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1.
Environ Pollut ; 350: 124050, 2024 Jun 01.
Article En | MEDLINE | ID: mdl-38677454

Identifying the sources of polycyclic aromatic hydrocarbons (PAHs) in complex environmental matrices is essential for understanding the impact of combustion-related human activities on the environment. Since the turn of the century, advances in analytical capability and accuracy of accelerator mass spectrometry (AMS) have made it possible to accurately determine the source apportionment of PAHs based on their radiocarbon (14C) mass conservation. This also allows us to trace the environmental transport processes of PAHs from the perspective of molecular 14C. However, natural environmental matrices have very low concentrations of PAHs (ppb to ppm level). To meet the requirements of carbon weight for 14C measurement by AMS, trace PAHs in complex environmental matrices must be enriched thousands of times, and then higher purity individual PAH molecules should be obtained through a series of complex purification procedures. Therefore, the technical difficulty is the main challenge in expanding the application of compound-specific 14C analysis in environmental science. This article reviews the detailed pretreatment procedures for 14C measurement of specific PAHs, including sample enrichment, extraction and purification of aromatic components, preparation of compound-specific PAHs by preparative capillary gas chromatography, graphitization of samples with ultra-small carbon content, and relevant quality control and assurance procedures. This study aims to help environmental geoscientists understand the technical process of 14C analysis of PAHs and inspire new scientific questions related to environmental science. To our knowledge, this is the first comprehensive review of the technical method of compound-specific 14C analysis for PAHs.


Carbon Radioisotopes , Environmental Monitoring , Polycyclic Aromatic Hydrocarbons , Polycyclic Aromatic Hydrocarbons/analysis , Environmental Monitoring/methods , Carbon Radioisotopes/analysis , Environmental Pollutants/analysis
2.
J Agric Food Chem ; 72(18): 10579-10583, 2024 May 08.
Article En | MEDLINE | ID: mdl-38683941

A 14C-based method was developed to study the rate and extent of covalent bond formation between ß-lactoglobulin and three model flavor compounds: a ketone (2-undecanone UDO), an aldehyde (decanal DAL), an isothiocyanate (2-phenylethyl isothiocyanate PEITC), and an unreactive "methods blank" (decane DEC). Aqueous protein solutions with one of the 14C-labeled model flavor compounds were placed in water baths at 25, 45, and 65 °C for 4 weeks measuring the amount of flavor: protein reaction at 1, 3, 7, 14, 21, and 28 days. UDO showed lowest reactivity (max of 0.9% of added compound reacted), DAL (max of 16.4% reacted), and PEITC (max of 71.8% reacted). All compounds showed a rapid initial reaction rate which slowed after ca. 7 days. It appears that only PEITC (at 65 °C) saturated all potential protein-reactive sites over the storage period.


Flavoring Agents , Isothiocyanates , Ketones , Lactoglobulins , Lactoglobulins/chemistry , Flavoring Agents/chemistry , Isothiocyanates/chemistry , Ketones/chemistry , Carbon Radioisotopes/analysis , Carbon Radioisotopes/chemistry , Aldehydes/chemistry , Kinetics
3.
Sci Rep ; 13(1): 22119, 2023 12 13.
Article En | MEDLINE | ID: mdl-38092830

