Concentrations Of Dibutyl Phthalate Research Articles

Developmental toxicity and mechanism of dibutyl phthalate and alternative diisobutyl phthalate in the early life stages of zebrafish (Danio rerio)

Diisobutyl phthalate (DiBP), is widely chemical replacement for Dibutyl phthalate (DBP). Although DBP and DiBP have been detected in surface water worldwide, few studies to date have systematically assessed the risks of DBP and its alternatives to aquatic organisms. The present study compared DBP and DiBP for their individual and joint toxicity as well as thyroid hormone levels in zebrafish embryo. Transcripts of key genes related to the hypothalamic-pituitary-thyroid (HPT) axis were investigated in developing zebrafish larvae by application of real time polymerase chain reaction. The median half-lethal concentrations of DBP and DiBP to zebrafish at 96 h were 0.545 mg L−1 and 1.149 mg L−1, respectively. The joint toxic effect of DBP–DiBP (0.25–0.53 mg L−1) with the same ratio showed a synergistic effect. Thyroid hormones levels increased with exposure to 10 μg L−1 of DBP or 50 μg L−1 of DiBP, and exposure to both compounds significantly increased thyroid gland-specific transcription of thyroglobulin gene (tg), hyronine deiodinase (dio2), and transthyretin (ttr), indicating an adverse effect associated with the HPT axis. Molecular docking results indicated that DBP (−7.10 kcal/M and −7.53 kcal/M) and DiBP (−6.63 kcal/M and −7.42 kcal/M) had the same docking energy with thyroid hormone receptors. Our data facilities an understand of potential harmful effects of DBP and its alternative (DiBP).

Levels of Phthalate Acid Esters in Carbonated Soft Drinks Bottled in Polyethylene Terephthalate (PET) Bottles Kept under Various Storage Conditions in Mwanza City, Tanzania

Background: Carbonated soft drinks (CSD), packaged in PET (polyethylene terephthalate) bottles, are among the most widely consumed non-alcoholic beverage globally. People of all ages enjoy CSDs for their flavour, mouthfeel, crispness, freshness, and capacity to both quench thirst and provide mental refreshment. Terephthalic acid, ethylene glycol, and other additives such as phthalates are the materials used to make these PET bottles. Several studies have demonstrated that phthalates may migrate into packaged goods and, when consumed, can cause several ill-health conditions to humans. Type II diabetes, obesity, asthma, male and female reproductive disorders, tumours (including breast cancer), pituitary, hypothalamic, and peripheral hormone disorders, behavioral issues, and neurodevelopmental disorders are among the health issues reported to be associated with phthalates. Objective: This study aimed to ascertain the presence and concentration of phthalates in PET bottled carbonated soft drinks produced in Mwanza City, and to examine the effects of various storage conditions on the migration of these contaminants into the product. Methods: Liquid-liquid extraction, clean-up techniques, and chromatographic analysis were used as the methods of determination to identify and quantify the specific phthalates compounds. Results: The findings demonstrated that after being stored outdoors for four to six months, the migration, especially for dibutyl phthalate (DBP) and di [2-ethylhexyl] phthalate (DEHP), became more apparent. After two, four, and six months of indoor storage, there was no appreciable change in the mean concentrations of DMP (dimethyl phthalate), DEP (diethyl phthalate), DBP (dibutyl phthalate), and DEHP for either brand in this study. Compared to indoor storage, the DBP and DEHP migration increased by up to 24-fold when the two brands were kept outdoors for four and six months. Thus, the safety and quality of carbonated soft drinks were seriously compromised by the phthalate compounds from the PET bottles that these companies were using. Conclusion: The study's conclusions show that PET packaging, which is influenced by the bottle manufacturing process and raw material formulations for packages of the studied CSDs, are responsible for the migration of phthalates into the products. The storage conditions and time are established to be the primary causes of phthalates migration in bottled carbonated soft drinks. Though the migration figures in this study are lower than those of the other studies from different locations that were compared, it is important to remember that these compounds may interfere with hormones even in small quantities.

