OECD harmonised template 201: Structuring and reporting mechanistic information to foster the integration of new approach methodologies for hazard and risk assessment of chemicals.

In the European Union, the Chemicals Strategy for Sustainability (CSS) highlights the need to enhance the identification and assessment of substances of concern while reducing animal testing, thus fostering the development and use of New Approach Methodologies (NAMs) such as in silico, in vitro and in chemico. In the United States, the Tox21 strategy aims at shifting toxicological assessments away from traditional animal studies towards target-specific, mechanism-based and biological observations mainly obtained by using NAMs. Many other jurisdictions around the world are also increasing the use of NAMs. Hence, the provision of dedicated non-animal toxicological data and reporting formats as a basis for chemical risk assessment is necessary. Harmonising data reporting is crucial when aiming at re-using and sharing data for chemical risk assessment across jurisdictions. The OECD has developed a series of OECD Harmonised Templates (OHT), which are standard data formats designed for reporting information used for the risk assessment of chemicals relevant to their intrinsic properties, including effects on human health (e.g., toxicokinetics, skin sensitisation, repeated dose toxicity) and the environment (e.g., toxicity to test species and wildlife, biodegradation in soil, metabolism of residues in crops). The objective of this paper is to demonstrate the applicability of the OHT standard format for reporting information under various chemical risk assessment regimes, and to provide users with practical guidance on the use of OHT 201, in particular to report test results on intermediate effects and mechanistic information.

Environmental risk assessment of PPP application in European soils and potential ecosystem service losses considering impacts on non-target organisms.

The use of Plant Protection Products (PPPs) is leading to high exposure scenarios with potential risk to soil organisms, including non-target species. Assessment of the effects of PPPs on non-target organisms is one of the most important components of environmental risk assessment (ERA) since they play crucial functions in ecosystems, being main driving forces in different soil processes. As part of the framework, EFSA is proposing the use of the ecosystem services approach for setting specific protection goals. In fact, the services provided by soil organisms can be impacted by the misuse of PPPs in agroecosystems. The aim of this work was to assess PPPs potential risk upon ecosystem services along European soils, considering impacts on earthworms and collembola. Four well-known (2 insecticides-esfenvalerate and cyclaniliprole- and 2 fungicides - picoxystrobin and fenamidone-) worst case application (highest recommended application) were studied; exploring approaches for linked observed effects with impacts on ecosystem services, accounting for their mode of action (MoA), predicted exposure, time-course effects in Eisenia fetida and Folsomia sp. and landscape variability. The selected fungicides exerted more effects than insecticides on E. fetida, whereas few effects were reported for both pesticides regarding Folsomia sp. The most impacted ecosystem services after PPP application to crops appeared to be habitat provision, soil formation and retention, nutrient cycling, biodiversity, erosion regulation, soil remediation/waste treatment and pest and disease regulation. The main factors to be taken into account for a correct PPP use management in crops are discussed.

Linking pesticide marketing authorisations with environmental impact assessments through realistic landscape risk assessment paradigms.

Each year, the European Food Safety Authority, supported by a network of experts in the EU Member States, assesses and publishes the environmental risks of 30-40 pesticides active substances. The assessments support hundreds of national risk evaluations for marketing (re-)authorisations of Plant Protection Products. These prospective regulatory evaluations are based on worst-case scenarios in order to provide the high level of protection required by the EU legislations, and establishes the conditions for a correct use of the products including risk mitigations options. However, recent publications suggest that the desired high level of protection may not be achieved with the current risk assessment paradigm. The consideration of larger spatial scales and multiple stressors, including different pesticide uses, could improve the risk assessment process. A next step is the use of these larger spatial scales for evidence-based assessments, evaluating the overall impact of pesticide use on the European environment and biodiversity. Reaching this level would provide science-based support to the National Plans on sustainable use of pesticides and to the broader EU policies defined in the EU Environmental Action Programmes. Recent technological developments, as well as policy efforts, have solved two of the key issues blocking this progress in the past. Data availability and technical capacity for handling Big Data are no longer an unaffordable obstacle. The current proposal presents an alternative environmental risk assessment paradigm, integrating use patterns and pesticides properties with landscape ecotypes and eco-regions, covering the variability of the European agro-environmental conditions. The paradigm is suggested to be implemented in a spatially explicit conceptual model, using the ecosystem services approach and vulnerable key driver species to represent the service providing units. This approach would allow mapping the likelihood and magnitude of the impact of pesticide use on ecosystems functions, environmental resources, and biodiversity at the EU scale.