Collagen glue has been used for nearly two centuries to consolidate bone material, although its prevalence in museum collections is only now becoming visible. Identifying and removing collagen glue is crucial before the execution of any geochemical or molecular analyses. Palaeolithic bone objects from old excavations intended for radiocarbon dating were first analysed using ZooMS (Zooarchaeology by Mass Spectrometry) to identify the animal species, however peaks characteristic of both cattle and whale were discovered. Two extraction methods for ZooMS were tested to identify the authentic animal species of these objects, which revealed that these were originally whale bone objects that had been consolidated with cattle collagen glue. This is the first time animal collagen glue has been identified in archaeological remains with ZooMS, illustrating again the incredible versatility of this technique. Another technique, Fourier Transform Infrared Spectroscopy in Attenuated Total Reflectance mode (FTIR-ATR), was also tested if it could rapidly identify the presence of collagen glue in archaeological bone material, which was not the case. Two other cleaning methods were tested to remove bone glue contamination prior to radiocarbon dating, along with two modified collagen extraction methods for ZooMS. These methods were applied to bone blank samples (FmC = 0.0031 ± 0.0002, (n = 219), 47 336 ± 277 yr BP) that were experimentally consolidated with collagen glue and to the Palaeolithic bone material (ca. 15 000 and 12 000 yr BP). The experimental bone blanks produced excellent 14C ages, suggesting the cleaning methods were successful, however the 14C ages for some of the Palaeolithic material remained too young considering their contextual age, suggesting that the collagen glue contamination had most likely cross-linked to the authentic collagen molecule. More research is needed in order to gain a deeper understanding of the occurrence and elimination of cross-linked collagen-based glues in material from museum collections.


Collagen , Radiometric Dating , Animals , Cattle , Radiometric Dating/methods , Carbon Radioisotopes/analysis , Collagen/chemistry , Bone and Bones/chemistry , Archaeology/methods , Whales
4.
Drug Metab Dispos ; 51(12): 1607-1614, 2023 Dec.
Article En | MEDLINE | ID: mdl-37684056

Pomotrelvir is an orally bioavailable, target antiviral inhibitor of the main protease (Mpro) of coronaviruses, including severe acute respiratory syndrome coronavirus 2, the etiological agent of Coronavirus Disease 2019. The pharmacokinetics, metabolism and elimination of two [14C]-labeled microtracers of 5 µCi/700 mg pomotrelvir with separate labeling positions (isotopomers), [lactam carbonyl-14C-pomotelvir] and [benzene ring-U-14C-pomotrelvir], following a single oral dose in healthy adult males was evaluated in two separate cohorts. Pomotrelvir was rapidly absorbed and eliminated primarily through metabolism and subsequently excreted via urine and feces. There were no differences in pomotrelvir pharmacokinetics between the two cohorts. The mean total radioactive dose recovered was 93.8% (n = 8) in the lactam cohort (58% in urine and 36% in feces) and 94.2% (n = 8) in the benzene cohort (75% in urine and 19% in feces), with ≥80% of [14C] recovered within 96 hours after dosing. About 5% and 3% of the intact pomotrelvir was recovered in feces and urine, respectively. Eleven major metabolites were detected and characterized using liquid chromatography-accelerator mass spectrometry and liquid chromatography tandem mass spectrometry methods, with three and six different metabolites elucidated in the samples collected from lactam and benzene cohorts, respectively, and two metabolites observed in both cohorts. The major metabolism pathway of pomotrelvir is through hydrolysis of its peptide bonds followed by phase II conjugations. These results support that the application of two radiolabeled isotopomers provided a comprehensive metabolite profiling analysis and was a successful approach in identifying the major disposition pathways of pomotrelvir that has complex routes of metabolism. SIGNIFICANCE STATEMENT: An unconventional approach using two differentially labeled [14C] microtracers, [lactam carbonyl-14C-pomotrelvir] and [benzene ring-U-14C-pomotrelvir] evaluated the mass balance of orally administered pomotrelvir in healthy adult males in two separate cohorts. The radioactive dose recovered in excreta was about 94% for both cohorts. While the two isotopomers of the radiolabeled-pomotrelvir showed no major differences in pharmacokinetics overall, they allowed for differential detection of their radiolabeled metabolites and appropriate characterization of their plasma exposure and excretion in urine and feces.


