Occurrence of benzothiazole, benzotriazole and benzenesulfonamide derivates in outdoor air particulate matter samples and human exposure assessment

Exposure to benzotriazoles and benzothiazoles in Czech male population and its associations with biomarkers of liver function, serum lipids and oxidative stress

INTRODUCTION

Benzotriazoles and benzothiazoles (BTs) are high-production volume chemicals as well as widely distributed emerging pollutants with potential health risk. However, information about human exposure to BTs and associated health outcomes is limited.

OBJECTIVE

We aimed to characterise exposure to BTs among Czech men, including possible occupational exposure among firefighters, its predictors, and its associations with liver function, serum lipids and oxidative stress.

METHODS

165 participants (including 110 firefighters) provided urine and blood samples that were used to quantify the urinary levels of 8 BTs (high-performance liquid chromatography-tandem mass spectrometry), and 4 liver enzymes, cholesterol, low-density lipoprotein, and 8-hydroxy-2'-deoxyguanosine. Linear regression was used to assess associations with population characteristics and biomarkers of liver function, serum lipids and oxidative stress. Regression models were adjusted for potential confounding variables and false discovery rate procedure was applied to account for multiplicity.

RESULTS

The BTs ranged from undetected up to 46.8 ng/mL. 2-hydroxy-benzothiazole was the most predominant compound (detection frequency 83%; median 1.95 ng/mL). 1-methyl-benzotriazole (1M-BTR) was measured in human samples for the first time, with a detection frequency 77% and median 1.75 ng/mL. Professional firefighters had lower urinary 1M-BTR compared to non-firefighters. Urinary 1M-BTR was associated with levels of γ-glutamyl transferase (β = - 17.54%; 95% CI: - 26.127, - 7.962).

CONCLUSION

This is the first study to investigate BT exposure in Central Europe, including potentially exposed firefighters. The findings showed a high prevalence of BTs in the study population, the relevance of 1M-BTR as a new biomarker of exposure, and an urgent need for further research into associated adverse health outcomes.

Comparing the Developmental Toxicity Delay and Neurotoxicity of Benzothiazole and Its Derivatives (BTHs) in Juvenile Zebrafish

In this study, a semi-static water exposure method was employed to investigate the early developmental and neurotoxic effects of four benzothiazole substances (BTHs), namely benzothiazole (BTH), 2-mercaptobenzothiazole (MBT), 2-hydroxybenzothiazole (BTON), and 2-aminobenzothiazole (2-ABTH), on zebrafish at an equimolar concentration of 10 μM. The findings revealed that all four BTHs exerted certain impacts on early development in zebrafish. MBT stimulated spontaneous movement in juvenile zebrafish, whereas BTON inhibited such movements. Moreover, all four BTHs hindered the hatching process of zebrafish larvae, with MBT exhibiting the strongest inhibition at 24 h post-fertilization (hpf). Notably, MBT acted as a melanin inhibitor by suppressing melanin production in juvenile zebrafish eyes and weakening phototaxis. Additionally, both BTH and BTON exhibited significantly lower speeds than the control group and other test groups under conditions without bright field stimulation; however, their speeds increased to average levels after percussion stimulation, indicating no significant alteration in motor ability among experimental zebrafish groups. Short-term exposure to these four types of BTHs induced oxidative damage in zebrafish larvae; specifically, BTH-, MBT-, and BTON-exposed groups displayed abnormal expression patterns of genes related to oxidative damage. Exposure to both BTH and MBT led to reduced fluorescence intensity in transgenic zebrafish labeled with central nervous system markers, suggesting inhibition of central nervous system development. Furthermore, real-time quantitative PCR results demonstrated abnormal gene expression associated with neural development. However, no significant changes were observed in 2-ABTH gene expression at this concentration. Overall findings indicate that short-term exposure to BTHs stimulates neurodevelopmental gene expression accompanied by oxidative damage.

Associations between urinary concentrations of benzothiazole, benzotriazole, and their derivatives and lung cancer: A nested case-control study

Benzothiazole (BTH), benzotriazole (BTR), and their respective derivatives (BTHs and BTRs) are emerging environmental pollutants with widespread human exposure and oncogenic potential. Studies have demonstrated adverse effects of exposure to certain BTHs and BTRs on the respiratory system. However, no study has examined the associations between exposure to BTHs and BTRs and lung cancer risk. We aimed to examine the associations between urinary concentrations of BTHs and BTRs and the risk of lung cancer in the general population from Quzhou, China. We conducted a nested case-control study in an ongoing prospective Quzhou Environmental Exposure and Human Health (QEEHH) cohort, involving 20, 694 participants who provided urine samples during April 2019-July 2020. With monthly follow-up until November 2022, 212 lung cancer cases were recruited and 1:1 matched with healthy controls based on age and sex. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) of lung cancer risk associated with urinary BTHs and BTRs concentrations using conditional logistic regression models after controlling for potential covariates. We also examined effect modification by several covariates, including sex, socioeconomic status, smoking status, alcohol consumption, and dietary habit. Creatinine-corrected urinary BTH and 2-hydroxy-benzothiazole (2-OH-BTH) levels were significantly associated with the risk of lung cancer, after adjusting for a variety of covariates. Participants in the highest quartile of BTH had a 95% higher risk of lung cancer, compared with those in the lowest quartile (adjusted OR = 1.95, 95% CI: 1.08-3.49; p for trend = 0.01). Participants with higher levels of urinary 2-OH-BTH had an 83% higher risk of lung cancer than those with lower levels (adjusted OR = 1.83, 95% CI: 1.16-2.88; p for trend = 0.01). Exposure to elevated levels of BTH and 2-OH-BTH may be associated with an increased risk of lung cancer. These associations were not modified by socio-demographic characteristics.

Occurrence of high production volume chemicals and polycyclic aromatic hydrocarbons in urban sites close to industrial areas. Human exposure and risk assessment

Evaluating the occurrence of high production volume chemicals (HPVCs) and polycyclic aromatic hydrocarbons (PAHs) in the air is important because they carry a carcinogenic risk and can lead to respiratory or endocrine problems. Examples of HPVCs are organophosphate esters, benzosulfonamides, benzothiazoles, phthalate esters (PAEs), phenolic antioxidants and ultraviolet stabilizers. In this paper we develop a multi-residue method for determining HPVCs and PAHs in air samples via pressurized liquid extraction followed by gas chromatography-mass spectrometry. Air samples were collected by active sampling with high volume samplers using quartz fiber filter for the particulate matter (PM10) and polyurethane foams for gas phase. The compounds found at the highest concentrations were PAEs, with a concentration of up to 24 ng m-3 of DEHP in gas phase and up to 109 ng m-3 of DEHA in PM10. Non-carcinogenic risk assessment results ranged from 9.7E-05 to 9.5E-03 for most of the compounds studied. On the other hand, the results for carcinogenic risk showed that PAHs made the highest contribution.

