Occurrence Of Phthalate Esters Research Articles

Assessment of Health Risks Associated with the Presence of Phthalate Esters in Tea Samples: A Comprehensive Analysis

This study presents novel insights into the occurrence of phthalate esters (PAEs) in tea samples consumed in Turkey. Employing multiple reaction monitoring (MRM) mode with precursor-product ion transitions, quantitative and qualitative analyses of PAEs were conducted using an LC-MS/MS system. A dispersive solid-phase extraction (dSPE) technique was utilized to determine the PAE contents in the tea samples. The limit of detection for all PAEs ranged from 0.350 to 1.882 ng/mL, while the limit of quantification ranged from 1.165 to 6.273 ng/mL. Moreover, strong correlations were observed with R2 values exceeding 0.996 for all PAEs, indicating robustness. Recovery studies demonstrated satisfactory results, falling within the range of 92.20% to 97.24%, indicating effective retrieval. The relative standard deviation values for the target PAEs ranged from 3.22% to 5.54%. The study findings indicate that PAE levels in the tea samples generally comply with permissible limits set by EU regulations, except for DBP (1807.70±1478.86 ng/mL). Notably, DBP and DINP (941.44±852.80 ng/mL) were identified as the predominant plasticizers in the tea samples. Health risk assessment, conducted through hazard quotient and hazard index calculations across various age groups, consistently yielded values below 1 for DEP, DEHP, DINP, BBP, and DBP, suggesting minimal non-carcinogenic health risks associated with tea consumption across all age groups. Furthermore, the intake of individual phthalate esters, including DEP, DEHP, DINP, BBP, and DBP, remained below acceptable daily limits defined by the EFSA. Although some tea products exhibited slightly elevated PAE levels, overall, the study emphasizes the importance of continuous monitoring and regulations to ensure the safety of packaged tea and mitigate potential long-term exposure risks linked to PAEs.

Occurrence of phthalate esters in the yellow and Yangtze rivers of china: Risk assessment and source apportionment

Phthalate esters (PAEs), recognized as endocrine disruptors, are released into the environment during usage, thereby exerting adverse ecological effects. This study investigates the occurrence, sources, and risk assessment of PAEs in surface water obtained from 36 sampling points within the Yellow River and Yangtze River basins. The total concentration of PAEs in the Yellow River spans from 124.5 to 836.5 ng/L, with Dimethyl phthalate (DMP) (75.4 ± 102.7 ng/L) and Diisobutyl phthalate (DiBP) (263.4 ± 103.1 ng/L) emerging as the predominant types. Concentrations exhibit a pattern of upstream (512.9 ± 202.1 ng/L) > midstream (344.5 ± 135.3 ng/L) > downstream (177.8 ± 46.7 ng/L). In the Yangtze River, the total concentration ranges from 81.9 to 441.6 ng/L, with DMP (46.1 ± 23.4 ng/L), Diethyl phthalate (DEP) (93.3 ± 45.2 ng/L), and DiBP (174.2 ± 67.6 ng/L) as the primary components. Concentration levels follow a midstream (324.8 ± 107.3 ng/L) > upstream (200.8 ± 51.8 ng/L) > downstream (165.8 ± 71.6 ng/L) pattern. Attention should be directed towards the moderate ecological risks of DiBP in the upstream of HH, and both the upstream and midstream of CJ need consideration for the moderate ecological risks associated with Di-n-octyl phthalate (DNOP). Conversely, in other regions, the associated risk with PAEs is either low or negligible. The main source of PAEs in Yellow River is attributed to the release of construction land, while in the Yangtze River Basin, it stems from the accumulation of pollutants in lakes and forests discharged into the river. These findings are instrumental for pinpointing sources of PAEs pollution and formulating control strategies in the Yellow and Yangtze Rivers, providing valuable insights for global PAEs research in other major rivers.