A generalizable sensing platform based on molecularly imprinted polymer-aptamer double recognition and nanoenzyme assisted photoelectrochemical-colorimetric dual-mode detection

Developing highly sensitive and selective methods that incorporate specific recognition elements is crucial for detecting small molecules because of the limited availability of small molecule antibodies and the challenges in obtaining sensitive signals. In this study, a generalizable photoelectrochemical-colorimetric dual-mode sensing platform was constructed based on the synergistic effects of a molecularly imprinted polymer (MIP)-aptamer sandwich structure and nanoenzymes. The MIP functionalized peroxidase-like Fe3O4 (Fe3O4@MIPs) and alkaline phosphatase mimic Zr-MOF labeled aptamer (Zr-mof@Apt) were used as the recognition elements. By selectively accumulating dibutyl phthalate (DBP), a small molecule target model, on Fe3O4@MIPs, the formation of Zr-MOF@Apt-DBP- Fe3O4@MIPs sandwich structure was triggered. Fe3O4@MIPs oxidized TMB to form blue-colored oxTMB. However, upon selective accumulation of DBP, the catalytic activity of Fe3O4@MIPs was inhibited, resulting in a lighter color that was detectable by the colorimetric method. Additionally, Zr-mof@Apt effectively catalyzed the hydrolysis of L-Ascorbic acid 2-phosphate sesquimagnesium salt hydrate (AAPS), generating ascorbic acid (AA) that could neutralize the photogenerated holes to decrease the photocurrent signals for PEC sensing and reduce oxTMB for colorimetric testing. The dual-mode platform showed strong linearity for different concentrations of DBP from 1.0 pM to 10 μM (PEC) and 0.1 nM to 0.5 μM (colorimetry). The detection limits were 0.263 nM (PEC) and 30.1 nM (colorimetry) (S/N = 3), respectively. The integration of dual-signal measurement mode and sandwich recognition strategy provided a sensitive and accurate platform for the detection of small molecules.

Ecological risk assessment and phthalate ester concentrations in sediment samples from Ilorin metropolis, North Central Nigeria

The presence of phthalate esters (PEs) in the environment, common components of plastics and consumer products, is causing increasing anxiety over the prospect of negative effects on ecosystems and human well-being. Ilorin metropolis, situated in north-central Nigeria, is not immune to this environmental challenge. Recognizing the urgent need for a thorough evaluation, this study is dedicated to determining the levels and risk assessment of five PEs (diethyl phthalate (DEP), dibutyl phthalate (DBP), benzylbutyl phthalate (BBP), di-n-octyl phthalate (DnOP), and di-(2-ethylhexyl) phthalate (DEHP)) in seven sediment samples obtained from farms and discharge pipes across Ilorin metropolis. It was observed that the total levels of the five phthalates varied from 1.0126 to 27.7196 ng/g in the sediment. Among them, DBP exhibited the highest concentration in sediment samples, with an average value of 12.87 ng/g, followed by DEHP (average, 10.87 ng/g), DnOP (1.865 ng/g), BBP (1.099 ng/g), and DEP (1.042 ng/g). Significant positive correlations were observed between the concentrations of DBP, DEP, and DEHP and the physico-chemical parameters of the sediments. Ecological risk assessment revealed that only DEP likely posed a minimal risk. While the findings indicate that the phthalates pose minimal or no risk, there is a need for comprehensive phthalate monitoring in these locations to minimize the influx of these substances. This proactive measure is essential to prevent potential disruptions to the delicate equilibrium of the ecosystem, which could result in a catastrophic loss of biodiversity.

Phthalates in marine sediment, water and the cockle Anadara antiquata on the coast of Tanzania