Glyphosate toxicity and carcinogenicity: a review of the scientific basis of the European Union assessment and its differences with IARC.

Glyphosate is the most widely used herbicide worldwide. It is a broad spectrum herbicide and its agricultural uses increased considerably after the development of glyphosate-resistant genetically modified (GM) varieties. Since glyphosate was introduced in 1974, all regulatory assessments have established that glyphosate has low hazard potential to mammals, however, the International Agency for Research on Cancer (IARC) concluded in March 2015 that it is probably carcinogenic. The IARC conclusion was not confirmed by the EU assessment or the recent joint WHO/FAO evaluation, both using additional evidence. Glyphosate is not the first topic of disagreement between IARC and regulatory evaluations, but has received greater attention. This review presents the scientific basis of the glyphosate health assessment conducted within the European Union (EU) renewal process, and explains the differences in the carcinogenicity assessment with IARC. Use of different data sets, particularly on long-term toxicity/carcinogenicity in rodents, could partially explain the divergent views; but methodological differences in the evaluation of the available evidence have been identified. The EU assessment did not identify a carcinogenicity hazard, revised the toxicological profile proposing new toxicological reference values, and conducted a risk assessment for some representatives uses. Two complementary exposure assessments, human-biomonitoring and food-residues-monitoring, suggests that actual exposure levels are below these reference values and do not represent a public concern.

Market analysis of the presence of endocrine disrupting chemicals in cosmetic products intended for oncological patients and other vulnerable groups.

There is growing concern about the presence of endocrine disrupting chemicals (EDCs) in cosmetics. We aimed to identify the main cosmetic ingredients with suspected endocrine-disrupting properties, and analyse their presence in current marketed products. Particular attention was given to products intended for susceptible (due to physiological status) and vulnerable (due to specific pathologies) groups with a view to informing cosmetologists and related health professionals of the scientific basis and current status of any concerns. Suspected EDCs used as cosmetic ingredients, included in lists published by regulatory agencies, were documented and investigated by weight of evidence analysis based on endocrine-related toxicity studies. In total, 49 suspected EDCs were identified from a sample of over a thousand cosmetic products marketed in the European Union. Suspected EDCs were found in approximately one third of products, with a similar frequency in products intended for susceptible and vulnerable groups. Avobenzone (CAS number:70356-09-1), octisalate (CAS number: 118-60-5), and butylated hydroxytoluene (CAS number: 128-37-0) were mostly commonly identified. The presence of EDCs was particularly high for sun care cosmetic products. Our results highlight potentially significant exposure through cosmetics to substances currently studied by regulatory institutions as suspected endocrine disrupters. EDCs are not yet universally regulated, and informing health professionals and educating the population as a precaution are options to reduce individual exposure levels, especially in vulnerable and susceptible groups. Special recommendations are needed for products intended for oncological patients.

Combination of toxicological and epidemiological approaches for estimating the health impact of atmospheric pollutants. A Proof of Concept for NO2.