Influence of leachate microenvironment on the occurrence of phthalate esters in landfills

Phthalate esters (PAEs) are added to various products as plasticizers. Plastic waste containing PAEs enters landfills as they age with use. However, the influence of microenvironmental changes on the occurrence of PAEs during landfill stabilization is still unknown. In this study, we evaluated the relationship between the physical and chemical properties of leachate, the structure of bacterial communities and the chemical structure of dissolved organic matter (DOM), and the occurrence of PAEs and the mechanism underlying their responses to changes. Landfill leachate in different stabilization states had high Cl− and NH4+ contents and its metal element (Cr, Pb, and Zn) contents generally decreased with the increase in landfill ages. Proteobacteria, Bacteroidetes, and Firmicutes were important phyla and had an average relative abundance of 68.63%. The lignin/carboxylate-rich alicyclic molecule structure was the main component of DOM (56%–64%). Of the 6-priority controlled PAEs in leachate, di-n-butyl phthalate was the most abundant (1046 μg L−1), while butyl phthalate was not detected. The results showed that pH, the relative abundance of Chloroflexi, and the value of SUVA254 can directly influence the occurrence of PAEs in leachate. The positive and negative effects vary depending on the PAE content and molecular weight. DBP and DEHP have higher environmental risks in the aquatic system. These results are intended to provide a scientific basis for the evolutionary characterization of the microenvironment in complex environmental systems and the control of novel contaminants, such as PAEs.

Occurrence, Fate, and Reduction Measures of Phthalates in the Cooking Process: A Review.

Phthalate esters (PAEs), which are commonly used as plasticizers in food processing and packaging, are common pollutants. Dietary intake is the primary route to human exposure to PAEs. Data show that retail packaged and cooked foods are most likely to be contaminated with PAEs, indicating that the food preparation and cooking processes may contribute to the migration and transformation of PAEs in food. In this review, we collected the latest investigations on the occurrence of PAEs in different food categories, discussed the mechanisms of the fate of PAEs during cooking, and summarized the reduction measures of PAEs in food. Foods such as water and beverages, meat, condiments, and baby foods are linked to PAE exposure. Many cooking techniques and procedures, including steaming, boiling, microwave heating, toasting, frying, and packaging, are responsible for the occurrence, migration, and transformation of PAEs in foods. The occurrence, transformation, and migration of PAEs in food are influenced by a variety of factors, including food categories, the cooking process, packaging materials, and physicochemical properties of PAEs. There are several ways to prevent or reduce PAEs in food, including the selection of safe packaging materials, proper food categories, cooking methods, and replacement of PAEs.

Occurrence of Phthalate Esters in Coffee and Risk Assessment.

Coffee, one of the most widely consumed beverages in the world, is commercialized as powder and beans in different types of packaging and extracted through several methods. In this regard, the present study focused on evaluating the concentration of two of the most used phthalates in plastic materials (bis(2-ethylhexyl)phthalate (DEHP) and di-butyl phthalate (DBP)) in coffee powder and beverages to assess their migration from different packaging and machines. Furthermore, the levels of exposure to these endocrine disruptors in regular coffee consumers were estimated. Samples of packaged coffee powder/beans (n = 60) from different forms of packaging (multilayer bag, aluminum tin, and paper pod) and coffee beverages (n = 40) that were differently extracted (by professional espresso machine (PEM), Moka pot (MP), and home espresso machine (HEM)) were analyzed by extraction of the lipid fraction, purification, and determination by gas chromatography-mass spectrometry (GC/MS). Risk due to consumption of coffee (1-6 cups) was assessed based on tolerable daily intake (TDI) and incremental lifetime cancer risk (ILCR). No significant differences emerged in DBP and DEHP concentrations among different types of packaging (multilayer, aluminum, and paper), whereas higher levels of DEHP were reported in beverages extracted by PEM (6.65, 2.58-11.32) than by MP (0.78, 0.59-0.91) and HEM (0.83, 0.62-0.98). The presence of higher DEHP levels in coffee beverages than in coffee powder may be due to its leaching through machine components. However, the levels of PAEs did not exceed the specific migration limits (SMLs) set out for food contact materials (FCM), and exposure to PAEs from coffee beverages was low, justifying the small risk due of its consumption. Consequently, coffee can be considered a safe beverage for exposure to some phthalic acid esters (PAEs).

The occurrence, fate, toxicity, and biodegradation of phthalate esters: An overview.