Phthalates are a group of chemicals used as plasticisers, and are easily released into the environment, where they degrade over time. We investigated the concentrations of phthalates in sediments, seawater, and the cockle Anadara antiquata from beaches at Dar es Salaam, Mtwara, Tanga and Zanzibar in Tanzania. A dispersive liquid-liquid microextraction method was used to extract analytes from samples, whereafter they were analysed with a gas chromatograph coupled to a mass spectrophotometer. Concentrations of diisobutyl phthalate (DiBP), dibutyl phthalate (DBP) and Bis(2-ethylhexyl) phthalate (DEHP) were determined. DiBP concentrations were highest at Dar es Salaam (11.5 - 12.4 ng/mL in seawater; 11.5 - 13.6 ng/g dry weight in sediments), compared to the other three sites, where minimum and maximum concentrations in sediments were 3.5 ng/g dw (Mtwara) and 10.7 ng/g dw (Tanga). DBP concentrations were also highest at Dar es Salaam (12.4 - 20.6 ng/mL in seawater; 12.1 - 18.7 ng/g dw in sediments) compared to 2.7 (minimum, Mtwara) and 11.2 ng/g dw (maximum, Tanga). DEHP at Dar es Salaam ranged from un-detected to 12.6 ng/mL in seawater and to 12.6 ng/g dw in sediments. It was further revealed that A. antiquata from Kawe Beach (Dar es Salaam) had higher concentrations of DiBP, DBP, and DEHP compared to other sites. Monitoring of phthalate concentrations will indicate pollution hotspots and trends in the region.

HBM4EU e-waste study: Occupational exposure of electronic waste workers to phthalates and DINCH in Europe

Workers involved in the processing of electronic waste (e-waste) are potentially exposed to toxic chemicals, including phthalates and alternative plasticizers (APs). Dismantling and shredding of e-waste may lead to the production of dust that contains these plasticizers. The aim of this study, which was part of the European Human Biomonitoring Initiative (HBM4EU), was to assess the exposure to phthalates (e.g. di-(2-ethylhexyl) phthalate (DEHP), diethyl phthalate (DEP), di-butyl phthalate (DBP), butyl-benzyl phthalate (BBzP), di-isononyl phthalate (DiNP), di-isodecyl phthalate (DiDP) and cyclohexane-1,2-dicarboxylic di-isononyl ester (DINCH) in e-waste workers from ten European companies. This was achieved by (i) analysing urine samples from 106 e-waste workers collected at the beginning and at the end of the work week, (ii) comparing these with urine samples from 63 non-occupationally exposed controls, and (iii) analysing settled floor dust collected in e-waste premises. Significantly higher urinary concentrations of seven out of thirteen phthalates and DINCH metabolites were found in the e-waste workers compared to the control population. However, no significant differences were found between pre- and post-shift concentrations in the e-waste workers. Concentrations of DBP, DEHP and DiDP in dust were weakly to moderately positively correlated with their corresponding urinary metabolite concentrations in the e-waste workers (Spearman's ρ = 0.4, 0.3 and 0.2, respectively). Additionally, significantly lower urinary concentrations of nine phthalates and DINCH metabolites were found in e-waste workers using respiratory protective equipment (RPE) during their work activities, reflecting the potential benefits of RPE to prevent occupational exposure to phthalates and DINCH. The estimated daily intake (EDI) values obtained in this study were lower than the corresponding tolerable daily intake (TDI) adopted by the European Food Safety Authority (EFSA) for the general population, suggesting that the risk for negative health consequences in this population of e-waste workers from exposure to phthalates and DINCH is expected to be low. This was confirmed by the urinary metabolite concentrations of all workers being lower than the HBM4EU guidance values derived for the occupational exposed and general population. This study is one of the first to address the occupational exposure to phthalates and DINCH in Europe in e-waste dismantling workers, combining a human biomonitoring approach with analysis of settled indoor dust.

Dibutyl phthalate disrupts energy metabolism and morphology in the gills and induces hepatotoxicity in zebrafish.

This study investigated the acute effects of dibutyl phthalate (DBP) exposure on energy metabolism and gill histology in zebrafish (Danio rerio). The in vitro incubation of gill tissue with 10 μM DBP for 60 min altered tissue energy supply, as shown by decreased lactate content and lactate dehydrogenase (LDH) activity. Higher concentrations of DBP (100 μM and 1 mM) increased lactate content and LDH activity; however, they blocked glucose uptake, depleted the glycogen content in cellular stores, and induced injury to the gills, as measured by LDH release to the extracellular medium. In addition, in vivo exposure of fish to 1 pM DBP for 12 h induced liver damage by increasing alanine aminotransferase (ALT) and gamma-glutamyl transferase (GGT) activities. Gill histology indicated hyperemia, lamellar fusion, lamellar telangiectasis, and necrosis. Data indicate that acute exposure of zebrafish gills to the higher DBP concentrations studied induces anaerobic cellular activity and high lactate production, causing gill damage, diminishing cell viability, and incurring liver dysfunction.

