Seasonal distribution and ecological risk of phthalate esters in surface water and marine organisms of the Bohai Sea

Antioxidant defenses and metabolic responses of Mytilus coruscus exposed to various concentrations of PAEs (phthalate esters)

Phthalate esters (PAEs), as a major plasticizer with multi-biotoxicity, are frequently detected in marine environments, and potentially affecting the survival of aquatic organisms. In the study, three typical PAEs (dimethyl phthalate [DMP], dibutyl phthalate [DBP] and di(2-ethylhexyl) phthalate [DEHP]) were selected to investigate the accumulation patterns and ecotoxicological effects on Mytilus coruscus (M. coruscus). In M. coruscus, the accumulation was DEHP>DBP>DMP, and the bioaccumulation in tissues was digestive glands>gills>gonads>muscles. Meanwhile, the activities of superoxide dismutase (SOD) and catalase (CAT) showed an activation-decrease-activation trend of stress, with more pronounced concentration effects. Glutathione reductase (GSH) activity was significantly increased, and its expression was more sensitive to be induced at an early stage. The metabolic profiles of the gonads, digestive glands and muscle tissues were significantly altered, and DEHP had a greater effect on the metabolic profiles of M. coruscus, with the strongest interference. PAEs stress for 7 d significantly altered the volatile components of M. coruscus, with potential implications for their nutritional value. This study provides a biochemical, metabolomic, and nutritional analysis of DMP, DBP, and DEHP toxic effects on M. coruscus from a multidimensional perspective, which provides support for ecotoxicological studies of PAEs on marine organisms. ENVIRONMENTAL IMPLICATION: Phthalate esters (PAEs), synthetic compounds from phthalic acid, are widespread in the environment, household products, aquatic plants, animals, and crops, posing a significant threat to human health. However, the majority of toxicological studies examining the effects of PAEs on aquatic organisms primarily focus on non-economic model organisms like algae and zebrafish. Relatively fewer studies have been conducted on marine organisms, particularly economically important shellfish. So, this study is innovative and necessary. This study provides a biochemical, metabolomic, and nutritional analysis of DMP, DBP, and DEHP toxic effects on mussels, and supports the ecotoxicology of PAEs on marine organisms.

Insights into pollution characteristics and human health risks of plasticizer phthalate esters in shellfish species

The ubiquitous application of phthalate esters (PAEs) as plasticizers contributes to high levels of marine pollution, yet the contamination patterns of PAEs in various shellfish species remain unknown. The objective of this research is to provide the first information on the pollution characteristics of 16 PAEs in different shellfish species from the Pearl River Delta (PRD), South China, and associated health risks. Among the 16 analyzed PAEs, 13 were identified in the shellfish, with total PAE concentrations ranging from 23.07 to 3794.08 ng/g dw (mean = 514.35 ng/g dw). The PAE pollution levels in the five shellfish species were as follows: Ostreidae (mean = 1064.12 ng/g dw) > Mytilus edulis (mean = 509.88 ng/g dw) > Babylonia areolate (mean = 458.14 ng/g dw) > Mactra chinensis (mean = 378.90 ng/g dw) > Haliotis diversicolor (mean = 335.28 ng/g dw). Dimethyl phthalate (DMP, mean = 69.85 ng/g dw), diisobutyl phthalate (DIBP, mean = 41.39 ng/g dw), dibutyl phthalate (DBP, mean = 130.91 ng/g dw), and di(2-ethylhexyl) phthalate (DEHP, mean = 226.23 ng/g dw) were the most abundant congeners. Notably, DEHP constituted the most predominant fraction (43.98 %) of the 13 PAEs detected in all shellfish from the PRD. Principal component analysis indicated that industrial and domestic emissions served as main sources for the PAE pollution in shellfish from the PRD. It was estimated that the daily intake of PAEs via shellfish consumption among adults and children ranged from 0.004 to 1.27 μg/kgbw/day, without obvious non-cancer risks (< 0.034), but the cancer risks raised some alarm (2.0 × 10-9-1.4 × 10-5). These findings highlight the necessity of focusing on marine environmental pollutants and emphasize the importance of ongoing monitoring of PAE contamination in seafood.

