Butyl Benzyl Phthalate Research Articles

Levels, distribution, and health risk assessment of phthalic acid esters in urban surface soils of Nagpur city, India.

Surface soil samples from residential, commercial, and industrial areas of Nagpur city, India, were collected to study the levels, distribution, and impact of land use patterns on phthalic acid ester (PAEs) contamination. The Σ6PAEs concentrations in soils from residential, commercial, and industrial areas ranged between 6,493 to 13,195µg/kg, 707 to 18,446µg/kg, and 1,882 to 5,004µg/kg with medians of 10,399, 6,199, and 3,401µg/kg, respectively. Bis-2-ethylhexyl phthalate (DEHP) and dimethyl phthalate (DMP) were the dominant PAEs in the urban soils. The concentrations of DEHP and DMP were significantly greater than those in Ontario's soil quality guidelines. Among the PAEs, benzyl-butyl phthalate (BzBP) was found at relatively high concentrations (1,238 and 9,171µg/kg) at two locations (i.e., S1 and S15). The chronic toxic risk (CTR) of PAEs was below the threshold, although the risk to children through ingestion and dermal exposure routes was greater than that to adults. The CR due to BzBP and DEHP were below the threshold level; however, the CR due to DMP was > 1 × 10-6 in residential areas. The cumulative CR of the six PAEs for adults (1.33-1.41 × 10-5) and children (8.08-8.89 × 10-6) surpassed the threshold level. This study revealed that PAEs in urban soils pose a risk to public health and require immediate risk reduction strategies.

Phthalate Esters in Water and Surface Sediments of Anambra River in Dry Season: Distribution and Human Health Risks Assessment

This study investigated phthalate ester (PAE) contamination in water and sediment samples due to their persistence and potential health risks as endocrine disruptors. Sediment analysis revealed pH ranged from 5.35 to 6.72, with total organic carbon (TOC) levels varying between 0.74% and 2.56%. Water pH values were within WHO guidelines (5.5–8.5), and turbidity levels ranged from 0.60 to 1.40 NTU. Phthalate concentrations in sediment revealed Monobutyl phthalate (MBP), Diethyl phthalate (DEP), Dipentyl phthalate (DPP), Butyl benzyl phthalate (BBP), Dibutyl phthalate (DBP), and Di(2-ethylhexyl) phthalate (DEHP). Sample SA exhibited the highest levels of MBP (0.40 mg/kg) and DEP (0.93 mg/kg). In water samples, MBP peaked at 0.01 mg/kg, while DEP reached 0.03 mg/kg, with DBP (0.07 mg/kg) and DEHP (0.08 mg/kg) also detected. Phthalate contamination in water remained below harmful thresholds. A health risk assessment calculated Chronic Daily Intake (CDI) and Hazard Quotients (HQ) for both children and adults. CDI results indicated higher risks for children, with DBP (2.20E-06 mg/kg/day) and DEHP (2.46E-06 mg/kg/day) showing the greatest concern. The HQ for children was highest for DBP (0.22), though still below the risk threshold. Adults exhibited lower CDI and HQ values, with minimal non-carcinogenic risk. These findings highlight the need for continued monitoring of phthalate pollution, especially given children’s heightened vulnerability.