BACKGROUND: Regular monitoring of the air pollutant nitrogen dioxide (NO2), an indicator for traffic-related emissions, is a priority in urban environments. The health impacts associated with NO2 exposure are the result of a combination of factors, including concentration, duration of exposure, and interactions with other pollutants. WHO has established air quality guidelines based on epidemiological studies. OBJECTIVE: This study develops a new concept "Health Impact Pathways (HIPs)" using adversity as a probabilistic indicator of health effects. For this purpose, it integrates available toxicological and epidemiological information, using Adverse Outcome Pathways (AOPs), in order to understand chemical-biological interactions and their consequences on health. METHODS: Literature review and meta-analysis of toxicological data supported by expert judgment were performed to establish: a) adversity pathways, b) quantitative criteria for scoring the observed toxicological effects (adversity indicators), c) NO2 exposure - adversity relationship for both long term (1 to 36 months) and short term (1 to 7 days). The NO2 daily concentrations from January 2001 to December 2022, were obtained from Madrid city Air Quality network monitoring database. Adversity levels were compared with relative risk levels for all-cause- and respiratory mortality estimated using linear equations from WHO 2021 guidelines. RESULTS: Non-linear relations were obtained for all long- and short-term NO2 related adversity indicators; for long-term effects, the best fitting was obtained with a modified Haber's law model with an exponential coefficient for the exposure time of 0.25. Estimations are presented for a set of case studies for Madrid city, covering temporal and spatial variability. A clear improvement trend along the two decades was observed, as well as high inter- and intra-station variability; the adversity indicators provided integrated information on the temporal and spatial evolution of population level risk. DISCUSSION: The proposed HIP conceptual approach offers promising advances for integrating experimental and epidemiological data. The next step is linking the concentration-adversity relationship with population health impacts through probability estimations, the preliminary estimations confirm the need for assessing independently different population groups.

Trust your gut: Establishing confidence in gastrointestinal models - An overview of the state of the science and contexts of use.

The webinar series and workshop titled "Trust Your Gut: Establishing Confidence in Gastrointestinal Models ­ An Overview of the State of the Science and Contexts of Use" was co-organized by NICEATM, NIEHS, FDA, EPA, CPSC, DoD, and the Johns Hopkins Center for Alternatives to Animal Testing (CAAT) and hosted at the National Institutes of Health in Bethesda, MD, USA on October 11-12, 2023. New approach methods (NAMs) for assessing issues of gastrointestinal tract (GIT)- related toxicity offer promise in addressing some of the limitations associated with animal-based assessments. GIT NAMs vary in complexity, from two-dimensional monolayer cell line-based systems to sophisticated 3-dimensional organoid systems derived from human primary cells. Despite advances in GIT NAMs, challenges remain in fully replicating the complex interactions and pro­cesses occurring within the human GIT. Presentations and discussions addressed regulatory needs, challenges, and innovations in incorporating NAMs into risk assessment frameworks; explored the state of the science in using NAMs for evaluating systemic toxicity, understanding absorption and pharmacokinetics, evaluating GIT toxicity, and assessing potential allergenicity; and discussed strengths, limitations, and data gaps of GIT NAMs as well as steps needed to establish confidence in these models for use in the regulatory setting.

Non-animal methods to assess whether chemicals may be toxic to the human digestive tract promise to complement or improve on animal-based methods. These approaches, which are based on human or animal cells and/or computer models, are faced with their own technical challenges and need to be shown to predict adverse effects in humans. Regulators are tasked with evaluating submitted data to best protect human health and the environment. A webinar series and workshop brought together scientists from academia, industry, military, and regulatory authorities from dif­ferent countries to discuss how non-animal methods can be integrated into the risk assessment of drugs, food additives, dietary supplements, pesticides, and industrial chemicals for gastrointestinal toxicity.

Applicability of Food Monitoring Data for Assessing Relative Exposure Contributions of Pyrethroids in Retrospective Human Biomonitoring Risk Estimations.

The use of pyrethroids is very broad and shows increasing trends. Human biomonitoring studies represent the best approach for realistic risk estimations, but their interpretation requires a tiered approach. A previous HBM4EU study indicated levels in European children groups just around the threshold for concern, requiring further refinement. The main difficulty is that several pyrethroids with different toxicity potencies generate the same urinary metabolites. As diet is the main pyrethroid source for the general population, EU food monitoring data reported by EFSA have been used to estimate the relative contribution of each pyrethroid. The main contributors were cypermethrin for DCCA and 3-PBA and lambda-cyhalothrin for CFMP. Urinary levels predicted from food concentration according to the EFSA diets were mostly within the range of measured levels, except 3-PBA and CFMP levels in children, both below measured levels. The predicted lower levels for 3-PBA can be explained by the very low Fue value, initially proposed as conservative, but that seems to be unrealistic. The discrepancies for CFMP are mostly for the highest percentiles and require further assessments. The refined assessments included the revision of the previously proposed human biomonitoring guidance values for the general population, HBM-GV Gen Pop, following recent toxicological reevaluations, and the estimation of hazard quotients (HQs) for each individual pyrethroid and for the combined exposure to all pyrethroids. All HQs were below 1, indicating no immediate concern, but attention is required, particularly for children, with HQs in the range of 0.2-0.3 for the highly exposed group. The application of probabilistic methods offers assessments at the population level, addressing the variability in exposure and risk and providing relevant information for Public Health impact assessments and risk management prioritization.