Clastogenic, aneugenic, and tubulin polymerization properties of di-(2-ethylhexyl) phthalate and dibutyl phthalate.

Phthalate compounds were found to disrupt the endocrine system and alter transcriptomes during human embryonic development. In our previous work, we have isolated and reported two such phthalates di-(2-ethylhexyl) phthalate (DEHP) and dibutyl phthalate (DBP) from Brevibacterium mcbrellneri bacteria and evaluated their bioactive properties. Naturally derived phthalates might be less toxic compared with synthesized molecules. We have investigated biologically isolated phthalates to understand the possible genotoxic effects in mice and further investigated in silico binding and polymerization of β-tubulin. Three sub-lethal concentrations of DEHP (150μM, 175μM, and 200μM) and DBP (10μM, 15μM, and 30μM) were studied. The results showed that the phthalates were found to be highly genotoxic in nature. However, the pattern of genotoxic effects was not found to be dose-dependent in the induction of chromosome aberrations (CA), micronuclei (MN), and changes in the mitotic index (MI) in cells. In silico studies of phthalates on polymerization of β-tubulin suggested that both DBP and DEHP were able to interact with the hydrogen bonds and make strong van der Waals interactions with β-tubulin thereby possibly causing destabilization of microtubule network. Our study suggests that these phthalates might be playing an important role in normal cell division thereby showing highly genotoxic effects.

Determination and Traceability Analysis of Phthalic Acid Esters in Garlic (Allium stivum L.) from Jiangsu Province, China

Phthalic acid esters (PAEs) are ubiquitous environmental pollutants and are recognized as a threat to the environment and agricultural product safety across the world. In order to investigate the level of PAEs in garlic, soils, and agricultural films from Pizhou City, Jiangsu province, China, 11 garlic samples, 106 soil samples, and 4 agricultural film samples were collected and analyzed using GC-MS. In addition, the uptake and transport characteristics of six PAEs compounds classified as priority pollutants by the United States Environmental Protection Agency (EPA) in the garlic cultivar Daqingke were investigated under hydroponic conditions. The results indicated that dibutyl phthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP) were the dominant PAEs species in garlic cloves of the different garlic varieties from Pizhou City. The average contents of DBP and DEHP in garlic cloves were 0.611 mg·kg-1 and 0.167 mg·kg-1, respectively, which were significantly higher than those of the commercial varieties of garlic. The concentrations of DBP and DEHP differed in three tissues of garlic bulbs, ordered as the skin of garlic bulb>skin of garlic clove>garlic clove. Dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DIBP), DBP, and DEHP were the main PAEs species and were detected in all the surface soils collected from Pizhou City. Compared with the soil allowable concentrations of the six PAEs in the United States, the DMP and DBP concentrations in approximately 100% and 63.2% of soil samples exceeded the recommended allowable concentrations set by the EPA. However, the levels of DEP, DIBP, and DEHP in the soils were below the maximum allowable concentrations set by the EPA. Nevertheless, the average content of DEHP in soils was 486 μg·kg-1 and was found to be much higher than that in the other four PAEs. Six PAEs, including DMP, DEP, DIBP, DBP, butyl benzyl phthalate (BBP), and DEHP, were detected in all the agricultural film samples. Among them, the contents of DBP and DEHP in the agricultural films were the highest, accounting for 53.7%-63.2% of the total PAEs. The amount of PAEs present in the residual film was significantly lower than that in the new film, and all six PAEs were detected in garlic or soil samples, suggesting that agricultural film can be an important source of PAEs in garlic farming soils and garlic. Furthermore, the garlic plants absorbed DMP and DEP efficiently from the substrate and showed higher translocation factors (TFs) for DMP and DEP than those for DBP, BBP, DEHP, and di-n-octyl phthalate (DnOP), resulting in a higher accumulation of DMP and DEP in the over-ground parts of garlic. In contrast, DBP and BBP in roots of garlic displayed higher bioconcentration factors (57.4 and 81.5, respectively) compared to those of the other four PAEs, whereas the TFs of DBP and BBP were lower; this may have contributed to the high accumulation of DBP in garlic bulbs. The BCFs and TFs of DEHP and DnOP in garlic were relatively lower, but the DEHP had been detected in all garlic cloves, which may be a result of the higher DEHP contents in soils.

