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Anticoagulant rodenticides (ARs) are potent pesticides acting as vitamin K epoxide reductase inhibitors causing haemorrhaging or external bleeding from orifices and/or skin lesions in intoxicated rodents. However, their non-selective mode of action makes them particularly harmful for non-target wildlife, which may be exposed to ARs via ingestion of AR-containing baits (primary exposure), feeding on AR-intoxicated rodents and carrions (secondary exposure), consuming AR-contaminated necrophagous species (tertiary exposure), and exposure to surface waters receiving baited sewer systems and ARs from outdoor-placed traps after heavy rain events. In the present study, we assessed the suitability of hairs as a non-invasive matrix for monitoring the possible exposure of mammals to ARs with a focus on the first-generation anticoagulant rodenticides (FGARs) warfarin, coumatetralyl, and chlorophacinone and the second-generation anticoagulant rodenticides (SGARs) brodifacoum, bromadiolone, difenacoum, flocoumafen, and difethialone. The Red fox (n = 24) was selected as the species representing the potentially exposed non-target wildlife in a littoral area of Northern Italy along the Adriatic coast (Cavallino-Treporti municipality). Half (n = 12) of the analysed hair samples were positive for at least one of the targeted ARs, with a higher prevalence of SGARs (n = 11; 46%) compared to FGARs (n = 1; 4%). The most frequently quantified ARs were brodifacoum (25%), difethialone (13%), and flocoumafen (13%), with concentrations ranging from 0.08 ng g -1 (difethialone) to 0.96 ng g -1 (brodifacoum). These data documented that a relevant part of the Red foxes living in the study area were exposed to ARs and, most importantly, provided the first evidence that hair residues can be used as a non-invasive matrix for assessing the possible exposure of mammals to ARs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The uptake and translocation of four polybrominated diphenyl ethers (PBDEs) and four novel brominated flame retardants (NBFRs) in tomato plants (Solanum lycopersicum L.) were investigated via the RHIZOtest, a standard soil-based biotest, optimized for organic compounds. Tomato plants were exposed to soil samples spiked with 0 (i.e. control), 5.00 or 50.00 ng g -1 dw of each compound. Compared of those of the control, exposure to increasing spiking concentrations resulted in average reductions of 13% and 26% (w/w) in tomato plant biomass. Higher concentrations of NBFRs were analyzed both in roots, ranging from 0.23 to 8.01 ng g -1 dw for PBDEs and from 1.25 to 18.51 ng g -1 dw for NBFRs, and in shoots, ranging from 0.09 to 5.58 ng g -1 dw and from 0.47 to 7.78 ng g -1 dw for PBDEs and NBFRs, respectively. This corresponded to an average soil uptake of 5% for PBDEs and 9% for NBFRs at the lower soil-spiking level, and 3% for PBDEs and 6% for NBFRs at the higher soil spiking level. Consequently, among both initial spiking levels, the soil-root concentration factor (RCF) values were lower on average for PBDEs (0.13 ± 0.05 g dw soil g -1 dw roots) than for NBFRs (0.33 ± 0.16 g dw soil g -1 dw roots). Conversely, nondifferent values of the root-shoot transfer factor (TF) were calculated for both PBDEs (0.54 ± 0.13 g dw roots g -1 dw shoots) and NBFRs (0.49 ± 0.24 g dw roots g -1 dw shoots). The differences and similarities reported in the RCF and TF between and within the two groups of compounds can be explained by their properties. The calculated RCF and TF values of the PBDEs exhibited a decreasing trend as the number of bromine atoms increased. Additionally, a robust negative linear correlation was observed between RCF values and the respective logK ow values for the PBDEs, at both soil-spiking levels. The root uptake of NBFRs exhibited a negative correlation with their hydrophobicity; however, this was not observed in the context of root-to-shoot transfer. The presence of a second aromatic ring appears to be the key factor influencing the observed variations in NBFRs, with biphenyl NBFRs (BTBPE and DBDPE) characterized by lower uptake and reduced translocation potential than monophenyl PBEB and HBB. Understanding the transfer of these compounds to crops, especially near plastic recycling waste sites, is crucial for understanding the risks of their potential inclusion in the human food chain., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Per- and polyfluoroalkyl substances (PFAS) constitute a heterogeneous group of synthetic compounds widely used in industrial applications. The estimation of PFAS half-life (t 1/2 ) is essential to quantify their persistence, their toxicity and mechanism of action in humans., Objectives: The purpose of this review is to summarize the evidence on PFAS half-lives in humans from the available literature, and to investigate the limitations and uncertainties characterizing half-life estimation., Methods: The search was conducted on PubMed, Scopus, and Embase databases up to July 03, 2023 and was aimed at identifying all papers that estimated PFAS half-life in human populations. We excluded studies on temporal trends or providing estimates of half-life based solely on renal clearance. As persistent and ongoing exposures can influence half-life estimation, we decided to include only studies that were conducted after the main source of exposure to PFAS had ceased. A random-effects meta-analysis was conducted on studies that reported perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS) or perfluorohexanesulfonic acid (PFHxS) half-life estimation. Risk of bias was evaluated using the OHAT tool., Results: A total of 13 articles were included in the review, with 5 studies conducted in exposed general populations and 8 studies conducted in exposed workers; the estimated mean half-life ranged from 1.48 to 5.1 years for PFOA, from 3.4 to 5.7 years for total PFOS, and from 2.84 to 8.5 years for PFHxS. High heterogeneity among studies was observed; potential reasons include the variability among the investigated populations, discrepancies in considering ongoing exposures, variability in PFAS isomeric compositions, accounting for background exposure, time since exposure stopped and methods used for half-life estimation., Discussion: Despite the efforts made to better understand PFAS toxicokinetics, further studies are needed to identify important characteristics of these persistent chemicals. Biomonitoring studies should focus on persistent and unaccounted sources of exposure to PFAS and on individual characteristics potentially determining half-life, to ensure accurate estimates., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Inc.)