Typical Tire Additives in River Water: Leaching, Transformation, and Environmental Risk Assessment.

Tire wear particles (TWPs) released during vehicle driving can enter water bodies, leading to leaching of tire additives (TAs) in aquatic environments. However, the transformation behavior and related ecological impacts of TAs and their transformation products (TPs) remain unclear. In this study, laboratory-based simulation experiments and field investigations were conducted to explore the transformation mechanisms and ecological risks of TAs. After being placed in river water for 24 h, about 7-95% of 12 investigated TAs in TWPs were leached. Forty-eight TPs from eight TAs were tentatively identified along with different transformation pathways via suspect screening by high-resolution mass spectrometry. Semiquantitative results indicated that TPs derived from N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylene-diamine (6PPD) were predominant in leachates, while aryl hydrolysis and quinone pathways were the main transformation pathways. Field investigations on urban surface water samples from 16 sites in Hong Kong revealed the occurrence of 17 TAs and 1 TP, with concentrations ranging from 13.9 to 2230 ng/L (median ± standard deviation: 226 ± 534 ng/L). Sixteen TPs from six TAs were additionally identified via suspect screening. It is estimated that 6PPD-quinone and seven TAs could pose medium to high ecological risk, while N-(1,3-dimethylbutyl)-N'-phenyl-p-quinonediimine, a frequently detected TP, was identified as a persistent-bioaccumulative-toxic substance.

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) and nutrients from two constructed wetlands in a city of southeastern China.

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are a large class of toxic contaminants. Nutrients are closely related to the ecological health of aquatic systems. Both have received widespread global attention. This study investigated the concentrations, compositions, and spatial distributions of PFAS and nutrients in surface water from two constructed wetlands and the nearby drinking water treatment plants (DWTPs). We explored the natural environmental factors and human activities that affect the composition and distribution of pollutants in wetlands and assessed the ability of the DWTPs to remove contaminants. Concentrations of ∑32PFAS varied from 153 to 405 ng/L. Hexafluoropropylene oxide trimer acid (HFPO-TA) was the predominant substance accounting for 45 % of ∑32PFAS concentrations. It might originate from the emissions of indirect sources of PFAS related manufacturers. The detection rate of 6:2 fluorotelomer carboxylic acid (6:2 FTCA) was 100 % with concentrations ranging from 0.915 to 19.7 ng/L 6:2 FTCA might come from the biotransformation of indirect sources in the air. Concentrations of total nitrogen (TN) and total phosphorus (TP) were from 1.47 to 3.54 mg/L, and non-detect (ND) to 0.323 mg/L, respectively. Constructed wetlands could effectively remove PFAS under nutrient stress, however, the removal of PFAS depends on the characteristics of specific compounds and their sources. The removal rates for PFAS and nutrients could be promoted through artificial dredging. But wetland bioremediation could have two opposing effects. On the one hand, plants can take up pollutants from water via roots, leading to pollutant removal and purification. On the other hand, plants may also absorb precursor intermediates from the air through leaves and release them into the water, leading to increased pollutant concentrations. Thirty-two emerging PFAS were identified by high resolution mass spectrum. The drinking water treatment process removed PFAS and nutrients below the drinking water quality standards of China, however, 9 non-target PFAS compounds were still found in tap water. These results provide case support and a theoretical basis for the pollution control and sustainable development of typical ecological wetlands used as drinking water sources.

Home practices can mitigate furan and derivatives in vegetable-based infant meals.

