Butyl Benzyl Phthalate Research Articles

Biochemical and Multi-Omics Approaches To Obtain Molecular Insights into the Catabolism of the Plasticizer Benzyl Butyl Phthalate in Rhodococcus sp. Strain PAE-6.

Phthalate diesters are extensively used as plasticizers in manufacturing plastic materials; however, because of their estrogenic properties, these chemicals have emerged as a global threat to human health. The present study investigated the course of degradation of a widely used plasticizer, benzyl butyl phthalate (BBP), by the bacterium PAE-6, belonging to the genus Rhodococcus. The metabolism of BBP, possessing structurally dissimilar side chains, was evaluated biochemically using a combination of respirometric, chromatographic, enzymatic, and mass-spectrometric analyses, depicting pathways of degradation. Consequently, the biochemical observations were corroborated by identifying possible catabolic genes from whole-genome analysis, and the involvement of inducible specific esterases and other degradative enzymes was validated by transcriptomic, reverse transcription-quantitative PCR (RT-qPCR) and proteomic analyses. Nonetheless, phthalic acid (PA), an intermediate of BBP, could not be efficiently metabolized by strain PAE-6, although the genome contains a PA-degrading gene cluster. This deficiency of complete degradation of BBP by strain PAE-6 was effectively managed by using a coculture of strains PAE-6 and PAE-2. The latter was identified as a Paenarthrobacter strain which can efficiently utilize PA. Based on sequence analysis of the PA-degrading gene cluster in strain PAE-6, it appeared that the alpha subunit of the multicomponent phthalate 3,4-dioxygenase harbors a number of altered residues in the multiple sequence alignment of homologous subunits, which may play a role(s) in poor turnover of PA. IMPORTANCE Benzyl butyl phthalate (BBP), an estrogenic, high-molecular-weight phthalic acid diester, is an extensively used plasticizer throughout the world. Due to its structural rigidity and hydrophobic nature, BBP gets adsorbed on sediments and largely escapes the biotic and abiotic degradative processes of the ecosystem. In the present study, a potent BBP-degrading bacterial strain belonging to the genus Rhodococcus was isolated that can also assimilate a number of other phthalate diesters of environmental concern. Various biochemical and multi-omics analyses revealed that the strain harbors all the required catabolic machinery for the degradation of the plasticizer and elucidated the inducible regulation of the associated catabolic genes and gene clusters.

#3383 ASSOCIATION BETWEEN MELAMINE AND PHTHALATES AND URINARY RENAL INJURY MARKERS AMONG CHILDREN AGED 4 YEARS

Abstract Background and Aims Chronic kidney disease (CKD) is a global public health issue and the prevalence and incidence of CKD and end-stage renal disease (ESRD) in Taiwan are among the highest in the world. The pathophysiology of renal function downhill is complex and multifactorial, and previous studies suggest that we should be concerned about the effects of low-dose environmental exposure to melamine and phthalate in increasing the risk of renal injury in susceptible populations such as children. However, the sex difference in renal injury related to environmental exposure among children is unknown. The aim of this study is to investigate the relationship between early renal injury biomarkers and melamine and phthalate exposure among boys and girls aged 4 years in Taiwan. Method In total, 1,676 pregnant women were enrolled in the original Taiwan Maternal and Infant Cohort Study (TMICS), a multicenter birth cohort study conducted at 9 hospitals in northern, central, southern, and eastern Taiwan from October 2012 to May 2015. Of those, 694 children aged 4 years participated in follow-up questionnaire interviews, received physical examinations and blood and urine tests from August 2016 to February 2020. After excluding 142 participants with missing data, the final statistical analysis of follow-up data included 552 children. One-spot overnight urine specimens were used to simultaneously measure melamine, 11 phthalate metabolites, and two markers of renal injury, microalbumin and N-acetyl-beta-D-glucosaminidas (NAG). Average daily intake (ADI) levels of melamine and six parental phthalates, including DEHP (di-2-ethylhexylphthalate), DiBP (Dibutyl phthalate), DnBP (Di-n-butyl phthalate), BBzP (Butyl benzyl phthalate), and DEP (Diethyl phthalate), were estimated using a creatinine excretion-based model from urine melamine and phthalate metabolites. We used a weighted quantile sum (WQS) regression model to select the most important exposure variables of ADI levels of phthalates and melamine associated with urine microalbumin to creatinine ratio (ACR) and NAG; Furthermore, to examine effects of those most important exposure variables on ACR and NAG in multivariable linear regression models. The significance was set as two-sided p < 0.05. Results Of them, 319 (57.8%) and 223(42.2%) were boys and girls, respectively, with a median age of 4.0±0.8 years old. Median ADI levels (µg/kg bw/day) were 5.73 for DEHP, 1.75 for DEP, 3.23 for DnBP, 0.07 for BBzP, 1.37 for DiBP, and 1.18 for melamine and there is not significantly different between boys and girls. Using the WQS regression model to examine the association between ADI levels of melamine and phthalates and urine ACR and NAG, we found that a significant and positive association between the WQS score and ACR (β1 = 0.083, p = 0.023). ADI levels of melamine had the highest weight (0.650). Furthermore, we found that the highest (quartile 4) of ADI levels of melamine had the significantly higher ACR in all children (adjusted β = 0.131, p = 0.036), compared to other quartiles (quartile 1, 2 and 3). In subgroup analysis, the significant association between melamine intake and urine ACR was found in boys (adjusted β = 0.249, p = 0.003), not in girls. Conclusion Environmental exposure to melamine may be associated with urine ACR among children aged 4 years in Taiwan, and boys may be easily affected by melamine exposure.

