Human urinary arsenic species, associated exposure determinants and potential health risks assessed in the HBM4EU Aligned Studies

The European Joint Programme HBM4EU coordinated and advanced human biomonitoring (HBM) in Europe in order to provide science-based evidence for chemical policy development and improve chemical management. Arsenic (As) was selected as a priority substance under the HBM4EU initiative for which open, policy relevant questions like the status of exposure had to be answered. Internal exposure to inorganic arsenic (iAs), measured as Toxic Relevant Arsenic (TRA) (the sum of As(III), As(V), MMA, DMA) in urine samples of teenagers differed among the sampling sites (BEA (Spain) > Riksmaten adolescents (Sweden), ESTEBAN (France) > FLEHS IV (Belgium), SLO CRP (Slovenia)) with geometric means between 3.84 and 8.47 μg/L. The ratio TRA to TRA + arsenobetaine or the ratio TRA to total arsenic varied between 0.22 and 0.49. Main exposure determinants for TRA were the consumption of rice and seafood. When all studies were combined, Pearson correlation analysis showed significant associations between all considered As species. Higher concentrations of DMA, quantitatively a major constituent of TRA, were found with increasing arsenobetaine concentrations, a marker for organic As intake, e.g. through seafood, indicating that other sources of DMA than metabolism of inorganic As exist, e.g. direct intake of DMA or via the intake of arsenosugars or -lipids. Given the lower toxicity of DMA(V) versus iAs, estimating the amount of DMA not originating from iAs, or normalizing TRA for arsenobetaine intake could be useful for estimating iAs exposure and risk. Comparing urinary TRA concentrations with formerly derived biomonitoring equivalent (BE) for non-carcinogenic effects (6.4 μg/L) clearly shows that all 95th percentile exposure values in the different studies exceeded this BE. This together with the fact that cancer risk may not be excluded even at lower iAs levels, suggests a possible health concern for the general population of Europe.HBM4EU is co-financed under Horizon 2020 (grant agreement No 733032). The authors thank all investigators of the contributing studies for their participation and contribution to the joint HBM4EU survey and the national programme owners for their financial support. Also thanks to the participating teenagers and their families, the field workers that collected the samples. The FLEHS IV study was conducted within the framework of the Flemish Center of Expertise on Environment and Health (FLEHS 2016–2020) and funded by the Flemish Government, Department of Environment & Spatial Development. We thank the teenagers and their families that participated in the study, the field workers from the Pro vincial Institute of Hygiene and VITO for the sample and data collection. All collaborators of the scientific teams of the Flemish Center of Expertise on Environment and Health (https://www.milieu-en-gezondheid.be/en/about-the-center-0) and Karen Van Campenhout and Caroline Teughels from the Flemish Department of Environment & Spatial Development for their valuable input in the field work committee. The funding of the German Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection is gratefully acknowledged. BEA study was co-funded by the Spanish Ministry of Agriculture, Fisheries and Food and the Insituto de Salud Carlos III (SEG 1321/15). In Slovenia the work was cofounded by the Slovenian Research Funding Agency – ARRS through a research programme P-0143. ESTEBAN was Funded by Sant´e Publique France and the French ministries of Health and the Environment. The study of RIKSMATEN was conducted and mainly financed by the Swedish Food Agency. Financial support was provided from the Swedish Civil Contingencies Agency and from the Swedish Environmental Pro tection Agency (SEPA).S

Harmonized human biomonitoring in European children, teenagers and adults: EU-wide exposure data of 11 chemical substance groups from the HBM4EU Aligned Studies (2014–2021)