Impact of black soot emissions on public health in Niger Delta, Nigeria: understanding the severity of the problem

Rivers State, Niger Delta, Nigeria often referred to as the 'treasure bed of the nation' is the seat of crude oil production activities with the accompanying environmental degradation. The severity of the environmental pollution and contaminated air quality took a new turn for the worse in November 2016, when the residents of Port Harcourt city, Rivers State, a major oil producing State experienced for the first time, aerosol deposition of plumes of black soot. This systematic review paper is aimed at quantifying the severity of this public health challenge. Using appropriate search words, the following databases SCOPUS, PUBMED, Google Scholar, and AJOL were searched from 1990 to 2022 to enable comparative analyses of data before and after the emergence of black soot deposition. Air-related morbidities and mortalities such as cerebrospinal meningitis (CSM), chronic bronchitis, measles, pertussis, hemoptysis, cough, pulmonary tuberculosis, pneumonia, and upper respiratory tract infection (URTI), pneumonia, eye irritation, conjunctivitis, traumatic skin outgrowth, cancers, cardiovascular diseases, and child deformities were compared with levels of air pollutants and particulate matter. The results showed that Port Harcourt city's ambient air quality data were above the standard National Ambient Air Quality data and that of other regulatory agencies having higher levels of both inorganic and organic pollutants. There were significant relationships between air pollutants concentration with morbidities. These correlations were significant in the period covering 2016-2022. Consequently, it is concluded that the black soot emissions in Port Harcourt city, Nigeria has worsened the public health situation in the city.

Benzotriazole UV stabilizers (BUVs) as an emerging contaminant of concern: a review

Benzotriazole UV stabilizers (BUVs) are a group of industrial chemicals used in various consumer products and industrial applications. Due to its large-scale production and use, BUVs have been detected in all environmental matrices. Humans are exposed to BUVs from environmental media, food, personal care products (PCPs), and consumer products. As a result, BUVs are detected in human breast milk, attracting researchers and regulatory bodies worldwide. BUVs such as UV-328 exhibit the characteristics of persistent organic pollutants (POPs); hence, it has been recently listed under Stockholm Convention POP list. The current review focuses on the occurrence of BUVs in the environment with emphasis on persistency, bioaccumulation, and toxicity (PBT). Scarcity of scientific data on BUVs' properties, environmental occurrence, exposure levels, and effects on organisms poses significant challenges to the policymakers and regulatory bodies in adopting management strategies. The need for a science-based integrated framework for risk assessment and management of BUVs is recommended. Considering the potential threat of BUVs to human health and the environment, it is recommended that BUVs should be taken as a subject of priority research. Studies on the degradation and transformation route of BUVs need to be explored for the sound management of BUVs.

Removal of benzotriazole derivatives by biochar: Potential environmental applications

Benzotriazole and its derivatives (BTAs) are commonly present in wastewater due to their extensive use in industrial processes, yet their removal is still unexplored. Here, we test the removal of these pollutants using two functionalised biochars, synthesised from wild plum (WpOH) and apricot (AsPhA) kernels. The aim of this work was to optimise the adsorption process against various BTAs (i.e., benzotriazole (BTZ), 4-hydroxy-1H-benzotriazole (OHBZ), 4-methyl-1H-benzotriazole (4 MBZ), 5-methyl-1H-benzotriazole (5 MBZ), 5-chloro-1H-benzotriazole (ClBZ), 5,6-dimethyl-1H-benzotriazole (DMBZ)), and determine the adsorption mechanisms at play, using real wastewater matrices. Batch studies showed that the optimal adsorption pH ranged between 4 and 6 for WpOH and AsPhA, respectively, and equilibrium was reached after 240 min. The kinetic models that best described the adsorption process were in the following order: Elovich model > pseudo-second order model > pseudo-first order model. The equilibrium data showed the highest correlation with the Freundlich isotherm, indicating multilayer adsorption. The maximum adsorption capacity obtained in mixtures was 379 mg/g on WpOH and 526 mg/g on AsPhA. The mechanistic work revealed that the BTAs became bound to the biochar primarily through H-bonding, n-π and π-π EDA interactions. In wastewater, obtained before and after conventional treatment, the concentration of OHBZ and BTZ was reduced by >40%, while the concentration of the other compounds studied fell below the detection limit (∼2.0-90 ng/L). Finally, using a Vibrio fischeri assay, we showed that adsorption onto AsPhA significantly reduced the relative toxicity of both raw and treated wastewater.

Contaminants of emerging concern in urine: a review of analytical methods for determining diisocyanates, benzotriazoles, benzothiazoles, 4-methylbenzylidene camphor, isothiazolinones, fragrances, and non-phthalate plasticizers

Human biomonitoring (HBM) frameworks assess human exposure to hazardous chemicals. In this review, we discuss and summarize sample preparation procedures and analytical methodology for six groups of chemicals of emerging concern (CECs), namely diisocyanates, benzotriazoles, benzothiazoles, 4-methylbenzylidene camphor, isothiazolinones, fragrances, and non-phthalate plasticizers, which are increasingly detected in urine, however, are not yet widely included in HBM schemes, despite posing a risk to human health. The sample preparation procedures depend largely on the chemical group; however, solid-phase extraction (SPE) is most often used due to the minimized sample handling, lower sample volume, and generally achieving lower limits of quantification (LOQs) compared to other extraction techniques. In terms of sample analysis, LC-based methods generally achieve lower limits of quantification (LOQs) compared to GC-based methods for the selected six groups of chemicals owing to their broader chemical coverage. In conclusion, since these chemicals are expected to be more frequently included in future HBM studies, it becomes evident that there is a pressing need for rigorous quality assurance programs to ensure better comparability of data. These programs should include the reporting of measurement uncertainty and facilitate inter-laboratory comparisons among the reporting laboratories. In addition, high-resolution mass spectrometry should be more commonly employed to enhance the specificity and selectivity of the applied analytical methodology since it is underrepresented in HBM. Furthermore, due to the scarcity of data on the levels of these CECs in urine, large population HBM studies are necessary to gain a deeper understanding of the associated risks.