This study assessed the impact of current home practices including reheating, standing, and stirring on mitigation of furan and its derivatives in vegetable-based infant meals. Three vegetable-based infant meals (vegetables alone, with fish, with meat) underwent different home practices including reheating, post-reheating standing (60, 120 and 240 s) and post-reheating stirring (30, 60, 120 and 240 s). Targeted quantification of furan, 2-methylfuran (2-MF) and 3-methylfuran (3-MF) and exploration of additional furan derivatives were undertaken in treated and untreated vegetable-based infant meals using SHS-GC-Q Exactive-Orbitrap-MS. For the three compounds, the quality of the measurements was first validated with suitable linearity, limits of quantification, precision and recoveries. A second step highlighted high concentrations of furan (78.5-103.9 µg/kg), 2-MF (4.8-10.1 µg/kg) and 3-MF (3.4-5.8 µg/kg) in the three vegetable-based infant meals before preparation and the assessment of the cumulative risk related to these three furan compounds confirmed the relevance of studying home mitigation strategies. The third step showed that post-reheating stirring was the most effective home practice for mitigation, with maximum observed reductions of 66.3, 59.9 and 57.7 % for furan, 2-MF and 3-MF, respectively. In a fourth step, a suspect screening approach carried out on SHS-GC-Q Exactive-Orbitrap MS data revealed the presence of 2-ethyl-, 2-ethyl-5-methyl-, 2-butyl- and 2-vinyl-furan in vegetable-based meals and showed a similar mitigation trend of home practices on the relative concentrations of these four additional furan derivatives. Finally, despite a significant mitigation reaching 69 % of the furan concentration, the combined effect of home practices on furan compounds was not sufficient to rule out the risk associated with the consumption of vegetable-based infant foods and additional options are discussed.

Pesticides and transformation products footprint in Greek market basket vegetables: Comprehensive screening by HRMS and health risk assessment.

Healthy dietary habits encourage vegetable consumption. Although pesticide use in crops may negatively affect human health through food intake, it can also contaminate aquatic and terrestrial environments. Thus, monitoring pesticides in high-consumption matrices is crucial. This study conducted a complete workflow of analysis, including a step of target analysis of 30 widely used pesticides and a subsequent step of suspect screening. A validated QuEChERS method was employed to analyze 61 samples of fruiting vegetables and cucurbits, packaged leafy greens, and root and tuber vegetables, commercially distributed across Greece. The method proved to be highly efficient for all validation characteristics. After target analysis, the change in the residue levels detected during sample processing was evaluated as a case study using available literature data. A health risk assessment based on diet indicated acute and chronic hazard quotients (aHQ and cHQ) and chronic hazard index (cHI) values below 1. Concerning suspect screening, 53 additional identifications of pesticides and transformation products (TPs) were revealed, totaling 86 detections. Overall, 18 parent pesticide compounds and 5 TPs were identified. Ultimately, this approach is expected to provide added value in pesticide and TPs analysis of food matrices without prior data, minimizing experimental time and costs.

Identification of candidate exposure biomarkers for acetyl tributyl citrate and acetyl triethyl citrate using suspect screening in human liver microsomes.

Acetyl tributyl citrate (ATBC) and acetyl triethyl citrate (ATEC) are increasingly used as alternatives to phthalates in various products, including food packaging, medical devices, and personal care items, raising concerns about their potential health impacts. This study aimed to investigate the in vitro human metabolism of ATBC and ATEC and identify potential exposure biomarkers applicable in human biomonitoring. Pooled human liver microsomes were utilized to conduct in vitro metabolism assays of deuterium labeled ATBC (ATBC-d3) and ATEC, and ultra performance liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (UPLC-qToF/MS) was employed for analysis. Suspect screening workflow and confidence level assignment were applied for metabolite identification. Time-course analysis revealed rapid metabolism of both compounds, with estimated apparent half-lives of approximately 5 min for ATBC-d3 and less than 15 min for ATEC. Eleven metabolites were identified for ATBC-d3 and six for ATEC. The predominant chemical reactions observed were carboxylic ester hydrolysis, deacetylation, and hydroxylation. Based on their abundance and specificity, MB1 (hydroxylated) and MB11 (hydrolyzed and hydroxylated) were proposed as candidate exposure biomarkers for ATBC, and ME1 (hydrolyzed and deacetylated) for ATEC. The identified metabolites and proposed sequences of kinetic process enhance our understanding of the fate of these compounds in the human body, potentially informing future toxicological assessments and guiding the development of more comprehensive human biomonitoring strategies.

Comprehensive monitoring and prioritizing for contaminants of emerging concern in the Upper Yangtze River, China: An integrated approach.

