Evaluation of microplastic pollution using bee colonies: An exploration of various sampling methodologies.

Recent research has highlighted the potential of honeybees and bee products as biological samplers for monitoring xenobiotic pollutants. However, the effectiveness of these biological samplers in tracking microplastics (MPs) has not yet been explored. This study evaluates several methods of sampling MPs, using honeybees, pollen, and a novel in-hive passive sampler named the APITrap. The collected samples were characterized using a stereomicroscopy to count and categorise MPs by morphology, colour, and type. To chemical identification, a micro-Fourier transform-infrared (FTIR) spectroscopy was employed to determine the polymer types. The study was conducted across four consecutive surveillance programmes, in five different apiaries in Denmark. Our findings indicated that APITrap demonstrated better reproducibility, with a lower variation in results of 39%, compared to 111% for honeybee samples and 97% for pollen samples. Furthermore, the use of APITrap has no negative impact on bees and can be easily applied in successive samplings. The average number of MPs detected in the four monitoring studies ranged from 39 to 67 in the APITrap, 6 to 9 in honeybee samples, and 6 to 11 in pollen samples. Fibres were the most frequently found, accounting for an average of 91% of the total MPs detected in the APITrap, and similar values for fragments (5%) and films (4%). The MPs were predominantly coloured black, blue, green and red. Spectroscopy analysis confirmed the presence of up to five different synthetic polymers. Polyethylene terephthalate (PET) was the most common in case of fibres and similarly to polypropylene (PP), polyethylene (PE), polyacrylonitrile (PAN) and polyamide (PA) in non fibrous MPs. This study, based on citizen science and supported by beekeepers, highlights the potential of MPs to accumulate in beehives. It also shows that the APITrap provides a highly reliable and comprehensive approach for sampling in large-scale monitoring studies.

Evaluation of the sorption/desorption processes of pesticides in biodegradable mulch films used in agriculture.

Microplastics from mulch films can be a source of chemical contamination to agricultural soils. In this context, biodegradable films have been widely positioned as a greener choice. However, their sorption/desorption capabilities, in contrast to the conventional plastic types remain understudied. It is for this reason that objective evaluation of their interactions with residual agricultural contaminants becomes important. Our findings reveal that polyethylene (PE) mulch films retained lower amounts of pesticide residues and demonstrated a higher desorption/release [median desorption = 71.86 µg/L or about 50%], while polybutylene adipate terephthalate (PBAT) mulch films retained higher amounts of pesticide residues onto their surface and demonstrated a much lower desorption [median desorption = 24.27 µg/L or about 17%] after a spraying event. A higher ambient temperature had no significant effect on final desorption amounts in both PE [median = 65.27 µg/L at 20 °C and 74.23 µg/L at 40 °C] and PBAT [median = 24.26 µg/L at 20 °C and 24.78 µg/L at 40 °C] mulch films. However, it did favour a faster desorption pace in PE films. Desorption in PBAT and PE plastic types was correlated with the log Kow value [Spearman's correlation: 0.857 and 0.837 respectively, p < 0.05]. However, only a moderate correlation with pKa was observed in PBAT [Spearman's correlation: 0.478, p < 0.05], while none for PE plastic type. Sorption of pesticides onto biodegradable PBAT microplastics were best explained by Elovich [R2: 0.937-0.959] and pseudo-second order kinetics [R2: 0.942-0.987], suggesting the presence of chemisorption. Furthermore, Weber Morris plots suggested the presence of a multi-step process and Boyd plots indicated that film diffusion or chemical bond formation was the rate-limiting step governing this phenomenon.

Validation of a quick and easy extraction method for the determination of emerging contaminants and pesticide residues in agricultural soils.