Benzene , Lactams , Adult , Humans , Male , Chromatography, High Pressure Liquid/methods , Benzene/analysis , Chromatography, Liquid , Biotransformation , Feces/chemistry , Lactams/analysis , Administration, Oral , Carbon Radioisotopes/analysis
5.
Drug Metab Dispos ; 51(10): 1419-1427, 2023 10.
Article En | MEDLINE | ID: mdl-37429728

The metabolism of lufotrelvir, a novel phosphate prodrug of PF-00835231 for the treatment of COVID-19, was evaluated in healthy human volunteers and clinical trial participants with COVID-19 following intravenous infusion. The prodrug was completely converted to PF-00835231 that was subsequently cleared by hydrolysis, hydroxylation, ketoreduction, epimerization, renal clearance, and secretion into the feces. The main circulating metabolite was a hydrolysis product (M7) that was present at concentrations greater than PF-00835231, and this was consistent between healthy volunteers and participants with COVID-19. On administration of [14C]lufotrelvir, only 63% of the dose was obtained in excreta over 10 days and total drug-related material demonstrated a prolonged terminal phase half-life in plasma. A considerable portion of the labeled material was unextractable from fecal homogenate and plasma. The position of the carbon-14 atom in the labeled material was at a leucine carbonyl, and pronase digestion of the pellet derived from extraction of the fecal homogenate showed that [14C]leucine was released. SIGNIFICANCE STATEMENT: Lufotrelvir is an experimental phosphate prodrug intravenous therapy investigated for the potential treatment of COVID-19 in a hospital setting. The overall metabolism of lufotrelvir was determined in human healthy volunteers and clinical trial participants with COVID-19. Conversion of the phosphate prodrug to the active drug PF-00835231 was complete and the subsequent metabolic clearance of the active drug was largely via amide bond hydrolysis. Substantial drug-related material was not recovered due to loss of the carbon-14 label to endogenous metabolism.


COVID-19 , Prodrugs , Humans , Carbon Radioisotopes/analysis , Infusions, Intravenous , RNA, Viral/analysis , Leucine , SARS-CoV-2 , Administration, Intravenous , Phosphates , Feces/chemistry
6.
J Forensic Sci ; 68(4): 1372-1378, 2023 Jul.
Article En | MEDLINE | ID: mdl-37288938

In cases where human remains are unidentified because there is no initial identification hypothesis, limited contextual information, and/or poor preservation, radiocarbon (14 C) dating may be a useful tool to further assist with identification. Through measuring the amount of 14 C remaining in organic material, such as bone, teeth, nail, or hair, radiocarbon dating may provide an estimated year of birth and year of death for a deceased person. This information, may assist in, establishing whether a case of unidentified human remains (UHR) is actually of medicolegal significance and therefore, requires forensic investigation and identification. This case series highlights the application of 14 C dating to seven of the 132 UHR cases in Victoria, Australia. Cortical bone was sampled from each case and the level of 14 C was measured to provide an estimated year of death. Four of the seven cases analyzed contained the levels of 14 C consistent with an archeological timeframe, one contained a level of 14 C consistent with a modern (i.e., of medicolegal significance) timeframe, and the results for the remaining two samples were inconclusive. Applying this technique not only reduced the number of UHR cases in Victoria but also has investigative, cultural, and practical implications for medicolegal casework in general.


Body Remains , Radiometric Dating , Humans , Victoria , Radiometric Dating/methods , Carbon Radioisotopes/analysis , Bone and Bones/chemistry
7.
PLoS One ; 18(3): e0274979, 2023.
Article En | MEDLINE | ID: mdl-36893143

The construction of the Iron Age Mediterranean chronology began in the Levant based on historical evidence and has been additionally supported in recent decades by means of radiocarbon analysis, although with variable precision and ratification. It is only in recent years that new evidence in the Aegean and the western Mediterranean has opened discussion towards its further acceptance as an authoritative i.e. highly reliable, and widely applicable historiographic network. Altogether, the Mediterranean Iron Age chronology has only undergone minor changes during the last hundred years. The Phoenician metropolis of Sidon in southern Lebanon now provides a new, large and robust dataset obtained through a combination of archaeological and 14C-radiometric analysis of materials from stratified contexts that allow their statistical assessment. The appearance of substantial amounts of pottery of Greek, Cypriot and Egyptian origin together with Phoenician local wares in a long stratigraphy is a benefit for the synchronisation of regional pottery styles and allows wider geographic correlation of relative chronological systems. The close association of the archaeological data with a long series of AMS-14C-dates on short-lived samples provides new evidence for the absolute dating of many of the regional pottery styles that are represented in the stratigraphy of Sidon, and contributes towards a considerable improvement of the Mediterranean chronology.