Contaminants of emerging concern (CECs) in aquatic environments can adversely impact ecosystems and human health even at low concentrations. This study assessed the risk of 162 CECs, including neonicotinoid pesticides, triazine pesticides, carbamate pesticides, psychoactive substances, organophosphate esters, antidepressants, per- and polyfluoroalkyl substances, and antibiotics in 10 drinking water sources and two tributaries (Jialing and Wujiang Rivers) of the Upper Yangtze River in Chongqing, China. Target screening detected 156 CECs at 0.01-2218.2 ng/L, while suspect screening via LC-QTOF-MS identified 64 CECs, with 13 pesticides, 29 pharmaceuticals and personal care products, and 2 industrial chemicals reported for the first time in the Yangtze River Basin. Risk quotient-based ecological risk assessment revealed that 48 CECs posed medium to high risks (RQ > 0.1) to aquatic life, with antibiotics (n = 20) as the main contributors. Non-carcinogenic risks were below negligible levels, but carcinogenic risks from neonicotinoids, triazines, antidepressants, and antibiotics were concerning. A multi-criteria prioritization approach integrating occurrence, physico-chemical properties, and toxicological data ranked 26 CECs as high priority. This study underscores the importance of comprehensive CEC screening in rivers and provides insights for future monitoring and management strategies.

Tracking Extensive Portfolio of Cyanotoxins in Five-Year Lake Survey and Identifying Indicator Metabolites of Cyanobacterial Taxa.

Cyanobacterial blooms require monitoring, as they pose a threat to ecosystems and human health, especially by the release of toxins. Along with widely reported microcystins, cyanobacteria coproduce other bioactive metabolites; however, information about their dynamics in surface waters is sparse. We investigated dynamics across full bloom successions throughout a five-year lake monitoring campaign (Greifensee, Switzerland) spanning 150 sampling dates. We conducted extensive suspect screening of cyanobacterial metabolites using the database CyanoMetDB. Across all 850 samples, 35 metabolites regularly co-occurred. Microcystins were present in 70% of samples, with [d-Asp3,(E)-Dhb7]MC-RR reaching concentrations of 70 ng/L. Anabaenopeptins, meanwhile, were detected in 95% of all samples with concentrations of Oscillamide Y up to 100-fold higher than microcystins. Based on LC-MS response and frequency, we identified indicator metabolites exclusively produced by one of three cyanobacteria isolated from the lake, these being [d-Asp3,(E)-Dhb7]MC-RR from Planktothrix sp. G2020, Microginin 761B from Microcystis sp. G2011, and Ferintoic acid B from Microcystis sp. G2020. These indicators showed distinct temporal trends and peaking seasons that reflect the variance in either the abundance of the producing cyanobacteria or their toxin production dynamics. Our approach demonstrates that selecting high LC-MS response and frequent and species-specific indicator metabolites can be advantageous for cyanobacterial monitoring.

Optimized analytical strategy based on high-resolution mass spectrometry for unveiling associations between long-term chemical exposome in hair and Alzheimer's disease.

Exposure to environmental pollutants or contaminants is correlated with detrimental effects on human health, such as neurodegenerative diseases. Adopting hair as a biological matrix for biomonitoring is a significant innovation, since it can reflect the long-term chemical exposome, spanning months to years. However, only a limited number of studies have developed analytical strategies for profiling the chemical exposome in this heterogeneous biological matrix. In this study, a systematic investigation of the chemical extraction procedure from human hair was conducted, using a design of experiments and a high-resolution mass spectrometry (HRMS)-based suspect screening approach. The PlackettBurman (PB) design was applied to identify the significant variables influencing the number of detected features. Then, a central composite design was implemented to optimize the levels of each identified significant variable. Under the optimal conditions-15-minute pulverization, 25 mg of hair weight, 40 min of sonication, and a sonication temperature of 35 °C-approximately 32,000 and 15,000 aligned features were detected in positive and negative ion modes, respectively. This optimized analytical procedure was applied to hair samples from patients with Alzheimer's disease (AD) and individuals with normal cognitive function. Overall, 307 chemicals were identified using the suspect screening approach, with 37 chemicals differentiating patients with AD from controls. This study not only optimized an analytical procedure for characterizing the long-term chemical exposome in human hair but also explored the associations between AD and environmental factors.

