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1.
Environ Microbiol ; 24(11): 5105-5122, 2022 11.
Article in English | MEDLINE | ID: mdl-35799498

ABSTRACT

Thiabendazole (TBZ), is a persistent fungicide/anthelminthic and a serious environmental threat. We previously enriched a TBZ-degrading bacterial consortium and provided first evidence for a Sphingomonas involvement in TBZ transformation. Here, using a multi-omic approach combined with DNA-stable isotope probing (SIP) we verified the key degrading role of Sphingomonas and identify potential microbial interactions governing consortium functioning. SIP and amplicon sequencing analysis of the heavy and light DNA fraction of cultures grown on 13 C-labelled versus 12 C-TBZ showed that 66% of the 13 C-labelled TBZ was assimilated by Sphingomonas. Metagenomic analysis retrieved 18 metagenome-assembled genomes with the dominant belonging to Sphingomonas, Sinobacteriaceae, Bradyrhizobium, Filimonas and Hydrogenophaga. Meta-transcriptomics/-proteomics and non-target mass spectrometry suggested TBZ transformation by Sphingomonas via initial cleavage by a carbazole dioxygenase (car) to thiazole-4-carboxamidine (terminal compound) and catechol or a cleaved benzyl ring derivative, further transformed through an ortho-cleavage (cat) pathway. Microbial co-occurrence and gene expression networks suggested strong interactions between Sphingomonas and a Hydrogenophaga. The latter activated its cobalamin biosynthetic pathway and Sphingomonas its cobalamin salvage pathway to satisfy its B12 auxotrophy. Our findings indicate microbial interactions aligning with the 'black queen hypothesis' where Sphingomonas (detoxifier, B12 recipient) and Hydrogenophaga (B12 producer, enjoying detoxification) act as both helpers and beneficiaries.


Subject(s)
Dioxygenases , Fungicides, Industrial , Sphingomonas , Sphingomonas/genetics , Sphingomonas/metabolism , Thiabendazole/metabolism , Fungicides, Industrial/metabolism , Dioxygenases/metabolism , Biodegradation, Environmental , Bacteria/genetics , Bacteria/metabolism , Carbazoles/metabolism , Vitamin B 12/metabolism
2.
Sci Total Environ ; 819: 153063, 2022 May 01.
Article in English | MEDLINE | ID: mdl-35031361

ABSTRACT

The knowledge about the interaction of nanoplastics with other aquatic pollutants and their combined effects on biota is very scarce. In this work, we studied the interaction between polystyrene nanoplastics (PS NPs) (30 nm) and the micropollutants in a biologically treated wastewater effluent (WW). The capacity of PS NPs to sorb micropollutants was studied as well as their single and combined toxicity towards three freshwater organisms: the recombinant bioluminescent cyanobacterium, Anabaena sp. PCC 7120 CPB4337; the duckweed, Spirodela polyrhiza and the cladoceran, Daphnia magna. The endpoints were the inhibition of bioluminescence, the growth inhibition of the aquatic plant and the immobilization of D. magna after 24, 72 and 48 h of exposure, respectively. Combination Index (CI)-isobologram method was used to quantify mixture toxicity and the nature of interactions. PS NPs sorbed a variety of chemicals present in WW as micropollutants in a range of tens of ng/L to µg/L. It was found that those pollutants with positive charge were the main ones retained onto PS NPs, which was attributed to the electrostatic interaction with the negatively charged PS NPs. Regarding the toxicological effects, single exposure to PS NPs affected the three tested organisms. However, single exposure to WW only had a negative impact on the cyanobacterium and S. polyrhiza with no observed toxicity to D. magna. Regarding PS NPs-WW combined exposure, a reduction of toxicity in comparison with single exposure was observed probably due to the sorption of micropollutants onto PS NPs, which resulted in lower bioavailability of the micropollutants. In addition, the formation of PS NPs-WW heteroaggregates was observed which could result in lower bioavailability of PS NPs and sorbed micropollutants, thus lowering toxicity. This study represents a near-realistic scenario approach to the potential sorption of wastewater pollutants onto nanoplastics that could alter the toxicological effect on the biota.


Subject(s)
Nanoparticles , Water Pollutants, Chemical , Microplastics , Nanoparticles/toxicity , Polystyrenes/chemistry , Polystyrenes/toxicity , Wastewater , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/toxicity
3.
Water Res ; 203: 117532, 2021 Sep 15.
Article in English | MEDLINE | ID: mdl-34419922