Radiometric Dating , Radiometry , Humans , Lebanon , Carbon Radioisotopes/analysis , Greece , Archaeology
8.
Drug Metab Dispos ; 51(4): 451-463, 2023 04.
Article En | MEDLINE | ID: mdl-36639243

This study evaluated the mass balance and disposition of AZD4831, a novel myeloperoxidase inhibitor, in six healthy participants using a 14C-labeled microtracer coupled with analysis by accelerator mass spectrometry (AMS). A single oral dose of 10 mg 14C-AZD4831 (14.8 kBq) was administered as a solution, and 14C levels were quantified by AMS in blood, urine, and feces over 336 hours postdose. AZD4831 was rapidly absorbed, and AZD4831 plasma concentrations declined in a biphasic manner, with a long half-life of 52 hours. AZD4831 was eliminated via metabolism and renal excretion. An N-carbamoyl glucuronide metabolite of AZD4831 (M7), formed primarily via UGT1A1, was the predominant circulating metabolite. Presumably, M7 contributed to the long half-life of AZD4831 via biliary elimination and hydrolysis/enterohepatic recirculation of AZD4831. On average, ∼84% of administered 14C-AZD4831 was recovered by 336 hours postdose (urine, 51.2%; feces, 32.4%). Between 32%-44% of the dose was excreted as unchanged AZD4831 in urine, indicating renal elimination as the major excretory route. Only 9.7% of overall fecal recovery was recorded in the first 48 hours, with the remainder excreted over 48%-336 hours, suggesting that most fecal recovery was due to biliary elimination. Furthermore, only 6% of unchanged AZD4831 was recovered in feces. Overall, the fraction of the administered AZD4831 dose absorbed was high. 14C-AZD4831 was well tolerated. These findings contribute to increasing evidence that human absorption, distribution, metabolism, and excretion studies can be performed with acceptable mass balance recovery at therapeutically relevant doses and low radiolabel-specific activity using an AMS-14C microtracer approach. SIGNIFICANCE STATEMENT: In this study, the human absorption, distribution, metabolism, and excretion (hADME) of the novel myeloperoxidase inhibitor AZD4831 was assessed following oral administration. This included investigation of the disposition of M7, the N-carbamoyl glucuronide metabolite. Resolution of challenges highlighted in this study contributes to increasing evidence that hADME objectives can be achieved in a single study for compounds with therapeutically relevant doses and low radiolabel-specific activity by using an AMS-14C microtracer approach, thus reducing the need for preclinical radiolabeled studies.


Glucuronides , Peroxidase , Humans , Glucuronides/analysis , Pyrimidines , Feces/chemistry , Mass Spectrometry , Administration, Oral , Carbon Radioisotopes/analysis
9.
Methods Mol Biol ; 2619: 91-98, 2023.
Article En | MEDLINE | ID: mdl-36662464

Bomb pulse refers to the sharp increase of the atmospheric levels of the carbon isotope 14C due to nuclear testing during the late 1950s and early 1960s. After the nuclear test ban, atmospheric 14C levels decreased exponentially because of the diffusion and equilibration with the ocean and biosphere, as well as the incorporation indirectly into all living cells. Thus, assessing the anthropogenic 14C serves as an isotopic chronometer providing the opportunity to estimate the age of a tissue and its components with a relatively high precision comparing it with the atmospheric levels at a certain time stamp.This protocol describes the use of the bomb pulse dating as a retrospective tracer of tissue components such as the glycosaminoglycans (GAGs) and subsequent proteoglycans turnover using accelerator mass spectrometry.


