Tris(2-butoxyethyl) Phosphate Research Articles

Pollution characteristics and risk assessment of organophosphate esters (OPEs) in typical industrial parks in Southwest China.

As alternative substances of PBDEs, organophosphate esters (OPEs), an emerging organic pollutant, were increasingly produced and used in many kinds of industries and consumer products. However, OPEs also have various adverse toxic effects. Information on the pollution levels and exposure to OPEs in related industries is still limited. This study presented data on OPE contamination in the soil, leaf, and river water samples from seven typical industrial parks in Southwest China. Total concentration of seven OPEs (Σ7OPE) including tri-n-butyl phosphate (TnBP), tris-(2-ethylhexyl) phosphate (TEHP), tris-(2-butoxyethyl) phosphate (TBEP), tris-(2-carboxyethyl) phosphine (TCEP), triphenyl phosphate (TPhP), tris-(1,3-dichloro-2-propyl) ester (TDCPP), and tris-(chlorisopropyl) phosphate (TCPP) in the soil samples (36.2 ~ 219.7 ng/g) and the surrounding river water samples (118.9 ~ 287.7 ng/L) were mostly lower than those in other studies, while the Σ7OPE level in the leaves (2053.3 ~ 8152.7 ng/g) was relatively high. There were significant differences in the concentration and distribution of OPEs in the surrounding environment of different industrial parks. TDCPP, TnBP, and TCPP could be used as the characteristic compound in soil samples from auto industrial park, river samples from shoe making industrial park, and leaf samples from logistics park, respectively. The parameter m (the content ratio of chlorinated OPEs to alkyl OPEs) was suggested to distinguish the types of industrial park preliminary. When m ≥ 1, it mainly refers to heavy industries sources such as automobiles, electronics, and machinery, etc. When m<1, it mainly for the light industrial sources such as textile industry, transportation services, and resources processing, etc. For logistics park, furniture park and Wuhou comprehensive industrial park, the volatilization of materials was the main sources of OPEs in the surrounding environment, while more effort was required to strengthen the pollution control and management of the waste water and soil in the pharmacy industrial park, shoe making industrial park and auto industrial park. Risk assessment showed that there was a negligible non-cancer and carcinogenic risk in the soil, while high attention should be paid to the non-cancer risk for children.

Global responses to tris(1-chloro-2-propyl) phosphate and tris(2-butoxyethyl) phosphate in Escherichia coli: Evidences from biomarkers, and metabolic disturbance using GC-MS and LC-MS metabolomics analyses

Tris(1-chloro-2-propyl) phosphate (TCPP) and tris(2-butoxyethyl) phosphate (TBEP) as pollutants of emerging concern have aroused the rising attention due to their potential risks on aquatic ecosystem and public health. Nevertheless, there is a lack of toxicological mechanisms exploration of TCPP and TBEP at molecular levels. Herein, the toxicity effects and molecular mechanism of them were fully researched and summarized on Escherichia coli (E.coli). Acute exposure to them significantly activated antioxidant defense system and caused lipid peroxidation, as proved by the changes of antioxidant enzymes and MDA. The ROS overload resulted in the drop of membrane potential as well as the downregulated synthesis of ATPase, endorsing that E. coli cytotoxicity was ascribed to oxidative stress damage induced by TCPP and TBEP. The combination of GC-MS and LC-MS based metabolomics validated that TCPP and TBEP induced metabolic reprogramming in E.coli. More specifically, the responsive metabolites in carbohydrate metabolism, lipids metabolism, nucleotide metabolism, amino acid metabolism, and organic acids metabolism were significantly disturbed by TCPP and TBEP, confirming the negative effects on metabolic functions and key bioprocesses. Additionally, several biomarkers including PE(16:1(5Z)/15:0), PA(17:1(9Z)/18:2(9Z,12Z)), PE(19:1(9Z)/0:0), and LysoPE(0:0/18:1(11Z)) were remarkably upregulated, verifying that the protection of cellular membrane was conducted by regulating the expression of lipids-associated metabolites. Collectively, this work sheds new light on the potential molecular toxicity mechanism of TCPP and TBEP on aquatic organisms, and these findings using GC-MS and LC-MS metabolomics generate a fresh insight into assessing the effects of OPFRs on target and non-target aquatic organisms.