Removal of benzotriazole micropollutants using Spirodela polyrhiza (L.) Schleid. And Azolla caroliniana Willd

Phytoremediation of benzotriazoles (BTR) from waters by floating macrophytes is not well understood, but it seems to have the potential to be used in conjunction with conventional wastewater treatment plants. The effectiveness of removing four compounds from the benzotriazole group by floating plants Spirodela polyrhiza (L.) Schleid. And Azolla caroliniana Willd. From the model solution, was studied. The observed decrease in the concentration of studied compounds was in the range 70.5%-94.5% using S. polyrhiza, and from 88.3% to 96.2% for A. caroliniana. It was determined using chemometric methods that the effectiveness of the phytoremediation process is mainly influenced by three parameters: exposure time to light, pH of the model solution and the mass of plants. Using the design of experiments (DoE) chemometric approach, the optimal conditions for removing BTR were selected: plant weight 2.5 g and 2 g, light exposure 16 h and 10 h, and pH 9 and pH 5 for S. polyrhiza and A. caroliniana, respectively. Studies on the mechanisms of BTR removal have shown that the reduction in concentration is mainly due to the process of plant uptake. Toxicity studies have proved that the tested BTR affected the growth of S. polyrhiza and A. caroliniana and induced changes in the levels of chlorophyllides, chlorophylls as well as carotenoids. More dramatic loss in plant biomass and photosynthetic pigment contents was observed in A. caroliniana cultures exposed to BTR.

Chemical composition and potential health risks of tire and road wear microplastics from light-duty vehicles in an urban tunnel in China

Tire and road wear microplastics (TRWMPs) are one of the main non-exhaust pollutants of motor vehicles, which cause serious environmental and health issues. Here, TRWMPs in PM_2.5 samples were collected in a tunnel in urban Xi'an, northwest China, during four periods [I: 7:30-10:30, II: 11:00-14:00, III: 16:30-19:30, IV: 20:00-23:00 local standard time (LST)] in summer of 2019. The chemical components of rubbers, benzothiazoles, phthalates, and amines in TRWMPs were quantified, with a total concentration of 6522 ± 1455 ng m^-3 (mean ± standard deviation). Phthalates were predominant in TRWMPs, accounting for 64.8% on average, followed by rubbers (33.2%) and benzothiazoles (1.19%). The diurnal variations of TRWMPs showed the highest concentration in Period III (evening rush hour) and the lowest concentration in Period I (morning rush hour), which were not exactly consistent with the variation of the number of light-duty vehicles passed through the tunnel. The result implied that the number of vehicles might not be the most important contributor to TRWMPs concentration, whereas meteorological variables (i.e., precipitation, and relative humidity), vehicle speed, vehicle class, and road cleaning also affected their abundances. The non-carcinogenic risk of TRWMPs in this study was within the international safety threshold, but their carcinogenic risk exceeded the threshold by 2.7-4.6 times, mostly dominated by bis(2-ethylhexyl)phthalate (DEHP). This study provides a new basis for the source apportionment of urban PM_2.5 in China. The high concentrations and high potential cancer risks of TRWMPs represent the requirement for more efficient measures to control light-duty vehicle emissions.

Extraction of selected benzothiazoles, benzotriazoles and benzenesulfonamides from environmental water samples using a home-made sol-gel silica-based mixed-mode zwitterionic sorbent modified with graphene

A novel sol-gel silica-based mixed-mode zwitterionic sorbent modified with graphene microparticles was synthesized. Thanks to the inclusion of multiple functional groups and graphene microparticles to exert a wide range of intermolecular/interionic interactions including dipole-dipole interactions, ion-exchange interactions and π-π interactions, the sorbent showed high retention in the solid-phase extraction (SPE) of benzothiazoles, benzotriazoles and benzenesulfonamides. The SPE protocol was optimized in terms of pH, sample loading volume and elution conditions using liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS). The method based on SPE followed by LC-HRMS was validated. Apparent recoveries at two levels of concentration were in the range from 48 to 85% (in most cases) in matrices such as influent wastewater, matrix effect was lower than ±30% in most cases, method detection and quantification limits being lower than 20 ng/L and repeatability and reproducibility between days were lower than 18% (n = 4). River, effluent and influent wastewaters samples were analyzed, obtaining concentrations ranging from 3 to 175 ng/L in river samples, from 12 to 499 ng/L in effluent samples and from 15 to 632 ng/L in influent samples, when the compounds were above the method quantification limits.

Assessment of benzothiazoles, benzotriazoles and benzenesulfonamides in environmental waters using an optimized combination of microextraction by packed sorbent with programmed temperature vaporization-gas chromatography tandem-mass spectrometry

This work proposes a new method for the quantification of benzothiazoles (BTs), benzotriazoles (BTRs), and benzenesulfonamides (BSAs) in tap water, river water, and wastewater. The protocol involved the use of microextraction by packed sorbent (MEPS), applied for the first time for the extraction of the target analytes, combined with programmed temperature vaporization-gas chromatography-triple quadrupole mass spectrometry (PTV-GC-QqQ-MS). Considering the synergism between MEPS extraction and PTV injection, the experimental variables affecting their performance were simultaneously optimized by "experimental design", while principal component analysis (PCA) was used to find the overall optimal working conditions. Response surface methodology was used to gain a comprehensive understanding of the effects of working variables on method performance. The developed method achieved very good linearities and satisfactory intra- and inter-day accuracies and precisions. The protocol permitted the detection of the target molecules with limit of detection (LODs) values between 0.005 and 0.85 μg/L. The green character of the procedure was evaluated using three metrics: "Analytical Eco-Scale", "Green Analytical Procedure Index" (GAPI), and "Analytical Greenness metric for sample preparation (AGREEprep). The satisfactory results obtained with real water samples demonstrate the applicability of the method for monitoring campaigns and exposome studies.

The Road to Sustainable Tire Materials: Current State-of-the-Art and Future Prospectives

The development of a 100% sustainable tire has emerged as a milestone for several tire companies across the globe. It has created new commercial opportunities for the biobased, renewable, and recycled polymer materials. However, there are concerns that the incorporation of such sustainable new materials may have an undesirable impact on the main performance properties of the tire. At the same time, with new capabilities and product innovations, it can help us meet society's need in a more sustainable fashion and protect the environment. This Feature first outlines the opportunities and need for sustainable tire materials. Next, it describes the main types of sustainable material attributes in tire material, elastomers, reinforcing agents, fibers, and plasticizers, among a few others. The challenges to achieving the performance properties are discussed with possible design guidelines. Recent approaches to the tire attributes are described in the form of a meticulous overview of the existing literature, with a critical analysis of some of them. This contribution attempts to highlight, in a comprehensive way, sustainable tire materials on the basis of recent research advancements, existing challenges, and prospective future scope in this field.