HBM4EU is co-financed under Horizon 2020 (grant agreement No 733032).As one of the core elements of the European Human Biomonitoring Initiative (HBM4EU) a human biomonitoring (HBM) survey was conducted in 23 countries to generate EU-wide comparable HBM data. This survey has built on existing HBM capacity in Europe by aligning national or regional HBM studies, referred to as the HBM4EU Aligned Studies. The HBM4EU Aligned Studies included a total of 10,795 participants from three age groups: (i) 3,576 children aged 6-12 years, (ii) 3,117 teenagers aged 12-18 years, and (iii) 4,102 young adults aged 20-39 years. The participants were recruited between 2014 and 2021 in 11-12 countries per age group, geographically distributed across Europe. Depending on the age group, internal exposure to phthalates and the substitute DINCH, halogenated and organophosphorus flame retardants, per- and polyfluoroalkyl substances (PFASs), cadmium, bisphenols, polycyclic aromatic hydrocarbons (PAHs), arsenic species, acrylamide, mycotoxins (deoxynivalenol (total DON)), benzophenones and selected pesticides was assessed by measuring substance specific biomarkers subjected to stringent quality control programs for chemical analysis. For substance groups analyzed in different age groups higher average exposure levels were observed in the youngest age group, i.e., phthalates/DINCH in children versus teenagers, acrylamide and pesticides in children versus adults, and benzophenones in teenagers versus adults. Many biomarkers in teenagers and adults varied significantly according to educational attainment, with higher exposure levels of bisphenols, phthalates, benzophenones, PAHs, and acrylamide in participants (from households) with lower educational attainment, while teenagers from households with higher educational attainment have higher exposure levels for PFASs and arsenic. In children, a social gradient was only observed for the non-specific pyrethroid metabolite 3-PBA and di-isodecyl phthalate (DiDP), with higher levels in children from households with higher educational attainment. Geographical variations were seen for all exposure biomarkers. For 15 biomarkers, the available health-based HBM guidance values were exceeded with the highest exceedance rates for toxicologically relevant arsenic in teenagers (40%), 3-PBA in children (36%), and between 11 and 14% for total DON, Σ (PFOA + PFNA + PFHxS + PFOS), bisphenol S and cadmium. The infrastructure and harmonized approach succeeded in obtaining comparable European-wide internal exposure data for a prioritized set of 11 chemical groups. These data serve as a reference for comparison at the global level, provide a baseline to compare the efficacy of the European Commission's chemical strategy for sustainability, and will give leverage to national policymakers for the implementation of targeted measures.info:eu-repo/semantics/publishedVersio

Comparative effects of arsenite (As(III)) and arsenate (As(V)) on whole plants and cell lines of the arsenic-resistant halophyte plant species Atriplex atacamensis

Whole plants and hypocotyl-derived calli of the halophyte plant species Atriplex atacamensiswere exposed to 50 μMarsenate (As(V))or 50 μMarsenite (As(III)). At thewhole plant level,As(III) wasmore toxic thanAs(V): it reduced plant growth, stomatal conductance,photosystem II efficiency while As(V) did not. In roots, As accumulated to higher level in response toAs(III) than in response to As(V). Within root tissues, both arsenate and arsenite were identified in response to each treatment suggesting that oxidation of As(III) may occur. More than 40% of As was bound to the cell wall in the roots of As(V)-treated plants while this proportion strongly decreased in As(III)-treated ones. In leaves, total As and the proportion of As bound to the cell wall were similar in response to As(V) and As(III). Non-protein thiol increased to higher extent in response to As(V) than in response to As(III) while ethylene synthesis was increased in As(III)-treated plants only. Polyamine profile was modified in a contrasting way in response to As(V) and As(III). At the callus level, As(V) and As(III) 50 μMdid not reduce growth despite an important As accumulation within tissues. Calli exposed to 50 μMAs did not increase the endogenous non-protein thiol. In contrast to the whole plants, arsenite was not more toxic than arsenate at the cell line level and As(V)-treated calli produced higher amounts of ethylene and malondialdehyde. A very high dose of As(V) (1000 μM) strongly reduced callus growth and lead to non-protein thiols accumulation. It is concluded that As(III) was more toxic than As(V) at the plant level but not at the cellular level and that differential toxicitywas not fully explained by speciation of accumulated As. Arsenic resistance in A. atacamensis exhibited a cellular componentwhich however did not reflect the behavior of whole plant when exposed to As(V) or As(III)

Impact of iron plaque on arsenic uptake and speciation in rice (Oryza sativa L.) along plant development.