The use of new approach methodologies for the environmental risk assessment of food and feed chemicals.

New Approach Methodologies (NAMs) provide tools for supporting both human and environmental risk assessment (HRA and ERA). This short review provides recent insights regarding the use of NAMs in ERA of food and feed chemicals. We highlight the usefulness of tiered methods supporting weight-of-evidence approaches in relation to problem formulation (i.e., data availability, time, and resource availability). In silico models, including quantitative structure activity relationship models, support filling data gaps when no chemical property or ecotoxicological data are available, and biologically-based models (e.g., toxicokinetic-toxicodynamic models, dynamic energy models, physiologically-based models and species sensitivity distributions) are applicable in more data rich situations, including landscape-based modelling approaches. Particular attention is given to provide practical examples to apply the approaches described in real-world settings. We conclude with future perspectives, with regards to the need for addressing complex challenges such as chemical mixtures and multiple stressors in a wide range of organisms and ecosystems.

Risk Assessment of Combined Exposure to Multiple Chemicals at the European Food Safety Authority: Principles, Guidance Documents, Applications and Future Challenges.

Human health and animal health risk assessment of combined exposure to multiple chemicals use the same steps as single-substance risk assessment, namely problem formulation, exposure assessment, hazard assessment and risk characterisation. The main unique feature of combined RA is the assessment of combined exposure, toxicity and risk. Recently, the Scientific Committee of the European Food Safety Authority (EFSA) published two relevant guidance documents. The first one "Harmonised methodologies for the human health, animal health and ecological risk assessment of combined exposure to multiple chemicals" provides principles and explores methodologies for all steps of risk assessment together with a reporting table. This guidance supports also the default assumption that dose addition is applied for combined toxicity of the chemicals unless evidence for response addition or interactions (antagonism or synergism) is available. The second guidance document provides an account of the scientific criteria to group chemicals in assessment groups using hazard-driven criteria and prioritisation methods, i.e., exposure-driven and risk-based approaches. This manuscript describes such principles, provides a brief description of EFSA's guidance documents, examples of applications in the human health and animal health area and concludes with a discussion on future challenges in this field.

TKPlate 1.0: An Open-access platform for toxicokinetic and toxicodynamic modelling of chemicals to implement new approach methodologies in chemical risk assessment.

This publication is linked to the following EFSA Supporting Publications articles: http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2023.EN-8441/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2023.EN-8440/full, http://onlinelibrary.wiley.com/doi/10.2903/sp.efsa.2023.EN-8437/full.

How to use human biomonitoring in chemical risk assessment: Methodological aspects, recommendations, and lessons learned from HBM4EU.

One of the aims of the European Human Biomonitoring Initiative, HBM4EU, was to provide examples of and good practices for the effective use of human biomonitoring (HBM) data in human health risk assessment (RA). The need for such information is pressing, as previous research has indicated that regulatory risk assessors generally lack knowledge and experience of the use of HBM data in RA. By recognising this gap in expertise, as well as the added value of incorporating HBM data into RA, this paper aims to support the integration of HBM into regulatory RA. Based on the work of the HBM4EU, we provide examples of different approaches to including HBM in RA and in estimations of the environmental burden of disease (EBoD), the benefits and pitfalls involved, information on the important methodological aspects to consider, and recommendations on how to overcome obstacles. The examples are derived from RAs or EBoD estimations made under the HBM4EU for the following HBM4EU priority substances: acrylamide, o-toluidine of the aniline family, aprotic solvents, arsenic, bisphenols, cadmium, diisocyanates, flame retardants, hexavalent chromium [Cr(VI)], lead, mercury, mixture of per-/poly-fluorinated compounds, mixture of pesticides, mixture of phthalates, mycotoxins, polycyclic aromatic hydrocarbons (PAHs), and the UV-filter benzophenone-3. Although the RA and EBoD work presented here is not intended to have direct regulatory implications, the results can be useful for raising awareness of possibly needed policy actions, as newly generated HBM data from HBM4EU on the current exposure of the EU population has been used in many RAs and EBoD estimations.