Content and Health Risks of Microplastics and Phthalate Esters in Bottled Water

To study the content and health risks of microplastics （MPs） and phthalate esters （PAEs） in bottled water, a quantitative analysis of MPs was conducted by using Rose Bengal staining and stereomicroscopy. Seven PAEs were quantified by using gas chromatography-triple quadrupole tandem mass spectrometry （GC-MS/MS）. The daily intake of MPs was estimated and the carcinogenic and non-carcinogenic risks of PAEs were evaluated through a health risk assessment model. The results showed that the abundance of MPs in 21 bottled waters ranged from 48 n·L-1 to 216 n·L-1 （with the median abundance of 88 n·L-1）. The majority （72.1%） of MPs were fibrous in shape, and fragments accounted for only 27.9%. The average proportion of small-sized （10-50 μm） MPs was 33.9%, and that of large-sized MPs （>500 μm） was 4.3%. Most MPs were blue. The ∑(PAEs) in bottled water was 1.15-2.47 μg·L-1 （average 1.62 μg·L-1）. PAEs detected with high frequencies （100%） included dimethyl phthalate （DMP）, diethyl phthalate （DEP）, diisobutyl phthalate （DIBP）, di-n-butyl phthalate （DBP）, and di（2-ethylhexyl） phthalate （DEHP）, while the detection frequencies of butylbenzyl phthalate （BBP） and di-n-octyl phthalate （DNOP） were relatively low. The concentrations of DBP, DEHP, and DEP were all below the standard limits for drinking water in China. The ∑(PAEs) in the migration experiments was 0.61-2.04 μg·L-1 （average 1.33 μg·L-1）. The migration amounts of DBP and DEHP were also within the allowable range under the condition of 60℃ for 10 days. Seven PAEs were detected in both the bottles and caps, and the average content of DEHP in bottles was the highest, while DBP had the highest content in caps. The estimated intake of MPs （EDI） by drinking bottled water in different age groups of humans was 2.87 n·（kg·d）-1 for adults, 3.87 n·（kg·d）-1 for children, and 5.85 n·（kg·d）-1 for infants. The carcinogenic risks of DEHP in 21 bottled water samples and the migration test were less than the maximum acceptable risk level （1×10-6）, and the non-carcinogenic risk indices （HIs） of PAEs were all less than 1, indicating no non-carcinogenic risk to humans； however, the risk value of infants and children was higher than that of adults and should not be ignored.

Exposure to benzyl butyl phthalate (BBP) leads to increased double-strand break formation and germline dysfunction in Caenorhabditis elegans.

Benzyl butyl phthalate (BBP), a plasticizer found in a wide range of consumer products including vinyl flooring, carpet backing, food packaging, personal care products, and children's toys, is an endocrine-disrupting chemical linked to impaired reproduction and development in humans. Despite evidence that BBP exposure perturbs the integrity of male and female gametes, its direct effect on early meiotic events is understudied. Here, using the nematode Caenorhabditis elegans, we show that BBP exposure elicits a non-monotonic dose response on the rate of X-chromosome nondisjunction measured using a high-throughput screening platform. From among the range of doses tested (1, 10, 100 and 500 μM BBP), we found that 10 μM BBP elicited the strongest effect on the germline, resulting in increased germ cell apoptosis and chromosome organization defects. Mass spectrometry analysis shows that C. elegans efficiently metabolizes BBP into its primary metabolites, monobutyl phthalate (MBP) and monobenzyl phthalate (MBzP), and that the levels of BBP, MBP, and MBzP detected in the worm are within the range detected in human biological samples. Exposure to 10 μM BBP leads to germlines with enlarged mitotic nuclei, altered meiotic progression, activation of a p53/CEP-1-dependent DNA damage checkpoint, increased double-strand break levels throughout the germline, chromosome morphology defects in oocytes at diakinesis, and increased oxidative stress. RNA sequencing analysis indicates that BBP exposure results in the altered expression of genes involved in xenobiotic metabolic processes, extracellular matrix organization, oocyte morphogenesis, meiotic cell cycle, and oxidoreduction. Taken together, we propose that C. elegans exposure to BBP leads to increased oxidative stress and double-strand break formation, thereby compromising germline genomic integrity and chromosome segregation.

Butyl benzyl phthalate induces neurotoxicity in Eisenia fetida: Mechanisms revealed by biochemical and metabolomic analyses

Phthalates, particularly butyl benzyl phthalate (BBP), are ubiquitous environmental contaminants with potential neurotoxic effects. However, their impact on soil organisms, especially earthworms (Eisenia fetida), remains poorly understood. The current study investigated the neurotoxic effects of BBP on Eisenia fetida in artificial and red soils using an integrated approach combining biochemical assays, metabolomics, and molecular docking. Earthworms were exposed to 0, 1, and 10 mg kg−1 BBP for 14 and 28 days. Biochemical assays revealed significant increases in oxidative stress markers and disruptions in neurotransmission-related enzyme activities. Metabolomic analysis of the cerebral ganglia identified alterations in energy metabolism, lipid metabolism, and neuroactive ligand-receptor interaction signaling pathways. Molecular docking studies corroborated these findings, showing strong interactions between BBP and essential neuronal proteins, particularly the sodium pump. The integration of these data suggests that BBP-induced neurotoxicity in Eisenia fetida is primarily mediated by calcium signaling pathway dysfunction and calcium homeostasis imbalance. Notably, neurotoxic effects were more pronounced in red soil than in artificial soil, highlighting the importance of considering soil type in ecotoxicological assessments. The current study provides novel insights into the mechanisms of BBP-induced neurotoxicity in soil invertebrates and underscores the potential ecological risks associated with phthalate contamination in agricultural environments.