Suspect Screening of Chemicals in Hospital Wastewaters Using Effect-Directed Analysis Approach as Prioritization Strategy

The increasing number of contaminants in the environment has pushed water monitoring programs to find out the most hazardous known and unknown chemicals in the environment. Sample treatment-simplification methods and non-target screening approaches can help researchers to not overlook potential chemicals present in complex aqueous samples. In this work, an effect-directed analysis (EDA) protocol using the sea urchin embryo test (SET) as a toxicological in vivo bioassay was used as simplified strategy to identify potential unknown chemicals present in a very complex aqueous matrix such as hospital effluent. The SET bioassay was used for the first time here to evaluate potential toxic fractions in hospital effluent, which were obtained after a two-step fractionation using C₁₈ and aminopropyl chromatographic semi-preparative columns. The unknown compounds present in the toxic fractions were identified by means of liquid chromatography coupled to a Q Exactive Orbitrap high-resolution mass spectrometer (LC-HRMS) and using a suspect analysis approach. The results were complemented by gas chromatography-mass spectrometry analysis (GC-MS) in order to identify the widest range of chemical compounds present in the sample and the toxic fractions. Using EDA as sample treatment simplification method, the number of unknown chemicals (>446 features) detected in the raw sample was narrowed down to 94 potential toxic candidates identified in the significantly toxic fractions. Among them, the presence of 25 compounds was confirmed with available chemical standards including 14 pharmaceuticals, a personal care product, six pesticides and four industrial products. The observations found in this work emphasize the difficulties in identifying potential toxicity drivers in complex water samples, as in the case of hospital wastewater.

Quantitative assessment of additive leachates in abiotic weathered tire cryogrinds and its application to tire wear particles in roadside soil samples

Tire and road wear particles (TRWP) are becoming an important research question with potential risks on ecological system. A comprehensive understanding of their detection and quantification in soils are challenged by the inherent technological inconsistencies, lack of well-set standardized methods, and generalized protocols. Reference tire cryogrinds were subjected to abiotic weathering. Next, the total environmental availability from parent elastomers and the release of additives from tire tread compounds were evaluated using mass concentration factors obtained from abiotic weathered tire cryogrinds. Headspace Gas chromatography-mass spectroscopy (HS-GC-MS) was employed as a nontargeted, suspect screening analysis technique to identify the tire related intermediates. Benzothiazole, 1,2-dihydro-2,2,4-trimethylquinoline (TMQ), aniline, phenol and benzoic acid were detected as tire tetrahydrofuran leachates. Total environmental availability of TMQ and benzothiazole were in the range of 1.7 × 10-3 and 0.11, respectively. Benzene and benzoic acid derivatives were identified as marker compounds for environmental samples. A TRWP content evaluation was made possible by quantifying marker concentrations and reference tire cryogrind formulation. TRWP content in the size range of 1-5 mm was between 800 and 1300 μg/g and 1200-3100 μg/g TRWP in Ohio and Kansas soil. For TRWP less than 1 mm, 0.15-2.1 wt% content was observed in Kansas and Ohio samples and were seemingly dependent on the locations and the traffic. This simple, widely applicable quantification method for TRWP analysis provides a database of tire degradation and TRWP intermediates. The TRWP content research is critical for further TRWP research development in terrestrial environment.

Occurrence of organic contaminants bonded to the particulate matter from outdoor air influenced by industrial activities

This paper discusses the occurrence of organic contaminants bonded to particulate matter (PM) in ambient air. We describe the presence and concentration levels of contaminants mainly reported in atmospheres close to factories or at locations influenced by them, and the relationship between factory emissions and the type of organic contaminants found in PM samples from the surrounding air. Many organic contaminants have been found in these types of samples, including polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs). Their sources, fates and distributions in the ambient atmosphere are therefore well known. However, in addition to these most studied compounds, others are also of concern nowadays due to their detection and toxic effects on the environment. The continuous updating of regulations on these contaminants and the appearance of new air pollutants make it important to be aware of their occurrence. This will help to either establish new guidelines for the newer contaminants or reassess existing limitations for known ones. Moreover, if we know their occurrence, we can analyse their sources, destinations and distributions in the outdoor air.

Associations of benzotriazoles and benzothiazoles with estrogens and androgens among pregnant women: A cohort study with repeated measurements

People are extensively exposed to benzotriazoles (BTRs) and benzothiazoles (BTHs) derivatives, which are environmental pollutants that may possess endocrine-disrupting potential; however, no epidemiological evidence is available on the associations of BTRs and BTHs with estrogens and androgens. This study aimed at investigating the associations of BTRs and BTHs with estrogens and androgens among pregnant women. Based on a prospective cohort study, we included 459 pregnant women who donated a complete serial of urine samples at each trimester and had repeated measurements of four BTRs, four BTHs, three estrogens (estrone, 17β-estradiol, and estrio), and two androgens (dehydroepiandrosterone and testosterone) in the urine samples. Associations of repeatedly measured BTRs and BTHs with maternal urinary estrogens and androgens were analyzed, and the cross-sectional associations were also analyzed. Tolyltriazole (TTR) (≥59.3%) and benzothiazole (BTH) (≥93.5%) had the highest detection rate among the BTRs and BTHs, respectively. Repeated measurement analysis and cross-sectional analysis consistently found the target BTRs and BTHs were positively associated with 17β-estradiol, estriol, and testosterone, while the trend of the associations with estrone and dehydroepiandrosterone was inconsistent. Among the positive associations with 17β-estradiol, estriol, and testosterone, the percent of change in estriol associated with TTR was the most prominent [28.5% (95% confidential interval: 24.2%, 32.9%) for each doubling in TTR]. The significant associations with estrone, estriol, testosterone, and dehydroepiandrosterone were stronger among pregnant women who gave birth to a boy than those who gave birth to a girl. These findings add epidemiological evidence on the endocrine-disrupting potential of BTRs and BTHs and highlight the importance of focusing on the health outcomes of BTRs and BTHs related to disturbed estrogens and androgens. Future studies are needed to validate these findings and explore the underlying mechanisms.