Phthalate esters (PAEs) are a class of emerging xenobiotic compounds that are extensively used as plasticizers. In recent times, there has been an increasing concern over the risk of this pervasive pollution exposure causing endocrine disruption and carcinogenicity in humans and animals. The widespread use of PAEs in home and industrial applications has resulted in their discharge in aquatic bodies via leaching, volatilization, and precipitation. In this overview, the current state of PAE pollution, its potential origins, its fate, as well as its effects on the aquatic environment are discussed. A state-of-the-art review of several studies in the literature that focus on the biological degradation of PAEs is included in this study. The paper aims to provide a comprehensive view of current research on PAEs in the environment, highlighting its fate and alleviated risks on the aquatic biotas, their challenges, future prospects, and the need for good management and policies for its remediation. PRACTITIONER POINTS: Occurrence of phthalate esters was summarized in various environmental matrices along with its serious ecotoxicological implications on biota. Wastewater is the prime source of PAEs contamination. Lack of species-specific effects on biota due to dose, exposure route, and susceptibility. The predominant route to mineralization in PAEs is biodegradation. A critical analysis of worldwide PAE production and consumption identifies the necessity for global PAE production, consumption, and release policies.

Occurrence of phthalate esters and preliminary data on microplastics in fish from the Tyrrhenian sea (Italy) and impact on human health

Phthalic acid esters (PAEs) are chemical pollutants widely distributed in the marine environment. They can accumulate in biota, posing a risk to the marine ecosystem and humans. The aim of this study was to measure the content of PAEs in the gills and muscles of three fish species (Mugil cephalus, Diplodus annularis, and Mullus barbatus) caught along the coast of Campania (Italy), as well as to ascertain the dietary exposure to PAEs through the consumption of fish. Secondly, a preliminary insight into microplastics (MPs) pollution in this area was provided through the analysis of Mugil cephalus organs. Solid-phase extraction (SPE) and gas chromatography-mass spectrometry (GC-MS) were used for the PAEs analysis, while an Fourier-transform infrared (FTIR) microscope was used to detect MPs after a pre-digestion of the samples. Risk assessment was based on estimated daily intake (EDI) and lifetime cancer risk (LTCR). The results showed higher bioaccumulation of PAEs in Mullus barbatus than in the other two species and higher concentration in gills than in muscles. MPs (polyamide, polypropylene, and high-density polyethylene) were detected in half of the gill samples, but no particle was detected in the muscle samples of Mugil cephalus. A low carcinogenic and non-carcinogenic risk from the consumption of fish emerged, although a potential risk for the development of cancer was found in the worst-case, especially in toddlers. In conclusion, this study provides insight into PAEs pollution in the Tyrrhenian Sea (Italy), their distribution in fish with different behaviors, and the potential risk to the consumer. Moreover, the data on pollution by MPs in this area could form the basis for future studies.

Source tracing and health risk assessment of phthalate esters in household tap-water: A case study of the urban area of Quanzhou, Southeast China

The occurrence of phthalate esters (PAEs) in household tap water has been investigated via the presence of their geochemical characteristics in the pretreatment and transfer processes of water plants in the urban and suburban areas of the subtropical medium-sized city of Quanzhou, southeast China. The results for all approximately 300 tap water samples collected from 6 sampling stations at household kitchens from Nov. 30, 2017, to Dec. 6, 2018, showed that dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutylphthaate (DIBP), di-n-butyl phthalate (DBP), and di(2-ethylhexyl) phthalate (DEHP) could be identified and quantified among the 16 PAE congeners with the developed gas chromatographymass spectrometry method. The levels of the sum of 5 PAE congeners (Σ5PAEs) for all tap water ranged from 780.0 ng/L to 9180 ng/L, while DIBP and DEHP were the most abundant congeners, accounting for 82.2% in the dry season, 89.9% in the normal season, and 89.3% in the wet season. Factors of the transferring process, such as the spatial distance from the sampling station to the water plant, the material of pipelines, and the storage time of tap water in the pipeline, affected the levels of PAE congeners in tap water from the correlation of Σ5PAEs levels and transferring distance according to hierarchical cluster analysis. The seasonal variations in Σ5PAEs and each congener had good agreement with the temperature, suggesting that PAEs in tap water mainly come from raw water, which should be further explored in future work. Health risk assessment of PAEs in tap water with the HQ method showed that the occurrence of DEP and DBP has no noncarcinogenic risk for adults and children, while the concentration of DEHP might cause potential noncarcinogenic risk for adults and children, which should be given considerably more attention.