In-silico characterization of a hypothetical protein of Sulfobacillus sp. hq2 for degradation of phthalate diesters

Phthalate plasticizers are hazardous compounds capable of causing endocrine disruption, cancers, and developmental disorders. Phthalate diesters are commonly used plasticizers in plastic products (PVC pipes) that leach out into the environment due to changes in temperature, pressure, and pH, posing harmful effects on different life forms. Bioremediation of phthalate diesters utilizing bacterial esterase has been recognized as an efficient approach but few effective esterases capable of degrading a wide range of phthalate diesters have been identified. Further, the thermostability of these esterases is a highly desirable property for their applications in diverse in-situ conditions. In this present in-silico study a hypothetical protein (POB10642.1) as a high-potential esterase from a thermostable strain of Sulfobacillus sp. hq2 has been characterized. Analysis revealed a significant sequence identity of 42.67 % and structural similarity (RMSD 0.557) with known phthalate diester degrading EstS1 esterase and a high Tm range of 55–66 °C. Structural analysis revealed the presence of two cavities on the surface mediating toward the catalytic site forming a catalytic tunnel. The enzyme POB10642.1 has significant molecular docking binding energies in the range of −5.4 to −7.5 kcal/mol with several phthalate diesters, including Diethyl phthalate, Dipropyl phthalate, Dibutyl phthalate, Dipentyl phthalate, Dihexyl phthalate, Benzyl butyl phthalate, Dicyclohexyl phthalate, and Bis(2-ethylhexyl) phthalate. High stability of binding during 100 ns molecular dynamics simulations revealed efficient and stable binding of the enzyme with a wide range of phthalate diesters at its active site, demonstrating the ability of the identified esterase to interact with and degrade diverse phthalate diesters. Therefore, POB10642.1 esterase can be an efficient candidate to be utilized in the development of enzyme-based bioremediation technologies to reduce the toxic levels of phthalate diesters.

Bioaccessibility of plastic-related compounds from polymeric particles in marine settings: Are microplastics the principal vector of phthalate ester congeners and bisphenol A towards marine vertebrates?

Marine vertebrates are known to ingest significant amounts of microplastics (MPs). Once ingested, MPs might cause gastrointestinal injuries and serve as a path of harmful plastic components, such as phthalate esters (PAEs) and bisphenol A (BPA) in the food chain. However, there is a lack of standardized in-vitro methods capable of simulating fish uptake of chemicals from MPs in the environment as potential vectors of such contaminants. In this work, leaching and in-vitro oral bioaccessibility testing of PAEs and BPA from MPs were conducted batchwise using artificial seawater and gut fluids mimicking gastric, intestinal, and gastrointestinal compartments of marine vertebrates at physiological temperature. The environmental and physiologically relevant extraction tests were applied to medium-density polyethylene (PE) and polyvinyl chloride (PVC) certified reference materials containing eight PAEs of varying hydrophobicity, namely, dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate, benzylbutyl phthalate, diethylhexyl phthalate, di-n-octyl phthalate, diisononyl phthalate and diisodecyl phthalate, and BPA (only in PE) as MP surrogates with realistic analyte concentrations of additives for primary MPs. The analysis of the leachates/gut fluid extracts was performed via dilute-and-shoot by ultra-high performance liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Only the most hydrophilic compounds, i.e. DMP, DEP and BPA, were found to get released significantly in saline waters, and exhibited the highest oral bioaccessibility rates (34–83 %). Based on our results, a dual-compartment physiologically relevant gastrointestinal test is recommended for appropriate estimation of fish bioaccessibility. The fish daily intakes of DMP, DEP and BPA from MPs, and seawater ingestion as well were estimated using several contamination scenarios (10th percentile as the low level, 50th percentile as the medium level and 90th percentile as the high level) based on probabilistic distributions and cumulative probability curves of measured environmental concentrations of (i) MPs in seawater throughout the world, (ii) DMP, DEP and BPA in beached MPs and those sampled in the open ocean (including both incurred and adsorbed contaminants), and (iii) DMP, DEP and BPA in seawater as reported in recent literature. Under a medium-level concentration scenario (50th percentile) in marine settings, and taking the gastrointestinal bioaccessibility factor into account, the daily intake of DMP, DEP and BPA from MPs accounted for a mere 0.02 % of the waterborne contribution. Hence, the ingestion of MPs should not be considered the primary route of fish exposure to BPA and the most polar PAEs in marine environments. However, more studies on the local and the global scales for mass concentrations of MPs and additives in marine settings are needed for further confirmation of our findings.