Method Development for Separation and Analysis of Tire and Road Wear Particles from Roadside Soil Samples

A comprehensive understanding of tire and road wear particles (TRWPs) and their detection and quantification in soils is still challenged by the lack of well-set standardized methods, inherent technological inconsistencies, and generalized protocols. Our protocol includes soil sampling, size separation, and organic matter removal by using hydrogen peroxide followed by density separation and analysis. In this context, roadside soil samples from different sites in Kansas and Ohio, USA, were collected and analyzed. Tire cryogrinds analogous to TRWPs were used to evaluate various density separation media, and collected particles more than 1 mm in size were then subjected to infrared spectroscopy (IR), thermogravimetric analysis (TGA), and scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDX) to confirm TRWP presence. Particles smaller than 1 mm were Soxhlet extracted, followed by gas chromatography-mass spectrometry (GC-MS) to validate the presence of tire-related intermediates. SEM-EDX validated the presence of elemental combinations (S + Zn/Na) ± (Al, Ca, Mg, K, Si) attributed to tires. Ketones, carboxylic acids, epoxies, cyclohexane, and benzothiazole sulfenamide (BTS) intermediates were the most probable tire-related intermediates observed in the roadside soil samples. Thus, this simple, widely applicable, cost-effective sample preparation protocol for TRWP analysis can assist TRWP research advancement in terrestrial environments.

The performance and pathway of benzothiazole degradation by electron beam irradiation

Benzothiazole (BTH) is a typical refractory heterocyclic compound that can be used as a photosensitive material in organic synthesis and conditional plant resource research. The extensive use of BTH has led to high BTH concentrations in natural environment, such as in tap water and urine, which tend to inhibit animal hormone synthesis and induce genotoxicity. Traditional wastewater treatment processes cannot effectively remove BTH. Therefore, we aimed to use the electron beam method, an emerging method for pollutant degradation, to degrade BTH in water. Experiments showed that BTH can be effectively degraded (up to 90%) when the electron beam reaches 5 kGy and irradiation conformed perfectly to the pseudo first-order kinetics model. Experimental results showed that acidic conditions are more favorable for electron beam degradation of BTH, while the degradation of most other inorganic ions is inhibited (except SO₄^2-). Hydroxyl radicals (•OH) was confirmed to play a major role in degradation by the experiment, and the mineralization rate was greatly increased by the addition of H₂O₂ and K₂S₂O₈. In addition, our experimental and theoretical calculations showed that the degradation of BTH occurred mainly through the opening of the benzene ring. Theoretical calculations showed that the toxicity of BTH decreased significantly after electron beam degradation, making it an effective way to degrade BTH.

Pollution characteristics, exposure assessment and potential cardiotoxicities of PM2.5-bound benzotriazole and its derivatives in typical Chinese cities

Benzotriazole and its derivatives (BTRs), classified as high-volume production chemicals, have been widely detected in various environmental media, including the atmosphere, water, soil and dust, as well as organisms. However, studies on the pollution characteristics and health impact of PM_2.5 related BTRs are so far limited. This study is the first to demonstrate the regional scale distribution of PM_2.5-bound BTRs and their potential cardiotoxicities. Optimized methods of extraction, purification and GC-EI-MS/MS were applied to characterize and analyze PM_2.5-bound BTRs from three cities in China during the winter of 2018. The concentration of ∑BTRs in Taiyuan (6.28 ng·m^-3) was more than three times that in Shanghai (1.53 ng·m^-3) and Guangzhou (1.99 ng·m^-3). Benzotriazole (BTR) and 5-methyl-1H-benzotriazole (5TTR) contributed more than 80% of ∑BTRs concentration as the major pollutants among three cities. The correlation analysis indicated that there was a positive correlation between temperature and concentration of BTR and a negative correlation between temperature and concentration of 5TTR. In addition, the risk of BTRs exposure to toddlers should be paid more attention in Taiyuan by the human exposure assessment. Furthermore, toxicity screening by experimental methods indicated that 4-methyl-1H-benzotriazole (4TTR) was the most harmful to cardiomyocytes. The western blot assay showed a ROS-mediated mitochondrial apoptosis signaling pathway was activated after exposure to 4TTR in neonatal rat cardiomyocytes (NRCMs). On the other hand, metabolomics revealed that exposure of 4TTR to NRCMs disturbed mitochondrial energy metabolism by disturbing pantothenate and coenzyme A synthesis pathway. Our study not only clarifies the contamination profiles of PM_2.5-bound BTRs in typical Chinese cities but also reveals their cardiotoxicities associated with mitochondrial dysfunction.

Development of an in vitro model to simulate migration of organic contaminants from pad products to human sweat and enhance dermal exposure risk assessment

Dermal sorption is an important route for human exposure to organic chemicals embedded in consumer products, but the related chemical migration from consumer products to sweats was often overlooked in assessing skin exposure risk. To address this issue, the present study selected polycyclic aromatic hydrocarbons (PAHs), phthalic acid esters (PAEs), and benzothiazoles (BTs) as the target compounds and developed an in vitro simulation model with two artificial sweats (i.e., acidic and alkaline), a sorbent, and a PVC standard material. An appropriate biological inhibitor (ampicillin) and incubation time of 20 d for assessing the maximum migration efficiency of chemicals were selected. The mass balance of the target compounds during the in vitro incubation was verified. The established in vitro simulation model was used to determine the migration ratios of PAEs and BTs in three types of mouse pads. The maximum migration ratios of DBP, DIBP, DEHP, and BT from leather pad to both sweats were less than those for silicone and rubber pads. Key controlling parameters in migration ratios should be examined in subsequent investigations. Risk assessment showed that the daily exposure doses of PAEs and BTs in mouse pads were higher than the literature data. The hazard index of PAEs in leather pad exceed 1, indicating that PAEs could induce non-carcinogenic effects to human health through hand contact. Overall, the established in vitro simulation model provides a feasible alternative for assessing the potential risk for dermal exposure to consumer products.