Treated wastewater is currently used in the agricultural sector to solve the lack of availability of freshwater in many regions. However, reclaimed water can contain multiclass of organic contaminants. Therefore, the soil can become a reservoir of agricultural (e.g. pesticides) and urban (e.g. pharmaceuticals) contaminants. Consequently, the evaluation of this contamination process is necessary for assessing its potential human and environmental negative effects. Due to the low concentration levels, different chemical properties and the complexity of the matrix, an efficient sample preparation step for achieving adequate sensitivity and robust analysis in the soil is needed. The aim of this study was to develop a quick and easy extraction method based on a QuEChERS procedure for the determination of 27 organic contaminants in agricultural soil samples. The procedure was based on a salting-out extraction with acidified acetonitrile, followed by a dispersive solid-phase extraction (d-SPE). A liquid chromatography-tandem mass-spectrometry (LC-MS/MS) system was applied for the determination and quantification of the selected target analytes. The main benefits of this analytical approach are:•Reduction/elimination of majority of the interferences improving the sensitivity of the method.•Robust simultaneous determination of a multiclass of organic contaminants with very different physicochemical properties.

In vivo exposure of marine mussels to venlafaxine: bioconcentration and metabolization.

Pharmaceuticals are present in natural waters, thus contributing to the general exposure of aquatic organisms, but few data are available on the accumulation of these substances in marine organisms. The present study evaluated the in vivo bioconcentration of an antidepressant-venlafaxine (VLF)-in marine mussels (Mytilus galloprovincialis) during 7 days of exposure at nominal 10 µg/L concentration, followed by a 7-day depuration period. The bioconcentration factor (BCF) was 265 mL/g dry weight (dw). VLF accumulation reached an average tissue concentration of 2146 ± 156 ng/g dw within 7 days, showing a first-order kinetics process. N-desmethylvenlafaxine (N-VLF) and O-desmethylvenlafaxine (O-VLF) metabolites were quantified in mussel tissues, whereas N,N-didesmethylvenlafaxine (NN-VLF) was only recorded as being detected. These three metabolites were also quantified in water, indicating an active metabolism and VLF excretion in Mediterranean mussels. Complementary experiments conducted at nominal concentrations of 1, 10, and 100 µg/L for 7 days confirmed the VLF bioconcentration and metabolism and allowed us to quantify a supplementary metabolite, i.e., N,O-didesmethylvenlafaxine (NO-VLF), in mussel tissues. These results encourage further research on a more complete characterization of metabolism and on any disturbances linked to bioconcentration of VLF on bivalves.

Pesticide residues evaluation of organic crops. A critical appraisal.

In the last decade, the consumption trend of organic food has increased dramatically worldwide. Since only a few pesticides are authorized in organic crops, concentrations are expected to range at zero or ultra-trace levels. In this context, the aim of the present study was to investigate the need for an improvement in the residue controls at very low concentrations (<0.010 mg kg-1) and to assess the impact of the scope of the analytical methods for this type of crops. For that purpose, a monitoring study for fruit and vegetable samples covering a wide range of pesticides (3 2 8) at low LOQs (0.002-0.005 mg kg-1) was developed. The results showed that the impact of applying analytical methods with low LOQs was not very relevant in the majority of the cases. However, a wide scope presented a high influence on this evaluation, especially regarding the inclusion of very polar compounds and metabolites.

A non-targeted metabolomic approach to identify food markers to support discrimination between organic and conventional tomato crops.