Epigenetic Changes in the HTR8 and 3A-sub E placental Cell Lines Exposed to Bisphenol A and Benzyl Butyl Phthalate.

Bisphenol A and phthalate are known endocrine disruptors and capable of inducing epigenetic changes in the human population. However, their impact on the placenta is less well studied. Our objective was to measure the effect of exposure to bisphenol A and benzyl butyl phthalate in first-trimester HTR8-SVneo and third-trimester 3A-sub E trophoblast cells by profiling the DNA methylation pattern of the imprinting control region of the IGF2 (insulin-like growth factor) and H19 genes. Human placental HTR8-SVneo and 3A-sub E cell lines were treated with two sub-lethal concentrations of bisphenol A and benzyl butyl phthalate. Demethylating agent, 5-azacytidine, was used as a positive control. Cells were harvested on post-treatment days 1 and 4. The methylation profile of six CpG dinucleotide sites, part of the CTCF 6 binding site of the IGF2/H19 imprinting control region, was determined by pyrosequencing. In the first-trimester HTR8-SVneo cell line, we observed a significant increased methylation of the CpG sites 3, 4 when treated with a high concentration of bisphenol A or benzyl butyl phthalate while increased methylation at site 6 for both high and low dose treatment on day 4. Demethylation of the CpG sites 1, 4, and 6 was observed when treated with 5-azacytidine on day 4. In the third-trimester 3A-sub E cell line, no significant changes in the methylation profile were observed under any treatment conditions. The results of this study demonstrate the capability of epigenetic changes in human placenta cells induced by bisphenol A and benzyl butyl phthalate. The observed methylation changes only in the first-trimester HTR8-SVneo cells phthalate may reflect a window of epigenetic susceptibility related to these environmental toxicants.

Whole-cell biocatalysis for phthalate esters biodegradation in wastewater by a saline soil bacteria SSB-consortium

Phthalic acid esters (PAE) are widely used as plasticizers and have been classified as ubiquitous environmental contaminants of primary concern. PAE have accumulated intensively in surface water, groundwater, and wastewaters; thus, PAE degradation is essential. In the present study, the ability of a saline soil bacteria (SSB)-consortium to degrade synthetic wastewater-phthalates with alkyl chains of different lengths, such as diethyl phthalate (DEP), di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), and di (2-ethylhexyl) phthalate (DEHP) was characterized. A central composite design-response surface methodology was applied to optimize the degradation of each phthalate, where the independent variables were temperature (21–41 °C), pH (5.3–8.6) and PAE concentration (79.5–920.4 mg L−1), and Gas Chromatography-Mass Spectrometry was used to identify the metabolites generated during phthalate degradation. Optimal conditions were 31 °C, pH 7.0, and an initial PAE concentration of 500 mg L−1, where the SSB-consortium removed 84.9%, 98.47%, 99.09% and 98.25% of initial DEP, DBP, BBP, and DEHP, respectively, in 168h. A first-order kinetic model explained - the biodegradation progression, while the half-life of PAE degradation ranged from 12.8 to 29.8 h. Genera distribution of the SSB-consortium was determined by bacterial meta-taxonomic analysis. Serratia, Methylobacillus, Acrhomobacter, and Pseudomonas were the predominant genera; however, the type of phthalate directly affected their distribution. Scanning electron microscopy analysis showed that high concentrations (1000 mg L−1) of phthalates induced morphological alterations in the bacterial SSB-consortium. The metabolite profiling showed that DEP, DBP, BBP, and DEHP could be fully metabolized through the de-esterification and β-oxidation pathways. Therefore, the SSB-consortium can be considered a potential candidate for bioremediation of complex phthalate-contaminated water resources.