Trace Organic Contaminant Transfer and Transformation in Bioretention Cells: A Field Tracer Test with Benzotriazole

Bioretention cells can effectively infiltrate stormwater runoff and partly remove conventional water contaminants. A field tracer injection experiment in a conventionally designed bioretention cell was used to investigate the fate of benzotriazole, a model trace organic contaminant, during and between runoff events. Moderate (29%) benzotriazole load reductions were measured during the 6 h long injection experiment. The detection of 1-methyl benzotriazole, hydroxy benzotriazole, and methoxy benzotriazole provided in situ evidence of some rapid benzotriazole microbial transformation during the tracer test and more importantly between the events. The detection of benzotriazole alanine and benzotriazole acetyl alanine also showed fast benzotriazole phytotransformation to amino acid conjugates during the tracer test and suggests further transformation of phytotransformation products between events. These data provide conclusive full-scale evidence of benzotriazole microbial and phytotransformation in bioretention cells. Non-target chemical analysis revealed the presence of a diverse range of trace organic contaminants in urban runoff and exiting the bioretention cell, including pesticides and industrial, household, and pharmaceutical compounds. We have demonstrated the in situ potential of urban green infrastructure such as bioretention cells to eliminate polar trace organic contaminants from stormwater. However, targeted design and operation strategies, for example, hydraulic control and the use of soil amendments, should be incorporated for improved bioretention cell performance for such compounds.

An innovative green protocol for the quantification of benzothiazoles, benzotriazoles and benzosulfonamides in PM10 using microwave-assisted extraction coupled with solid-phase microextraction gas chromatography tandem-mass spectrometry

Benzothiazoles (BTHs), benzotriazoles (BTRs), and benzenesulfonamides (BSAs) are chemicals used in several industrial and household applications. Despite these compounds are emerging pollutants, there is still a lack of information about their presence in outdoor air samples. In this paper, we developed a new method for the quantification of BTHs, BTRs, and BSAs in airborne particulate matter (PM₁₀). The extraction of fourteen analytes from PM₁₀ was accomplished by microwave-assisted extraction (MAE) using an environmentally friendly mixture of water and ethanol. SPME was used to analyze the target compounds from the MAE extract by gas chromatography-tandem mass spectrometry (SPME-GC-MS/MS), eliminating additional sample clean-up steps. The best working conditions for MAE and SPME were examined multivariately by experimental design techniques. The target compounds were quantified in selected reaction monitoring acquisition mode. The proposed method was carefully validated, and the achieved results were satisfactory in terms of linearity, lower limit of quantification (picograms per cubic meter), intra- and inter-day accuracy (81-118% and 82-114%, respectively), and precision (repeatability and reproducibility in the range 2.3-17% and 7.4-19%, respectively). The application in a real monitoring campaign showed that the developed protocol is a valuable and eco-friendly alternative to the methods proposed so far.

Anthropogenic contaminants in freshwater from the northern Antarctic Peninsula region

This study aimed to evaluate the presence of ultraviolet filters (UV-Fs), benzotriazoles, pyrethroids and per- and polyfluoroalkyl substances (PFASs) in freshwater and wastewater from the northern Antarctic Peninsula region. All water samples analyzed contained UV-Fs residues and high concentrations were detected in anthropogenic impacted sites (< LOD up to 1300 ng/L). Likewise, benzotriazoles were detected in all water samples (< LOQ-920 ng/L). Regarding suspended particulate matter, almost all UV-Fs and all benzotriazoles were measured at concentrations ranging from < LOQ to 33 µg/g dry weight. Pyrethroids were also detected (< LOQ-250 ng/L) and their presence implies the existence of a gateway to the Antarctica Peninsula from other regions. The data confirmed the presence of PFASs (< LOD-7500 ng/L) in this area, in agreement with previous studies. In light of these results, extended monitoring in Antarctica should be carried out to perform a reliable environmental risk assessment leading to propose recommendations to minimize the anthropic impact.

Contamination profiles and health impact of benzothiazole and its derivatives in PM2.5 in typical Chinese cities

Although benzothiazole and its derivatives (BTHs) are considered emerging contaminants in diverse environments and organisms, little information is available about their contamination profiles and health impact in ambient particles. In this study, an optimized method of ultrasound-assisted extraction coupled with the selected reaction monitoring (SRM) mode of GC-EI-MS/MS was applied to characterize and analyze PM_2.5-bound BTHs from three cities of China (Guangzhou, Shanghai, and Taiyuan) during the winter of 2018. The total BTH concentration (ΣBTHs) in PM_2.5 samples from the three cities decreased in the order of Guangzhou > Shanghai > Taiyuan, independently of the PM_2.5 concentration. Despite the large variation in concentration of ΣBTHs in PM_2.5, 2-hydroxybenzothiazole (OTH) was always the predominant compound among the PM_2.5-bound BTHs and accounted for 50-80% of total BTHs in the three regions. Results from human exposure assessment and toxicity screening indicated that the outdoor exposure risk of PM_2.5-bound BTHs in toddlers was much higher than in adults, especially for OTH. The developmental and reproduction toxicity of OTH was further explored in vivo and in vitro. Exposure of mouse embryonic stem cells (mESCs) to OTH for 48 h significantly increased the intracellular reactive oxygen species (ROS) and induced DNA damage and apoptosis via the functionally activating p53 expression. In addition, the growth and development of zebrafish embryos were found to be severely affected after OTH treatment. An overall metabolomics study was conducted on the exposed zebrafish larvae. The results indicated that exposure to OTH inhibited the phenylalanine hydroxylation reaction, which further increased the accumulation of toxic phenylpyruvate and acetylphenylalanine in zebrafish. These findings provide important insights into the contamination profiles of PM_2.5-bound BTHs and emphasize the health risk of OTH.

Multi-residue analysis of several high-production-volume chemicals present in the particulate matter from outdoor air. A preliminary human exposure estimation

A multi-residue method based on gas chromatography-mass spectrometry combined with pressurised liquid extraction was developed to determine seven organophosphate esters (OPEs), six phthalate esters (PAEs), four benzotriazoles (BTRs), five benzothiazoles (BTHs) and four benzenesulfonamides (BSAs) in particulate matter samples from outdoor air. All of these compounds are among the named high-production volume chemicals (HPVCs) and some of them have shown to be harmful to human, therefore they have been subject for legal regulation in order to control their production and usage. Under optimised conditions, high recovery values (>80%) and low detection limits (pg m-3) were obtained for most of the compounds with accuracy values between 83% and 118%. Some samples from two locations surrounded by different industry activities showed the widespread occurrence of all the PAEs, followed by some OPEs. Diethylhexyl phthalate (DEHP) was the most abundant compound with concentrations ranging from 1.9 to 97.7 ng m-3. With the concentrations found, estimated daily intakes through outdoor inhalation were calculated for each contaminant and for different population groups classified by age (infants, children and adults) in two possible exposure scenarios (low and high). Then, hazard quotients and carcinogenic risks were estimated for several compounds, those that had toxicological parameters available. This preliminary result showed no significant risks via ambient inhalation for the exposed population, however more research is needed to confirm the present results.