Glycosaminoglycans , Carbon Radioisotopes/analysis , Retrospective Studies , Carbon Isotopes
10.
Cancer Chemother Pharmacol ; 91(2): 143-156, 2023 02.
Article En | MEDLINE | ID: mdl-36572783

PURPOSE: SHC014748M is a potent, novel selective PI3Kδ isoform inhibitor and is proposed for the treatment of non-Hodgkin lymphoma and chronic lymphocytic leukemia/small lymphocytic lymphoma. This study investigated the pharmacokinetics, mass balance, metabolism and excretion of SHC014748M in Chinese male subjects following a single oral dose of 150 mg (100 µCi) [14C] SHC014748M. METHODS: Six healthy Chinese male subjects administrated an oral suspension of 150 mg (100 µCi) [14C] SHC014748M and the samples of blood, urine and feces were collected for measuring. Liquid chromatography-tandem mass spectrometry and liquid scintillation counter were utilized to obtain mass balance and the pharmacokinetic data. RESULTS: The median Tmax for [14C]-radioactivity was 1.6 ± 0.5 h after the oral administration of [14C] SHC014748M and the mean Cmax was 3863 ± 354 ng Eq./mL in plasma, while the mean Cmax, t1/2 values and AUC0-∞ values for total radioactivity in whole blood were 2466 ± 518 ng Eq./mL, 32.2 ± 30.5 h and 66,236 ± 44,232 h * ng Eq./mL, respectively. Fecal excretion was proposed as the predominant elimination route, accounting for a mean of 90.68 ± 11.38% of the administered dose, whereas the mean urine excretion was 6.00 ± 1.48% within 336 h post-dose. The proposed major metabolic pathway of [14C] SHC014748M in the human body were as follows: (I) monooxidation, (II) glucuronide acid conjugation, and (III) monoxide-hydrogenation. CONCLUSIONS: SHC014748M was absorbed, metabolized and excreted with unchanged SHC014748M as its main circulating component in plasma following oral administration. In addition, it was speculated that fecal excretion was the principal excretion pathway; meanwhile, monohydroxy, glucuronide conjugation, oxygen, and hydrogenation were the major clearance pathways of SHC014748M through urine and/or feces. TRIAL REGISTRATION: The trial registration number: CTR20202505.


Angiogenesis Inhibitors , Glucuronides , Protein Kinase Inhibitors , Humans , Male , Administration, Oral , Angiogenesis Inhibitors/pharmacokinetics , Carbon Radioisotopes/analysis , East Asian People , Feces/chemistry , Glucuronides/analysis , Protein Kinase Inhibitors/pharmacokinetics
11.
Forensic Sci Int ; 341: 111480, 2022 Dec.
Article En | MEDLINE | ID: mdl-36257096

The radiocarbon (14C) analysis of skeletonised human remains can provide vital information regarding the time since death. This study analysed the 14C content in both cortical and trabecular bone from the femur and rib of 18 human remains donated to the Australian Facility for Taphonomic Experimental Research. To determine the most appropriate bone to sample for 14C analysis when estimating the time since death, differences in turnover time between the bone types, and the difference between environmental 14C during the year of death (YOD) and the level of 14C found within the bone (i.e., the lag time) were examined. Overall, the average lag time for all donors was 25 years, with the cortical bone from femur samples providing the largest lag time (39 years) and the trabecular bone from rib samples containing the lowest level of 14C (most modern), with an average lag time of 13 years. The results of this study suggest that in cases of unidentified human remains, the analysis of trabecular bone from a rib may be preferred sample, as this bone contains the most recent 14C, and can provide an estimate of both the time since death, and a broad approximation of YOD.