High concentrations of phthalates affect the early development of the sea urchin Paracentrotus lividus

The toxicity of three phthalates (PAEs) - butylbenzyl phthalate (BBP), diethyl phthalate (DEP), and di-(2-ethylhexyl) phthalate (DEHP) - was tested on the Mediterranean sea urchin Paracentrotus lividus. Fertilized eggs were exposed to environmental and high PAE concentrations for 72 h. The potential toxic effects on larval development and any morphological anomalies were then assessed to estimate PAEs impact. Environmental concentrations never affected development, while high concentrations induced toxic effects in larvae exposed to BBP (EC50: 2.9 ×103 µg/L) and DEHP (EC50: 3.72 ×103 µg/L). High concentrations caused skeletal anomalies, with a slight to moderate impact for DEP/DEHP and BBP, respectively. PAE toxicity was: BBP>DEHP>DEP. In conclusion, the three PAEs at environmental concentrations do not pose a risk to sea urchins. However, PAE concentrations should be further monitored in order not to constitute a concern to marine species, especially at their early developmental stages.

Comparison of phthalate esters (PAEs) in freshwater and marine food webs: Occurrence, bioaccumulation, and trophodynamics

Phthalate esters (PAEs) have received widespread attentions due to their ubiquity in various kinds of matrices and potential biotoxicity. This study systematically compared the concentrations, bioaccumulation, trophodynamics and health risk of PAEs in 25 species (n = 225) collected from a marine (Bohai Bay, BHB) and freshwater environment (Songhua River, SHR), China. Results showed that di-(2-ethylhexyl) phthalate and di-n-butyl phthalate were the predominant PAEs in the organisms from the two aquatic environments. The total concentrations of 6 PAEs in algae and fish from SHR were significantly higher than those from BHB. Two food webs were constructed in BHB and SHR based on the abundance of 15N in the organisms. All the PAEs except dimethyl phthalate exhibited trophic dilution with the trophic magnification factors less than 1. Moreover, an obvious biodilution of PAEs was observed in marine food web compared to freshwater food web. A low health risk of PAEs was found in organisms from both BHB and SHR. However, di-(2-ethylhexyl) phthalate exhibited a potential carcinogenic risk by consumption of some benthos in BHB and fish in SHR. This study provides a valuable perspective for understanding the trophodynamics and health risk of PAEs in marine and freshwater environments.

Emerging and legacy plasticisers in coastal and estuarine environments: A review

The occurrence of plastic waste in the environment is an emerging and ongoing concern. In addition to the physical impacts of macroplastics and microplastics on organisms, the chemical effects of plastic additives such as plasticisers have also received increasing attention. Research concerning plasticiser pollution in estuaries and coastal environments has been a particular focus, as these environments are the primary entry point for anthropogenic contaminants into the wider marine environment. Additionally, the conditions in estuarine environments favour the sedimentation of suspended particulate matter, with which plasticisers are strongly associated. Hence, estuary systems may be where some of the highest concentrations of these pollutants are seen in freshwater and marine environments. Recent studies have confirmed emerging plasticisers and phthalates as pollutants in estuaries, with the relative abundance of these compounds controlled primarily by patterns of use, source intensity, and fate. Plasticiser profiles are typically dominated by mid-high molecular weight compounds such as DnBP, DiBP, and DEHP. Plasticisers may be taken up by estuarine and marine organisms, and some phthalates can cause negative impacts in marine organisms, although further research is required to assess the impacts of emerging plasticisers. This review provides an overview of the processes controlling the release and partitioning of emerging and legacy plasticisers in aqueous environments, in addition to the sources of plasticisers in estuarine and coastal environments. This is followed by a quantitative analysis and discussion of literature concerning the (co-)occurrence and concentrations of emerging plasticisers and phthalates in these environments. We end this review with a discussion the fate (degradation and uptake by biota) of these compounds, in addition to identification of knowledge gaps and recommendations for future research.