Prenatal organophosphate esters exposure and neurodevelopment trajectory in infancy: Evidence from the Shanghai Maternal-Child Pairs Cohort

BackgroundConcerns remain about the neurotoxic properties of the ubiquitous organophosphate esters (OPEs), the replacement of the toxicant polybrominated diphenyl ethers. ObjectivesWe examined the associations of prenatal exposure to OPEs and their mixtures with early-life neurodevelopment trajectories. MethodsTotally 1276 mother-child pairs were recruited from the Shanghai Maternal-Child Pairs Cohort. A high-performance liquid chromatography-triple quadrupole mass spectrometer was used to measure the levels of 7 OPEs in cord serum. Ages and Stages Questionnaires was used to examine children's neuropsychological development at 2, 6, 12, and 24 months of age. Group-based trajectory models were applied to derive the neurodevelopmental trajectories. Multiple linear regression and logistic regression model were performed to assess the relationships between OPEs exposure and neurodevelopment and trajectories. Mixtures for widely detected OPEs (n = 4) were investigated using quantile-based g-computation. ResultsTributyl phosphate (TBP), tris (2-butoxy ethyl) phosphate (TBEP), tris(1,3-dichloro-2-propyl) phosphate (TDCPP), and 2-ethylhexyl diphenyl phosphate (EHDPP), had detection rates >50 %. TDCPP had the highest median concentration (1.02 μg/L) in cord serum. EHDPP concentrations were negatively associated with scores in most domains at 12 months of age, with effect values (β) ranging from −1.89 to −0.57. EHDPP could negatively affect the total ASQ (OR = 1.07, 95 % CI: 1, 1.15) and gross-motor (OR = 1.09, 95 % CI: 1.02, 1.17) trajectory in infancy. Joint exposure to OPEs was associated with decreased scores in the total ASQ, gross-motor, fine-motor and problem-solving domain of 12-month-old infants, with β ranging from −5.93 to −1.25. In addition, the qgcomp models indicated significant positive associations between the concentrations of OPEs mixtures and risks of the persistently low group of the total ASQ, gross-motor and fine-motor development in early childhood. The impact of OPEs was more pronounced in boys. DiscussionOur findings suggested OPEs, especially EHDPP, had a persistently negative effect on neurodevelopment during the first 2 years.

Personal environmental exposure to plasticizers and organophosphate flame retardants using silicone wristbands and urine: Patterns, comparisons, and correlations

Plasticizers (PLs) and organophosphate flame retardants (OPFRs) are ubiquitous in the environment due to their widespread use and potential for leaching from consumer products. Environmental exposure is a critical aspect of the human exposome, revealing complex interactions between environmental contaminants and potential health effects. Silicone wristbands (SWBs) have emerged as a novel and non-invasive sampling device for assessing personal external exposure. In this study, SWBs were used as a proxy to estimate personal dermal adsorption (EDdermal) to PLs and OPFRs in Belgian participants for one week; four morning urine samples were also collected and analyzed for estimated daily intake (EDI). The results of the SWBs samples showed that all the participants were exposed to these chemicals, and the exposure was found to be highest for the legacy and alternative plasticizers (LP and AP), followed by the legacy and emerging OPFRs (LOPFR and EOPFR). In urine samples, the highest levels were observed for metabolites of diethyl phthalate (DEP), di-isobutyl phthalate (DiBP) and di-n-butyl phthalate (DnBP) among LPs and di(2-ethylhexyl) terephthalate (DEHT) for APs. Outliers among the participants indicated that there were other sources of exposure that were not identified. Results showed a significant correlation between EDdermal and EDI for DiBP, tris (2-butoxyethyl) phosphate (TBOEP) and triphenyl phosphate (TPhP). These correlations indicated their suitability for predicting exposure via SWB monitoring for total chemical exposure. The results of this pilot study advance our understanding of SWB sampling and its relevance for predicting aggregate environmental chemical exposures, while highlighting the potential of SWBs as low-cost, non-invasive personal samplers for future research. This innovative approach has the potential to advance the assessment of environmental exposures and their impact on public health.

Novel method for rapid monitoring of OPFRs by LLE and GC–MS as a tool for assessing biodegradation: validation and applicability

