Reviewing the use of zebrafish for the detection of neurotoxicity induced by chemical mixtures through the analysis of behaviour.

The knowledge and assessment of mixtures of chemical pollutants in the aquatic environment is a complex issue that is often challenging to address. In this review, we focused on the use of zebrafish (Danio rerio), a vertebrate widely used in biomedical research, as a model for detecting the effects of chemical mixtures with a focus on behaviour. Our aim was to summarize the current status of the ecotoxicological research in this sector. Specifically, we limited our research to the period between January 2012 and September 2023, including only those works aimed at detecting neurotoxicity through behavioural endpoints, utilizing zebrafish at one or more developmental stages, from egg to adult. Additionally, we gathered the findings for every group of chemicals involved and summarised data from all the works we included. At the end of the screening process 101 papers were considered eligible for inclusion. Results show a growing interest in zebrafish at all life stages for this kind of research in the last decade. Also, a wide variety of different assays, involving different senses, was used in the works we surveyed, with exposures ranging from acute to chronic. In conclusion, the results of this study show the versatility of zebrafish as a model for the detection of mixture toxicity although, for what concerns behavioural analysis, the lack of standardisation of methods and endpoints might still be limiting.

One health adoption within prevention, preparedness and response to health threats: Highlights from a scoping review.

Introduction: As the COVID-19 pandemic has demonstrated, the complexity of factors involved in the emergence of health threats requires a holistic One Health (OH) approach to enhance the effectiveness of prevention, preparedness, and response (PPR) strategies. Therefore, we conducted a scoping review to explore how the OH approach has been adopted in the context of PPR strategies to health threats, and the challenges and benefits deriving from its integration. Methods: We defined the research questions and a strategy to guide the peer-reviewed and grey literature search to identify relevant articles and documents (identification). We assessed them for eligibility according to predefined criteria (screening) and finally included the ones that answered the research questions (inclusion). We performed a descriptive and thematic analysis of the results. Results: A total of 138 records were included in the review (57 from the peer-reviewed literature and 81 from the grey literature). The OH approach was mainly adopted in prevention strategies, particularly within the governance area. Human and animal health were the most integrated disciplines in the OH approach, while environmental and social sciences were the less integrated. The most targeted threats were antimicrobial resistance and zoonoses, with the African region being the most represented. Conducive factors for the adoption of OH PPR strategies were identified in resolutions and guidance emanating from international organisations. Discussion: The global governance of OH should utilise conducive factors, such as international resolutions and guidance, to enhance the adoption of multisectoral and multi-actor PPR strategies, that focus on national and international priorities and neglected threats, such as environmental hazards and pandemic risk. Integrated frameworks and metrics for the implementation and evaluation of OH PPR strategies need to be consolidated to contribute to the growing body of evidence supporting the adoption of the OH approach.

Mercury (Hg) and methylmercury (MeHg) in sediment and biota: A case study in a lagoon in Central Italy.

A quantification of total mercury (Hgtot) and methylmercury (MeHg) concentrations in sediment and mussels was carried out in the east basin of the Orbetello lagoon in order to assess their bioaccumulation potential. The sediment was sampled in four macroareas, mussels were transplanted in the same sites and collected after seven weeks. The results show that Hgtot concentrations in sediments exceeded (0.21-16.9 mg/kg dry weight (dw)) the environmental quality standard of the Italian legislation (0.3 mg/kg dw). The Hgtot concentration in mussels (0.050-0.324 mg/kg wet weight (ww)) does not exceed the limit values (0.5 mg/kg ww) of the European food legislation. The biota-sediment accumulation factors (BSAFs) derived for MeHg (80-306.7) and a biomagnification factor (BMF) greater than 1 for Hgtot demonstrate that in the lagoon, these compounds can be transferred in the upper levels of the trophic chain and pose a risk to human health.

An integrated approach for chemical water quality assessment of an urban river stretch through Effect-Based Methods and emerging pollutants analysis with a focus on genotoxicity.