Occurrence and dietary exposure risk assessment of phthalate esters in Chinese mitten crabs (Eriocheir sinensis) from Hubei, central China

ABSTRACT: Recently, the wide existence of phthalate esters (PAEs) in aquatic environment has drawn great public attention, due to their negative health impacts on human and aquatic organisms. Chinese mitten crab is a major aquaculture economic resource in Hubei, feeding a world population of more than 10 million. Due to their wide consumption and great economic value, it's imperative to study the dietary risks of PAEs in mitten crabs ensuring food safety. In this study, a simple and selective method based on matrix matched calibration strategy coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS) was developed to quantify 17 PAEs in Chinese mitten crabs (Eriocheir sinensis) from Hubei, central China and their dietary exposure risks were investigated. Recoveries were in the range of 56.9–131.2%. The limits of detection and quantification were 0.01–0.2 μg kg−1 and 0.5–7.5 μg kg−1, respectively. The PAEs were found to be present in both juvenile and adult mitten crabs in the study area. The mean concentration of total PAEs (∑17 PAEs) was 495.73–2033.39 μg kg−1 in crab muscles, and 159.69–651.69 μg kg−1 in hepatopancreas and gonad, respectively. The highest detection frequency of PAEs in all samples was di(2-ethylhexyl) phthalate (DEHP), and followed by dibutyl phthalate (DBP) and diisobutyl phthalate (DiBP). The estimated daily intakes of DEHP, DBP and DiBP, were more than ten times greater than any other PAEs. Calculated hazard ratio of PAEs were all below 0.1, suggesting that intake of PAEs by dietary of mitten crabs had non-cancer risk for both adults and children. Overall, this study provides a reliable method to evaluate PAEs pollution in aquatic food and critical data on the occurrence of PAEs in Chinese mitten crabs (Eriocheir sinensis) from Hubei, central China, which is a key part of PAEs pollution prevention in food source.

Occurrence and removal characteristics of phthalate esters from bottled drinking water using silver modified roasted date pits

BackgroundThis paper aims to investigate the occurrence and removal characteristics of phthalate esters from bottled drinking water using silver modified roasted date pits. Three adsorbents, namely roasted date pits (RODP), silver-modified roasted date pits (S-RODP), and activated carbon (AC) were used to investigate their adsorption characterizations in removing dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), butyl benzyl phthalate (BBP), di-2-ethylhexyl phthalate (DEHP), and di-n-octyl phthalate (DNOP) from the collected bottle water samples.MethodsThe occurrences of the phthalate esters in the collected bottled water samples were carried out at different temperatures (30, 50, and 60 °C), and analyzed using gas chromatography-mass spectrometry analysis - selected ion monitoring. Batch adsorption isotherms were used to study and establish the efficiency of such adsorbents in removing phthalate esters, in which they describe the adsorbent-adsorbate interaction systems. Adsorption efficiency of the various adsorbents was investigated by using different adsorbent masses (0.05 g, 0.10 g, and 0.15 g) and temperature (30 °C, 50 °C, and 60 °C). Different physical and chemical characterizations were studied using scanning electron microscopy (SEM), Fourier transform infrared (FTIR), Brunauer-Emmett-Teller (BET) surface area, pore radius, and pore volume.ResultsThe results indicated that the most abundant phthalate esters were DMP followed by DEP under 30 °C; however, DNOP was not detected in any of the tested water samples, except for one sample under 30 °C with a concentration of 0.031 μg/mL. The obtained results showed that phthalate esters leaching to the bottled drinking water were affected by storage temperature. The phthalate esters levels were increased with increasing the temperature to 60 °C. It was concluded that the ability of S-RODP for the adsorption of phthalate esters was better than the removal percentage obtained by AC and RODP. The removal percentage was increased from 90 to 99% by increasing the temperature from 30 to 50 °C and then decreased to 92.3% at 60 °C.ConclusionRODP was successfully used as an effective adsorbent for phthalate esters removal from drinking water. However, S-RODP has the highest removal abilities than other adsorbents due to the newly formed functional groups on its surface.

Occurrence, Ecological and Health Risk Assessment of Phthalate Esters in Surface Water of U-Tapao Canal, Southern, Thailand.