Butyl benzyl phthalate induced reproductive toxicity in the endoplasmic reticulum and oxidative stress in Brachionus plicatilis Müller, 1786

To study the adverse effects of butyl benzyl phthalate (BBP) on Brachionus plicatilis, rotifers were exposed to different BBP concentrations (0 [control], 0.001, 0.01, 0.1, and 1 mg/L). We measured the activities of the antioxidant enzymes superoxide dismutase, catalase, and reduced glutathione, which play a key role in detoxification, and the malondialdehyde content, which represents the level of lipid peroxidation. In addition, we investigated the effect of BBP on the submicroscopic structure and transcriptome of rotifer ovary cells. Our results showed that B. plicatilis exhibited a rapid oxidative stress response accompanied by a significant increase in superoxide dismutase enzyme activity. High BBP concentrations resulted in a significant decrease in malondialdehyde content, which indicated that BBP interferes with the lipid metabolism of rotifer cells. Our observations showed that the endoplasmic reticulum structure of rotifer ovary cells was severely damaged by BBP exposure. Transcriptomic data further demonstrated that oxidative stress and cellular sub-microstructural damage were associated with altered expression of functional genes related to rotifer redox regulation, biosynthetic processes, and cellular damage components. In conclusion, our study demonstrates that BBP triggers changes in antioxidant-related indicators in rotifers; this leads to activation of related genes and subsequent changes in intracellular signaling, which in turn triggers endoplasmic reticulum stress and ultimately leads to disruption of cell function and structure. These findings highlight the potential risks associated with BBP exposure and provide fundamental insights into its toxicological effects on marine invertebrates.

Re-evaluation of the taxonomic status of four nominal, western Pacific species of tongue soles (Pleuronectoidei: Cynoglossidae: Cynoglossus), with redescription of C. joyneri Gnther, 1878

Striking similarities in morphological characters and significant overlap in meristic features have resulted in different hypotheses regarding the taxonomic status of several nominal species of northwestern Pacific tongue soles of the genus Cynoglossus, including C. joyneri Gnther, 1878, C. lighti Norman, 1925, C. tenuis (Oshima, 1927), and C. tshusanensis Chabanaud, 1951. Previous hypotheses have proposed that each taxon is a valid species; or that C. lighti and C. tshusanensis are junior subjective synonyms of C. joyneri; or that C. tenuis is a junior subjective synonym of either C. joyneri or C. lighti. Although several previous investigations concluded that C. lighti is a synonym of C. joyneri, names of both nominal species still appear in contemporary literature indicating that taxonomic status of these nominal species remains unresolved. To clarify the taxonomic status of these four nominal species, detailed study of morphological characters of 138 specimens collected from 22 localities in Japan and China, and re-examination of type specimens of three of these nominal species was conducted. The molecular barcodes of mitochondrial DNA from six representative specimens featuring morphological variation purportedly useful for distinguishing C. lighti from C. joyneri were also analyzed and then compared with sequences reported for C. joyneri in the literature. Lectotypes of C. joyneri and C. lighti differed in only two morphological characters (body depth and position of posterior tip of rostral hook relative to anterior margin of lower eye). However, when these two characters were examined in 138 recently collected non-type specimens, no differences were found among these nominal species. Our results do not support recognizing these as separate species. Results from genetic analyses also support recognizing only a single species among the material examined. Furthermore, overall similarities in morphological features between the holotype of C. tshusanensis and specimens of C. joyneri support recognizing C. tshusanensis as a junior subjective synonym of C. joyneri. Likewise, values for morphological features of C. joyneri examined in the present study also encompass the range of values reported in the original description of C. tenuis. This finding supports conclusions of previous studies that this nominal species is also a junior synonym of C. joyneri. Based on morphological and genetic evidence, we conclude that only a single species, C. joyneri, should be recognized among the four nominal species included in this study. Cynoglossus joyneri is re-described based on data from 492 specimens collected throughout nearly the entire range of the species.

Effect of an environmental microplastic mixture from the Seine River and one of the main associated plasticizers, dibutylphthalate, on the sentinel species Hediste diversicolor

The aim of this study was to explore the adverse effects of a microplastic (MP) mixture obtained from litter accumulated in the Seine River (France) compared to those of their major co-plasticizer, dibutylphthalate (DBP), on the sentinel species Hediste diversicolor. A suite of biomarkers has been investigated to study the impacts of MPs (100 mg kg-1 sediment), DBP (38 μg kg-1 sediment) on worms compared to non-exposed individuals after 4 and 21 days. The antioxidant response, immunity, neurotoxicity and energy and respiratory metabolism were investigated using biomarkers. After 21 days, worms exposed to MPs showed an increasing aerobic metabolism, an enhancement of both antioxidant and neuroimmune responses. Energy-related biomarkers demonstrated that the energy reallocated to the defence system may come from proteins. A similar impact was depicted after DBP exposure, except for neurotoxicity. Our results provide a better understanding of the ecotoxicological effects of environmental MPs and their associated-contaminants on H. diversicolor.