In the last decade, the consumption trend of organic food has increased dramatically worldwide. However, the lack of reliable chemical markers to discriminate between organic and conventional products makes this market susceptible to food fraud in products labeled as "organic". Metabolomic fingerprinting approach has been demonstrated as the best option for a full characterization of metabolome occurring in plants, since their pattern may reflect the impact of both endogenous and exogenous factors. In the present study, advanced technologies based on high performance liquid chromatography-high-resolution accurate mass spectrometry (HPLC-HRAMS) has been used for marker search in organic and conventional tomatoes grown in greenhouse under controlled agronomic conditions. The screening of unknown compounds comprised the retrospective analysis of all tomato samples throughout the studied period and data processing using databases (mzCloud, ChemSpider and PubChem). In addition, stable nitrogen isotope analysis (δ15N) was assessed as a possible indicator to support discrimination between both production systems using crop/fertilizer correlations. Pesticide residue analyses were also applied as a well-established way to evaluate the organic production. Finally, the evaluation by combined chemometric analysis of high-resolution accurate mass spectrometry (HRAMS) and δ15N data provided a robust classification model in accordance with the agricultural practices. Principal component analysis (PCA) showed a sample clustering according to farming systems and significant differences in the sample profile was observed for six bioactive components (L-tyrosyl-L-isoleucyl-L-threonyl-L-threonine, trilobatin, phloridzin, tomatine, phloretin and echinenone).

Diurnal variations in personal care products in seawater and mussels at three Mediterranean coastal sites.

The presence of personal care products (PCPs) in the marine environment is of major concern. PCPs, UV filters, and musks can enter the marine environment indirectly through wastewater or directly via recreational activities. We conducted this study to document patterns in the occurrence of seven PCPs at three coastal sites impacted by recreational activities during 1 day. The study focused on diurnal variations in these seven PCPs in seawater and indigenous mussels. In seawater, UV filters showed diurnal variations that mirrored variations in recreational activities at the sites. Ethylhexyl methoxycinnamate (EHMC) and octocrylene (OC) water concentrations increased from under the limit of quantification in the morning to 106 and 369 ng/L, respectively, when recreational activities were the highest. In mussels, diurnal variations in OC were observed, with the lowest concentrations recorded in the morning and then increasing throughout the day. As Mytilus spp. are widely used as sentinels in coastal pollution monitoring programs (mussel watch), our findings on diurnal variations could enhance sampling recommendations for recreational sites impacted by PCPs.

Reducing PEC uncertainty in coastal zones: a case study on carbamazepine, oxcarbazepine and their metabolites.

Concentrations of the antiepileptic drugs carbamazepine (Cbz), oxcarbazepine (OxCz) and their main metabolites were predicted in a wastewater treatment plant (WTP) and in the vicinity of its submarine outfall located in a Mediterranean coastal zone. Refined predicted environmental concentrations (PECs) were calculated in effluents based on consumption data and human excretion rates. PECs were estimated in the sea using the hydrodynamic MARS 3D model integrating meteorological data, oceanic conditions (wind, tide, atmospheric pressure), freshwater and sewage inputs. Measured environmental concentrations (MECs) were compared to PECs to assess the estimation relevance. In the coastal zone, PEC and MEC were in the same magnitude range. Modeling of Cbz diffusion and advection just above the submarine outfall showed the influence of the thermocline during summer, with low diffusion of Cbz from the bottom to the surface. This work allowed understanding the dispersion of target compounds and deserved further development for a better acknowledgement of vulnerability at local scales.

Quantitative determination of poly(amidoamine) dendrimers in urine by liquid chromatography/electrospray ionization hybrid quadrupole linear ion trap mass spectrometry.