Organophosphate flame retardants (OPFRs) are high-production volume chemicals widely present in environmental compartments. The presence of water-soluble OPFRs (tri-n-butyl phosphate (TnBP), tris(2-butoxyethyl) phosphate (TBEP), tris(2-chloroethyl) phosphate (TCEP), tris(2-chloroisopropyl) phosphate (TCPP), and triethyl phosphate (TEP)) in water compartments evidences the struggle of conventional wastewater treatment plants (WWTPs) to effectively eliminate these toxic compounds. This study reports for the first time the use of white-rot fungi as a promising alternative for the removal of these OPFRs. To accomplish this, a simple and cost-efficient quantification method for rapid monitoring of these contaminants’ concentrations by GC–MS while accounting for matrix effects was developed. The method proved to be valid and reliable for all the tested parameters. Sample stability was examined under various storage conditions, showing the original samples to be stable after 60 days of freezing, while post-extraction storage techniques were also effective. Finally, a screening of fungal degraders while assessing the influence of the glucose regime on OPFR removal was performed. Longer chain organophosphate flame retardants, TBP and TBEP, could be easily and completely removed by the fungus Ganoderma lucidum after only 4 days. This fungus also stood out as the sole organism capable of partially degrading TCEP (35% removal). The other chlorinated compound, TCPP, was more easily degraded and 70% of its main isomer was removed by T. versicolor. However, chlorinated compounds were only partially degraded under nutrient-limiting conditions. TEP was either not degraded or poorly degraded, and it is likely that it is a transformation product from another OPFR’s degradation. These results suggest that degradation of chlorinated compounds is dependent on the concentration of the main carbon source and that more polar OPFRs are less susceptible to degradation, given that they are less accessible to radical removal by fungi. Overall, the findings of the present study pave the way for further planned research and a potential application for the degradation of these contaminants in real wastewaters.Graphical

Organophosphate esters in the urban atmosphere of Thessaloniki city, Greece

The occurrence of organophosphate esters (OPEs) in the atmosphere of the urban area of Thessaloniki city, Greece was studied. OPEs were determined in particulate matter (PM2.5) and precipitation during the period 2020–2021. ∑OPEs in rainwater ranged from 520 to 4719 ng L−11 (mean: 1662 ng L−1) with tris (2-butoxyethyl) phosphate (TBOEP) and tris (1-chloro-2-propyl) phosphate (TClPP) being the most abundant compounds. TBOEP and TClPP as well as triphenylphosphine oxide (TPPO) and tris (chloroethyl) phosphate (TCEP) were the dominant OPEs in PM2.5. Concentrations of ∑OPEs in PM2.5ranged from 2.82 to 13.3 ng m−3 (mean: 5.93 ng m−3). Wet deposition fluxes of OPEs were estimated and air mass back trajectories were used to elucidate possible source profiles. An overall low health risk for local population via inhalation of OPEs was revealed.

Characteristics, sources, bio-accessibility, and health risks of organophosphate esters in urban surface dust, soil, and dustfall in the arid city of Urumqi in China

Sixty-eight paired samples of urban surface dust and soil as well as four samples of atmospheric dustfall were collected from the arid city of Urumqi in Northwest China. Thirteen organophosphate esters (OPEs) in these samples were analyzed for the characteristics, sources, bio-accessibility, and health risks of OPEs. The studied OPEs were widely detected in the urban surface dust, soil, and dustfall, with Σ13OPEs (total concentration of 13 OPEs) of 1362, 164.0, and 1367 ng/g, respectively, dominated by tris(2-chloroethyle) phosphate (TCEP), tri(2-chloroisopropyl) phosphate (TCiPP), tri(1, 3-dichloroisopropyl) phosphate (TDCiPP) and tris(2-butoxyethyl) phosphate (TBOEP), TBOEP and tri(2-ethylhexyl) phosphate (TEHP), and TCEP, TCiPP, TBOEP, triphenyl phosphate and TEHP, respectively. The low and high frequency magnetic susceptibility of surface dust and urban soil might indicate the pollution of OPEs in them. Elevated levels of the Σ13OPEs in the surface dust and urban soil were found in the west, south, and northeast of Urumqi city. The total deposition flux of dustfall-bound 13 OPEs ranged from 86.5 to 143 ng/m2/day, with a mean of 105 ng/m2/day. OPEs in the surface dust and urban soil were associated with the emissions of indoor and outdoor products containing OPEs, the dry and wet deposition of atmosphere, and the emissions of traffic. Trimethyl phosphate, triethyl phosphate, tripropyl phosphate, tri-isobutyl phosphate, TCEP, TCiPP, TDCiPP, and TBOEP in surface dust and urban soil had relatively high bio-accessibility. The bio-accessibility of OPEs was mainly affected by the physio-chemical properties of OPEs. The non-cancer and cancer risks of human exposure to OPEs in surface dust and urban soil were relatively low or negligible. The current research results may provide scientific supports for prevention and control of pollution and risks of OPEs.