Phthalate esters (PAEs) are well known for their environmental contamination and endocrine-disrupting effects on wildlife and humans. In this study, the occurrence of PAEs and ecotoxicological risk assessments were performed in one of the significant canals in southern Thailand, named U-Tapao. Water samples were collected and analyzed for the six most common PAEs by using a gas chromatograph-mass spectrometer (GC-MS). Of the 6 PAEs analyzed, only three PAEs, including di-n-butyl phthalate (DBP), di (2-Ethylhexyl) phthalate (DEHP), and diisononyl phthalate (DiNP) were detected in water samples. The total concentration of PAEs ranged from 1.44 to 12.08 µg/L, with a mean level of 4.76 µg/L. The total average concentration of PAEs found in the canal was higher than the criteria of 3 µg/L for PAEs recommended for the protection of fish and other aquatic organisms by the United States Environmental Protection Agency (USEPA). The results of the potential ecological risk assessment of the risk quotient (RQ) method revealed that DEHP and DiNP posed a high risk to algae and crustacean and crustacean and fish, respectively, whereas DBP posed a medium risk to the different aquatic species. However, current levels of noncarcinogenic and carcinogenic risks via ingestion and dermal exposure in children and adults are within acceptable limits. The baseline data of PAEs in this canal will be beneficial to the strategic and future pollutant control along the canal network.

Occurrence of phthalate esters and microplastics in urban secondary effluents, receiving water bodies and reclaimed water treatment processes

The occurrence of phthalate esters (PAEs) and microplastics (MPs) was simultaneously investigated in four wastewater treatment plants (WWTPs), receiving water bodies and reclaimed water treatment processes (RWTPs) in winter and spring. Four PAEs (dimethyl phthalate, dibutyl phthalate, diisobutyl phthalate, and di(2-ethylhexyl)phthalate) were detected. The total concentrations of PAEs were 568.9–1847.5 ng/L in the four WWTP effluents and 39.9–1847.5 ng/L in the four receiving water bodies. Di(2-ethylhexyl)phthalate had the highest concentration among the PAEs. MPs were mostly in the form of granules and fragments with size <0.01 mm in the four WWTP effluents (276–1030 items/L) and receiving water bodies (103–4458 items/L). The four WWTP effluents were important sources of PAEs to the receiving water bodies in spring but were not likely to be the sources of MPs. The overall removal rates of PAEs and MPs were 47.7%–81.6% and 63.5%–95.4% in the four RWTPs. Low or negative removal rates of PAEs were observed in chlorination and ozonation. Clarification, filtration (except ultrafiltration) and reverse osmosis were the dominant processes, contributing 42.7%–69.2%, 25.3%–59.3%, and 22.6%–51.0%, respectively, of the MP removal in the RWTPs. According to the Spearman analysis results, the levels of PAEs and MPs had more significant correlations with the physicochemical parameters of water samples from the RWTPs (including the WWTP effluents) than those of the receiving water bodies. The results indicated that the levels of PAEs and MPs in surface waters could be significantly influenced by the surrounding environment.

Occurrence of phthalate esters in the eastern coast of Thailand.

In this work, we investigated possible contamination of phthalates in seawater and sediment around the eastern coast of Thailand in the area of Chonburi, Rayong, and Chanthaburi. The main focus was on Pradu Bay east of Map Ta Phut, a well-known industrial and economic hub in Thailand. Among six selected phthalates of interest, diethyl phthalate (DEP), and benzyl butyl phthalate (BBP) were not found in any sample, while the concentrations of dimethyl phthalate (DMP) and dioctyl phthalate (DnOP) were very low or undetectable in most samples. In December 2014, the concentration of dibutyl phthalate (DBP) and diethylhexyl phthalate (DEHP) in Pradu Bay were 0.23-0.77 and 0.31-0.91 μg L-1 in seawater, respectively and non-detected (ND)-0.80 and ND-1.65 μg g-1 for 11 out of 20 sediment samples. DBP and DEHP were considered as the predominant congeners. A surface mapping system provided us an overview concentration distribution of DBP and DEHP congeners in seawater and sediment in Pradu Bay, showing a correlation between water and sediment and allowing a prediction of a possible point source. A comparison with the EU standard concentration limit in surface water confirmed that the phthalate concentration in this area was acceptable. However, continuous monitoring of phthalate congeners in the matrices should be done to detect a possible increase in their concentrations. To the best of our knowledge, this is the first study to determine concentrations of phthalates in seawater and sediment along the east coast of Thailand.