Riverine inputs, spatiotemporal variations, and potential sources of phthalate esters transported into the Bohai Sea from an urban river in northern China

The effects of anthropogenic activities on pollutant transport and inputs to the sea remain unclear. This study aimed to evaluate the impacts of sewage discharge and dam interception on riverine inputs, spatiotemporal variations, and potential sources of phthalate esters (PAEs) throughout the Haihe River, one of the largest rivers in northern China. Based on seasonal observations, the yearly inputs of the total concentrations of 24 PAE species (Σ₂₄PAEs) from the Haihe River to the adjacent Bohai Sea were in the range of 5.28-19.52 tons, a considerable amount compared with those of other large rivers worldwide. The value of Σ₂₄PAEs in the water column ranged from 1.17 to 15.46 μg/L and showed the following overall seasonal pattern: normal season > wet season > dry season, with dibutyl phthalate (DBP) (31.0 ± 11.9 %), di (2-ethylhexyl) phthalate (DEHP) (23.4 ± 14.1 %), and diisobutyl phthalate (DIBP) (17.2 ± 5.4 %) as the dominant components. Σ₂₄PAEs were higher in the surface layer, slightly lower in the intermediate layer, and higher in the bottom layer. Σ₂₄PAEs increased from the suburban section to the urban and industrial sections, which may indicate the effects of runoff, biodegradation, regional urbanization, and industrialization levels. The Erdaozha Dam intercepted 0.29-1.27 tons of Σ₂₄PAEs inputs into the sea, but induced a substantial quantity accumulated behind the dam. The dominant sources of PAEs were the basic residential necessities (18.2-25.5 %) and industrial production (29.1-53.0 %). This study provides insights into the direct effects of sewage discharge and river dams on the inputs and variations in the PAEs entering the sea, which can be leveraged to manage and control PAEs in megacities.

Organophosphate esters in the seawater of the Bohai Sea: Environmental occurrence, sources and ecological risks

Organophosphate esters (OPEs) are widely distributed in surface water systems, but limited information was available on the spatial occurrence and ecological risks of OPEs in the Bohai Sea. In this study, 89 water samples in the Bohai Sea and the five surrounding rivers were investigated for the determination of 15 OPEs. The concentration of ∑₁₅OPEs ranged from 373.20 to 2931.27 ng·L^-1 in the river water and 137.81 to 2641.30 ng·L^-1 in the seawater, with high levels of OPEs in Liaodong Bay. Tris(2-chloroethyl) phosphate (TCEP, 10- 92 %) and triethyl phosphate (TEP, 5- 64 %) were dominant for OPEs. The correlation analysis, principal component analysis and hierarchical cluster analysis suggested the conjunction of municipal wastewater via river input and maritime shipping was the main source of OPEs in the Bohai Sea. The ecological risk assessment indicated that the individual OPEs arise low ecological risks in the Bohai Sea, while medium ecological risks of ∑₁₅OPEs are in minority river samples.

Comprehensive investigation and risk assessment of organic contaminants in Yellow River Estuary using suspect and nontarget screening strategies

Contaminants of emerging concerns (CECs) include numerous chemicals that may pose known and unknown risks to the ecosystem, and identification and risk ranking of these compounds is essential for the environmental management. In this study, liquid and gas chromatography time-of-flight mass spectrometry (LC-QTOF-MS and GC-QTOF-MS) were used to characterize the occurrence of CECs in the surface water of the Yellow River Estuary (YRE). A total of 295 and 315 chemicals were identified by LC-QTOF-MS and GC-QTOF-MS, respectively. The occurrence of two compounds, erucamide and 2-phenylquinoline, was for the first time reported in the aquatic environment in YRE. The concentrations of 121 CECs, including 35 antibiotics, 49 pesticides and veterinary, 16 polycyclic aromatic hydrocarbons and 21 phthalic acid esters were further quantified by target analysis, which showed the detection of 99 compounds in the surface water in the range of 7.07-4611.26 ng/L. Ecological risks of pollutants based on the risk quotient (RQ) method revealed that 13 pollutants posed ecological risks to the aquatic ecosystem (RQ > 1), and pesticides (n = 12) were the main risk contributors. Here, all CECs data sets were finally transformed and ranked in the framework of the toxicological priority index (ToxPi), and a total of 81 priority control pollutants were identified in the surface water of YRE. This study highlighted the necessity of suspect and nontarget screening for CECs in estuaries, and revealed the importance of localized contamination sources in urban and agricultural environment.