Occurrence, source apportionment, and ecological risk assessment of organophosphate esters in surface sediment from the Ogun and Osun Rivers, Southwest Nigeria

Organophosphate esters (OPEs) are synthetic chemicals widely used as e.g., flame retardants and plasticisers in various consumer products. Due to the toxicity of OPEs in aquatic ecosystems, exposure of fauna and flora to these compounds is of potential concern. In this study, the concentrations, profiles, sources, and ecological risk of eight OPEs were investigated in the sediments from the two major rivers in southwest Nigeria. Concentrations of ∑OPEs in surface sediments were in the range 13.1 – 2110 ng/g dry weight (dw) (median: 378 ng/g dw) in the Ogun River and 24.7—589 ng/g dw (median: 174 ng/g dw) in the Osun River. These concentrations are broadly within the range of those reported in surface sediment in previous studies conducted in other locations around the world. Tris (2-butoxyethyl) phosphate (TBOEP) was the dominant OPE in the sediment samples with a median concentration of 337 and 126 ng/g dw for the Ogun and Osun Rivers respectively, while tri-n-butyl phosphate (TnBP) was not detected in any sample. Excluding TBOEP, the chlorinated organophosphate esters: tris(2-chloroethyl) phosphate (TCEP), tris(2-chloro-propyl) phosphate (TCIPP), and tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) were the dominant OPEs in the Osun River, while the aryl-OPEs: triphenyl phosphate (TPHP), 2-ethylhexyl diphenyl phosphate (EHDPP), and tri-m-tolyl phosphate (TMTP) were dominant in the Ogun River. Under a median exposure scenario, moderate ecological risk was predicted from exposure to TCIPP in the Osun River. In contrast, under a high exposure scenario, concentrations of TDCIPP (risk quotient, RQ = 5.33—5.37) constituted a high ecological risk in both rivers, with moderate risks observed for TBOEP (RQ = 0.022—0.18) and TCIPP (RQ = 0.097 – 0.16). Therefore, the risk to aquatic organisms from concomitant exposure to mixtures of OPEs in freshwater ecosystems requires further investigation.Graphical

Organophosphorus flame retardants and their metabolites in paired human blood and urine

Organophosphorus flame retardants (OPFRs) have been shown to be carcinogenic, neurotoxic, and endocrine disruptive, so it is important to understand the levels of OPFRs in human body as well as the modes of external exposure. In this study, we investigated the levels of 13 OPFRs and 7 phosphodiester metabolites in paired human blood and urine, as well as the influencing factors (region, age and gender), and studied the relationship between OPFRs and oxidative stress by urinary metabolites. We found that the concentrations of triphenyl phosphate (TPhP) and tris-(2-ethylhexyl) phosphate (TEHP) in the blood of urban populations were higher than those of rural populations, and that younger populations suffered higher TPhP and 2-ethylhexyl diphenyl phosphate (EHDPP) exposures than older populations. In addition, we found that tris-(2-chloroethyl) phosphate (TCEP), tributyl phosphate (TnBP), TPhP and EHDPP exposure induced oxidative stress. The results of the internal load principal component analysis indicated that dust ingestion, skin exposure, respiration and dietary intake may be the most important sources of TCEP, tris(2-butoxyethyl) phosphate (TBOEP), tri(2-chloroisopropyl) phosphate (TCIPP) and TEHP, respectively, and dust ingestion and skin exposure may be the main sources of TPhP for humans.

Uptake mechanism, translocation, and transformation of organophosphate esters in water hyacinth (Eichhornia crassipes): A hydroponic study

Owing to their dominant wastewater origin, bioavailability, and toxicity, the occurrence and behavior of organophosphate esters (OPEs) in aquatic systems have attracted considerable attention over the past two decades. Aquatic plants can accumulate and metabolize OPEs in water, thereby playing an important role in their behavior and fate in waterbodies. However, their uptake, translocation and transformation mechanisms in plants remain incompletely characterized. We investigated the accumulation and transformation of OPEs in water hyacinth (Eichhornia crassipes) through a series of hydroponic experiments using three representative OPEs, tris(2-chloroethyl) phosphate (TCEP), tris(2-butoxyethyl) phosphate (TBEP), and triphenyl phosphate (TPP). These OPEs can not only be adsorbed onto and enter plant roots via passive diffusion pathways, which are facilitated by anion channels and/or aquaporins, but also can return to the solution when concentration gradients exist. After entry, hydrophilic TCEP showed a dominant distribution in the cell sap, strong acropetal transportability, and rapid translocation rate, whereas hydrophobic TPP was mostly retained in the root cell wall and therefore demonstrated weak acropetal transportability; TBEP with moderate hydrophilicity remained in the middle. All these OPEs can be transformed into diesters, which presented higher proportions in the cell sap and therefore have stronger acropetal transferability than their parent OPEs. TCEP exhibits the lowest biodegradability, followed by TPP and TBEP. These OPEs exerted apparent effects on plant growth, photosynthesis, and the diversity and composition of the rhizosphere microbial community.