Rice (Oryza sativa) is a staple crop for over half of the world’s population. In numerous areas of South and South-east Asia, soils and aquifers are arsenic contaminated leading to a potential health risk to populations due to As accumulation in rice. In most As-affected areas of South and South-east Asia, groundwater is rich in iron. Excess of both elements are serious threat to sustainable agriculture, in relation to a decrease of rice yield and a contamination of rice grains by toxic As. Nevertheless, the ability of rice species to carry oxygen from the air down its stem through aerenchyma and discharge it through its roots, creates an oxidised zone around individual roots in which Fe is oxidised to the Fe(III) state and forms a coating called “iron plaque”. This Fe plaque may retain As and reduces it disponibility for the plant. We aimed to investigate the impact of combined As and Fe stresses on rice growth and yield and study the influence of the Fe plaque on As uptake and speciation. Twenty five days old rice seedlings were exposed to As (V) (50mM and 100mM), Fe(II) (125 ppm) or combined treatments until plant maturation. The presence of Fe allowed the development of a Fe plaque on the rice roots that limited the As accumulation and modified its speciation in the different plant organs. Combined stresses also significantly reduced the plant yield and affected plant nutrition

Effects of simultaneous arsenic and iron toxicities on rice (Oryza sativa L.) development, yield-related parameters and As and Fe accumulation in relation to As speciation in the grains

Background and aim In numerous areas, rice cultivated under flooded conditions is exposed simultaneously to iron excess and arsenic contamination. The impact of these combined stresses on yield-related parameters and As distribution and speciation in various plant parts remains poorly documented. Methods Rice (cv I Kong Pao) was exposed to iron excess (125 mgL−1 Fe2SO4), arsenic (50 and 100 μM Na2HAsO4.7H2O) or a combination of those stressing agents in hydroponic culture until harvest. Plant growth, yield-related parameters, non protein thiols concentration and mineral nutrition were studied in roots and shoots. Arsenic speciation was determined by high-performance liquid chromatography-hydride generation-atomic fluorescence spectrometry. Key Results Iron excess increased As retention by the roots in relation to the development of the root iron plaque but decreased As accumulation in the shoot. Arsenic concentration was lower in the grains than in the shoots. Iron stress reduced As accumulation in the husk but not in the dehusked grains. Iron excess decreased the proportion of extractable As(III) and As (V) in the grain while it increased the proportion of extractable As(III) in the shoot. Combined stresses (Fe+As) affected plant nutrition and significantly reduced the plant yield by limiting the number of grains per plant and the grain filling. Conclusions Fe excess had an antagonist impact on shoot As concentration but an additive negative impact on several yield-related parameters. Iron stress influences both As distribution and As speciation in rice

Bioaccumulation of Arsenic Species in Rays from the Northern Adriatic Sea

The difference in arsenic concentration and speciation between benthic (Pteromylaeus bovinus, Myliobatis aquila) and pelagic rays (Pteroplatytrygon violacea) from the northern Adriatic Sea (Gulf of Trieste) in relation to their size (age) was investigated. High arsenic concentrations were found in both groups with tendency of more efficient arsenic accumulation in benthic species, particularly in muscle (32.4 to 362 µg·g−1 of total arsenic). This was attributed to species differences in arsenic access, uptake and retention. In liver most arsenic was present in a form of arsenobetaine, dimethylarsinic acid and arsenoipids, whereas in muscle mainly arsenobetaine was found. The good correlations between total arsenic/arsenobetaine and size reflect the importance of accumulation of arsenobetaine with age. Arsenobetaine is an analogue of glycine betaine, a known osmoregulator in marine animals and both are very abundant in mussels, representing an important source of food for benthic species P. bovinus and M. aquila