Distribution, Source Apportionment and Risk Assessment of Phthalate Esters in the Overlying Water of Baiyang Lake, China

As a kind of endocrine disruptor compounds, the presence of phthalate esters (PAEs) has become a global concern. In this study, the pollution levels and spatial distribution of sixteen PAEs were investigated. Their potential sources and eco-environmental health risk were discussed in Baiyang Lake and its upstream rivers during different periods. PAEs were detected in all of samples, ranging from 1215 to 3014 ng·L-1 in October 2020 and 1384 to 3399 ng·L-1 in May 2021. Dibutyl phthalate (DBP) and di-isobutyl phthalate (DIBP) were the predominant monomers, with a detection rate of 100% and the highest concentrations in the overlying water. Restricted by multiple factors, the spatial distribution difference between Baiyang Lake and its upstream rivers in October was more significant than in May. The source apportionment revealed that agricultural cultivation and disorderly use and disposal of plastic products were the primary factors for the contamination. The human health risk assessment indicated that eight PAE congeners did not pose significant carcinogenic and non-carcinogenic harms to males, females and children. However, the ecological risks of DBP, DIBP and di (2-ethylhexyl) phthalate to algae, crustaceans and fish species were moderate or high-risk levels. This study provides an appropriate dataset for the assessment of the pollution of PEs to the water ecosystem affected by anthropogenic activities.

Thyroid hormone disruption by bis-(2-ethylhexyl) phthalate (DEHP) and bis-(2-ethylhexyl) adipate (DEHA) in Japanese medaka Oryzias latipes

Pollution of water bodies with plasticizers is a serious environmental problem worldwide. In this study, we investigated the effects of plasticizers bis-(2-ethylhexyl) phthalate (DEHP) and bis-(2-ethylhexyl) adipate (DEHA) in Japanese medaka (Oryzias latipes). DEHP significantly increased the expression of all the genes tested: thyroid stimulating hormone beta subunit (tshβ-like), tshβ, deiodinase 1 (dio1), deiodinase 2 (dio2), and thyroid hormone receptor alpha (trα) and beta (trβ). However, DEHA only significantly increased tshβ at 7.4 µg/L but significantly decreased dio2 expression at 25.8, 111.1, and 412.6 4 µg/L, while other genes were not significantly affected. Both chemicals reduced eye size and total body length, but did not affect embryo development, hatching time and rate, and swimming performance. DEHA alone affected swim bladder inflation and not DEHP. This is the first report that not only DEHP but also DEHA disrupt thyroid hormone activity in fish. DEHP contamination (13.2 μg/L) was detected in tap water from Kobe, Japan; thus, tap water itself may disrupt thyroid hormone activity in Japanese medaka. Importantly, the effective concentration of DEHP for thyroid hormone-related gene expression and growth was close to or lower than DEHP concentrations reported in surface water elsewhere, indicating that DEHP contamination is a serious aquatic pollution.

Development of ecological risk assessment for Diisobutyl phthalate and di-n-octyl phthalate in surface water of China based on species sensitivity distribution model

Phthalic acid esters (PAEs) are commonly used as plasticizer and are emerging concern worldwide for potent adverse effects of aquatic organisms. Certain PAEs were often detected in different environmental matrices but related toxicity data were still lacking to support their risk assessment. The study investigated the acute toxicity of Diisobutyl phthalate (DiBP) and Di-n-octyl phthalate (DnOP) using 6 Chinese resident aquatic organisms from 3 phyla and 6 species and constructed the species sensitivity distribution (SSD) models for ecological risk assessment. Lethal concentration 50% (LC₅₀) ranges of DiBP and DnOP were 4.89-21.45 mg/L and 1.45-1200 mg/L, respectively. The derived acute and chronic predicted no-effect concentrations (PNECs) based on log-normal model of water were 0.54 and 0.04 mg/L for DiBP and 0.23 and 0.05 mg/L for DnOP, respectively. The ERA for DiBP and DnOP in the surface water and sediment of China was conducted. Water samples of Haihe Rive (RQ = 0.41) and Hun River (RQ = 0.16) of DiBP showed medium risk. And sediment samples of Yellow River (RQ = 0.71) and Chao Hu Lake (RQ = 0.42) of DiBP showed medium risk. Meanwhile, the above water and sediment samples (RQ＜0.1) of DnOP showed low risk.