Toxicological Mechanisms and Potencies of Organophosphate Esters in KGN Human Ovarian Granulosa Cells as Revealed by High-throughput Transcriptomics.

Despite the growing number of studies reporting potential risks associated with exposure to organophosphate esters (OPEs), their molecular mechanisms of action remain poorly defined. We used the high-throughput TempO-Seq™ platform to investigate the effects of frequently detected OPEs on the expression of ∼3000 environmentally responsive genes in KGN human ovarian granulosa cells. Cells were exposed for 48 h to one of five OPEs (0.1 to 50 μM): tris(methylphenyl) phosphate (TMPP), isopropylated triphenyl phosphate (IPPP), tert-butylphenyl diphenyl phosphate (BPDP), triphenyl phosphate (TPHP), or tris(2-butoxyethyl) phosphate (TBOEP). The sequencing data indicate that four OPEs induced transcriptional changes, whereas TBOEP had no effect within the concentration range tested. Multiple pathway databases were used to predict alterations in biological processes based on differentially expressed genes. At lower concentrations, inhibition of the cholesterol biosynthetic pathway was the predominant effect of OPEs; this was likely a consequence of intracellular cholesterol accumulation. At higher concentrations, BPDP and TPHP had distinct effects, primarily affecting pathways involved in cell cycle progression and other stress responses. Benchmark concentration (BMC) modelling revealed that BPDP had the lowest transcriptomic point of departure. However, in vitro to in vivo extrapolation modeling indicated that TMPP was bioactive at lower concentrations than the other OPEs. We conclude that these new approach methodologies provide information on the mechanism(s) underlying the effects of data-poor compounds and assist in the derivation of protective points of departure for use in chemical read-across and decision-making.

Atmosphere-Transported Emerging and Persistent Contaminants (EPCs) in Rainfall and Throughfall: Insights from a Rural Site in Northern Thailand

This study investigates the presence and concentrations of emerging and persistent contaminants (EPCs) in rainwater and throughfall water collected from urban areas and agricultural lands in northern Thailand. It focuses on one daily-use compound (caffeine), two industrial compounds (4-nitrophenol and tris(2-butoxyethyl) phosphate (TBEP)), and three agrichemicals (atrazine, fenobucarb, and 2,4-D). Additionally, information is provided regarding the presence of acetaminophen, fexofenadine, diphenhydramine, and gabapentin. Small differences in the chemical composition of the six main contaminants were observed between rainwater and forest throughfall water. However, significant variations were found in the concentration ranges of each EPC. In most cases, throughfall samples exhibited slightly higher concentrations, suggesting a limited contribution from dry deposition compared to rainfall. Limited reliable evidence was found concerning seasonal patterns in EPC concentrations in precipitation (rainfall and throughfall) and surface water samples in remote ponds and reservoirs. The transportation of EPCs via rainwater appears to vary among the compounds tested and is likely to vary from one rainfall event to another, rather than showing a strong and common seasonal response within the monsoon rainfall regime. These findings suggest that the transport of EPCs to remote areas via rainfall does occur for some EPCs. However, the dominance of this process over other transport mechanisms could not be determined with high confidence.

Occurrence and dietary exposure to organophosphorus esters in foodstuffs of Nigerian origin

Despite extensive evidence of the presence of organophosphate esters (OPEs) in various environmental matrices including foodstuffs in some developed countries, there are no data on the presence of OPEs in African foodstuffs. This study provides the first data on concentrations of OPEs in foods of Nigerian origin by measuring the concentrations of eight OPEs in 85 food items either purchased in Nigeria or from major African stores in Birmingham, UK. Foodstuffs analysed were divided into ten categories. Median concentrations of ∑8OPEs in melon (Egusi) (17.4 ng/g wet weight (ww)), cassava flour (Fufu) (11.6 ng/g ww), and milk (9.62 ng/g ww) were the highest of the food categories examined. Tris(2-butoxyethyl) phosphate (TBOEP) and triphenyl phosphate (TPHP) were the dominant OPEs. Cassava flour (Fufu) was the major contributor to the estimated daily intakes (EDIs) of Σ8OPEs, accounting for 26 and 33% of the EDI for children and adults respectively. For individual OPEs, TBOEP contributed the highest median EDI of 183 ng/kg bw/day (42% of the EDI for Σ8OPEs) for children and 159 ng/kg bw/day (39%) for adults, followed by TPHP (median – children: 92.3 ng/kg bw/day (21%); adults: 90.6 ng/kg bw/day (22%)). The range of OPE concentrations in the present study were comparable to data reported from other countries and EDIs for all OPEs were well below their corresponding health-based reference doses. This study identifies diet as a substantial human exposure pathway to OPEs in Africa.