Body Remains , Bone and Bones , Humans , Carbon Radioisotopes/analysis , Australia , Bone and Bones/chemistry , Femur/chemistry
12.
J Environ Radioact ; 255: 107006, 2022 Dec.
Article En | MEDLINE | ID: mdl-36162146

This is a detailed study on oxide (CO2) and reduced (hydrocarbons, CnHm) forms of 14C releases through gaseous effluents from the Kaiga nuclear power plant (NPP), on the West Coast of India, where 4 × 220 MW(e) pressurized heavy water reactors (PHWRs) are operating. The gaseous effluent from the common stack of reactor units 3 and 4 (each of 220 MW(e)) was sampled from 2017 to 2020 for 14C activity monitoring and analysed for 14C activity by liquid scintillation counting. The normalized release rate corresponding to the four-year monitoring period had a geometric mean value of 0.12 TBq GW(e)-1 a-1 (geometric standard deviation = 7.4), and the arithmetic mean with associated standard deviation was 0.75 ± 1.47 TBq GW(e)-1 a-1. The relative percentage contribution of reduced form (CH4) of 14C species was less than 1.27% of the total release. The normalized release rate from Kaiga NPP was similar to those reported for the other PHWR NPPs of the world. The 14C specific activity in the ambient air in the vicinity of the NPP was monitored at four locations. The maximum excess 14C activity values in the ambient air in the vicinity of the NPP, evaluated by comparing the specific activity recorded for the clean air region at ∼300 km from the NPP, were 65.1 Bq kg-1C (28.76 pMC) and 222.4 Bq kg-1C (98.23 pMC) for the years 2019 and 2020 respectively. In addition, the release rates were calculated from the Gaussian plume model using site-specific atmospheric dilution factors and the excess 14C specific activity measured at four off-site monitoring stations. The calculated values of release rates were in agreement (within a factor of ∼3) with the measured values.


Air Pollutants, Radioactive , Radiation Monitoring , Nuclear Power Plants , Carbon Radioisotopes/analysis , Deuterium Oxide , Air Pollutants, Radioactive/analysis , India , Gases
13.
Proc Natl Acad Sci U S A ; 119(28): e2122122119, 2022 07 12.
Article En | MEDLINE | ID: mdl-35867750

The precise and accurate determination of the radionuclide inventory in radioactive waste streams, including those generated during nuclear decommissioning, is a key aspect in establishing the best-suited nuclear waste management and disposal options. Radiocarbon ([Formula: see text]) is playing a crucial role in this scenario because it is one of the so-called difficult to measure isotopes; currently, [Formula: see text] analysis requires complex systems, such as accelerator mass spectrometry (AMS) or liquid scintillation counting (LSC). AMS has an outstanding limit of detection, but only a few facilities are available worldwide; LSC, which can have similar performance, is more widespread, but sample preparation can be nontrivial. In this paper, we demonstrate that the laser-based saturated-absorption cavity ring-down (SCAR) spectroscopic technique has several distinct advantages and represents a mature and accurate alternative for [Formula: see text] content determination in nuclear waste. As a proof-of-principle experiment, we show consistent results of AMS and SCAR for samples of concrete and graphite originating from nuclear installations. In particular, we determined mole fractions of 1.312(9) F[Formula: see text] and 30.951(7) F[Formula: see text] corresponding to ∼1.5 and 36.2 parts per trillion (ppt), respectively, for two different graphite samples originating from different regions of the Adiabatic Resonance Crossing activator prototype installed on one irradiation line of an MC40 Scanditronix cyclotron. Moreover, we measure a mole fraction of 0.593(8) F[Formula: see text] ([Formula: see text] ppt) from a concrete sample originating from an external wall of the Ispra-1 nuclear research reactor currently in the decommissioning phase.