ABSTRACT

In this study, a full cycle of agricultural reuse of agro-food wastewater (synthetic fresh-cut wastewater, SFCWW) at pilot plant scale has been investigated. Treated SFCWW by ozonation and two solar processes (H2O2/solar, Fe3+-EDDHA/H2O2/solar) was used to irrigate two raw-eaten crops (lettuce and radish) grown in peat. Two foodborne pathogens (E. coli O157:H7 and Salmonella enteritidis) and five organic microcontaminants (OMCs: atrazine, azoxystrobin, buprofezin, procymidone and terbutryn) were monitored along the whole process. The three studied processes showed a high treatment capability (reaching microbial loads < 7 CFU/100 mL and 21-90 % of OMC reduction), robustness (based on 7 or 10 analysed batches for each treatment process) and high suitability for subsequent treated SFCWW safe reuse: non-phytotoxic towards Lactuca sativa and no bacterial regrowth during its storage for a week. The analysis of the harvested crop samples irrigated with treated SFCWW in all the studied processes showed an absence of microbial contamination (< limit of detection, LOD; i.e., < 1 CFU/99 g of lettuce and < 1 CFU/8 g of radish), a significant reduction of OMC uptake (in the range 40-60 % and > 90 % for solar treated and ozonated SFCWW, respectively) and bioaccumulation in both crops in comparison with the results obtained with untreated SFCWW. Moreover, the chlorophyll content in the harvested lettuces irrigated with SFCWW treated by Fe3+-EDDHA/H2O2/solar was twice than that irrigated with SFCWW treated by H2O2/solar and ozone, indicating the additional advantage of using Fe3+-EDDHA as an iron source to reduce the risk of iron chlorosis in crops. Finally, the chemical (dietary risk assessment for the combined exposure of the 5 OMCs) and quantitative microbiological risk assessment (QMRA) of the harvested crops showed the capability of the studied processes to reduce the risk associated with untreated SFCWW reuse by more than 50 % and more than 4 orders of magnitude, respectively.


Subject(s)
Anemia, Hypochromic , Escherichia coli O157 , Ozone , Agricultural Irrigation , Hydrogen Peroxide , Lactuca , Wastewater
4.
Sci Total Environ ; 755(Pt 2): 142624, 2021 Feb 10.
Article in English | MEDLINE | ID: mdl-33045600

ABSTRACT

This work proposes the evaluation of an aluminized surface on the bottom of open reactors to perform a photo-Fenton process, at circumneutral pH (using Fe III-Ethylenediamine-N,N'-disuccinic acid complex), for elimination of micropollutants (MPs) in real effluents from municipal wastewater treatment plants (EMWWTP). Firstly, the strategy was to initially investigate the real EMWWTP spiked with several MPs (acetaminophen, diclofenac, carbamazepine, caffeine, trimethoprim and sulfamethoxazole) with 20 and 100 µg L-1 in a laboratory scale (evaluated by HPLC-UV) using a solar simulator. Finally, the removal of all MCs present in the real EMWWTP was monitored (evaluated by HPLC-MS) in a pilot-scale (90 L) in a raceway pond reactor (RPR). The treatment time required for degradation above 80% for the investigated MPs was over 30 min, and the predominant effect could be mainly associated with organics present in the real EMWWTP due to the light attenuation and scavenging of radical species. Moreover, the results confirmed that chloride and sulfate would most likely equally not affect the process. The use of an aluminized surface on the bottom of RPRs has been confirmed as a suitable option to improve the photo-Fenton reaction, enabling the use of lower doses of iron. Up to 60 different MPs found in EMWWTP have been successfully degraded using 0.1 mM of Fe at circumneutral pH with a consumption of 30 mg L-1 H2O2 with less than 45 min.

5.
Water Res ; 169: 115220, 2020 Feb 01.
Article in English | MEDLINE | ID: mdl-31677437

ABSTRACT

The effect of the UV-C/free chlorine (FC) process on the removal of contaminants of emerging concern (CECs) from real urban wastewater as well as the effect of UV-C radiation on the formation of trihalomethanes (THMs) compared to FC process alone was investigated. Unlike of FC process, UV-C/FC was really effective in the degradation of the target CECs (carbamazepine (CBZ), diclofenac, sulfamethoxazole and imidacloprid) in real wastewater (87% degradation of total CECs within 60 min, QUVC = 1.33 kJ L-1), being CBZ the most refractory one (49.5%, after 60 min). The UV-C radiation significantly affected the formation of THMs. THMs concentration (mainly chloroform) was lower in UV-C/FC process after 30 min treatment (<1 µgL-1 = limit of quantification (LOQ)) than in FC process in dark (2.3 µgL-1). Noteworthy, while in FC treated wastewater chloroform concentration increased after treatment, UV-C/FC process resulted in a significant decrease (residual concentrations below the LOQ), even after 24 h and 48 h post-treatment incubation. The formation of radicals due to UV-C/FC process can reduce THMs compared to chlorination process, because part of FC reacts with UV-C radiation to form radicals and it is no longer available to form THMs. These results are encouraging in terms of possible use of UV-C/FC process as advanced treatment of urban wastewater even for possible effluent reuse.