Construction of a predictive model for concentration of nickel and vanadium in vacuum residues of crude oils using artificial neural networks and LIBS.

A predictive model to determine the concentration of nickel and vanadium in vacuum residues of Colombian crude oils using laser-induced breakdown spectroscopy (LIBS) and artificial neural networks (ANNs) with nodes distributed in multiple layers (multilayer perceptron) is presented. ANN inputs are intensity values in the vicinity of the emission lines 300.248, 301.200 and 305.081 nm of the Ni(I), and 309.310, 310.229, and 311.070 nm of the V(II). The effects of varying number of nodes and the initial weights and biases in the ANNs were systematically explored. Average relative error of calibration/prediction (REC/REP) and average relative standard deviation (RSD) metrics were used to evaluate the performance of the ANN in the prediction of concentrations of two elements studied here.

Are fish and standardized FETAX assays protective enough for amphibians? A case study on Xenopus laevis larvae assay with biologically active substances present in livestock wastes.

Biologically active substances could reach the aquatic compartment when livestock wastes are considered for recycling. Recently, the standardized FETAX assay has been questioned, and some researchers have considered that the risk assessment performed on fish could not be protective enough to cover amphibians. In the present study a Xenopus laevis acute assay was developed in order to compare the sensitivity of larvae relative to fish or FETAX assays; veterinary medicines (ivermectin, oxytetracycline, tetracycline, sulfamethoxazole, and trimethoprim) and essential metals (zinc, copper, manganese, and selenium) that may be found in livestock wastes were used for the larvae exposure. Lethal (LC(50)) and sublethal effects were estimated. Available data in both, fish and FETAX studies, were in general more protective than values found out in the current study, but not in all cases. Moreover, the presence of nonlethal effects, caused by ivermectin, zinc, and copper, suggested that several physiological mechanisms could be affected. Thus, this kind of effects should be deeply investigated. The results obtained in the present study could expand the information about micropollutants from livestock wastes on amphibians.

Predicting environmental concentrations and the potential risk of Plant Protection Products (PPP) on non-target soil organisms accounting for regional and landscape ecological variability in european soils.

Plant Protection Products (PPP) raise concerns as their application may cause effects on some soil organisms considered non-target species which could be highly sensitive to some pesticides. The European Food and Safety Authority (EFSA), in collaboration with the Joint Research Centre (JRC) of the European Commission, has developed guidance and a software tool, Persistence in Soil Analytical Model (PERSAM), for conducting soil exposure assessments. EFSA PPR Panel has published recommendations for the risk assessment of non-target soil organisms. We have used PERSAM for calculating PPPs predicted environmental concentrations (PECs); and used the estimated PEC for assessing potential risks using Toxicity Exposure Ratios (TER) for selected soil organisms and good agricultural practices. Soil characteristics and environmental variables change along a latitudinal axis through the European continent, influencing the availability of PPP, their toxicity upon soil biota, and hence, impacting on the risk characterization. Although PERSAM includes as input geographical information, the information is aggregated and not further detailed in the model outputs. Therefore, there is a need to develop landscape based environmental risk assessment methods addressing regional variability. The objective was to integrate spatially explicit exposure (PECs) and effect data (biological endpoints i.e. LC50, NOEC, etc.) to estimate the risk quotient (TER) of four PPP active substances (esfenvalerate, cyclaniliprole, picoxystrobin, fenamidone) on non-target species accounting European landscape and agricultural variability. The study was focused on the effects produced by the above-mentioned pesticides on two soil organisms: E. fetida earthworms and Folsomia sp. collembolans. After running PERSAM assuming a worst case application of PPPs, PECs in total soil and pore water were obtained for different depths in northern, central and southern European soils. With this data, soil variability and climatic differences among soils divided in three large Euroregions along a latitudinal transect (Northern, Central, Southern Europe) were analysed. Summarising, a trend to accumulate higher PECs and TERs in total soil was observed in the north decreasing towards the south. Higher PECs and TERs could be expected in pore water in southern soils, decreasing towards the north. The risk disparity between pollutant concentrations at different soils compartments should be taken into account for regulatory purposes, as well as the potential landscape variabilities among different Euroregions.