Thermal Hydrolysis Pretreatment Effects on Endocrine Disrupting Compounds and Microbial Communities in Wastewater Sludge from Anaerobic Digestion

Concerns regarding endocrine disrupting compounds (EDCs) in wastewater treatment plant effluents have led to the need to better understand their fate during various treatment processes. The thermal hydrolysis process (THP) is a growing technology; this article aims to better understand the impacts of THP on EDCs. Serum bottles were used to understand how the THP of anaerobically digested wastewater influences concentrations of phthalic acid esters (PAEs) and antimicrobials. The succession of DNA-based microbial community was followed to assess conditions of contaminant biotransformation. Sludge samples were collected at different locations, placed in 250 mL serum bottles, and inoculated with samples collected from the anaerobic digestion solid recycle line to compare the influence of the THP pretreatment. Bottles were covered, kept at 37°C, and agitated for 22 days, with periodic destructive sampling for the chemical analysis of antimicrobials, PAEs, and transformation products, as well as the microbial community structure. Results demonstrated an increase in the concentrations of triclosan (TCS), triclocarban (TCC), and their transformation products with and without THP pretreatment. 2,4-Dichlorophenol increased at a significantly higher rate in pretreated sludge, while the TCC concentrations increased significantly faster in untreated sludge. Pretreatment did not significantly influence the formation rates of TCS and methyl triclosan. Pretreatment impacts on phthalate concentrations varied. Di(2-ethylhexyl) phthalate decreased and diisononyl phthalate concentrations were unchanged. Benzyl butyl phthalate increased in sludge that had undergone pretreatment and decreased in sludge without. PAE metabolites generally increased during the course of the experiments. Results demonstrate the potential for complex transformation processes and indicate the ability of THP to influence concentrations of certain compounds of concern. Analysis of the microbial community structure did not demonstrate any statistically significant difference between sludge with pretreatment and sludge without over the course of the experiment. These results indicate that changes in chemical concentrations could be due to other physicochemical mechanisms not examined.

Appraisal of the Temporospatial Migration and Potential Ecotoxicity of Phthalic Acid Esters in Municipal Effluents, Rivers and Dam—A Catchment-Wide Assessment

Herein, the catchment-wide temporal dynamics and potential ecotoxicological risk of phthalic acid esters (PAEs) in aquatic ecosystems were assessed. Specifically, water samples were collected for a period of six consecutive months from seven selected sites, i.e., covering both dry and wet seasons for seasonal variabilities. The appraised PAEs comprised dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), benzylbutyl phthalate (BBP), diphenyl phthalate (DPP), di-n-hexyl phthalate (DHP), bis(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate (DOP), diisodecyl phthalate (DiDP) and diisononyl phthalate (DiNP)) in municipal wastewater effluents, rivers and dam. Their concentrations were quantified using a gas chromatography–flame ionisation detector (GC–FID) via the liquid–liquid extraction mode. The appraised PAEs were ubiquitous in the selected sampling points, with DBP being the most abundant PAE homologue throughout the assessed localities. In particular, quantifiable concentrations were 18.9, 37.9 and 11.5 μg/L for DBP in wastewater effluents, rivers and the dam catchment, respectively, and for overall Σ10PAEs of minimum, mean and maximum of 0.492, 3.6 ± 9.82 and 63.2 μg/L, respectively. In addition, PAE concentrations in the effluents, rivers, and dam samples showed no significant differences with p < 0.05. The overall prominent sequence for ∑PAEs registered: 53.3 > 10.1 > 10.0 > 9.8 > 4.3 > 2.5 > 1.8 > 1.7 > 1.1 > 0.9% for DBP > DEHP > DiDP > DOP > DHP > DPP > BBP > DMP > DEP > DiNP, respectively. The ecotoxicological risk assessment (risk quotient method) showed that DBP and DiDP posed high risk (RQ ≥ 1), and DOP, DEHP, DHP, DiNP and BBP posed median risk to aquatic organisms (0.1 ≤ RQ < 1), while the risk from DMP and DEP was minimal (RQ < 0.1). Additionally, DBP, DEHP, DOP, DPP and DiDP were higher than the water criterion (3 μg/L) of PAEs recommended by the United States Environmental Protection Agency (USEPA) for the protection of aquatic life. Findings from this study should go a long way in guiding regulators, custodians and catchment management forums, along with interested and affected parties, regarding the status and potential ecotoxicological effects of PAEs in the receiving environment.