B-189 Evaluate the suitability of urinary reference intervals for organophosphate flame retardants in healthy adult population from Southern Taiwan

Abstract Background Organophosphorus flame retardants (OPFRs) are chemical additives used to prevent fires and are widely used in furniture, electronics, plastics, and building materials. Its chemical structure is similar to human hormones, which are often misidentified and used in the human body, thereby interfering with the operation of normal physiological functions and causing endocrine system disorders, so it is also known as environmental hormones. Recently, it has been confirmed that exposure to OPFRs can cause health hazards such as neurotoxicity, endocrine disruption, hepatotoxicity, and reproductive dysfunction. In view of the increasing concern about the exposure of human OPFRs, but there is no laboratory in Taiwan to detect the content of human OPFRs. This study aims to develop a biomonitoring method for OPFRs, which is used to provide reliable information on the exposure status of individual OPFRs, and to establish a reference interval for OPFRs in the urine of different diseases and reference groups and confirm the potential of OPFRs as biomarkers in environmental medicine. Methods The Waters ACQUITY UPLC I-Class and Xevo TQ-XS IVD systems were developed to detect 10 OPFRs in urine: Tri-(n-butyl) phosphate (TNBP), Tris-(2-butoxyethyl) phosphate (TBEP), Tris-(1,3- dichloro-2-propyl) phosphate (TDCPP), Triphenyl phosphate (TPHP), Tris-(2-chloroethyl) phosphate (TCEP), Di-n-butylphosphate (DNBP), Bis-(butoxyethyl)-Phosphate (DBEP), Bis-(1,3-dichloro-2-propyl) phosphate (BDCPP), Diphenyl phosphate (DPHP), Bis (2-chloroethyl) phosphate (BCEP), and analytical methods. According to the CLSI C62A specifications, the methodology verification and confirmation passed the evaluation. A total of 538 patients (78 infertility, 167 hemodialysis, 96 esophageal cancer, 99 lung cancer and 98 endometrial cancer) and 175 reference groups were tested for urine samples. The ANOVA analysis was used to compare the differences in the content of 10 OPFRs compounds in the urine of subjects of different ethnic groups. ROC curve analysis was used to determine the best decision value of whether the disease was present, and Chi-square verification was used to conduct disease risk assessment and verify the feasibility of the set reference value. Results The BCEP (6.23 ± 2.19 ng/mL) of most patients with hemodialysis, lung cancer and esophageal cancer was significantly higher than the reference group (0.89 ± 0.38 ng/mL). Patients with gynecological diseases had a higher BDCPP (4.29 ± 1.97 ng/mL) than the reference population (0.76 ± 0.32 ng/mL), which was consistent with the conclusions of previous animal experiments. Since it is not easy to explain the direct correlation between OPFRs and the disease. We decided to sum the detection values of 10 OPFRs. We found that their sum was greater than 2.05 ng/mL. The risk of infertility was 37.8 (95% CI: 11.07–129.14), the risk value of esophageal cancer was 83.3 (95% CI: 25.25–274.85) and the risk value of severe chronic kidney disease was 56.7 (95% CI: 17.49–183.97). Conclusion Due to the different types of OPFRs used in different countries, it is impossible to directly apply the reference values of other countries to their own people. So we develop the OPFRs detect method and verify the reference values through a series of analysis and discussion. Which will help us further understand the association between these environmental hormones and diseases.