Occurrence, distribution and risk assessment of phthalate esters in dust deposited in the outdoor environment of Yazd industrial park using Monte Carlo simulation

In this study, the distribution of eight phthalate esters (PAEs), namely (dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), butyl benzyl phthalate (BBP), bis (2-ethylhexyl) phthalate (DEHP), and di-n-octyl phthalate (DnOP)) were examined across fifteen sampling stations in Yazd industrial Park. All the PAEs in dust deposited in the outdoor environment were analyzed using a Gas-mass chromatography (GC-MS/MS) device. Both probabilistic and deterministic approaches were utilized to assess the non-carcinogenic and carcinogenic health risks for adult occupational population groups. These risks were associated with three exposure pathways: inhalation, ingestion, and dermal exposure to six phthalates in the dust samples. The findings revealed, among the fifteen sampling stations, highest and lowest concentrations of the PAEs in dust deposited in the outdoor environment were observed in S8 and S6, with BEHP (326.21 ± 4.35) μg/g and DMP (0.00 ± 0.02) μg/g, respectively. The total hazard index (HI) values were below one in all samples, indicating that the combined non-carcinogenic health risk from exposure to phthalates via inhalation, ingestion, and dermal pathways is within acceptable levels in each studied area. The total cancer risk (CR) values for BBP across all exposure routes were consistently low, with magnitudes ranging from 10- x 10−15to 10 x 10−11. The order of cancer risk from phthalate exposure in outdoor environments was ingestion > dermal > inhalation. The sensitivity analysis (SA) results indicated that the influential parameters in the carcinogenic risk in adult occupational population groups were concentration for inhalation and dermal pathways, as well as ingestion rate for the ingestion pathway. The result of this study provides new insight in to PAEs pollution and risk assessments related to the dust deposited in the outdoor environment of industrial Park. Furthermore, this finding is beneficial to the controlling the exposure and promoting steps to reduce PAEs contamination and manage health in the industrial area.

Application of solvent-based dissolution for the recycling of polyvinylchloride flooring waste containing restricted phthalate plasticizers

The applicability of a new recycling method for extracting contaminants from polymers, dissolution-based recycling, was tested on a polyvinylchloride equipped with diethylhexyl phthalate, benzylbutyl phthalate, di-isobutyl phthalate, di-n‑butyl phthalate, originating from post-consumer flooring waste. Due to European restrictions on these ortho-phthalate diester-based plasticizers, the mechanical recycling of plasticized polyvinylchloride is no longer feasible. In this study, we have shown that dissolution and consecutive purification of the polymer eliminate 99.9 % of diethylhexyl phthalate's initial concentration at the laboratory scale. The impact of different process parameters, e.g., temperature, agitation, and extraction kinetics, have been tested. The findings were transferred to a technical scale of 5 kg/d, using a multi-step extraction in counter-flow mode. An elimination of 99.4 % of diethylhexyl phthalate initial concentration has been achieved, which fulfills legal requirements. These promising results showed the technical feasibility and served as a preliminary stage for further up-scaling to technical readiness level 6.

Phthalates on indoor surfaces and associated exposure via surface touch behavior: Observation in university dormitories and its implications

Phthalates are typical emerging indoor pollutants and ubiquitously distributed in the indoor air, settled dust and on surfaces. Phthalates have the potential to be transported by human hands through surface touch behaviors. Although the contribution of subsequent exposure via hand-to-mouth contact in real indoor environments has not been thoroughly characterized, it is an important factor to consider. In this study, six commonly-used 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)) were measured in surface wipes, air and dust samples collected from university dormitories. Video-cameras were used to monitor occupants’ real surface touch behaviors. Primary surfaces being touched included desks, cellphones, keyboards and computer mice, with averaged touch frequencies ranging from 10.4 h−1 to 25.4 h−1. Phthalate levels on computer mice were the highest, with DEHP being present as the most predominant compound (mean: 2621 μg/m2). Exposures via inhalation, dust ingestion, dermal absorption and hand-to-mouth contact were further estimated using Monte-Carlo simulations. The results suggest that the exposure resulting from surface touching and subsequent hand-mouthing could contribute 35 %–55 % to total exposure for targeted phthalates, which were generally higher than intakes via dust ingestion. This study provides a better understanding of phthalate transfer through surface touch behavior, and highlights the significance of hand-to-mouth contact exposure in indoor environments.