MIR-203A-3P AND MMP-2 PROTEINS ARE HIGHLY EXPRESSED IN CIRCULATING TUMOR CELLS FROM PATIENTS WITH PANCREATIC CARCINOMA. / PROTEÍNAS MIR-203A-3P E MMP-2 SÃO ALTAMENTE EXPRESSAS EM CÉLULAS TUMORAIS CIRCULANTES DE PACIENTES COM CARCINOMA PANCREÁTICO.

OBJECTIVES: Ductal adenocarcinoma of the pancreas is the fourth most common cancer-associated cause of death in the Western world. The presence of circulating tumor cells (CTCs) can be considered a potential prognostic factor, as these cells represent tumor progression, allowing monitoring of therapeutic efficacy. The objectives of this study were to explore the morphological, molecular, and phenotypic characteristics of CTCs from the blood of patients with pancreatic carcinoma and to correlate the findings with response to treatment, progression-free survival, overall survival (OS), and deep vein thrombosis (DVT). METHODS: Peripheral blood (10 mL) was analyzed before the beginning of treatment after 60 and 120 days. CTCs were detected by using ISET® and characterized by immunocytochemistry. For microRNAs (miRNAs) analysis, peripheral leukocytes from the same patients and healthy individuals (controls) were collected in parallel at baseline. The expression of miRNAs was evaluated (in pool) using TaqMan® Array Human MicroRNA Cards v2.0. RESULTS: Only nine patients were included. The proteins, namely, matrix metalloproteinase-2 (MMP2) and TGFß-RI, were highly expressed (77.7%) in CTCs at baseline; at the first follow-up, MMP2 was predominant (80%) and, at the second follow-up, MMP2 and vimentin were predominant (50%). Circulating tumor microemboli (CTMs) were found in two patients and both presented DVT. The miR-203a-3p was highly expressed in CTCs. The miR-203a-3p is involved in the stimulation of epithelial-to-mesenchymal transition (EMT) and is related to worse OS in pancreatic cancer (TCGA data). CONCLUSION: Due to the low number of patients and short follow-up, we did not observe a correlation between CTCs and response to treatment. However, there was a correlation between CTM and DVT and also miR-203a-3p was highly expressed in CTCs, corroborating the findings of EMT proteins. This study opens the perspectives concerning the dynamic change in the pattern of proteins expressed along with treatment and the use of miRNAs as new targets in pancreatic carcinoma.

OBJETIVOS: O adenocarcinoma ductal do pâncreas é a quarta causa de morte associada ao câncer mais comum no mundo ocidental. A presença de células tumorais circulantes (CTCs) pode ser considerada um potencial fator prognóstico, visto que essas células representam a progressão tumoral, permitindo o monitoramento da eficácia terapêutica. explorar as características morfológicas, moleculares e fenotípicas das células tumorais circulantes (CTCs) do sangue de pacientes com carcinoma pancreático e correlacionar os achados com a resposta ao tratamento, sobrevida livre de progressão, sobrevida global (SG) e trombose venosa profunda (TVP). MÉTODOS: o sangue periférico (10mL) foi analisado antes do início do tratamento e após 60 e 120 dias. As CTCs foram detectadas pelo ISET® e caracterizadas por imunocitoquímica. Para análise de miRNAs, leucócitos periféricos dos mesmos pacientes e indivíduos saudáveis foram coletados em paralelo no início do estudo. A expressão de miRNAs foi avaliada usando TaqMan T Array Human MicroRNA Cards v2.0. RESULTADOS: foram incluídos 9 pacientes. As proteínas MMP2 e TGFß-RI foram altamente expressas (77,7%) nas CTCs no início do estudo. No primeiro acompanhamento, MMP2 era predominante (80%) e no segundo acompanhamento, MMP2 e vimentina eram predominantes (50%). Microêmbolos tumorais circulantes (MTC) foram encontrados em dois pacientes e ambos apresentavam TVP. O miR-203a-3p foi altamente expresso em CTCs. miR-203a-3p está envolvido na estimulação da transição epitelio-mesenquima (TEM) e relacionado a pior SG no câncer pancreático (dados TCGA). CONCLUSÃO: Devido ao baixo número de pacientes e curto seguimento, não observamos correlação entre CTCs e resposta ao tratamento. No entanto, houve uma correlação entre MTC e TVP. Além disso, miR-203a-3p foi altamente expresso em CTCs, corroborando os achados de proteínas EMT. Este estudo abre perspectivas sobre a mudança dinâmica no padrão de proteínas expressas ao longo do tratamento e a utilização de miRNAs como novos alvos no carcinoma pancreático.