Insights into electrochemical oxidation of tris(2-butoxyethyl) phosphate (TBOEP) in aquatic media: Degradation performance, mechanisms and toxicity changes of intermediate products

Tris (2-butoxyethyl) phosphate (TBOEP) has gained significant attention due to its widespread presence and potential toxicity in the environment. In this study, the degradation of TBOEP in aquatic media was investigated using electrochemical oxidation technology. The anode Ti/SnO2–Sb/La–PbO2 demonstrated effective degradation performance, with a reaction constant (k) of 0.6927 min−1 and energy consumption of 1.24 kW h/m3 at 10 mA/cm2. CV tests, EPR tests, and quenching experiments confirmed that indirect degradation is the main degradation mechanism and ·OH radicals were the predominant reactive species, accounting for up to 93.8%. The presence of various factors, including Cl−, NO3−, HCO3− and humic acid (HA), inhibited the degradation of TBOEP, with the inhibitory effect dependent on the concentrations. A total of 13 intermediates were identified using UPLC-Orbitrap-MS/MS, and subsequent reactions led to their further degradation. Two main degradation pathways involving bond breaking, hydroxylation, and oxidation were proposed. Both Flow cytometry and the ECOSAR predictive model indicated that the intermediates exhibited lower toxic than the parent compound, resulting in a high detoxification rate of 95.9% for TBOEP. Although the impact of TBOEP on the phylum-level microbial community composition was found to be insignificant, substantial alterations in bacterial abundance were noted when examining the genus level. The dominant genus Methylotenera, representing 17.4% in the control group, decreased to 6.9% in the presence of TBOEP and slightly increased to 8.7% in the 4-min exposure group of degradation products. Electrochemical oxidation demonstrated its effectiveness for the degradation and detoxification of TBOEP in aqueous solutions, while it is essential to consider the potential impact of degradation products on sediment microbial communities.

Targeted and non-targeted screening of flame retardants in rural and urban honey

Flame retardants (FRs) are often added to commercial products to achieve flammability resistance, but they are not chemically bonded to the materials, so, they can be easily released into the environment during the production and disposal processes. When honeybees travel to collect nectar during the pollination process, they are prone to be contaminated by chemicals in the air. Therefore, honey contamination has been proposed as an indicator of the pollution status in a particular region. To date, the occurrence of flame retardants in urban honey has yet to be explored. In this study, a direct injection method was used, coupled with LC-QTOF-MS, to analyze honey samples. This method was applied to urban (n = 100) and rural (n = 100) honey samples from the Quebec province (Canada), and the levels of flame retardants in urban and rural honey samples were not significantly different. In the targeted approach, two of the target FRs, tris(2-butoxyethyl) phosphate (TBOEP) and triphenyl phosphate (TPHP), were detected and confirmed at an average trace concentration (<1 ng mL−1). Additionally, a non-targeted screening workflow with an in-house-built library was developed and validated to screen for flame retardants in honey. Tris (2-chloropropyl) phosphate (TCIPP) was identified in honey using the non-targeted screening workflow and confirmed using a pure analytical standard, but there are other compounds detected in the non-targeted analysis that have yet to be validated. This study was the first to report FR compounds based on a direct injection method, coupled with a non-targeted screening workflow, at a trace level in a honey matrix. It also showed that a non-targeted workflow was effective to detect and identify unknown compounds present in the honey sample; hence, this provided a novel angle for the occurrence of FRs in air, with honey as a bio-indicator.

Interactions of organophosphate flame retardants with human drug transporters

Organophosphate flame retardants (OPFRs) are environmental pollutants of increasing interest, widely distributed in the environment and exerting possible deleterious effects towards the human health. The present study investigates in vitro their possible interactions with human drug transporters, which are targets for environmental chemicals and actors of their toxicokinetics. Some OPFRs, i.e., tris(2-butoxyethyl) phosphate (TBOEP), tris(1,3-dichloroisopropyl) phosphate (TDCPP), tri-o-cresyl phosphate (TOCP) and triphenyl phosphate (TPHP), were found to inhibit activities of some transporters, such as organic anion transporter 3 (OAT3), organic anion transporting polypeptide (OATP) 1B1, OATP1B3, organic cation transporter 2 (OCT2) or breast cancer resistance protein (BCRP). These effects were concentration-dependent, with IC50 values ranging from 6.1 µM (for TDCPP-mediated inhibition of OCT2) to 51.4 µM (for TOCP-mediated inhibition of BCRP). OPFRs also blocked the transporter-dependent membrane passage of endogenous substrates, notably that of hormones. OAT3 however failed to transport TBOEP and TPHP. OPFRs additionally repressed mRNA expressions of some transporters in cultured human hepatic HepaRG cells, especially those of OAT2 and OCT1 in response to TOCP, with IC50 values of 2.3 µM and 2.5 µM, respectively. These data therefore add OPFRs to the expanding list of pollutants interacting with drug transporters, even if OPFR concentrations required to impact transporters, in the 2–50 µM range, are rather higher than those observed in humans environmentally or dietarily exposed to these chemicals.