Biochemical and transcriptomic analyses reveal the toxicological response and potential mechanism of butyl benzyl phthalate in zebrafish gills

Butyl benzyl phthalate (BBP), a common phthalate plasticizer, is frequently detected in aquatic environments. However, there has been relatively little research on its effects on gill-related responses. This study exposed adult zebrafish to BBP concentrations ranging from 5 to 500 μg/L for 28 days, specifically investigating its toxicity in the gills. Assessment of oxidative stress biomarkers and gene expression related to apoptosis and mitochondria was conducted. Results demonstrated that exposure to 500 μg/L of BBP disrupted the antioxidant defense system, leading to lipid peroxidation and DNA damage. Moreover, the expression level of the caspase-3 gene exhibited an approximate two-fold increase, whereas the expression of 18rs-rrn decreased by 50 % on day 28. Gene Ontology enrichment analysis indicated suppressed expression of antioxidant and metabolic process terms, alongside inhibition of metabolism, immune, and signal transduction-related pathways. This study offers novel insights into the toxic effects and mechanisms of BBP on fish, providing valuable data for assessing environmental risks linked to BBP contamination and advocating for its management in aquatic ecosystems.

Development and validation of a new analytical method for the determination of plasticizers in bee pollen

The determination of plasticizers in bee pollen may be important not only to evaluate the contamination of the hive environment, but also to verify the safety for consumers of this food supplement, since to date it has not been studied. Therefore, a new analytical methodology for the determination of nine plasticizers (phthalate esters: di-(2-ethylhexyl) phthalate, dibutyl phthalate, dimethyl phthalate, diethyl phthalate, benzyl butyl phthalate, and di-n-octyl phthalate; diphenyl ethers: 4-bromodiphenyl ether and 4-chlorodiphenyl ether; adipate: bis(2-ethylhexyl) adipate) in bee pollen using gas chromatography-mass spectrometry was developed. An efficient sample treatment (modified QuEChERS, quick, easy, cheap, effective, rugged & safe) is proposed (with average analyte recoveries between 77 % and 104 %) involving extraction with acetonitrile followed by a dispersive solid phase extraction (enhanced matrix removal lipid sorbent). Chromatographic analysis (<21 min) was performed in an Agilent HP-5MS column under programmed temperature conditions, and analyses were performed in selected ion monitoring mode. The method was validated in terms of selectivity, limits of detection (0.2–17.2 μg kg−1) and quantification (0.5–57.5 μg kg−1), linearity, matrix effect, trueness, and precision (relative standard deviation < 15 %). Finally, an analysis of thirty samples from different sources (commercial or experimental apiaries) revealed the presence of residues of five plasticizers in all samples. Quantification was possible in several cases, with overall concentrations ranging from 0.056 to 3.152 mg kg−1. This study not only reports for the first time the presence of some plasticizers in bee pollen, but also corroborates the usefulness of bee pollen as bioindicator of environmental contamination.

Quantitative label-free proteomic analysis of mouse ovarian antral follicles following oral exposure to a human-relevant mixture of three phthalates.

Dibutyl phthalate (DBP), di-2-ethylhexyl phthalate (DEHP), and benzyl butyl phthalate (BBP) are used in personal and medical care products. In the ovary, antral follicles are essential for steroidogenesis and ovulation. DBP, BBP, and DEHP are known to inhibit mouse antral follicle growth and ovulation in vitro, and associate with decreased antral follicle counts in women. Given that the in vivo effects of a three-phthalate mixture on antral follicles are unknown, we evaluated the effects of a human-relevant mixture of DBP, BBP, and DEHP on ovarian follicles through proteome profiling analysis. Adult CD-1 female mice were fed corn oil (vehicle), or two dose levels of a phthalate mixture based on estimated exposures in general (32 µg/kg/d; PHT 32) and occupationally exposed (500 µg/kg/d; PHT 500) populations for 10 d. Antral follicles (>250 µm) were isolated and subjected to proteome profiling via label-free tandem mass spectrometry. A total of 5,417 antral follicle proteins were detected, of which 194 were differentially abundant between vehicle and PHT 32, and 136 between vehicle and PHT 500. Bioinformatic analysis revealed significantly different responses between the two phthalate doses. Protein abundance differences in the PHT 32 exposure mapped to cytoplasm, mitochondria, and lipid metabolism; whereas those in the PHT 500 exposure mapped to cytoplasm, nucleus, and phosphorylation. When both doses altered proteins mapped to common processes, the associated predicted transcription factors were different. These findings provide novel mechanistic insight into phthalate-associated, ovary-driven reproductive outcomes in women.