A survey of phthalates in flavored olive oils from Turkey

Phthalates are organic contaminants that are used as plasticizers in many plastic food packaging materials. Because of their lipophilic character, oils are the primary source of human exposure to phthalates. In this study, the presence of five phthalate esters; diethylhexyl phthalate (DEHP), dibutyl phthalate (DBP), butyl benzyl phthalate (BBP), diisononyl phthalate (DINP) and diisodecyl phthalate (DIDP) in olive oils flavored with different materials and marketed in Turkey in 2020 was determined. The samples included BBP, DINP, DIDP at lower concentrations than their LOQ. DEHP was the most abundant phthalate in all samples at varying concentrations between < LOQ to 1.81 mg/kg. The highest amount of DEHP was found in the oil sample flavored with bergamot (1.81 mg/kg). DBP was detected in 9 of the 25 samples at concentrations from 0.11 to 0.27 mg/kg.

Contaminant Risk and Social Vulnerability Associated with Crustacean Shellfish Harvest in the Highly Urbanized San Diego Bay, USA

People in coastal cities around the world harvest seafood from local bays despite well-documented health risks. In cities such as San Diego, California, USA, much information about contaminants and human consumption patterns exists for finfish but is largely lacking for shellfish. This study sought to better understand shellfish contamination risks and human vulnerability to inform management and advisories. In summer 2018 and winter 2019, we sampled crustaceans for chemical contaminants and anthropogenic debris and throughout the year surveyed people harvesting from three public fishing piers around San Diego Bay. Of the emerging contaminants found, pyrethroids, benzylbutyl phthalate, PFOS and anthropogenic debris were in differing concentrations in the muscle and viscera of the California spiny lobster and two species of crabs. Combined with previous metal and organic contaminant data from the lobster, 22 contaminants were detected with 5 exceeding consumption thresholds and 8 lacking defined thresholds. California spiny lobster was the main crustacean harvested from piers, attracting shellfishers from a range of ages, incomes, home locations and self-identified racial/ethnic groups. Consumption preferences (e.g., muscle or viscera) were non-discriminant, making lobster contamination a community-wide risk. More monitoring of emerging contaminants and different shellfish species (and tissues) of interest is recommended to capture the spatial and temporal dynamics of health risks, especially because the use of bivalves as sentinels may not reveal the same risks (e.g., PFAS, phosphate flame retardants).

Determination of phthalate in PVC food wrap by gas chromatography mass spectrometry

Toxic phthalates that can be released from food packaging into food are currently a matter of concern, affecting consumers’ health. However, in Vietnam, no studies have been published on this group of substances in food packaging and films. In this research, a method for the simultaneous determination of 7 typical phthalates, including benzyl butyl phthalate (BBP), dibutyl phthalate (DBP), di(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate (DNOP), diisodecyl phthalate (DIDP), diisononyl phthalate (DINP), di-(2-ethylhexyl) adipate (DEHA) in food wrap samples by gas chromatography mass spectrometry (GC-MS) using internal standards has been developed and validated. The limit of detection and limit of quantification for all substances was 0.03 mg/kg and 0.10 mg/kg, respectively. The recoveries of the method were in the range of 82-105%. Relative standard deviation (RSD) ranged from 5.6 to 7.5%. The method has been applied effectively to analyze the content of phthalates in 35 food wrap samples that were collected from markets in Hanoi. Analytical results showed that ten samples were detected with phthalates, of which three samples contained DEHA exceeding the specific migration limit (SML). This study contributes to consumer health protection and advises the regulatory agency on the addition of safety regulations for PVC food wrap in particular and other food packaging materials in general.