Application of molecular dynamic simulation on evaluating toxicity mechanisms of organophosphate esters to Photobacterium phosphoreum

Organophosphate esters (OPEs) that are widely used as additives in industrial products have been monitored ubiquitously in environmental media. With the health hazards and ecological risks caused by OPEs being attracted more and more attention, screening toxicity mechanism was essential for risk assessment. In this study, Photobacterium phophorium was employed to test the acute toxicity of OPEs. Integrating toxicity test and molecular dynamics (MD) simulation, we calculated the binding affinity between OPEs and n-octanol (C8H18O)/ phospholipid bilayer (DPPC) to further explore the mechanism of toxicity. Good correlationship between the median effective concentration (EC50) of OPEs and binding affinity was found. Binding affinity of selected OPEs with the C8H18O/DPPC presented similar tendency. The mode of action (MOA) for OPEs to Photobacterium phophorium was shown that tris (1, 3-dichloro-2-propyl) phosphate (TDCP) belonged to reactive mechanism, triphenyl phosphate (TPhP) and tris (2-butoxyethyl) phosphate (TBEP) belonged to narcosis mechanism. It was proposed a creative method to quickly evaluate toxicity mechanisms of organophosphate esters by integrating the toxicity test and MD simulation, which could be an alternative methodology to obtain toxicity mechanism without using model organisms.

Organohalogenated flame retardants and organophosphate esters from home and preschool dust in Sweden: Pollution characteristics, indoor sources and intake assessment

This study analysed settled dust samples in Sweden to assess children's combined exposure to 39 organohalogenated flame retardants (HFRs) and 11 organophosphate esters (OPEs) from homes and preschools. >94 % of the targeted compounds were present in dust, indicating widespread use of HFRs and OPEs in Swedish homes and preschools. Dust ingestion was the primary exposure pathway for most analytes, except BDE-209 and DBDPE, where dermal contact was predominant. Children's estimated intakes of ∑emerging HFRs and ∑legacy HFRs from homes were 1–4 times higher than from preschools, highlighting higher exposure risk for HFRs in homes compared to preschools. In a worst-case scenario, intakes of tris(2-butoxyethyl) phosphate (TBOEP) were 6 and 94 times lower than the reference dose for children in Sweden, indicating a potential concern if exposure from other routes like inhalation and diet is as high. The study also found significant positive correlations between dust concentrations of some PBDEs and emerging HFRs and the total number of foam mattresses and beds/m2, the number of foam-containing sofas/m2, and the number of TVs/m2 in the microenvironment, indicating these products as the main source of those compounds. Additionally, younger preschool building ages were found to be linked to higher ΣOPE concentrations in preschool dust, suggesting higher ΣOPE exposure. The comparison with earlier Swedish studies indicates decreasing dust concentrations for some banned and restricted legacy HFRs and OPEs but increasing trends for several emerging HFRs and several unrestricted OPEs. Therefore, the study concludes that emerging HFRs and OPEs are replacing legacy HFRs in products and building materials in homes and preschools, possibly leading to increased exposure of children.

Concentrations, spatial and seasonal variations of Organophosphate esters in UK freshwater Sediment

This study provides the first report of organophosphate esters (OPEs) in UK freshwater sediments with a focus on the possible impact of factors such as spatial/seasonal variation and wastewater treatment plants (WWTPs) on the measured OPE concentrations in surficial sediment from 3 UK rivers and 1 canal. Detection frequencies of: (tris (chloroethyl) phosphate (TCEP), tris (2-chloroisopropyl) phosphate (TClPP), tris (1,3-dichloro-2 propyl) phosphate (TDClPP), tri-n-butyl phosphate (TNBP), tris (2-butoxyethyl) phosphate (TBOEP), 2-ethylhexyl diphenyl phosphate (EHDPP), tris (phenyl) phosphate (TPHP), and tri-m-tolyl phosphate (TmTP)) ranged from 58% to 100%. The concentration of Σ8OPEs ranged from 107 ng g−1 (dry weight - dw) (in the Worcester-Birmingham canal) to 52 ng g−1 (dw) in both Rivers Severn and Sowe). The highest ∑8OPE concentration for all study locations was recorded during the autumn months (September, October, and November), and concentrations of ∑8OPEs in sediment samples from the River Severn, River Tame, and River Sowe all varied inversely with the river level and flow rate. The average concentrations of each target OPE in each study location were lower than those reported elsewhere but fell broadly within the range of concentrations reported from other countries. The potential risk posed by target OPEs in all study locations was found to be low, except for a moderate risk identified for EHDPP in the Worcester - Birmingham canal.