Fungicide Metabolite MS2 Spectral Libraries for Comprehensive Human Biomonitoring.

Fungicides undergo rapid metabolism and are excreted in the urine. There are few methods for screening these ubiquitous compounds, which have a high potential for human exposure. High-resolution mass spectrometry (HRMS) is a suitable technique to assess fungicide exposures; however, there is a lack of spectral libraries for fungicide annotation and in particular for downstream metabolites. We created spectral libraries for 32 fungicides for suspect screening. Fungicide standards were administered to mice, and 24-h urine was analyzed using hydrophilic interaction and reversed-phase chromatography coupled to hybrid quadrupole-orbitrap mass spectrometry. Suspect metabolite MS2 spectra for library creation were selected based on the ratio of exposed-to-control mouse urine. MS2 libraries were applied to urine collected from female university students (n = 73). Several tetraconazole and tebuconazole metabolites were detected in 3% (2/73) of the samples. The creation of comprehensive suspect screening MS2 libraries is a useful tool to detect fungicide exposure for human biomonitoring.

Critical review on in silico methods for structural annotation of chemicals detected with LC/HRMS non-targeted screening.

Non-targeted screening with liquid chromatography coupled to high-resolution mass spectrometry (LC/HRMS) is increasingly leveraging in silico methods, including machine learning, to obtain candidate structures for structural annotation of LC/HRMS features and their further prioritization. Candidate structures are commonly retrieved based on the tandem mass spectral information either from spectral or structural databases; however, the vast majority of the detected LC/HRMS features remain unannotated, constituting what we refer to as a part of the unknown chemical space. Recently, the exploration of this chemical space has become accessible through generative models. Furthermore, the evaluation of the candidate structures benefits from the complementary empirical analytical information such as retention time, collision cross section values, and ionization type. In this critical review, we provide an overview of the current approaches for retrieving and prioritizing candidate structures. These approaches come with their own set of advantages and limitations, as we showcase in the example of structural annotation of ten known and ten unknown LC/HRMS features. We emphasize that these limitations stem from both experimental and computational considerations. Finally, we highlight three key considerations for the future development of in silico methods.

Degradation pathways of sulfamethoxazole under phototransformation processes: A data base of the major transformation products for their environmental monitoring.

Sulfamethoxazole (SMX) is frequently detected in wastewater and aquatic environments worldwide at concentrations from ng L-1 to µg L-1. Unfortunately, SMX is not completely removed in municipal wastewater treatment plants (WWTPs), thus, SMX and their transformation products (TPs) are discharged into aquatic environments, where can be transformed by phototransformation reactions. In this study, the phototransformation of SMX as well as generation of their major TPs under photolysis and photocatalysis processes was reviewed. SMX can be totally removed under photolysis and photocatalysis processes in aqueous solutions using simulated or natural radiation. Degradation pathways such as isomerization, hydroxylation, fragmentation, nitration, and substitution reactions were identified during the generation of the major TPs of SMX. Particularly, 26 TPs were considered for the creation of a data base of the major TPs of SMX generated under phototransformation processes. These 26 compounds could be used as reference during the SMX monitoring both wastewater and water bodies, using analytic methodologies such as target analysis and suspect screening. A data base of the major TPs of pharmaceuticals active compounds (PhACs) as SMX could help to implementation of best environmental monitoring programs for the study of the environmental risks both PhACs and their TPs with highest occurrence in aquatic environments.

An automated and high-throughput data processing workflow for PFAS identification in biota by direct infusion ultra-high resolution mass spectrometry.

The increasing recognition of the health impacts from human exposure to per- and polyfluorinated alkyl substances (PFAS) has surged the need for sophisticated analytical techniques and advanced data analyses, especially for assessing exposure by food of animal origin. Despite the existence of nearly 15,000 PFAS listed in the CompTox chemicals dashboard by the US Environmental Protection Agency, conventional monitoring and suspect screening methods often fall short, covering only a fraction of these substances. This study introduces an innovative automated data processing workflow, named PFlow, for identifying PFAS in environmental samples using direct infusion Fourier transform ion cyclotron resonance mass spectrometry (DI-FT-ICR MS). PFlow's validation on a bream liver sample, representative of low-concentration biota, involves data pre-processing, annotation of PFAS based on their precursor masses, and verification through isotopologues. Notably, PFlow annotated 17 PFAS absent in the comprehensive targeted approach and tentatively identified an additional 53 compounds, thereby demonstrating its efficiency in enhancing PFAS detection coverage. From an initial dataset of 30,332 distinct m/z values, PFlow thoroughly narrowed down the candidates to 84 potential PFAS compounds, utilizing precise mass measurements and chemical logic criteria, underscoring its potential in advancing our understanding of PFAS prevalence and of human exposure.