Direct Analysis of Bio-Molecules in Solid Materials Using Electrospray Ionisation Mass Spectrometry Coupled with Laser Ablation and a Liquid Sampling Technique.

In situ and rapid analysis of organic compounds using a combination of a newly-developed laser ablation in liquid (LAL) sampling technique combined with electrospray ionisation mass spectrometry (ESI-MS) is reported. The LAL is a technique that allows laser ablation to be conducted in a liquid medium containing organic compounds that were effectively extracted from solid materials into the liquid medium. Three organic compounds (valine, caffeine, and benzyl butyl phthalate (BBP)) were subjected to analysis. The LAL sampling was conducted in the fast-laser scanning mode using Galvanometric optics, and the total ablation time required for the sampling from a 1 mm2 area was about 3 s, thus providing rapid sampling. The resulting sample solution was directly introduced into the ESI-MS system, without the need for any chromatographic separation. To evaluate the analytical capability of the LAL technique coupled with ESI-MS, both the overall transmission efficiencies of analytes from solid materials to the ion detector, and the repeatabilities of the measurements were rigorously tested. This involved the use of synthetic, in-house prepared standard materials containing the analytes. The overall ion yields were about 1.1×10-3% for valine, 8.7×10-3% for caffeine, and 6.7×10-4% for BBP. By comparing the ion yields obtained by the injection of an analyte solution and a standard solution through the mass spectrometer, the recoveries through the LAL sampling were approximately 31% for valine, 45% for caffeine, and 37% for BBP. In addition, the analytical repeatabilities for all analytes were better than 6%. The analytical repeatabilities were mainly affected by either the heterogeneity of the in-house standard materials or changes in the plasma temperature by coexisting, laser-induced sample particles. It should be noted that not only water-soluble compounds (caffeine and valine), but also non-soluble compound (BBP) could be measured by the LAL-ESI-MS, which is one of the great advantages over the conventional liquid extraction surface analysis technique. The data obtained here clearly demonstrate that the LAL-ESI-MS has the potential for being a fast and user-friendly analytical technique for the in-situ detection for both the water-soluble and water-insoluble molecules.

Ecological risk assessment of phthalates in the urban channels of São Vicente, Brazil

Phthalate acid esters (PAEs) are a group of plasticising chemical compounds used in the plastic industry worldwide that are well known for their environmental contamination and toxicological effects as endocrine disruptors. In this work, the occurrence and preliminary ecological risk of six PAEs – namely, dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-octyl phthalate, butyl benzyl phthalate, di-n-butyl phthalate (DBP) and di(2-ethylhexyl) phthalate – were investigated, for the first time, in five urban drainage channels located along the poor nearby neighbourhoods on the outskirts of São Vicente City, São Paulo, Brazil, whose diffuse loads flow continuously to the estuarine waters of this island. Of these, three congeners, DMP (<limit of detection (LOD), 0.023 μg/l), DEP (<LOD, 0.033 μg/l) and DBP (<LOD, 0.042 μg/l), were consistently quantified using gas chromatography coupled with tandem mass spectrometry. Specifically, the DBP occurrence is a cause of environmental concern for the São Vicente estuary, because the results suggest moderate risk for algae and fishes and high ecological risk for crustaceans after acute exposure. Therefore, even at low concentrations, the occurrence of PAEs cannot be neglected in this coastal zone. In addition, the present study reinforces the need for further ecotoxicological studies (particularly with tropical marine organisms) to assess the toxicity of these bioactive compounds.

Occurrence, distribution and risk assessment of phthalate esters in 51 urban wastewater treatment plants in Shaanxi Province, China

Wastewater treatment plants (WWTPs) are both a major collection point for phthalate esters (PAEs) and an important point source for their entry into the natural water environment. In this study, we conducted a large-scale investigation on the occurrence, distribution and ecological risk of PAEs in 51 WWTPs in Shaanxi Province, which is located in the north-south transition zone of China. Benzylbutyl phthalate and diisobutyl phthalate were the major compounds in the influent and effluent, respectively, with average concentrations of 32.97 and 18.07 μg/L. However, there was no significant spatial difference in the concentration of PAEs in WWTPs wastewater in different regions of Shaanxi Province. The removal effect of PAEs from wastewater varied with different treatment processes for WWTPs. The anaerobic-anoxic-oxic (A2O) process showed the highest removal efficiency of ∑PAEs, which could reach 89.34 %. A risk quotient (RQ) was used to calculate the ecological risk posed by the PAEs detected in the effluent. Diisobutyl phthalate, dibutyl phthalate, butyl benzyl phthalate, and di(2-ethylhexyl) phthalate pose medium to high ecological risk to receiving waters (RQ = 0.51–3.70). It was estimated that the annual mass load of PAEs discharged to receiving water bodies through WWTPs wastewater in all Shaanxi Province was 32.34 tons.