Survey on Phthalates in Beer Packaged in Aluminum Cans, PET and Glass Bottles

Phthalates are known as endocrine disruptors and are common in plastic polymers, varnishes, and printing inks. However, they most often enter the human body through food. Plastic materials that hold food contain different chemicals, and phthalates are one of them. Phthalates can also be found in microplastics since microplastic particles serve as a vector for different chemicals that can be slowly released into food and beverages. The aim of this preliminary study was to determine the concentration and types of phthalates (dimethyl phthalate, diethyl phthalate, diisobutyl phthalate, dibutyl phthalate, bis (2-ethylhexyl) phthalate, di-n-octyl-phthalate) in beer packaged in aluminum cans, PET, and glass bottles. Ten aluminum-canned beers, sixteen PET-packaged, and eighteen glass-bottled beers were bought at a local food store and subjected to GC–MS analysis to quantify and qualify phthalates. The results indicate that PET-packaged beers can contain significant amounts of phthalates; in sample P10, the total sum of phthalates reached 219.82 µg/L. Especially high concentrations of dibutyl phthalate were found in all samples, but the highest concentration was detected in sample P13 at 92.17 µg/L. However, canned beers showed even higher levels of certain phthalates, such as bis (2-ethylhexyl) phthalate, which amounted to 326.81 µg/L in sample C1. In short, phthalates pose a serious health-concerning problem and should be regarded as such.

The role of small GTPases in bisphenol AF-induced multinucleation in comparison with dibutyl phthalate in the male germ cells.

The goal of this study is to examine bisphenol AF (BPAF)-induced multinucleation (MNC) in comparison with dibutyl phthalate (DBP), known to induce MNC in mouse gonocytes in vivo. We performed image-based single-cell high content analysis (HCA) in the mouse spermatogonia C18-4 cells treated with various concentrations of BPAF and DBP. BPAF as low as 5 µM was cytotoxic and resulted in 40% cell death of the C18-4 cells after 72 h. HCA revealed that 5 µM of BPAF significantly increased the number of MNC by an average of 3.6-fold. DBP did not induce MNC in the doses we tested. Cytokinesis is tightly regulated by various small GTPase-signaling pathways. We, therefore, tested 5 selective GTPase inhibitors and found that Y27632, a ROCK inhibitor, reduced the BPAF-induced MNC by nearly 30%. Inhibition of Cdc42 by ML141 conversely increased the number of BPAF-induced MNC. We performed a hierarchical cluster analysis of the HCA data and demonstrated that the cytoskeletal disruption by BPAF was reversely modified by Y27632. We found that mRNA expression of genes regulating Rho and Rac GTPase activities, p190RhoGap and MgcRacGap, was altered in BPAF-treated C18-4 cells in a time-dependent manner. Multinucleated gonocytes are often indicators of disease pathologies. Our results provided the first evidence of mechanisms of the dual toxicity by BPAF to male germ cells, which induces chromosome endoreplication without the coordinated cytokinetic cellular components. The unique genotoxic mechanism of forming multinucleated germ cells suggests a novel mode of action in the male repro-toxicity concern over the increasingly ubiquitous presence of BPA analogs.

The Effect of Dibutyl Phthalate (DBP) on Soybean Seed Germination

Industrial plasticizer phthalate esters (PAEs) is commonly utilized in PVC products. One of the most widespread plastic additives, dibutyl phthalate (DBP), is a known endocrine disruptor in the environment. The high volatility and low durability of DBP mean that it is present in soil, water, and air and can be taken up by the roots of plants, where it may stunt their development. Soybean seeds were used in a series of experiments in which the effects of DBP on germination were measured at doses of 0, 0.1, 0.5, 1.0, 5.0, and 10.0 mg/L. Soluble sugar content, superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), isocitrate lyase (ICL), and malate dehydrogenase (MDH) levels were evaluated on days 1, 3, 5, and 7. The results demonstrated that the concentration and duration of DBP treatment both contribute to the observable effect on soybean seeds. Soybean germination, antioxidant enzyme activity, and glyoxylate cycling enzyme activity were all stimulated by DBP at concentrations below 1 mg/L, and the stimulatory impact was negatively linked with increasing DBP concentration. Soybean seed germination, antioxidant enzyme activity, and glyoxylate cycling enzyme were all suppressed at concentrations of DBP >1mg/L. Inhibitory action was improved with an elevation of DBP concentration.