Carbon Radioisotopes , Graphite , Radioactive Waste , Waste Management , Carbon Radioisotopes/analysis , Graphite/chemistry , Mass Spectrometry , Radioactive Waste/analysis , Radiometric Dating , Waste Management/methods
14.
Sci Total Environ ; 848: 157345, 2022 Nov 20.
Article En | MEDLINE | ID: mdl-35882321

Recently, the subsoils of ephemeral stream (arroyos) floodplains in the northern Chihuahuan Desert were discovered to contain large naturally occurring NO3- reservoirs (floodplain: ~38,000 kg NO3-N/ha; background: ~60 kg NO3-N/ha). These reservoirs may be mobilized through land use change or natural stream channel migration which makes differentiating between anthropogenic and natural groundwater NO3- sources challenging. In this study, the fate and sources of NO3- were investigated in an area with multiple NO3- sources such as accidental sewer line releases and sewage lagoons as well as natural reservoirs of subsoil NO3-. To differentiate sources, this study used a large suite of geochemical tools including δ15N[NO3], δ18O[NO3], δ15N[N2], δ13C[DIC], 14C, tritium (3H), dissolved gas concentrations, major ion chemistry, and contaminants of emerging concern (CEC) including artificial sweeteners. NO3- at sites with the highest concentrations (25 to 229 mg/L NO3-N) were determined to be largely sourced from naturally occurring subsoil NO3- based on δ15N[NO3] (<8 ‰) and mass ratios of Cl-/Br- (〈100) and NO3-/Cl- (>1.5). Anthropogenic NO3- was deciphered using mass ratios of Cl-/Br- (>120) and NO3-/Cl- (<1), δ15N[NO3] (>8 ‰), and CEC detections. Nitrogen isotope analyses indicated that denitrification is fairly limited in the field area. CEC were detected at 67 % of sites including 3H dead sites (<1 pCi/L) with low percent modern carbon-14 (PMC; <30 %). Local supply wells are 3H dead with low PMC; as 3H does not re-equilibrate and 14C is very slow to re-equilibrate during recirculation through infrastructure, sites with low PMC, 3H < 1 pCi/L, and CEC detections were interpreted as locations with substantial anthropogenic groundwater recharge. Neotame was used to identify locations of very recent (<15 years before present) or ongoing wastewater influxes to the aquifer. This work shows the important influence of naturally occurring subsoil NO3- reservoirs on groundwater in arid regions and the major contribution of artificial recharge.


Groundwater , Water Pollutants, Chemical , Carbon Radioisotopes/analysis , Environmental Monitoring , Groundwater/analysis , Nitrates/analysis , Nitrogen Isotopes/analysis , Nitrogen Oxides/analysis , Sewage/analysis , Sweetening Agents/analysis , Tritium , Wastewater/analysis , Water Pollutants, Chemical/analysis
17.
Forensic Sci Int ; 335: 111292, 2022 Jun.
Article En | MEDLINE | ID: mdl-35429776

Art objects form an essential part of cultural heritage and are appreciated for their artistic values. However, the observed investment in art and capacity for high monetary returns encourages counterfeiting of art objects. The art market's lack of transparency and traditional confidential protocols amplifies the problem. Radiocarbon analysis provides a tool to detect anachronistic materials. Measurement of bomb peak radiocarbon, which was observed in the atmosphere during the last 70 years, can provide clear evidence of post-1950 material. Here we briefly introduce the method and discuss its application in detecting forgeries. Three accelerator mass spectrometry AMS laboratories performed a 14C dating inter-comparison study on the material used in art. Results obtained on modern cotton paper, two antique sheets of paper, one parchment, and one textile demonstrate the radiocarbon dating capacity to date the material accurately. The excellent agreement between laboratories is crucial for the broader application of this scientific tool in forensic studies and court cases.


Art , Radiometric Dating , Carbon Radioisotopes/analysis , Mass Spectrometry , Radiometric Dating/methods
18.
Xenobiotica ; 52(3): 254-264, 2022 Mar.
Article En | MEDLINE | ID: mdl-35373704