Regulation of the cell cycle and P13K/AKT/mTOR signaling pathway by phthalates in normal human breast cells

ObjectiveTo investigate the impact of phthalates, including Butyl benzyl phthalate (BBP), di(n-butyl) phthalate (DBP), and di(2-ethylhexyl) phthalate (DEHP), in breast carcinogenesis. Materials and methodsMCF-10A normal breast cells were treated with phthalates (100 nM) and 17β-estradiol (E2, 10 nM), which were co-cultured with fibroblasts from normal mammary tissue adjacent to estrogen receptor positive primary breast cancers. Cell viability was determined using a 3-(4,5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Cell cycles were analyzed using flow cytometry. The proteins involving cell cycles and P13K/AKT/mTOR signaling pathway were then evaluated by Western blot analysis. ResultsMCF-10A co-cultured cells treated with E2, BBP, DBP, and DEHP exhibited a significant increase in cell viability using MTT assay. The expressions of P13K, p-AKT, and p-mTOR, as well as PDK1 expression, were significantly higher in MCF-10A cells treated with E2 and phthalates. E2, BBP, DBP, and DEHP significantly increased cell percentages in the S and G2/M phases. The significantly higher expression of cyclin D/CDK4, cyclin E/CDK2, cyclin A/CDK2, cyclin A/CDK1, and cyclin B/CDK1 in MCF-10A co-cultured cells were induced by E2 and these three phthalates. ConclusionThese results provide consistent data regarding the potential role of phthalates exposure in the stimulating proliferation of normal breast cells, enhancing cell viability, and driving P13K/AKT/mTOR signaling pathway and cell cycle progression. These findings strongly support the hypothesis that phthalates may play a crucial role in breast tumorigenesis.

Deep Eutectic Solvent-based green extraction and gas chromatography determination of phthalates released from food contact materials

A sensitive and efficient green emulsification liquid-liquid microextraction (ELLME) method using deep eutectic solvents (DES) for extraction of phthalates released from food contact materials (FCMs) was optimized for GC-MS determination of Butyl Benzyl Phthalate (BBP) and Di-2-Ethylhexyl Phthalate (DEHP). The optimal DES system for phthalate extraction was determined to be Choline Chloride:Phenol (1:2 molar ratio). Tetrahydrofuran (THF) was utilized as the emulsifier solvent. The effects of vortex agitation times and centrifugation times on extraction efficiency were investigated. The method yielded quantification limits (LOQ) of 0.036 and 0.005 mgL-1 for BBP and DEHP, respectively. Repeatability relative standard deviations (RSDr) of 2.9% and 2.2% were obtained for BBP and DEHP, respectively, while corresponding medium precision relative standard deviations (RSDR) were 2.8% and 3.2%. Recovery rates from spiked samples were 94.8% for BBP and 95.1% for DEHP. Finally, determination of BBP and DEHP released from contact materials into water and beverage samples at various temperatures confirmed the applicability of the method for assessment of phthalates and their migration from FCMs.

Exposure to phthalates and DiNCH among preschool children in Sweden: Urinary metabolite concentrations and predictors of exposure