Wristband Personal Passive Samplers and Suspect Screening Methods Highlight Gender Disparities in Chemical Exposures.

Wristband personal samplers enable human exposure assessments for a diverse range of chemical contaminants and exposure settings with a previously unattainable scale and cost-effectiveness. Paired with nontargeted analyses, wristbands can provide important exposure monitoring data to expand our understanding of the environmental exposome. Here, a custom scripted suspect screening workflow was developed in the R programming language for feature selection and chemical annotations using gas chromatography-high-resolution mass spectrometry data acquired from the analysis of wristband samples collected from five different cohorts. The workflow includes blank subtraction, internal standard normalization, prediction of chemical uses in products, and feature annotation using multiple library search metrics and metadata from PubChem, among other functionalities. The workflow was developed and validated against 104 analytes identified by targeted analytical results in previously published reports of wristbands. A true positive rate of 62 and 48% in a quality control matrix and wristband samples, respectively, was observed for our optimum set of parameters. Feature analysis identified 458 features that were significantly higher on female-worn wristbands and only 21 features that were significantly higher on male-worn wristbands across all cohorts. Tentative identifications suggest that personal care products are a primary driver of the differences observed.

Combining Advanced Analytical Methodologies to Uncover Suspect PFAS and Fluorinated Pharmaceutical Contributions to Extractable Organic Fluorine in Human Serum (Tromsø Study).

A growing number of studies have reported that routinely monitored per- and polyfluoroalkyl substances (PFAS) are not sufficient to explain the extractable organic fluorine (EOF) measured in human blood. In this study, we address this gap by screening pooled human serum collected over 3 decades (1986-2015) in Tromsø (Norway) for >5000 PFAS and >300 fluorinated pharmaceuticals. We combined multiple analytical techniques (direct infusion Fourier transform ion cyclotron resonance mass spectrometry, liquid chromatography-Orbitrap-high-resolution mass spectrometry, and total oxidizable precursors assay) in a three-step suspect screening process which aimed at unequivocal suspect identification. This approach uncovered the presence of one PFAS and eight fluorinated pharmaceuticals (including some metabolites) in human serum. While the PFAS suspect only accounted for 2-4% of the EOF, fluorinated pharmaceuticals accounted for 0-63% of the EOF, and their contribution increased in recent years. Although fluorinated pharmaceuticals often contain only 1-3 fluorine atoms, our results indicate that they can contribute significantly to the EOF. Indeed, the contribution from fluorinated pharmaceuticals allowed us to close the organofluorine mass balance in pooled serum from 2015, indicating a good understanding of organofluorine compounds in humans. However, a portion of the EOF in human serum from 1986 and 2007 still remained unexplained.

Identification and quantification of acetyl tributyl citrate (ATBC) metabolites using human liver microsomes and human urine.

Plasticizers are chemicals that make plastics flexible, and phthalates are commonly used. Due to the toxic effects of phthalates, there is increasing use of non-phthalate plasticizers like acetyl tributyl citrate (ATBC). ATBC has emerged as a safer alternative, yet concerns about its long-term safety persist due to its high leachability and potential endocrine-disrupting effects. This study aims to identify ATBC metabolites using human liver microsomes and suspect screening methods, and to explore potential urinary biomarkers for ATBC exposure. Using ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry, we identified ATBC metabolites, including acetyl dibutyl citrate (ADBC), tributyl citrate (TBC), and dibutyl citrate (DBC). Urine samples from 15 participants revealed the presence of ADBC in 5, TBC in 11, and DBC in all samples, with DBC concentrations pointedly higher than the other metabolites. These metabolites show promise as biomarkers for ATBC exposure, though further validation with human data is required. Our results underscore the need for comprehensive studies on ATBC metabolism, exposure pathways, and urinary excretion to accurately assess human exposure levels.