Dibutyl phthalate promotes angiogenesis in EA.hy926 cells through estrogen receptor-dependent activation of ERK1/2, PI3K-Akt, and NO signaling pathways

Dibutyl phthalate (DBP) is an endocrine disruptor that has been widely used in various products of human use. DBP exposure has been associated with reproductive and cardiovascular diseases and metabolic disorders. Although dysfunction of the vascular endothelium is responsible for many cardiovascular and metabolic diseases, little is known about the effects of DBP on human endothelium. In this study, we investigated the effect of three concentrations of DBP (10−6, 10−5, and 10−4 M) on angiogenesis in human endothelial cell (EC) line EA.hy926 after acute exposure. Tube formation assay was used to investigate in vitro angiogenesis, whereas qRT-PCR was employed to measure mRNA expression. The effect of DBP on extracellular signal-regulated kinase 1/2 (ERK1/2), phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt), and endothelial nitric oxide (NO) synthase (eNOS) activation was examined using Western blotting, whereas the Griess method was used to assess NO production. Results show that the 24-h-long exposure to 10−4 M DBP increased endothelial tube formation, which was prevented by addition of U0126 (ERK1/2 inhibitor), wortmannin (PI3K-Akt inhibitor), and l-NAME (NOS inhibitor). Short exposure to 10−4 M DBP (from 15 to 120 min) phosphorylated ERK1/2, Akt, and eNOS in different time points and increased NO production after 24 and 48 h of exposure. Application of nuclear estrogen receptor (ER) and G protein-coupled ER (GPER) inhibitors ICI 182,780 and G-15, respectively, abolished the DBP-mediated ERK1/2, Akt, and eNOS phosphorylation and increase in NO production. In this study, we report for the first time that DBP exerts a pro-angiogenic effect on human vascular ECs and describe the molecular mechanism involving ER- and GPER-dependent activation of ERK1/2, PI3K-Akt, and NO signaling pathways.

A preliminary cumulative risk assessment of Diethylhexyl phthalate and Dibutyl phthalate based on the inhibition of embryonic development via the PPARγ pathway

BackgroundDiethylhexyl phthalate (DEHP) and dibutyl phthalate (DBP) are the two most widely used plasticizers (PAEs) that may act as endocrine disruptors and cause developmental toxicity. MethodsWe measured intrauterine exposure to DEHP and DBP which are the two most widely used phthalates (PAEs) in the cord blood of 50 postpartum women using ultra-HPLC-tandem mass spectrometry and solid-phase extraction. The embryotoxicity of DEHP and DBP was evaluated using the human embryonic stem cell test (hEST). Based on the intrauterine exposure concentration of DEHP and DBP in pregnant women and the reference point of toxic effects in hEST, we used the reference point index (RPI) method to assess the cumulative risk of DBP and DEHP. ResultsThe mean concentrations of DEHP and DBP were 99.9 μg/L and 24.7 μg/L, respectively. DEHP and DBP were weakly embryotoxic, and the benchmark dose lower confidence intervals were 29.99 and 0.99 μg/mL, respectively, as determined using hEST. Both DEHP and DBP inhibited embryonic development via PPAR/PTEN/Akt signal pathway. ConclusionThe findings suggest that the cumulative risk in pregnant women with a high level of exposure should receive more attention in the future.

Assessment of Cytotoxic, Genotoxic, and Oxidative Stress of Dibutyl Phthalate on Cultured Bovine Peripheral Lymphocytes.