Effect of dibutyl phthalate on microalgal growth kinetics, nutrients removal, and stress enzyme activities

The dibutyl phthalate (DPB) is an emerging plasticizer contaminant that disrupts the biological processes of primary producers, especially phytoplankton. In this study, two microalgal species (Chlorella sp. GEEL-08 and Tetradesmus dimorphus GEEL-04) were exposed to various concentrations of DBP extending from 0 to 100 mg/L. The growth kinetics, N-nitrate, and P-phosphate removal efficiency were assessed. The response enzymes such as malonaldehyde (MDA) and superoxide dismutase (SOD) were also investigated. The results revealed that the Chlorella sp. GEEL-08 at 10 mg/L concentration of DBP exhibited higher growth (0.88 OD680nm) compared to T. dimorphus GEEL-04 (0.80 OD680nm). More than 94% of N and P were removed from culture media by both microalgal species. The DBP (>50 mg/L) significantly exacerbates the growth of both microalgae species and the growth inhibition ratio was in the range of 3.6%-25.9%. The SOD activity and MDA were higher in T. dimorphus culture media than in the culture media of Chlorella sp. The results reflect the hazard and the risk of plasticizers on primary producers in the ecosystem.

Phthalate esters (PAEs) concentration pattern reflects dietary habitats (δ13C) in blood of Mediterranean loggerhead turtles (Caretta caretta)

Phthalic acid esters (PAEs) are classified as endocrine disruptors, but it remains unclear if they can enter the marine food-web and result in severe health effects for organisms. Loggerhead turtles (Caretta caretta) can be chronically exposed to PAEs by ingesting plastic debris, but no information is available about PAEs levels in blood, and how these concentrations are related to diet during different life stages. This paper investigated, for the first time, six PAEs in blood of 18 wild-caught Mediterranean loggerhead turtles throughout solid-phase extraction coupled with gas chromatography-ion trap/mass spectrometry. Stable isotope analyses of carbon and nitrogen were also performed to assess the resource use pattern of loggerhead turtles. DEHP (12-63 ng mL^-1) and DBP (6-57 ng mL^-1) were the most frequently represented PAEs, followed by DiBP, DMP, DEP and DOP. The total PAEs concentration was highest in three turtles (124-260 ng mL^-1) whereas three other turtles had concentrations below the detection limit. PAEs were clustered in three groups according to concentration in all samples: DEHP in the first group, DBP, DEP, and DiBP in the second group, and DOP and DMP in the third group. The total phthalates concentration did not differ between large-sized (96.3 ± 86.0 ng mL^-1) and small-sized (67.1 ± 34.2 ng mL^-1) turtles (p < 0.001). However, DMP and DEP were found only in large-sized turtles and DiBP and DBP had higher concentrations in large-sized turtles. On the other hand, DEHP and DOP were found in both small- and large-sized turtles with similar concentrations, i.e. ~ 21.0/32.0 ng mL^-1 and ~ 7^.1/9.9 ng mL^-1, respectively. Winsored robust models indicated that δ¹³C is a good predictor for DBP and DiBP concentrations (significant Akaike Information criterion weight, AIC_wt). Our results indicate that blood is a good matrix to evaluate acute exposure to PAEs in marine turtles. Moreover, this approach is here suggested as a useful tool to explain the internal dose of PAEs in term of dietary habits (δ¹³C), suggesting that all marine species at high trophic levels may be particularly exposed to PAEs, despite their different dietary habitats and levels of exposure.