Targeted quantification and untargeted exploration of furan and derivatives in infant food by headspace extraction-gas chromatography-Q Exactive Orbitrap mass spectrometry.

The aim of the present study was to assess the performance and complementarity of methods capable of both quantifying furan, 2-Methylfuran (2-MF) and 3-Methylfuran (3-MF) in infant foods, but also to comprehensively explore other furan derivatives. It is more particularly a question of validating and comparing the couplings of the two headspace extraction methods most used for the analysis of furan compounds - Headspace Solid Phase Microextraction (HS-SPME) and Static HeadSpace (SHS) - with gas chromatography hyphenated to a high-resolution mass detector (Q Exactive-Orbitrap MS) which allows both targeted quantification and suspect screening. Firstly, the accuracy profile approach was implemented to assess, validate and compare HS-SPME- and SHS-GC-Q Exactive-Orbitrap MS for the quantification of furan in two model infant foods, apple puree and first infant formula. SHS-GC-Q Exactive-Orbitrap MS, showed better accuracy (uncertainty < 17.2 % vs 22.5 % for HS-SPME GC-Q Exactive-Orbitrap MS) and better sensitivity (LOQ < 2.8 vs LOQ < 4.0 µg/kg) over a broader validation range (2-100 µg/kg vs 5-100 µg/kg in apple puree). Secondly, SHS-GC-Q Exactive-Orbitrap MS was assessed and validated by accuracy profile for the quantification of 2-MF and 3-MF, with performance close to those for furan except for 3-MF in apple puree. Thirdly, SHS-GC-Q Exactive-Orbitrap MS was used to quantify the levels of these compounds in 20 commercial samples (n = 3) belonging to the four main categories of infant food (infant formulae, fruit purees, infant cereals, vegetable/fish baby meals). Furan was quantified in 75 % of the samples, with maximum levels in the vegetable/fish-based infant foods (up to 127 µg/kg) while 2-MF and 3-MF were quantified in 45 % and 15 % of products respectively, with maximum levels of 14.1 µg/kg in follow-on formula 3rd age and 9.2 µg/kg in apple puree. Finally, SHS- and HS-SPME-GC-Q Exactive-Orbitrap MS data of the 20 infant products were processed in suspect screening mode using Compound DiscovererTM software. Coupling with HS-SPME, it made it possible to identify 13 additional furan derivatives, i.e. 5 more than with SHS. The relevance and safety status of the compounds identified are discussed.

GC × GC-HRMS with complementary ionization methods in the suspect screening analysis of fragrance allergens: overwhelming or justified?

Modern gas chromatography-mass spectrometry (GC-MS) allows for the analysis of complex samples, such as fragrances. However, identifying all the constituents in natural fragrance mixtures, especially allergens that need to be listed on product labels, is a significant challenge. This is primarily due to the high complexity of the sample and the fact that electron ionization, the most commonly used ionization method in GC-MS, produces numerous nonspecific fragment ions, often resulting in the absence or very low abundance of the molecular ion. These factors affect confidence in assigning the analyte. In this study, we demonstrate that the combination of GC × GC separation, with high mass resolution and accurate mass measurements, as well as chemical ionization in addition to traditional electron ionization, becomes an efficient tool for reliable qualitative analysis of a mixture containing 100 fragrance allergens, even when many of them are closely related species or isomers. The proposed approach expands the applicability of the comprehensive GC × GC-HRMS method, which includes complementary ionization techniques, from studies on anthropogenic priority pollutants and emerging contaminants to the analysis of natural products. Although targeted qualitative and quantitative analysis of allergens in the modern laboratories is well organized, GC × GC-HRMS, being a useful complement to routine quality control of volatile allergens in fragrances, definitely gives an additional contribution to the analytical cases when conventional 1D-GC-MS faces some problems or uncertainties.

Thermally induced changes in the profiles of phytocannabinoids and other bioactive compounds in Cannabis sativa L. inflorescences.