The occurrence, composition and partitioning of phthalate esters (PAEs) in the water-suspended particulate matter (SPM) system of Lake Chaohu, China

The occurrence, composition, and partitioning of six phthalate esters (PAEs) (dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DIBP), dibutyl phthalate (DBP), butyl benzyl phthalate (BBP) and di(2-ethylhexyl) phthalate (DEHP)) in the water-suspended particulate matter (SPM) system of Lake Chaohu were investigated in this study. Our results showed that PAEs were ubiquitous contaminants in Lake Chaohu. The concentration of the Σ6 PAEs in dissolved and particulate phases ranged from 0.370 to 13.2 μg·L−1 and from 14.4 to 7129 μg·L−1, respectively. The Σ6 PAEs in water and SPM phases exhibited different seasonal trends. PAEs with different degrees of hydrophobicity demonstrated different temporal distributions in the dissolved phase. In particulate phase, all PAEs exhibited the same temporal distribution. Regarding the occurrence of PAEs, significant spatial differences exist between lake and estuary. However, there were no specific differences in PAEs across lake zones and river types of Lake Chaohu. River input should be considered an important source of PAEs in Lake Chaohu. DIBP and DBP were the most abundant PAEs in Lake Chaohu, and DIBP should attract more attention in the future. The organic carbon normalized partitioning coefficient (logKoc) ranged from an average of 2.38 ± 0.86 L·g−1 for BBP to 3.98 ± 0.66 L·g−1 for DEHP, and approximately 2 to 3 unit variations of logKoc existed for the individual PAEs. It was difficult to ascertain whether the partitioning of PAEs was in, near or far from the equilibrium. No linear relationship was found between logKoc and the octanol-water partitioning coefficient (logKow) for PAEs. Koc might not be suitable for describing the partitioning of PAEs in the water-SPM system. The hydrophobicity of PAEs may have little impact on their partitioning in the complex environmental system, and the Kow model may be inappropriate to predict the partitioning of PAEs in natural large lakes.

Occurrence and spatial distribution of phthalate esters in sediments of the Bohai and Yellow seas

Phthalate esters (PEs) are a class of synthetic chemicals that have been widely used as plasticizers in industrial products and households. The occurrence of PEs in the marine environment has been a concern for many years because of their adverse impacts on marine organisms and human health. In this study, six major PEs, i.e. diethyl phthalate (DEP), di‑isobutyl phthalate (DiBP), di‑n‑butyl phthalate (DnBP), benzylbutyl phthalate (BBP), dicyclohexyl phthalate (DCHP) and di‑(2‑ethylhexyl) phthalate (DEHP), were analyzed in sediment samples collected in the Bohai and Yellow seas. The sum concentrations of the six PEs ranged from 1.4 to 24.6 ng/g and the average was 9.1 ng/g. The highest concentrations of PEs in the sediment samples were those of DEHP with a median concentration of 3.77 ng/g, followed by DiBP (median, 1.60 ng/g), DnBP (0.91 ng/g), DEP (0.32 ng/g), BBP (0.03 ng/g) and DCHP (0.01 ng/g). Generally, concentrations of PEs in the Bohai Sea are higher than those in the Yellow Sea. The varying spatial distributions of the individual PEs can be the result of discharge sources, regional ocean circulation patterns, and mud areas in the Bohai and Yellow seas. Significant positive correlations were found between total organic carbon content and the concentrations of DiBP, DnBP, and DEHP. It is estimated that the inventories of the ∑6PEs were 20.73 tons in the Bohai Sea and 65.87 tons in the Yellow Sea. Both riverine discharge and atmospheric deposition are major input sources for the PE sedimentation, while massive plastic litter and microplastics sinking to the ocean floor can directly release PEs into sediment. This study provides an appropriate data set for the assessment of the risk of PEs to the marine ecosystem.