Benzotriazoles and benzothiazoles prevail in indoor dust from an E-waste dismantling area in South China: Elevated concentrations and implication for human exposure

In this study, 6 BTRs and 9 BTHs were detected in indoor dust samples collected from a typical e-waste dismantling area and adjacent residential areas, as well as from a control urban area. The median ∑BTRs (the total concentrations of BTRs) in e-waste dismantling workshop dust (3830 ng/g) was up to about 21 and 17 times higher than those in the local residential house dust (180 ng/g) and the control urban residential house dust (231 ng/g), respectively. Similarly, significantly higher ∑BTHs (the total concentrations of BTHs) were also found in indoor dust from e-waste workshops (median: 2070 ng/g; range: 590-4430 ng/g) compared to the local residential houses (823 ng/g; 268-3350 ng/g) and the control urban residential houses (930 ng/g; 400-3650 ng/g). These results indicate that e-waste dismantling activities contribute to considerable residues of BTRs and BTHs in indoor dust. Benzotriazole (BTR), benzothiazole (BTH) and 2-hydroxy-benzothiazole (2-OH-BTH) were identified as the predominant compounds across three types of dust samples, cumulatively representing over 80% of ∑BTs (the sum of ∑BTRs and ∑BTHs). The different applications of BTRs and BTHs in e-products were clarified based on correlations analysis. The estimated daily intakes (EDIs) of BTRs and BTHs through dust intake for occupational workers were much higher than those for local and urban residents, implying that a potentially high risk can be posed to occupational workers.

Short-term perinatal toxicity study in sprague Dawley rats with the plasticizer and emerging contaminant N-Butylbenzenesulfonamide

N-Butylbenzenesulfonamide (NBBS) is a plasticizer and emerging contaminant that has been detected in a wide array of environmental samples. There are very little toxicity data available with which to evaluate potential risk from exposure to NBBS or other structurally-related sulfonamide plasticizers. To address this knowledge gap, NBBS was selected by the National Toxicology Program for evaluation. The current short-term pre- and post-natal (perinatal) study aims to provide preliminary toxicity and gestational transfer data for NBBS. NBBS was administered via dosed feed at concentrations of 0, 625, 1250, 2500, 5000, and 10,000 ppm to time-mated Sprague Dawley (Hsd:Sprague Dawley SD®) rats from gestation day (GD) 6 through postnatal day (PND) 28. The high concentration of 10,000 ppm NBBS was overtly toxic to dams, and the group was removed on GD 17-18. Exposure to NBBS resulted in lower maternal weights during the gestational period in the 5000 and 10,000 ppm groups as compared to control weights. Dams also displayed lower weights in the lactational period, which resolved to control levels by PND 28. NBBS exposure did not affect pregnancy or littering parameters in F0 dams. However, pup survival was lower in the 5000 ppm group, and pup weights were dose-responsively lower than control pup weights with the difference expanding over the postnatal period. The lowest observed effect level (LOEL) based on significantly lower body weights was 5000 ppm NBBS for F0 dams and 2500 ppm NBBS for F1 pups. Preliminary data for NBBS levels indicated that the chemical was transferred from dams to offspring during the gestational period.

Occurrence and risk assessment of benzothiazole, benzotriazole and benzenesulfonamide derivatives in airborne particulate matter from an industrial area in Spain

In this study we monitored benzothiazole (BTHs), benzotriazole (BTRs) and benzenesulfonamide (BSAs) derivatives in airborne particulate matter from four sampling sites near the port of Tarragona (Spain) over a one-year period. To do so, we developed a method based on ultrasound-assisted solvent extraction (USAE) followed by gas chromatography-mass spectrometry (GC-MS). We also studied concentrations of NO₂ and airborne particulate matter (PM_2.5 and PM_coarse) for a year. Our results showed NO₂ and PM_2.5 concentrations below the maximum average values established by the Europen Directive 2008/50/EC in the zone under study. Moreover, NO₂ values are directly proportional to changes in weather conditions and traffic emissions, while PM_coarse and PM_2.5 concentrations do not follow a clear trend as these may be generated from multiple sources (loading and unloading activities and traffic emissions). Regarding BTHs, BTRs and BSAs concentrations in particulate matter, the compounds found at the highest concentrations were 1-H-benzothiazole, 2-methylbenzothiazole, 2-chlorobenzothiazole, 1-H-benzotriazole, 4-methyl-1-H-benzotriazole, 2-(methylthio)-benzothiazole, 5-methyl-1-H-benzotriazole and bromobenzenesulfonamide with average concentrations ranging from 0.19 to 1.54 ng m^-3 in PM_coarse and from 0.09 to 0.61 ng m^-3 in PM_2.5. The remaining compounds were below the method quantification limits (MQLs) or were undetected in the samples analysed. Health risk values associated with the inhalation of the studied compounds were between 1.80 × 10^-3 and 1.27 × 10^-2 in the worst-exposure scenario.

Early pregnancy exposure to benzotriazoles and benzothiazoles in relation to gestational diabetes mellitus: A prospective cohort study

BACKGROUND

Benzotriazoles (BTRs) and benzothiazoles (BTHs) are emerging contaminants with potential insulin modulation activities. Pregnancy exposure to BTs (BTRs and BTHs) may be a risk factor for the development of gestational diabetes mellitus (GDM). However, epidemiological studies are limited.

OBJECTIVES

We prospectively investigated the associations of exposure to BTs at early pregnancy with the blood glucose levels and the risks of GDM.

METHODS

A prospective cohort of 1770 pregnant women who were free of diabetes at baseline was established between 2013 and 2015 in Wuhan, China. Urine samples collected at 13.1 ± 1.1 weeks of gestation were analyzed to estimate the exposure level of BTs. The diagnosis of GDM was based on a 75 g oral glucose tolerance test (OGTT) conducted at 26.4 ± 2.4 weeks of gestation. We examined the associations between urinary concentration of BTs and blood glucose levels by linear regression models. The associations of urinary BTs concentrations with the relative risk (RR) of GDM were evaluated by generalized estimating equations with Poisson regression. Effect modifications by fetus sex and pre-pregnancy body mass index (BMI) were further evaluated in the sensitivity analysis.