Phthalate esters in water and sediment of Asunle stream of Obafemi Awolowo University, Ile-Ife, Nigeria: Distribution and human health risks

This study determined the concentrations and seasonal variations of phthalate esters (PAEs) in water and sediment samples of the receiving stream within the vicinity of the Obafemi Awolowo University, Ile-Ife dumpsite. The objective of this study was to evaluate the pollution status of the study area by determining the levels of PAEs in water and sediment samples. This assessment aimed to understand the presence and extent of phthalate ester pollution in the study area. Water and sediment samples were collected from six selected stations along the receiving stream for analysis that included one upstream and five downstream points for four months during both wet season and dry season. The liquid-liquid extraction (LLE) method was employed to extract PAEs from the water samples collected, while microwave extraction method was optimized for their extraction in sediment samples. Quantification of the PAEs was conducted using Gas Chromatography coupled with a quadrupole Mass Spectrometer (GC-MS) in this study. The mean concentration of phthalates varied in the water and sediment samples. In the water samples, the phthalate concentrations ranged from 1.88 ± 0.16 μg/L for diethyl phthalate to 15.74 ± 0.33 μg/L for di(2-ethylhexyl phthalate) (DEHP). Also, butylbenzyl phthalate and DEHP will pose potential carcinogenic risks when used for bathing and drinking purposes, due to their relatively higher carcinogenic risk values. In the sediment samples, the concentrations ranged from 0.09 ± 0.02 mg/kg for dimethyl phthalate to 14.27 ± 1.76 mg/kg for di(2-ethylhexyl phthalate). The seasonal variation analysis of PAE congeners revealed that higher levels were observed during the dry season in the collected samples. The study concluded that the stream was heavily contaminated with di(-2-ethylhexyl)phthalate at levels that gave cause for human health and environmental concerns.

Distribution and Risk Assessment of Phthalate Esters in Refuse Dumpsite Soils of Obafemi Awolowo University, Ile-Ife, Nigeria

ABSTRACT The levels, seasonal variation, and lateral and vertical migration of PAEs in refuse dumpsite soils of Obafemi Awolowo University, Ile-Ife, Nigeria, were investigated in this research. This was done to calculate the health hazards linked to contact with these soils. Soil samples were collected using soil auger during dry and wet seasons at varying soil depths and different intervals of 50, 100, and 117 m between dumpsite and the receiving stream. Microwave extraction method was optimized to extract PAEs from soil samples. Chromatographic quantifications were done using Gas Chromatography connected to a quadrupole Mass Spectrometer. Di(2-ethylhexyl phthalate) possessed the most significant concentration of 49.83 ± 0.49 mg kg−1 in December. The cumulative levels of butylbenzyl phthalate and di (2-ethylhexyl phthalate) accounted for more than 90% of total PAEs in dumpsite soils. Dimethyl phthalate, diethyl phthalate, and dibutyl phthalate had higher levels during wet season as opposed to the high levels of butylbenzyl phthalate and di(2-ethylhexyl phthalate) during dry season. PAEs exhibited a potential to affect groundwater quality based on their vertical distribution. Plastic pollution was identified as the primary source of PAEs in the dumpsite soils. The health risk evaluation indicated that there were no non-carcinogenic and carcinogenic health risks linked to exposure to the aforementioned phthalates.

Soft plastic fishing lures as a potential source of chemical pollution - Chemical analyses, toxicological relevance, and anglers’ perspectives

Soft plastic lures (SPLs) are commonly used artificial lures in recreational angling. Anglers regularly lose SPLs while fishing and there is little knowledge about the environmental impacts of lost SPLs. As with other plastic items, SPLs contain phthalates and other persistent additives that may leach into water. In this study, 16 randomly chosen SPLs of common models were analyzed for the leaching of persistent, water-soluble plastic additives, including phthalates. The estrogenicity of sample extracts from a subsample of 10 SPLs was assessed using luciferase reporter gene bioassays. Over a period of 61 days, 10 of the 16 SPLs leached the targeted phthalates dimethyl phthalate (DMP), diethyl phthalate (DEP), benzyl butyl phthalate (BBP) and di-n-butyl phthalate (DnBP) at median detectable concentrations ranging from 10 ng/g sample BBP to a median of 1001 ng/g DMP as well as 45 persistent, mobile, and toxic (PMT) plastic additives. DEP was detected most frequently in 8 SPLs, followed by BBP (2 SPLs), DMP (2 SPLs) and DnBP (1 SPL). The extract from one SPL with comparatively low phthalate and PMT plastic additive levels was active in the bioassay, indicating high endocrine-disruptive potential, presumably due to unknown additives that were not among the target substances of the methodology used in this study. The study was supplemented by a mail survey among anglers, in which attitudes of anglers towards SPLs were investigated. The survey indicated that SPL loss is a common event during angling. Most participants were concerned about potential ecological impacts of SPLs, wanted the ingredients of SPLs to be labelled and supported legal restrictions concerning toxic ingredients of SPLs. The study shows that SPLs are a potential source of environmental pollution, may pose human health risks and need further investigation, considering the frequent use of SPLs in recreational angling.