Occurrence of phthalate esters around the major plastic industrial area in southern Taiwan

The increasing usage and disposal of plastic products could cause the wide distribution of phthalate esters (PAEs) in various environmental media. In this study, six PAE compounds, namely dimethyl phthalate, diethyl phthalate, di-n-butyl phthalate, benzyl butyl phthalate, di(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate, were analyzed in various samples collected from the major plastic industrial area of southern Taiwan, including soil, fertilizer and plastic products, for the purposes of identifying of the possible sources of PAEs and assessing the related health risk. The results show that PAEs in soil samples was dominated by DEHP, with the total concentrations in the range of 0.7 ± 0.5, 0.2 ± 0.1, and 0.3 ± 0.2 mg kg−1 for soil samples from farmland, household back gardens and the roadside, respectively. Contents of PAEs in chemical fertilizer (ND—0 0.87 mg kg−1) were higher than that in organic fertilizer (ND—0.08 mg kg−1), and PAEs concentrations (ND—316 mg kg−1) in plastic mulching films were much less than those in the other types of plastic products (ND—1719 mg kg−1), implying that major sources of PAEs in agricultural soil could be the use of chemical fertilizer and plastic products other than plastic mulching films. Health risk assessment suggested that, via the exposure to PAEs in soil, the potential non-cancer and carcinogenic risks for adults and children are minimal in most cases, except that a “moderate” carcinogenic risk for children exposure to DEHP. The results of this study can serve as a reference for further pollution prevention and environmental protection plans in relation to the industrial operation and discharge as well as the farming practices.

Occurrence of phthalate esters in over-the-counter medicines from China and its implications for human exposure

Food, air, personal care products and indoor dust have been recognized as the main routes of exposure to phthalates in Chinese population, but other sources may have been overlooked, e.g., medicines. To fill the knowledge gap, phthalate esters were measured in 96 over-the-counter medicines made in China, including selected 71 Chinese patented medicines and 25 western medicines. It was found that none of the medicines was free of phthalates. The mean concentrations of individual phthalates ranged from 0.001μg/g (dicyclohexyl phthalate) to 5.85μg/g (diethyl phthalate). Among 9 targeted phthalates, di-n-butyl phthalate was the dominant congener, accounting for >65% of the total phthalates in all medicine samples, followed by di-(2-ethylhexyl) phthalate and diethyl phthalate. Phthalates in medicines appeared to derive from gastroresistant film coatings, plastic packing materials or phthalate contaminated rural herbal plants (especially for Chinese patented medicines). Daily human exposure to phthalates was estimated for local patients for one treatment cycle (e.g., one week) based on suggested consumption dosage and phthalate concentrations. Almost all exposure levels were below the guidelines suggested by the United States Environmental Protection Agency or European Food Safety Authority, indicating low health risk with phthalates from consumption of the medicines. In addition, concentration levels of phthalates in patients would increase upon administration but are expected to decrease to the same values as those in patients before they took medicines in several days. Because the number of medicine samples was limited and the concentrations of phthalates varied in a large range, further investigations are needed to acquire more data for better assessment of human health effects for Chinese population.Capsule: Distribution of phthalate esters in over-the-counter medicines and related exposure for Chinese population are examined

Inhibitory mechanism of phthalate esters on Karenia brevis

The occurrence of phthalate esters (PAEs), a class of widely used and environmentally prevalent chemicals, raises concern to environmental and human health globally. The PAEs have been demonstrated to inhibit algae growth, but the underlying mechanisms remain unclear. In this research, diethyl ortho-phthalate (DEP), diallyl phthalate (DAP), di-n-butyl ortho-phthalate (DBP), di-iso-butyl ortho-phthalate, and benzyl-n-butyl ortho-phthalate (BBP) were screened from 11 species of PAEs to study their inhibitory effects on Karenia brevis and determine their target sites on algae. With increasing the alkyl chains of these five PAEs, the values of EC50,96h decreased. The content of malondialdehyde increased with the continuous accumulation of reactive oxygen species (ROS) in the algae cells. Moreover, the superoxide dismutase and catalase contents were first activated and then inhibited. The ultrastructures of Karenia brevis cells were detected by transmission electron microscopy, and cells treated with PAEs exhibiting distorted shapes and large vacuoles. Thus, the algae were damaged by ROS accumulation, resulting in lipid oxidation and algal growth inhibition. The inhibitors of the electron transport chain showed that the sites of ROS production and accumulation in K. brevis cells under DEP and BBP were the mitochondria and chloroplast, respectively. Moreover, the target sites of DAP and DBP were both the chloroplast and mitochondria. These results are useful for controlling PAEs contamination in and revealing the fate of PAEs in aquatic ecosystem.

