European water policy. This paper highlights approaches towards the production of certified reference materials and their drawbacks. On the basis of experience gained from proficiency-testing schemes, analytical practice, and reference material production a new concept for the production of liquid reference materials to be used in support of European legislation is presented and discussed briefly. The concept is based on a standard-addition approach and the simulation of effects interfering with the analytical process by use of individual matrix constituents or matrix-mimicking substances in combination with water-miscible solvents. The concept enables quantification of dissolved organic compounds in unknown water samples and evaluation of the analytical process with the help of a reconstituted sample. Open questions for further research are also outlined.

Polychlorinated organic compounds in Yangtse River sediments.

Polychlorinated organic compounds (PCOCs) were analyzed in Yangtse River sediments. The results show that the concentrations of PCOCs in Yangtse River sediments followed the order of DDTs > HCB > HCHs > PCBs. High PCOCs concentrations were detected in sediments from station Y02a and Y02b, which are located in the main input of the Yangtse River (Nanjing section). Results also show that the PCOCs values were highly correlated with organic carbon content and heavy metal contamination.

Estimation of soil adsorption coefficients of organic compounds by HPLC screening using the second generation of the European reference soil set.

The European reference soil set was introduced as common basis for a better comparability of soil sorption data measured within the framework of chemical testing of environmental chemicals. The success of the EUROSOILS, as the set is commonly called, convinced the European Commission's Joint Research Centre to evaluate the possibility of producing a remake of these unique and new type of reference materials maintaining the principal sorption-controlling properties of the soils. In this paper the recently proposed second generation of the EUROSOILS is used to evaluate a HPLC-screening technique for the estimation of soil adsorption coefficients of organic chemicals. It could be shown that the derived correlations between HPLC capacity factors of the test substances and the respective soil adsorption coefficients resulting from batch experiments with the second version of the EUROSOILS agreed with those derived for the first generation of reference soils at a different occasion.

River sediment (S-37)--a new analytical quality control material ensuring comparability of chlorinated hydrocarbon analysis during an international environmental study in China.

A sediment reference material (S-37) was prepared as analytical quality control material to be used within an international project on polychlorinated hydrocarbon analysis in two Chinese rivers. The raw material was sampled during a cruise on Yangtse River and transported afterwards to the JRC Ispra for further processing. The material was treated according to the general principles applicable for candidate reference material production. After a thorough homogeneity study of the bulk the material was bottled. A total of 1,080 bottles each containing 50 g of dry sediment powder was obtained. Final homogeneity and stability testing proved the material to be fit for the purpose. Isotope dilution GC/MS was used to establish target values for pentachlorobenzene (1.17 +/- 0.08 ng/g), hexachlorobenzene (3.60 +/- 0.17 ng/g), octachlorostyrene (0.19 +/- 0.01 ng/g), pentachloroanisole (0.52 +/- 0.02 ng/g), alpha-HCH (0.70 +/- 0.05 ng/g), beta-HCH (1.38 +/- 0.18 ng/g), gamma-HCH (0.83 +/- 038 ng/g), 2,4'-DDT (0.36 +/- 0.04 ng/g), 2,4'-DDE (0.29 +/- 0.02 ng/g), 2,4'-DDD (0.49 +/- 0.02), 4,4'-DDT (3.42 +/- 0.47 ng/g), 4,4'-DDD (1.29 +/- 0.17 ng/g), PCB 28 (0.11 +/- 0.01 ng/g), PCB 52 (0.09 +/- 0.003 ng/g), PCB 101 (0.07 +/- 0.003 ng/g), PCB 138 (0.06 +/- 0.003 ng/g) and PCB 153 (0.06 +/- 0.003 ng/g). Furthermore, indicative values for major and minor constituents as well as for polychlorinated dibenzodioxines and -furanes were measured.

On the presence of PCDD/Fs and other chlorinated hydrocarbons in the second generation of the European Reference Soil Set--the EUROSOILS.

The second generation of the European Reference Soil-Set, the so-called EUROSOILS, has been introduced recently. The presence of organic micro-pollutants in this new type of reference materials has already been studied for polycyclic aromatic hydrocarbons, triazines, phenylureas and other pesticides. The already large amount of data concerning the level of different contaminants, the elemental composition and matrix properties is completed by a survey by means of GC/MS on the polychlorinated dibenzodioxins/furans (PCDD/Fs) and other chlorinated hydrocarbons. Higher concentrations for 4,4'-DDT in EUROSOIL 2 (10.57 +/- 0.02 ng/g), for dieldrin in EUROSOIL 3 (8.85 +/- 0.87 ng/g) and for heptachlor-epoxide in EUROSOIL 4 (5.86 +/- 0.16 ng/g) could be detected. Sum concentrations for PCDD/Fs were 15.02 ng/kg (EUROSOIL 1), 214.29 ng/kg (EUROSOIL 2), 873.32 ng/kg (EUROSOIL 3), 54.47 ng/kg (EUROSOIL 4) and 119.61 ng/kg (EUROSOIL 5).