RATIONALE: Dendrimer nanocarriers have become of increasing interest in the field of biomedicine for their drug delivery potential. Surface modifications and optimized nanosize control are the strategies being followed to enhance drug delivery efficacy and renal clearance, especially for dendrimers of a lower generation number. The aim of this study was the development and performance evaluation of an analytical method for the quantitative determination of polyamidoamine (PAMAM) dendrimers in urine. METHODS: PAMAM dendrimers (generations G0 to G3) were analyzed using liquid chromatography/electrospray ionization hybrid quadrupole linear ion trap mass spectrometry (LC/ESI-QqLIT-MS). Quantitative analysis was performed in selected reaction monitoring (SRM) mode. To confer a higher degree of confidence on the identification of PAMAM dendrimers, an SRM scan and collision-induced dissociation (CID), as a dependent scan, were performed in one single run using the information-dependent acquisition (IDA) mode. RESULTS: The LC/ESI-QqLIT-MS method, in SRM mode, allowed quantitative determination in urine matrix with good repeatability and reproducibility (relative standard deviation (R.S.D.) from 2 to 15%), linearity (R >0.99) over the concentration range (6∙10-4 to 5∙10-2 mmol.L-1 ), and sensitivity within the micromolar range. The detection limit values were above 1∙10-4 mmol.L-1 in both solvent and urine, for the generations studied. CONCLUSIONS: The developed method has demonstrated a capability for the identification and quantification of PAMAM dendrimer nanoparticles in a complex liquid matrix. The use of an LC/ESI-QqLIT-MS system, of modest m/z range and unit resolution, offers an alternative in the analysis of lower generation PAMAM dendrimers between mass analyzers of higher resolution and the conventional LC-UV method that is commonly applied for dendrimer quantification, but which lacks sufficient identification capacity. Copyright © 2013 John Wiley & Sons, Ltd.

New trends in the analytical determination of emerging contaminants and their transformation products in environmental waters.

Since the so-called emerging contaminants were established as a new group of pollutants of environmental concern, a great effort has been devoted to the knowledge of their distribution, fate and effects in the environment. After more than 20 years of work, a significant improvement in knowledge about these contaminants has been achieved, but there is still a large gap of information on the growing number of new potential contaminants that are appearing and especially of their unpredictable transformation products. Although the environmental problem arising from emerging contaminants must be addressed from an interdisciplinary point of view, it is obvious that analytical chemistry plays an important role as the first step of the study, as it allows establishing the presence of chemicals in the environment, estimate their concentration levels, identify sources and determine their degradation pathways. These tasks involve serious difficulties requiring different analytical solutions adjusted to purpose. Thus, the complexity of the matrices requires highly selective analytical methods; the large number and variety of compounds potentially present in the samples demands the application of wide scope methods; the low concentrations at which these contaminants are present in the samples require a high detection sensitivity, and high demands on the confirmation and high structural information are needed for the characterisation of unknowns. New developments on analytical instrumentation have been applied to solve these difficulties. Furthermore and not less important has been the development of new specific software packages intended for data acquisition and, in particular, for post-run analysis. Thus, the use of sophisticated software tools has allowed successful screening analysis, determining several hundreds of analytes, and assisted in the structural elucidation of unknown compounds in a timely manner.

Analytical improvements of hybrid LC-MS/MS techniques for the efficient evaluation of emerging contaminants in river waters: a case study of the Henares River (Madrid, Spain).

PURPOSE: Instrumental capabilities and software tools of modern hybrid mass spectrometry (MS) instruments such as high-resolution mass spectrometry (HRMS), quadrupole time-of-flight (QTOF), and quadrupole linear ion trap (QLIT) were experimentally investigated for the study of emerging contaminants in Henares River water samples. METHODS: Automated screening and confirmatory capabilities of QTOF working in full-scan MS and tandem MS (MS/MS) were explored when dealing with real samples. Investigations on the effect of sensitivity and resolution power influence on mass accuracy were studied for the correct assignment of the amoxicillin transformation product 5(R) amoxicillin-diketopiperazine-2',5' as an example of a nontarget compound. On the other hand, a comparison of quantitative and qualitative strategies based on direct injection analysis and off-line solid-phase extraction sample treatment were assayed using two different QLIT instruments for a selected group of emerging contaminants when operating in selected reaction monitoring (SRM) and information-dependent acquisition (IDA) modes. RESULTS AND DISCUSSION: Software-aided screening usually needs a further confirmatory step. Resolving power and MS/MS feature of QTOF showed to confirm/reject most findings in river water, although sensitivity-related limitations are usually found. Superior sensitivity of modern QLIT-MS/MS offered the possibility of direct injection analysis for proper quantitative study of a variety of contaminants, while it simultaneously reduced the matrix effect and increased the reliability of the results. Confirmation of ethylamphetamine, which lacks on a second SRM transition, was accomplished by using the IDA feature. CONCLUSION: Hybrid MS instruments equipped with high resolution and high sensitivity contributes to enlarge the scope of targeted analytes in river waters. However, in the tested instruments, there is a margin of improvement principally in required sensitivity and data treatment software tools devoted to reliable confirmation and improved automated data processing.