Phytocannabinoids occurring in Cannabis Sativa L. are unique secondary metabolites possessing interesting pharmacological activities. In this study, the dynamics of thermally induced (60 and 120 °C) phytocannabinoid reactions in four cannabis varieties were investigated. Using UHPLC-HRMS/MS, 40 phytocannabinoids were involved in target analysis, and an additional 281 compounds with cannabinoid-like structures and 258 non-cannabinoid bioactive compounds were subjected to suspect screening. As expected, the key reaction was the decarboxylation of acidic phytocannabinoids. Nevertheless, the rate constants differed among cannabis varieties, documenting the matrix-dependence of this process. Besides neutral counterparts of acidic species, ́new bioactive compounds such as hydroxyquinones were found in heated samples. In addition, changes in other bioactive compounds with both cannabinoid-like and non-cannabinoid structures were documented during cannabis heating at 120 °C. The data document the complexity of heat-induced processes and provide a further understanding of changes in bioactivities occurring under such conditions.

Unraveling the Pollution and Discharge of Aminophenyl Sulfone Compounds, Sulfonamide Antibiotics, and Their Acetylation Products in Municipal Wastewater Treatment Plants.

Aminophenyl sulfone compounds (ASCs) are widely used in various fields, such as the pharmaceutical and textile industries. ASCs and their primary acetylation products are inevitably discharged into the environment. However, the high toxicity of ASCs could be released from the deacetylation of acetylation products. Still, the occurrence and ecological risks of ASCs and their acetylation products remain largely unknown. Here, we integrated all of the existing ASCs based on the core structure, together with their potential acetylation products, to establish a database covering 1105 compounds. By combining the database with R programming, 45 ASCs, sulfonamides, and their acetylation products were identified in the influent and effluent of 19 municipal wastewater treatment plants in 4 cities of China. 13 of them were detected for the first time in the aquatic environment, and 12 acetylation products were newly identified. The cumulative concentrations of 45 compounds in the influent and effluent were in the range of 231-9.96 × 103 and 26-2.70 × 103 ng/L, respectively. The proportion of the unrecognized compounds accounted for 60.6% of the influent and 62.8% of the effluent. Furthermore, nearly half of the ASCs (46.7%), other sulfonamides (49.9%), and their acetylation products (46.2%) were discharged from the effluent, posing a low-to-medium risk to aquatic organisms. The results provide a guideline for future monitoring programs, particularly for sulfadiazine and dronedarone, and emphasize that the ecological risk of ASCs, sulfonamides, and their acetylation products needs to be considered in the aquatic environment.

Nontarget and suspect screening reveals the presence of multiple plastic-related compounds in polar bear, killer whale, narwhal and long-finned pilot whale blubber from East Greenland.

The monitoring of legacy contaminants in sentinel northern marine mammals has revealed some of the highest concentrations globally. However, investigations into the presence of chemicals of emerging Arctic concern (CEACs) and other lesser-known chemicals are rarely conducted, if at all. Here, we used a nontarget/suspect approach to screen for thousands of different chemicals, including many CEACs and plastic-related compounds (PRCs) in blubber/adipose from killer whales (Orcinus orca), narwhals (Monodon monoceros), long-finned pilot whales (Globicephala melas), and polar bears (Ursus maritimus) in East Greenland. 138 compounds were tentatively identified mostly as PRCs, and four were confirmed using authentic standards: di(2-ethylhexyl) phthalate (DEHP), diethyl phthalate (DEP), di(2-propylheptyl) phthalate (DPHP), and one antioxidant (Irganox 1010). Three other PRCs, a nonylphenol isomer, 2,6-di-tert-butylphenol, and dioctyl sebacate, exhibited fragmentation patterns matching those in library databases. While phthalates were only above detection limits in some polar bear and narwhal, Irganox 1010, nonylphenol, and 2,6-di-tert-butylphenol were detected in >50% of all samples. This study represents the first application of a nontarget/suspect screening approach in Arctic cetaceans, leading to the identification of multiple PRCs in their blubber. Further nontarget analyses are warranted to comprehensively characterize the extent of CEAC and PRC contamination within Arctic marine food webs.