Recently, there have been numerous reports showing that phthalates have negative human health impacts and may cause several diseases such as asthma, breast cancer, obesity, type II diabetes, and male infertility. Animals are also exposed to phthalates through the environment and can cause adverse health effects on them. Several studies have been found on the cytogenetic effects of dibutyl phthalate (DBP) on different organisms but no documented evidence has been found on the cytotoxic and genotoxic effects of dibutyl phthalate (DBP) on bovine cultured lymphocytes. MTT assay was performed on different series of DBP concentrations (10 μM, 20 μM, 30 μM, 50 μM, 70 μM, 100 μM). A concentration-dependent decrease in cell viability was observed by the DBP. The LD50, LD50/2, and 2∗LD50 were found to be 50 μM, 30 μM, and 80 μM on bovine lymphocytes, respectively. Then, these concentrations of DBP were utilized to perform comet, micronucleus assays, and oxidative stress. A concentration-dependent increase in DNA damage, oxidative stress, and micronuclei formation was observed in lymphocytes by the DBP as compared to the control group. Highest genotoxic effects were observed at a concentration of 2∗LD50. Similarly, total oxidative stress was found higher, and antioxidative stress was lower in concentration-dependent manner by the DBP. The current study revealed a significant cytotoxic, genotoxic, and oxidative stress of DBP on cultured bovine lymphocytes.

Comparison of Different Chemical Extraction Methods for Predicting the Bioavailability and Phytotoxicity of Soil PAEs to Green Vegetables (Brassica Rapa Var. Chinensis).

The aim of the present study was to compare the predictive ability of four chemical extraction methods, i.e., Tenax, hydroxypropyl[β]cyclodextrin (HPCD), n-butanol and low-molecular-weight-organic-acids (LMWOA), for predicting the bioavailability and phytotoxicity of soil phthalic acid esters to the green vegetable Shanghaiqing (SHQ). Results showed that the extraction ability of different extraction methods varies significantly. For dibutyl phthalate (DBP), the extraction ability followed the order of Tenax > LMWOA > HPCD > n-butanol. For di-(2-ethylhexyl) phthalate (DEHP), the order of the extraction ability was n-butanol > HPCD > Tenax > LMWOA. All the extraction methods underestimated the DBP concentration while overestimating the DEHP concentration accumulated by SHQ. The concentrations of DBP and DEHP extracted by Tenax were most related to the concentrations accumulated by SHQ and the phytotoxicity indicators of SHQ. Tenax can serve as a good chemical extractant to assess the bioavailability and phytotoxicity of soil DBP and DEHP to SHQ.

Association of childhood rhinitis with phthalate acid esters in household dust in Shanghai residences.

Phthalate acid esters (PAEs) have been identified to be associated with children's health. Present study was conducted to assess associations between PAEs in household dust and childhood rhinitis. Based on phase II of CCHH study (China, Children, Home, Health) conducted in Shanghai, China, 266 indoor dust samples were collected from participants' families. Concentrations of PAEs in dust samples were measured by chemical treatment and gas chromatograph-mass spectrometer. Information about individuals and residences was surveyed by questionnaires. Logistic regression models were applied to obtain the associations between PAEs and childhood rhinitis. Higher concentrations of benzyl butyl phthalate (BBP) were found in those families with children who had diagnosed rhinitis. Significantly higher concentrations of bis(2-ethylhexyl) phthalate (DEHP) and PAEs with high molecular weight (HMW-PAEs) were found in the positive group of lifetime rhinitis. Using the multiple and ordinal logistic regression models adjusted by covariates, dibutyl phthalate (DBP), DEHP, and HMW-PAEs were found to be significantly associated with diagnosed rhinitis. Boys who exposure to higher concentrations of DBP, DEHP, HMW-PAEs, and total PAEs have significant associations with diagnosed rhinitis compared with girls who exposure to lower concentration of PAEs. Present observational study indicated that exposure to high concentrations of DBP, DEHP, and HMW-PAEs in house settled dust was a risk factor for rhinitis for children, especially for boys.