Determination of malachite green residues in fish using molecularly imprinted solid-phase extraction followed by liquid chromatography-linear ion trap mass spectrometry.

This paper describes the development of an analytical procedure to determine malachite green (MG) residues in salmon samples using molecularly imprinted polymers (MIPs) as the extraction and clean-up material, followed by liquid chromatography-linear ion trap mass spectrometry (LC-QqQLIT-MS/MS). MG and two structurally related compounds, crystal violet (CV) and brilliant green (BG) were employed for the selectivity test. The imprinted polymers exhibited high binding affinity for MG, while CV and BG showed less binding capacity: 47% and 34%, respectively. The recovery values of MG in salmon samples fortified with leucomalachite green (LMG) were determined by measuring the amount of MG in the sample, after carrying out the oxidation reaction with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), which converts the LMG back into chromic-form. The average recovery of MG in spiked salmon muscle over the concentration range 1-100 ng g(-1) was 98% with a relative standard deviation value (R.S.D.) below 12%. The method detection limits (MDLs) obtained for MG, CV, BG and their leuco-metabolites were in the range of 3-20 ng kg(-1) (ppt).

Application of passive sampling devices for screening of micro-pollutants in marine aquaculture using LC-MS/MS.

Knowledge on the presence of micro-pollutants, in particular emerging contaminants, such as pharmaceuticals, biocides or some pesticides, in semi-enclosed coastal areas, where fish farms are installed, is very limited. This article shows data on the presence of micro-pollutants over 1 year monitoring campaign carried out in a fish farm placed on the Mediterranean Sea. With this work, the results of the development of an analytical procedure which, makes use of passive sampling techniques (with polar organic chemical integrative samplers, POCIS, pharmaceutical configuration) and of the LC-QLIT-MS system, are presented. The development of the analytical procedure entail laboratory-based calibration with the samplers POCIS, for calculating uptake rates and sampling rates of compounds representative of a wide range of polarity (4.56>or=logK(ow)>or=-0.12). The uptake of the target compounds in the sampler POCIS, follows a linear pattern for most compounds, and sampling rates varied from 0.001 to 0.319l/d. The calibration experiments have shown that POCIS pharmaceutical configuration could be used for sampling other non-target compounds, such as pesticides and biocides with a logK(ow)

Determination of selected non-authorized insecticides in peppers by liquid chromatography time-of-flight mass spectrometry and tandem mass spectrometry.

In this work, two analytical methods based on liquid chromatography coupled to electrospray time-of-flight mass spectrometry (LC/ESI-TOFMS) and tandem mass spectrometry (LC/ESI-MS/MS) are described for the identification, confirmation and quantitation of three insecticides non-authorized in the European Union (nitenpyram, isocarbophos and isofenphos-methyl) but detected in recent monitoring programmes in pepper samples. The proposed methodologies involved a sample extraction procedure using liquid-liquid partition with acetonitrile followed by a cleanup step based on dispersive solid-phase extraction. Recovery studies performed on peppers spiked at different fortification levels (10 and 50 microg kg(-1)) yielded average recoveries in the range 76-100% with relative standard deviation (RSD) (%) values below 10%. Identification, confirmation and quantitation were carried out by LC/TOFMS and LC/MS/MS using a hybrid triple quadrupole linear ion trap (QqLIT) instrument in multiple-reaction monitoring (MRM) mode. The obtained limits of quantitation (LOQs) were in the range 0.1-5 microg kg(-1), depending on each individual technique. Finally, the proposed methods were successfully applied to the analysis of suspected pepper samples.