YY-20394, a highly selective PI3Kδ inhibitor, is under NDA submission for treating follicular lymphoma in China. The absorption, metabolism, and excretion of YY-20394 were evaluated in healthy Chinese male subjects following a single oral dose of 80 mg [14C]YY-20394 (100 µCi).Within 264 h post-dose, 92.1% of the administered dose was recovered, with 58.1% from urine and 34.0% from faeces. YY-20394 was rapidly absorbed in humans, and the peak plasma concentrations occurred at 1.0 h. The absorbed drug fraction was at least 58.1% according to urine recovery.In addition to the parent drug, nine metabolites were identified in plasma, urine, and faeces. Unchanged YY-20394 was the predominant drug-related component in plasma (accounting for 68.4% of the total radioactivity), urine (accounting for 90.0% of the urinary radioactivity) and faeces (accounting for 41.7% of the faecal radioactivity). In humans, the major metabolic sites were the morphine ring and side chains of piperidine rings. The major metabolic pathways involved N-dealkylation, O-dealkylation, glucuronidation and acetylation.Overall, renal elimination played a significant role in the disposition of YY-20394, and the morphine ring and the side chain of the piperidine ring was the predominant metabolic sites.


Phosphatidylinositol 3-Kinases , Protein Kinase Inhibitors , Administration, Oral , Angiogenesis Inhibitors , Carbon Radioisotopes/analysis , Feces/chemistry , Humans , Male , Morphine Derivatives/analysis , Phosphoinositide-3 Kinase Inhibitors , Piperidines
19.
J Environ Radioact ; 248: 106886, 2022 Jul.
Article En | MEDLINE | ID: mdl-35472689

Carbon-14 (14C) is one of the main radionuclides released during normal operation by nuclear power plants, nuclear defense facilities and nuclear fuel reprocessing plants. It is mainly released in the form of carbon dioxide gas denoted 14CO2, which has the specificity of being incorporated into food webs via photosynthesis by primary producing organisms. In order to better assess the environmental and human impacts of 14CO2 under normal operating conditions - or after potential accidental releases - from nuclear facilities, it is necessary to improve our understanding and our predictions of the behaviour of this radionuclide along the human food chain. To achieve this goal, the International Atomic Energy Agency (IAEA) Environmental Modelling for Radiation Safety (EMRAS) model evaluation programme included the Tritium and 14C Working Group (TCWG) which dealt with the intercomparison exercises between several models of environmental transfer in the case of routine and accidental releases of these radionuclides into the environment, and their performance testing. The TOCATTA-χ model developed at IRSN is a dynamic compartment model with high temporal resolution, which simulates the transfer of 14C (and tritium) in grassland ecosystems exposed to gaseous 14CO2 (and HTO) from nuclear facilities under normal or accidental operating conditions. Following this work, IRSN proposed a related project to extend the application of the TOCATTA-χ model to 14C estimates in leafy vegetables, fruits and roots. This article deals with the application of the TOCATTA-χ model to a specific real-case scenario identified within the framework of the TCWG. The scenario provides experimental data and predicted results from models developed at the international level. Model-model and model-data intercomparison exercises were thus carried out to validate the evaluations of the TOCATTA-χ model. In addition, this paper discusses the parameterization of the TOCATTA-χ model for this scenario and the development of modules for 14C concentrations in potato tubers, based on the assumption that photosynthetic transfer occurs directly from leaves to tubers and depends mainly on the growth stage of the tubers. It is observed that the predictions of the TOCATTA-χ model for the concentrations of 14C in leaves and tubers are slightly better than the other models due to the modelling approaches adopted by TOCATTA-χ for the calculation of key ecophysiological processes that govern plant functioning. Overall, the TOCATTA-χ model reduces the Root Mean Square Error (RMSE) by a factor of less than 8 compared to other models. In addition, most of the predicted results of the TOCATTA-χ model better match the measurements and are within the measurement uncertainty limit, while a few are overestimated. This could be due to the high uncertainty associated with the experimentally measured 14C activities, which reflects the field variability in plant growth rate.


Air Pollutants, Radioactive , Radiation Monitoring , Air Pollutants, Radioactive/analysis , Carbon Dioxide , Carbon Radioisotopes/analysis , Ecosystem , Humans , Radiation Monitoring/methods , Tritium/analysis
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