Several plasticizing chemicals induce endocrine disrupting effects in humans, and the indoor environment is suggested to be a source of exposure. As children are particularly vulnerable to the effects from exposure to endocrine disrupting chemicals (EDCs), it is essential to monitor exposure to EDCs such as phthalates and non-phthalate plasticizers in indoor environments intended for use by children. The aim of this study was to assess everyday plasticizer exposure among preschool-aged children in Sweden by measuring urinary plasticizer metabolite concentrations. In addition, it was investigated whether the concentrations would be altered as a result of the children spending part of the day at preschool, in comparison with weekend exposure, when they may spend more time in home environments or engage in various weekend and leisure activities. For this purpose, fourteen metabolites from eight phthalates (di-ethylhexyl phthalate, DEHP; di-n-butyl phthalate, DnBP; di-isobutyl phthalate, DiBP; butyl-benzyl phthalate, BBzP; di-iso-nonyl phthalate, DiNP; di-propylheptyl phthalate, DPHP; di-iso-decyl phthalate, DiDP; and di-ethyl phthalate, DEP) and one non-phthalate plasticizer (di-isononyl cyclohexane 1,2-dicarboxylate, DiNCH) were measured in 206 urine samples collected at four occasions, i.e. twice during the winter and twice during the spring from 54 children (mean5.1 years, SD 0.94) enrolled at eight preschools in Sweden. A detection frequency (DF) of 99.9% for the 14 metabolites indicates a widespread exposure to plasticizers among children in Sweden. Compared to previous Swedish and international studies performed during approximately the same time period, high urinary concentrations of monobenzyl phthalate (MBzP), a metabolite from the strictly regulated BBzP, were measured in this study (median 17ng/mL). Overall, high urinary phthalate metabolite concentrations were observed in this study compared to the US CDC-NHANES from the same time period and similar age-group. Compared to European studies, however, similar concentrations were observed for most metabolites and the urinary concentrations from few participating children exceeded the human biomonitoring guidance values (HBM-GV) for children. After days with preschool attendance, lower urinary concentrations of metabolites originating from DEP and phthalates that are strictly regulated within the EU REACH legislation (DEHP, DnBP, and DiBP) and higher concentrations of metabolites originating from DiNP, DPHP, and DiDP, i.e. less or non-regulated phthalates were found compared the urinary concentrations of these metabolites in weekends. This may indicate that factors in the indoor environment itself are important for the extent of the plasticizer exposure. All the analyzed metabolites were measured in lower concentrations in urine collected from children attending preschools built or renovated after the year 2000, while no seasonal differences were observed in this study.

Urinary concentration of phthalates and bisphenol A during minipuberty is associated with reproductive hormone concentrations in infant boys.

The transient postnatal activation of the hypothalamic-pituitary-gonadal hormone axis is termed minipuberty and considered an important developmental period, which is highly sensitive to endocrine disruption. Here, we explore exposure-outcome associations during minipuberty between concentrations of potentially endocrine disrupting chemicals (EDCs) in urine of infant boys and their serum reproductive hormone concentrations. In total, 36 boys participating in the COPENHAGEN Minipuberty Study had data available for both urine biomarkers of target endocrine disrupting chemicals and reproductive hormones in serum from samples collected on the same day. Serum concentrations of reproductive hormones were measured by immunoassays or by LC-MS/MS. Urinary concentrations of metabolites of 39 non-persisting chemicals, including phthalates and phenolic compounds, were measured by LC-MS/MS. Nineteen chemicals had concentrations above the limit of detection in ≥50% of children and were included in data analysis. Associations of urinary phthalate metabolite and phenol concentrations (in tertiles) with hormone outcomes (age- and sex-specific SD-scores) were analysed by linear regression. Primarily, we focused on the EU regulated phthalates; butylbenzyl phthalate (BBzP), di-iso-butyl phthalate (DiBP), di-n-butyl phthalate (DnBP), and di-(2-ethylhexyl) phthalate (DEHP) as well as bisphenol A (BPA). Urinary metabolites of DiBP, DnBP and DEHP were summed and expressed as ∑DiBPm, ∑DnBPm and ∑DEHPm. Compared to boys in the lowest ∑DnBPm tertile, urinary concentration of ∑DnBPm was associated with concurrent higher luteinizing hormone (LH) and anti-Müllerian hormone (AMH) SD-scores as well as lower testosterone/LH ratio in boys in the middle ∑DnBPm tertile (estimates (CI 95%) 0.79 (0.04; 1.54), 0.91 (0.13; 1.68), and -0.88 (-1.58;-0.19), respectively). Further, higher insulin-like peptide 3 (INSL3) SD-scores and lower DHEAS SD-score in boys in the highest ∑DnBPm tertile (0.91 (0.12; 1.70) and -0.85 (-1.51;-0.18), respectively) were observed. In addition, boys in the middle and highest ∑DEHPm tertile had higher LH (1.07 (0.35; 1.79) and 0.71 (-0.01; 1.43), respectively) and in the highest ∑DEHPm tertile also higher AMH (0.85 (0.10; 1.61)) concentration SD-scores, respectively. Boys in the highest BPA tertile had significantly higher AMH and lower DHEAS concentration compared to boys in the lowest BPA tertile (1.28 (0.54; 2.02) and -0.73 (-1.45; -0.01)), respectively. Our findings indicate that exposure to chemicals with known or suspected endocrine disrupting potential, especially the EU-regulated DnBP, DEHP and BPA, may modify male reproductive hormone concentrations in infant boys suggesting that minipuberty is a critical window sensitive to endocrine disruption.