Biochar mitigates the postponed bioavailability and toxicity of phthalic acid esters in the soil

Observed nowadays wide pollution of the environment with microplastic and phthalic acid esters (PAEs) (such as dimethyl phthalate, DMP; diethyl phthalate, DEP; dibutyl phthalate, DBP; benzyl butyl phthalate, BBP; di-(2-ethylhexyl) phthalate, DEHP and di-n-octyl phthalate, DNOP) is a result of their increased production and usage. Weak bonding with polymer matrix enables their easier mobilization in the environment and increased bioavailability. The aim of the presented studies was the estimation of the fate of six priority PAEs in the soil-vegetable system and the application of biochar to immobilize PAEs in the soil preventing their bioavailability to lettuce. Both the acute (one full lettuce development period) and prolongated effect (lettuce cultivated after 10 weeks from the first PAEs contamination) were estimated to examine the long-time exposure under crop rotation. The addition of 1 % of corn-derived biochar immobilized PAEs in the soil efficiently (up to 4 times increased concentration) with the following order: DBP < DEP < DMP < DEHP < DNOP < BBP. Bioavailable PAEs were determined in lettuce roots (DMP, BBP, DEHP), and lettuce leaves (DEP, DBP, DNOP) but the presence of biochar lowered their content. PAEs, although not available for lettuce, were available for other organisms, confirming that the bioavailability or lack of nutrients is of great importance in PAEs-polluted soil. In long-time experiments, without biochar amendment, all PAEs were 3–12 times more bioavailable and were mainly accumulated in lettuce roots. The biochar addition significantly reduces (1.5–11 times) PAEs bioavailability over time. However, the PAEs content in roots remained significantly higher in samples with crop rotation compared to samples where only lettuce was grown. The results confirmed that biochar addition to the soil reduces their bioavailability and mobility inside the plant, limiting their transport from roots to leaves and reducing the exposure risk but confirming that lettuce leaves may be a safe food when cultivated in PAEs-polluted soil.

Extralong hot-spots sensor for SERS sensitive detection of phthalate plasticizers in biological tear and serum fluids.

Phthalate plasticizers (PAEs) illegally used in food pose a great threat to human health. A new and efficient sensing platform for the sensitive detection of the PAE residues in biological fluids needs to be designed and developed. Here, we report a simple and reliable surface-enhanced Raman spectroscopy (SERS) active platform with extralong hot spots of Au nanobipyramids@Ag nanorods (Au NBPs@Ag NRs) for the rapid and sensitive detection of PAEs in biological fluids. To achieve high activity, Au NBPs@Ag NRs with different shell lengths were fabricated by controlling the synthesis conditions, and the corresponding SERS properties were investigated by using crystal violet (CryV) and butyl benzyl phthalate (BBP). The experimental results showed that a longer shell length correlated to greater Raman activity, which was confirmed by finite-difference time-domain (FDTD) electromagnetic simulation. More importantly, the extralong hot spots of the Au NBPs@Ag NR SERS-active substrate showed excellent homogeneity and reproducibility for the CryV probe molecules (6.21%), and the detection limit was 10-9M for both BBP and diethylhexyl phthalate (DEHP). Furthermore, through the standard addition method, an extralong hot spots SERS substrate could achieve highly sensitive detection of BBP and DEHP in serum and tears fluids, and the detection limit was as low as 3.52 10-8M and 2.82 10-8M. Therefore, the Au NBPs@Ag NR substrate with an extraordinarily long surface is efficient and versatile, and can potentially be used for high-efficiency sensing analysis in complex biological fluids.