The impact of emerging chemical pollutants, on both status and functionality of aquatic ecosystems is worldwide recognized as a relevant issue of concern that should be assessed and managed by researchers, policymakers, and all relevant stakeholders. In Europe, the Reach Regulation has registered more than 100.000 chemical substances daily released in the environment. Furthermore, the effects related to the mixture of substances present in aquatic ecosystems may not be predictable on the basis of chemical analyses alone. This evidence, coupled with the dramatic effects of climate changes on water resources through water scarcity and flooding, makes urgent the application of innovative, fast and reliable monitoring methods. In this context, Effect-Based Methods (EBMs) have been applied in the urban stretch of the Tiber River (Central Italy) with the aim of understanding if detrimental pressures affect aquatic environmental health. In particular, different eco-genotoxicological assays have been used in order to detect genotoxic activity of chemicals present in the river, concurrently characterized by chemical analysis. Teratogenicity and embryo-toxicity have been studied in order to cover additional endpoints. The EBMs have highlighted the presence of diffuse chemical pollution and ecotoxicological effects in the three sampling stations, genotoxicological effects have been also detected through the use of different tests and organisms. The chemical analyses confirmed that in the aquatic ecosystems there is a diffuse presence, even at low concentrations, of emerging contaminants such as pharmaceuticals, not routinely monitored pesticides, personal care products, PFAS. The results of this study can help to identify an appropriate battery of EBMs for future studies and the application of more appropriate measures in order to monitor, mitigate or eliminate chemical contamination and remediate its adverse/detrimental effects on the ecosystem health.

Need for a sustainable use of medicinal products: environmental impacts of ivermectin.

It is worldwide recognized that the use of pharmaceuticals for human and veterinary purposes could lead to unsustainable effects on the environment. A strategy to reduce the impact of pharmaceuticals on the environment has been recently established at European level, where guidelines to evaluate the impacts of veterinary drugs used to treat animal diseases are in place. The aim of this article is to focus on the worldwide used antiparasitic drug ivermectin (IVM) and its potential impact on the environment. A specific section is related to the IVM resistance that the massive use of this drug could generate enhancing the risk scenarios also for human health. The application of stringent measures for the veterinary use of this substance, in line with the recommendations provided by International frameworks such as One Health and EcoHealth, is recommended.

Application of effect-based methods (EBMs) in a river basin: a preliminary study in Central Italy.

INTRODUCTION: Effect-based methods (EBMs), i.e. in vitro and in vivo bioassays, represent innovative tools for the effect detection of environmental chemical pollutants on living organisms. The aim of this study was to evaluate the water quality of a river ecosystem implementing two in vivo bioassays on target freshwater animal species: the crustacean Daphnia magna and the small fish Danio rerio, also known as zebrafish. MATERIALS AND METHODS: The methods applied in this study, i.e. the Daphnia sp. Acute Immobilisation assay and the Fish Embryo Acute Toxicity (FET) test, are commonly used in water quality research and their application in short-term ecotoxicity detection is suggested by recent European projects. Two sampling sites were chosen in the urban part of the Tiber River in Rome, while a third one was chosen as a reference site in the Farfa River, a tributary upstream of the city. The sites in the Tiber River are potentially affected by different pollution sources, including urban and industrial wastewater discharges, the pesticide release, livestock waste products, and waste dumps. RESULTS AND DISCUSSION: The results of the study showed wide differences between the two applied bioassays. The FET test was generally more sensitive in detecting even low effects in all the water samples, but the strongest statistically results were observed with the D. magna Acute Immobilisation test. The results of this research confirm the effectiveness of EBMs in investigating and monitoring water chemical pollution, and stress the need for performing further studies, e.g. chemical analyses and other bioassays, to improve the knowledge of the health status of the Tiber River basin. CONCLUSIONS: Further results will aim to support the local authorities in adopting measures to reduce and to eliminate the sources of chemical pollution in the study area.

Quantification and genetic diversity of Hepatitis E virus in wild boar (Sus scrofa) hunted for domestic consumption in Central Italy.

Hepatitis E is an emerging disease in industrialized countries. The food-borne transmission of hepatitis E virus (HEV) is associated principally with products derived from the domestic pig, the wild boar, and deer; however, few quantitative data are available on HEV loads in animals used in food production. This study assessed HEV occurrence, viral load and genetic variability in wild boar hunted for domestic consumption in the district of Viterbo (Central Italy) where high anti-HEV IgG seroprevalence values are reported in humans. A total of 332 liver and 69 intestine samples were obtained from wild boar hunted between 2011 and 2014. The liver tissue in 54 of the animals (16.3%) was HEV-positive. Viral loads in quantifiable liver samples (n = 29) ranged between 3.2 × 102 and 3.8 × 105 genome copies (g.c.)/g with a mean value of 1.85 × 104 g.c./g. A statistically significant positive correlation was found between viral concentration in liver and intestinal tissue, though mean viral load in the intestines was lower (3.13 × 103 g.c./g). Twenty-six samples were characterized molecularly as genotype 3 (G3) and four subtypes (a, c, f and l) were detected. Finally, twelve samples with near identical sequences were identified as G3 but could not be assigned to any of the known subtypes, and could therefore represent a potentially new subtype.