Impact of Storage on Levels of Phthalates in Sachet and Bottled Water Brands in Enugu State, Nigeria

ABSTRACT The determination of phthalate ester concentrations in stored packaged water brands produced in Enugu State was carried out and the health risks evaluated. Packaged water samples were obtained in four batches from six sachet water and six bottled water factories, and stored outdoor for 1 month before analysis, while control samples were obtained and analysed immediately after purchase. Solvent extraction was carried out using dichloromethane, and phthalates concentrations were determined using Gas Chromatography-Mass Spectrometry. The range of limit of detection, recovery analysis and limit of quantitation were 0.001-0.002 mg/L, 81.26–91.47% and 0.003-0.006 mg/L respectively. The concentrations (µg/L) of DMP, BBP, MEHP, DBP and PADHE were<0.002–0.13, 0.41–1.84, <0.002–19.66, 0.76–4.22 and <0.002–0.81 in the bottled water and 0.11–0.36, <0.002–0.43, 0.21–5.75, 0.87–3.28 and <0.002–0.57 in the sachet water. Dimethyl phthalate (DMP) concentrations in the exposed and stored sachet water were significantly higher (P˂0.05) than that obtained from bottled water. There were also significantly higher (P<0.05) concentrations of Diethyl phthalate (DEP), Butyl benzyl phthalate (BBP), Di-butyl phthalate (DBP) and phthalic acid decyl hept-2-yl ester (PADHE), and pH in exposed sachet water than the control. Non-carcinogenic hazard quotient for phthalate esters in the packaged water samples was ˂1, which indicates no carcinogenic health risk. The contribution of individual phthalates to drinking water for Mono-2-ethylhexyl phthalate in both adults and toddlers exceeded the 0.5% TDI in some of the packaged water brands. Results suggest that increased concentrations of phthalate esters in the exposed packaged water samples were as a result of storage temperature, while the presence of phthalate esters in few of the control samples was probably from the packaging process. Although the levels of phthalates were low, regular consumption of packaged water could be detrimental to health of the general populace.

Integration of data from the in vitro long-term exposure study on human endothelial cells and the in silico analysis: A case of dibutyl phthalate-induced vascular dysfunction

General population is exposed to dibutyl phthalate (DBP) through continuous use of various consumer products. DBP exhibits its effects mainly on the endocrine and reproductive system but it can also affect the function of the vasculature; however, the underlying mechanisms behind DBP-induced vascular dysfunction are not fully understood. To infer pathways, molecular functions, biological processes, and human diseases associated with DBP exposure, we integrated the toxicogenomic data obtained from the 4-week-long exposure of human vascular endothelial cells (ECs) to three environmentally relevant concentrations of DBP with the in silico analysis. Nine genes were affected by DBP exposure: six of the integrin family, VCAM1, ICAM1, and MMP2. As shown by the in silico analysis, changes in DBP-affected genes could affect extracellular matrix and binding of molecules and cells to ECs, thereby altering cell adhesion and migration. Several pathways, molecular functions, and biological processes were further identified to provide insight into the DBP-vascular disease relationships and the potential mechanism of action. The top three human disease categories associated with DBP exposure and vascular dysfunction include cardiovascular, cerebrovascular, and immune system diseases. Integration of experimental and in silico approaches may offer better understanding of the potential human health risks associated with DBP exposure.

Di-butyl phthalate (DBP) induces defects during embryonic eye development in zebrafish.

Di-butyl phthalate (DBP) is a phthalate ester (PAEs) added during the manufacturing of plastics to make them stronger, yet more pliable. DBP is noncovalently bound to plastics resulting in leaching into the environment. Concerning concentrations of DBP have been noted in surface and groundwater, aquatic ecosystems, soil and atmospheric environments globally. Global production of phthalates and thus concomitant exposure has increased over the years making studies on the ecological and environmental safety needed. Most of the literature on DBP focuses on the endocrine disrupting properties of phthalate esters, but the developmental toxicity of DBP is an understudied area. Here, we treat gastrula staged zebrafish embryos with environmentally relevant concentrations of DBP (2.5 µM). We find defects in eye development at 96 h post fertilization including a decrease in the size of the lens and retina in DBP-treated embryos. Defects in eye vascularization as well as loss of the optic nerve and optic tectum were also noted. Here we conclude that exposure to environmentally relevant doses of DBP during early embryonic development is toxic to eye development.