Exposure of preterm neonates receiving total parenteral nutrition to phthalates and its impact on neurodevelopment at the age of 2 months

This prospective study assessed the exposure to phthalates of preterm neonates who received total parenteral nutrition (TPN) during their stay in the neonatal intensive care unit (NICU) and the risk of neurodevelopment delays at the age of 2 months. Our study recruited 33 preterm neonates who required TPN upon NICU admission. Urine samples for analyzing phthalate metabolites were obtained at admission and then daily until the last day of receiving TPN. Phthalates in the daily TPN received by the preterm neonates were analyzed. The neurodevelopment of the neonates was assessed using the Ages and Stages Questionnaire Edition 3 (ASQ-3). Diethyl phthalate and butyl benzyl phthalate were found in all TPN samples, while 27% and 83% contained dibutyl phthalate and di-(2-ethylhexyl) phthalate (DEHP), respectively. Yet, the daily dose of each phthalate that our preterm neonates received from TPN was much lower than the recommended tolerable limit. Urinary levels of monobenzyl phthalate and four metabolites of DEHP [i.e., mono-(2-ethylhexyl) phthalate (MEHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate, mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), and mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP)] and the sum of four DEHP metabolites (∑4DEHP) increased significantly in preterm neonates before discharge. However, these levels were not correlated with their phthalate parent compounds in TPN, suggesting other sources of exposure in the NICU. At 2 months, we found that urinary levels of mono-iso-butyl phthalate (MiBP), MECPP, MEHP, and ∑4DEHP were inversely related to fine motor skills. After adjusting for head circumference, the inverse relationships remained significant, suggesting direct effects from phthalates. Given the extreme vulnerability of our population, it is critical to minimize exposure to phthalates during their NICU stay.

Silibinin supplementation ameliorates the toxic effects of butyl benzyl phthalate on porcine oocytes by eliminating oxidative stress and autophagy

Butyl benzyl phthalate (BBP) is a common environmental pollutant, it is high in paints, adhesives and other decorative materials, food packaging bags, cleaning agents, is a plasticizer is very widely used in daily life. However, it remains unknown whether BBP causes damage to oocytes cultured in vitro and whether there is an effective rescue strategy. Here, we evaluated the effects of exposure to different concentrations of BBP (10, 50, and 100 μM) on the meiosis of porcine oocytes. The results showed that exposure to BBP (100 μM) severely impaired expansion of cumulus-oocyte complex (COCs) and PBE (control:71.6% vs 100 μM: 48.8%). Spindle conformation and chromosome alignment were also significantly abnormal (34.8% and 46.0%, respectively) compared to the control (11.1% and 17.5%, respectively), and BBP caused damage to microfilaments and cortical granules (CGs). In addition, oocyte exposure to BBP induced impaired mitochondrial function and disrupted mitochondrial integrity. Silibinin is a natural active substance isolated from the seeds of Silybum marianum (L.) Gaertneri with strong antioxidant and anti-inflammatory effects. Noteworthy, we added different concentrations of silibinin (10, 20, and 50 μM) to BBP-exposed oocytes for rescue experiments, where 50 μM effectively rescued BBP-induced meiotic failure (70.6%). It also prevented the generation of excessive autophagy and apoptosis in oocytes by inhibiting the production of ROS. In a word, our results suggest that supplementation of silibinin attenuates the impaired oocyte development caused by BBP exposure，which provides a potential strategy to protect oocytes from environmental pollutants.

Evaluation of Surface Properties and Separation Performance of NF and RO Membranes for Phthalates Removal

Many studies indicated that phthalates, a common plasticizer, lurk silently in water bodies and can potentially harm living organisms. Therefore, removing phthalates from water sources prior to consumption is crucial. This study aims to evaluate the performance of several commercial nanofiltrations (NF) (i.e., NF3 and Duracid) and reverse osmosis (RO) membranes (i.e., SW30XLE and BW30) in removing phthalates from simulated solutions and further correlate the intrinsic properties of membranes (e.g., surface chemistry, morphology, and hydrophilicity) with the phthalates removal. Two types of phthalates, i.e., dibutyl phthalate (DBP) and butyl benzyl phthalate (BBP), were used in this work, and the effects of pH (ranging from 3 to 10) on the membrane performance were studied. The experimental findings showed that the NF3 membrane could yield the best DBP (92.5-98.8%) and BBP rejection (88.7-91.7%) regardless of pH, and these excellent results are in good agreement with the surface properties of the membrane, i.e., low water contact angle (hydrophilicity) and appropriate pore size. Moreover, the NF3 membrane with a lower polyamide cross-linking degree also exhibited significantly higher water flux compared to the RO membranes. Further investigation indicated that the surface of the NF3 membrane was severely covered by foulants after 4-h filtration of DBP solution compared to the BBP solution. This could be attributed to the high concentration of DBP presented in the feed solution owing to its high-water solubility (13 ppm) compared to BBP (2.69 ppm). Further research is still needed to study the effect of other compounds (e.g., dissolved ions and organic/inorganic matters that might be present in water) on the performance of membranes in removing phthalates.