In Silico Methods for Environmental Risk Assessment: Principles, Tiered Approaches, Applications, and Future Perspectives.

This chapter aims to introduce the reader to the basic principles of environmental risk assessment of chemicals and highlights the usefulness of tiered approaches within weight of evidence approaches in relation to problem formulation i.e., data availability, time and resource availability. In silico models are then introduced and include quantitative structure-activity relationship (QSAR) models, which support filling data gaps when no chemical property or ecotoxicological data are available. In addition, biologically-based models can be applied in more data rich situations and these include generic or species-specific models such as toxicokinetic-toxicodynamic models, dynamic energy budget models, physiologically based models, and models for ecosystem hazard assessment i.e. species sensitivity distributions and ultimately for landscape assessment i.e. landscape-based modeling approaches. Throughout this chapter, particular attention is given to provide practical examples supporting the application of such in silico models in real-world settings. Future perspectives are discussed to address environmental risk assessment in a more holistic manner particularly for relevant complex questions, such as the risk assessment of multiple stressors and the development of harmonized approaches to ultimately quantify the relative contribution and impact of single chemicals, multiple chemicals and multiple stressors on living organisms.

Improving the Risk Assessment of Pesticides through the Integration of Human Biomonitoring and Food Monitoring Data: A Case Study for Chlorpyrifos.

The risk assessment of pesticide residues in food is a key priority in the area of food safety. Most jurisdictions have implemented pre-marketing authorization processes, which are supported by prospective risk assessments. These prospective assessments estimate the expected residue levels in food combining results from residue trials, resembling the pesticide use patterns, with food consumption patterns, according to internationally agreed procedures. In addition, jurisdictions such as the European Union (EU) have implemented large monitoring programs, measuring actual pesticide residue levels in food, and are supporting large-scale human biomonitoring programs for confirming the actual exposure levels and potential risk for consumers. The organophosphate insecticide chlorpyrifos offers an interesting case study, as in the last decade, its acceptable daily intake (ADI) has been reduced several times following risk assessments by the European Food Safety Authority (EFSA). This process has been linked to significant reductions in the use authorized in the EU, reducing consumers' exposure progressively, until the final ban in 2020, accompanied by setting all EU maximum residue levels (MRL) in food at the default value of 0.01 mg/kg. We present a comparison of estimates of the consumer's internal exposure to chlorpyrifos based on the urinary marker 3,5,6-trichloro-2-pyridinol (TCPy), using two sources of monitoring data: monitoring of the food chain from the EU program and biomonitoring of European citizens from the HB4EU project, supported by a literature search. Both methods confirmed a drastic reduction in exposure levels from 2016 onwards. The margin of exposure approach is then used for conducting retrospective risk assessments at different time points, considering the evolution of our understanding of chlorpyrifos toxicity, as well as of exposure levels in EU consumers following the regulatory decisions. Concerns are presented using a color code, and have been identified for almost all studies, particularly for the highest exposed group, but at different levels, reaching the maximum level, red code, for children in Cyprus and Israel. The assessment uncertainties are highlighted and integrated in the identification of levels of concern.