Contamination and ecological risk of microplastics and phthalates in the surface water of the Tha Dee Sub-River basin, Nakhon Si Thammarat Province, Thailand

Plastic waste has become a significant source of water pollution worldwide, releasing microplastics (MPs) and hazardous chemicals into aquatic environments. The purpose of this study was to determine the occurrence and ecological risk of MPs and phthalates (PAEs) in the surface water of the Tha Dee Sub-River basin in Nakhon Si Thammarat Province, Thailand. MPs, PAEs, and water quality parameters, including turbidity, pH, conductivity, dissolved oxygen, and salinity, were investigated simultaneously at 26 sampling stations. The average number of MPs per liter was 0.5 ± 0.4. Filaments were the most common MPs (59%), and transparent/white was the most prevalent color (51%). Four PAEs were found, with an average total concentration of 25.78 ± 93.87 µg/L, and diethyl phthalate was observed in the highest concentrations. Although there was no association between PAEs and other parameters, there was a significant correlation among particular PAEs (P < 0.05), indicating that they came from the same source. The pollution load index of MPs indicated a minor risk, but PAEs posed a medium risk to fish in the study area. This study's findings suggest that further research into the sources of PAEs and their contamination of aquatic life is needed.

Acute toxicity of bioplastic leachates to Paracentrotus lividus sea urchin larvae

In an attempt to ensure that bioplastics, progressively replacing petrochemical-derived plastics, do not release any harmful compound to the environment, the study assessed the toxic effects of three innovative bioplastic products: polyhydroxybutyrate resin (PHB), polylactic acid cups (PLA) and a polylactic acid/polyhydroxyalkanoate 3D printing filament (PLA/PHA), together with a synthetic polyvinyl chloride (PVC) toy in Paracentrotus lividus sea urchin larvae. PVC toy was the most toxic material, likely due to the added plasticizers; remarkably, even if PHB is conceived as a nontoxic polymer, it showed a slight toxicity and Gas Chromatography-Mass Spectometry analysis (GC-MS) revealed the presence of a wide range of additives. Conversely, PLA cups and PLA/PHA filament were innocuous for the larvae, a positive outcome for these renewable solutions. Proven that additives are also used in some bioplastic formulations, they should be carefully addressed to ensure that they are as safe as regarded.

Fast determination of phthalates in mussel samples by micro-matrix solid-phase dispersion (micro-MSPD) coupled with GC–MS/MS

A fast, effective and low cost sample preparation method based on miniaturized matrix solid-phase dispersion (micro-MSPD) combined with gas chromatography coupled to tandem triple-quadrupole-mass spectrometry (GC–MS/MS) has been developed for the determination of six phthalate diesters (DMP, DEP, DBP, BzBP, DEHP and DnOP) in mussel samples. The six target compounds have been included in the list of priority pollutants by United States Environmental Protection Agency. The extraction step was optimized on real spiked mussel coming from Galician Rías by means of a factorial design. The final procedure involved the use of 0.45 g of sample, 0.5 g of dispersant agent (Florisil) and 3 mL of organic solvent (ethyl acetate). The optimized method was validated giving satisfactory analytical performance, low detection limits (0.09 to 6.73 ng g−1 dw) and high recoveries (93 and 114%). The validated method was applied to four real mussel samples coming from Galician Rías.

Fast and Reliable Determination of Phthalic Acid Esters in the Blood of Marine Turtles by Means of Solid Phase Extraction Coupled with Gas Chromatography-Ion Trap/Mass Spectrometry

The presence of phthalic acid esters (PAEs) in marine environments is an important issue. These chemicals are able to affect marine organisms, particularly marine turtles, and to act as endocrine disrupters. In this paper, for the first time, a simple and reproducible analytical method based on solid-phase extraction (SPE) coupled with gas chromatography-ion trap/mass spectrometry (GC-IT/MS) was developed for the extraction of phthalates from the blood of marine turtles. The extraction was obtained by using C₁₈ phthalates-free as the stationary phase. In order to individuate the best working conditions for the extraction, the adsorption isotherms and breakthrough curves were studied. The overall analytical methodology was validated in terms of limit of detection (LOD, 0.08-0.6 ng mL^-1), limit of quantification (LOQ, 0.4-0.8 ng mL^-1), and correlation coefficients (>0.9933). By using this procedure, percentage recoveries ranging from 89 to 103% were achieved. The precision parameters (intra-day and inter-day) were studied, and the obtained values were smaller than 12.5%. These data confirm the goodness of the proposed analytical methodology, which is applied to real samples.