Measurement of Phthalates in Settled Dust in University Dormitories and Its Implications for Exposure Assessment

Six phthalates: dimethyl phthalate (DMP), diethyl phthalate (DEP), di(n-butyl) phthalate (DnBP), butyl benzyl phthalate (BBzP), di(2-ethylhexyl) phthalate (DEHP), and di(n-octyl) phthalate (DOP) in settled dust on different indoor surfaces were measured in 30 university dormitories. A Monte Carlo simulation was used to estimate college students’ exposure via inhalation, non-dietary ingestion, and dermal absorption based on measured concentrations. The detection frequencies for targeted phthalates were more than 80% except for DEP (roughly 70%). DEHP was the most prevalent compound in the dust samples, followed by DnBP, DOP, and BBzP. Statistical analysis suggested that phthalate levels were higher in bedside dust than that collected from table surfaces, indicating a nonuniform distribution of dust-phase phthalates in the sleep environment. The simulation showed that the median DMP daily intake was 0.81 μg/kg/day, which was the greatest of the targeted phthalates. For the total exposures to all phthalates, the mean contribution of exposures during the daytime and sleeping time was 54% and 46%, respectively.

Long-term exposure to di(2-ethylhexyl) phthalate, diisononyl phthalate, and a mixture of phthalates alters estrous cyclicity and/or impairs gestational index and birth rate in mice.

Phthalates are found in plastic food containers, medical plastics, and personal care products. However, the effects of long-term phthalate exposure on female reproduction are unknown. Thus, this study investigated the effects of long-term, dietary phthalate exposure on estrous cyclicity and fertility in female mice. Adult female CD-1 mice were fed chow containing vehicle control (corn oil) or 0.15-1500 ppm of di(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DiNP), or a mixture of phthalates (Mix) containing DEHP, DiNP, benzyl butyl phthalate, di-n-butyl phthalate, diisobutyl phthalate, and diethyl phthalate. Measurements of urinary phthalate metabolites confirmed effective delivery of phthalates. Phthalate consumption for 11 months did not affect body weight compared to control. DEHP exposure at 0.15 ppm for 3 and 5 months increased the time that the mice spent in estrus and decreased the time the mice spent in metestrus/diestrus compared to control. DiNP exposure (0.15-1500 ppm) did not significantly affect time in estrus or metestrus/diestrus compared to control. Mix exposure at 0.15 and 1500 ppm for 3 months decreased the time the mice spent in metestrus/diestrus and increased the time the mice spent in estrus compared to control. DEHP (0.15-1500 ppm) or Mix (0.15-1500 ppm) exposure did not affect fertility-related indices compared to control. However, long-term DiNP exposure at 1500 ppm significantly reduced gestational index and birth rate compared to control. These data indicate that chronic dietary exposure to phthalates alters estrous cyclicity, and long-term exposure to DiNP reduces gestational index and birth rate in mice.

Contamination of Water and Sediments of Harike Wetland with Phthalate Esters and Associated Risk Assessment

Phthalate esters (PEs) are esters that are used as plasticizers and are widely known for their contamination and toxicological effects on various environmental matrices. The present study is designed to observe the co-occurrence of phthalate esters and their ecotoxicological and human health risk assessments on Harike wetland, Ramsar, a site recognized globally, is the largest freshwater wetland in Northern India. During the winter, summer, and monsoon seasons, samples of the water and sediments were collected. These samples were then analyzed for ubiquitously detected seven PEs as per the literature survey using ultra-high performance liquid chromatography. According to the results, the total PEs content in the water sample ranged from 31.5 to 95.6 mg/L, whereas in the sediments it ranged from 35.1 to 345.2 mg/100 g dw. Prominent levels of PEs in water and sediments from the Harike wetland were discovered when compared to studies from different parts of the world. Based on drinking water consumption there is a potentially high risk of PEs especially benzyl butyl phthalate and dibutyl phthalate. Further, as per the US Environmental Protection Agency, chronic values of PEs levels in water and sediments are expected to possess a threat to sensitive organisms present in freshwater ecosystems. As far, as this is a detailed study that described the levels and ecotoxicological risks of PEs and is an important reference for the protection of aquatic organisms in the Harike wetland.