RESULTS

A total of 147 (8.31%) pregnant women were diagnosed with GDM. Median concentrations of urinary BTs did not differ significantly between pregnant women with and without GDM. It was found that urinary levels of benzothiazole and 2-hydroxy-benzothiazole (2-OH-BTH) were positively associated with 2-hour blood glucose (p for trend < 0.050). Comparing the high exposure group with the low exposure group of 2-OH-BTH, the adjusted RR of GDM was 1.79 (95% CI = 1.18 to 2.69, p for trend = 0.012). Sensitivity analysis indicated that the positive association of the urinary 2-OH-BTH level with the RR of GDM remained significant among pregnant women who had a male fetus (RR = 1.76, 95% CI = 1.02 to 3.03, p for trend = 0.041) and those with a normal pre-pregnancy BMI (RR = 1.85, 95% CI = 1.09 to 3.11, p for trend = 0.034).

CONCLUSIONS

These findings suggested that higher urinary level of 2-OH-BTH in early pregnancy was associated with impaired glucose homeostasis and the increased risk of GDM. The results underscore the need of follow-up studies to validate the findings and elucidate the underlying biological mechanism.

Suspect and Nontarget Screening for Contaminants of Emerging Concern in an Urban Estuary

This study used suspect and nontarget screening with high-resolution mass spectrometry to characterize the occurrence of contaminants of emerging concern (CECs) in the nearshore marine environment of Puget Sound (WA). In total, 87 non-polymeric CECs were identified; those confirmed with reference standards (45) included pharmaceuticals, herbicides, vehicle-related compounds, plasticizers, and flame retardants. Eight polyfluoroalkyl substances were detected; perfluorooctanesulfonic acid (PFOS) concentrations were as high as 72-140 ng/L at one location. Low levels of methamphetamine were detected in 41% of the samples. Transformation products of pesticides were tentatively identified, including two novel transformation products of tebuthiuron. While a hydrodynamic simulation, analytical results, and dilution calculations demonstrated the prevalence of wastewater effluent to nearshore marine environments, the identity and abundance of selected CECs revealed the additional contributions from stormwater and localized urban and industrial sources. For the confirmed CECs, risk quotients were calculated based on concentrations and predicted toxicities, and eight CECs had risk quotients >1. Dilution in the marine estuarine environment lowered the risks of most wastewater-derived CECs, but dilution alone is insufficient to mitigate risks of localized inputs. These findings highlighted the necessity of suspect and nontarget screening and revealed the importance of localized contamination sources in urban marine environments.

Suspect and Nontargeted Strategies to Investigate in Vitro Human Biotransformation Products of Emerging Environmental Contaminants: The Benzotriazoles

Benzotriazole derivatives (BTRs) are high production volume chemicals involved in a wide range of applications and consumer products resulting in their ubiquitous presence in environmental matrices. Yet, the human exposure assessment to these chemicals is limited since it is based only on the analysis of parent compounds in biological matrices. The objective of this study was to investigate the in vitro human biotransformation for three widely used BTRs and to stepwise examine the role of Phase I and II enzymes (cytochrome P450 (CYP), uridine glucuronic acid transferase (UGT), and sulfotransferase (SULT)) in their biotransformation. Extracts with generated biotransformation products (bioTPs) were analyzed using liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS), followed by their identification based on a workflow combining suspect and nontargeted strategies. Ten bioTPs were identified for 1H-benzotriazole, 14 for tolyltriazole, and 14 for 5-chloro-1H-benzotriazole. Most of the proposed bioTPs were identified and structurally elucidated for the first time. Based on these findings, possible bioTPs and metabolic transformation pathways were subsequently predicted for other structurally close BTR derivatives. Our findings provide new identified in vitro biotransformation products for future biomonitoring studies and emphasize that it is important to investigate the biotransformation pathway to assess overall exposure to xenobiotics.

Occurrence of plastic additives in outdoor air particulate matters from two industrial parks of Tarragona, Spain: Human inhalation intake risk assessment

Plastic additives include several kinds of chemicals that are added to the polymer matrix to improve the final product quality and prevent deterioration effects. They are used in a large quantity of materials, so their presence in the environment is expected. This study has developed and validated a method based on gas chromatography-mass spectrometry after pressurised liquid extraction to determine sixteen plastic additives including UV-stabilizers, aromatic and phenolic antioxidants and some of their degradation products in particulate matter (PM₁₀) from outdoor air. Apparent recoveries were above 85% for most of compounds and low detection limits (pg m^-3) were achieved. This is the first study to determine these types of contaminant in the PM₁₀ of outdoor air from two locations surrounded by different industries. Various compounds were found in almost all samples; BHT, BHT-Q, 2,4-DTBP, BHT-CHO, UV320, UV328, Irgafos168 and Iragonx1076, with concentrations ranging from < MQL to 2860 pg m^-3. Estimated daily intakes (EDIs) via ambient inhalation were calculated for each polymer additive and for different subpopulation groups classified by age. Two possible exposure scenarios (low, based on geometric mean, and high, 95th percentile) were simulated, and 0.51 ng kg_bw^-1 day^-1 was the EDI in the worst case scenario for children.

Occurrence, toxicity and transformation of six typical benzotriazoles in the environment: A review

Benzotriazoles (BTs) are a group of heterocyclic compounds which have been widely applied in industrial activities and domestic life mainly as corrosive inhibitors. BTs have been ubiquitously detected in receiving environments and cause potential toxicity to non-target organisms. This paper reviews the occurrence and fate of six selected benzotriazole compounds in different environmental and biological matrices, as well as the transformation and toxicity. Due to their high hydrophilicity and insufficient removal in wastewater treatment plants (WWTPs), these compounds were widely detected in aquatic environments with concentrations mainly from tens ng/L to tens μg/L. Considerable residual levels of BTs in plant, fish, air, tap water and human urine have implied the potential risks to various organsims. The reported acute toxicity of BTs are generally low (EC₅₀ in mg/L level). Some observed sublethal effects including endocrine disrupting effects, hepatotoxicity and neurotoxicity, as well as the ability to promote the development of endometrial carcinoma still raise a concern. BTs are found often more recalcitrant to biodegradation compared to photolysis and ozonation. Environmental factors including pH, temperature, irradiation wavelength, redox condition as well as components of matrix are proved crucial to the removal of BTs. Further studies are needed to explore the precise environment fate and toxicity mechanism of BTs, and develop advanced treatment technologies to reduce the potential ecological risks of BTs.