Occurrence, Species, and Organ Differences in Bioaccumulation Patterns of Phthalate Esters in Municipal Domestic Water Supply Lakes in Ibadan, Nigeria

The occurrence of phthalate esters (PE) was examined in biota, ambient water, and sediments of two man-made lakes (Asejire and Eleyele) in southwestern Nigeria. Five fish species (Tilapia zillii, Hepsetus odoe, Parachanna obscura, Chrysichthys nigrodigitatus, and Mormyrus rume) were analyzed for PE levels and used for calculating bioconcentration factors (BCF) and biota–sediment accumulation factors (BSAF). In addition, measured PE levels were thereafter used to calculate the phthalate pollution index (PPI) in biota and the environment. At both lakes, all sampled species had k-factor > 1, showing apparently normal growth and health condition. Higher PE levels were found in sediments compared with water at both lakes, with a pattern showing that di(2-ethylhexyl) phthalate (DEHP) was predominant PE. While there were no unique patterns of PE concentrations in both lakes, differences were observed in organ concentration patterns that were evident at both lakes. For T. zillii, the BSAF was higher for dibutyl phthalate (DBP) compared to diethyl phthalate (DEP) and lowest for DEHP. The concentration pattern demonstrated that DBP concentrated more in gills (BCF: 6.7), while DEHP concentrated more in liver (BCF: 15.2) of T. zillii at Asejire. At Eleyele, T. zillii liver and gills concentrated less DEP and DEHP. The PPI value was significantly higher in sediment with respective values of 0.27 and 0.44 at Asejire and Eleyele lakes compared with water with respective values of 0.1 and 0.18 at Asejire and Eleyele lakes. Overall, our findings suggest a broader environmental and human health implication of high PE levels in these lakes, since they provide vast water volumes that are used for municipal domestic water supply. Further, these lakes support intense artisanal fisheries, representing significant sources of aquatic food resources for neighboring communities.

Occurrence and Concentration of Phthalate Esters in River Sediment Around Covenant Oxidation Ponds, Covenant University, Ota, Ogun State

Phthalate Esters (PEs) are well known environmental pollutants with wide application as plasticizers in plastic production. Concentrations of 8 PEs were determined in sediment samples collected from upstream and downstream of Covenant University Oxidation Pond (COP) between March and June 2013. Samples were extracted using the mechanical shaking method with double distilled dichloromethane. The prepared extracts were cleaned using activated silica gel-packed column chromatography and analyzed with high capillary gas chromatography equipped with flame ionization detector (GC-FID). The mean concentrations over the study period for the PEs, monoethylphthalate (MMP), dimethylphthalate (DMP), diallylphthalate (DAP), diethylphthalate (DEP), diisobutyl- (DIBP), di-n-butylphthalate (DBP), butyl-benzylphthalate (BBP), and di-(2-ethyl)hexyl phthalate (DEHP) are 23.1 mgkg -1 , 273 mgkg -1 , 28.9 mgkg -1 , 150 mgkg -1 , 26.5 mgkg -1 , 264.5 mgkg -1 , 41.7 mgkg -1 , and 20.9 mgkg -1 for upstream samples. Mean concentrations for the downstream samples are 24.2 mgkg -1 , 280 mgkg -1 , 33.4 mgkg -1 , 176 mg kg -1 , 26.9 mgkg -1 , 264 mgkg -1 , 41.8 mgkg -1 , and 18.2 mgkg -1 , respectively. Generally, the PEs’ concentration in downstream samples was significantly higher ( p >0.05) than upstream except for DIBP, BBP, and DBP whose DEHP concentrations were significantly higher ( p >0.05) upstream than downstream. The distribution pattern of PEs in the sediment is in the order DMP> DBP> DEP> BBP> DAP> DiBP> MMP> DEHP. The occurrence of PEs in the samples analyzed further supports their ubiquity in the environment.