Subject(s)
Environmental Pollutants , Water Pollutants, Chemical , Water Purification , Chlorine , Disinfection , Halogenation , Trihalomethanes , Ultraviolet Rays , Wastewater
6.
J Agric Food Chem ; 67(25): 6930-6939, 2019 Jun 26.
Article in English | MEDLINE | ID: mdl-31150236

ABSTRACT

In many regions, reuse of reclaimed water (RW) is a necessity for irrigation. The presence of organic microcontaminants (OMCs) in RW and their translocation to plants may represent a risk of human exposure. Nevertheless, information available about real field crops is scarce and focused on a limited number of compounds. The novelty of this work relies on the application of a wider-scope analytical approach based on a multianalyte target analysis (60 compounds) and a suspect screening (>1300 compounds). This methodology was applied to real field-grown tomato crops irrigated with RW. The study revealed the presence of 17 OMCs in leaves (0.04-32 ng g-1) and 8 in fruits (0.01-1.1 ng g-1), 5 of them not reported before in real field samples. A health-risk assessment, based on the toxicological threshold concern (TTC) concept, showed that RW irrigation applied under the conditions given does not pose any threat to humans.


Subject(s)
Fruit/chemistry , Solanum lycopersicum/metabolism , Wastewater/analysis , Water Pollutants, Chemical/analysis , Agricultural Irrigation , Biological Transport , Fruit/metabolism , Humans , Solanum lycopersicum/chemistry , Plant Leaves/chemistry , Plant Leaves/metabolism , Risk Assessment , Water/chemistry , Water Pollutants, Chemical/metabolism
7.
Chemosphere ; 232: 152-163, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31154175

ABSTRACT

Agriculture is considered as the main source of water contamination by pesticides. However, food packaging or processing industries are also recognised as relevant point sources of contamination by these compounds, not yet investigated in depth. The objective of this work has been to improve current knowledge about the presence and concentration of pesticides in the effluent of a food processing industry, as well as to investigate their main transformation products (TPs). An analytical strategy combining target and suspect analysis has been applied to provide an evaluation of the effluents. The methodology involves solid-phase extraction (SPE) of wastewater samples followed by (i) liquid chromatography quadrupole-linear ion trap tandem mass spectrometry (LC-QqLIT-MS/MS) for quantitative target analysis and (ii) liquid chromatography coupled to quadrupole-time-of-flight high resolution mass spectrometry (LC-QTOF-HRMS) to identify non-target pesticides and possible TPs. The results revealed the presence of 17 of the target pesticides analysed and 3 additional ones as a result of the suspect screening performed by HRMS. The TPs were investigated for the pesticides found at the highest concentrations: imazalil (7038-19802 ng/L), pyrimethanil (744-9591 ng/L) and thiabendazole (341-926 ng/L). Up to 14 TPs could be tentatively identified, demonstrating the relevance of this type of studies. These data provide a better understanding of the occurrence of pesticides and their TPs in agro-food industrial effluents.


Subject(s)
Pesticides/analysis , Wastewater/chemistry , Water Pollutants, Chemical/analysis , Agriculture , Chromatography, Liquid/methods , Environmental Monitoring , Food Industry , Food-Processing Industry , Solid Phase Extraction , Tandem Mass Spectrometry/methods , Thiabendazole/analysis , Wastewater/analysis , Water Pollution, Chemical/statistics & numerical data
8.
J Chromatogr A ; 1507: 84-94, 2017 Jul 21.
Article in English | MEDLINE | ID: mdl-28583389

ABSTRACT

It is well known that wastewater treatment plant (WWTP) effluents usually contain micropollutants such as pharmaceuticals (or their transformation products, TPs) or pesticides, which is a major issue when evaluating their possible reuse (e.g. for irrigation in agriculture). In search for an improved accuracy and simplicity, methods based on the direct injection of the sample (DI) represent a recent trend taking advantage of the increasing sensitivity of new mass spectrometry (MS) instruments. Thus, the present study shows the development and validation of a DI-based method by ultra-high-performance liquid chromatography quadrupole-linear ion trap analyser (UHPLC-QqLIT-MS/MS). The proposed method was applied to the monitoring of 115 organic microcontaminants (including pharmaceuticals, TPs and pesticides) at the ngL-1/µgL-1 level in wastewater effluents from urban WWTPs. Sample pre-treatment was reduced to acetonitrile addition and filtration of the mixture previous to LC-MS analysis. Total analysis time was <15min. A subsequent validation protocol was carried out in treated WW (TWW), following indications of SANTE and Eurachem Guidelines. Linearity and matrix effect were evaluated in the range of 10-1000ngL-1. 70% of the analytes showed a moderate matrix effect (≤25%). Trueness (expressed as recovery) and precision (calculated as relative standard deviation, RSD) were evaluated at four concentration levels (20, 50, 500 and 1000ngL-1) in TWW samples. The LODs ranged from 1 to 357ngL-1 and the LOQs from 10 to 500ngL-1. 92% of the compounds showed limits of quantification ≤100ngL-1. In most cases, mean recoveries were in the range 70-120%, and RSD values were ≤20%. The validated method was successfully applied to the analysis of 10 TWW samples, demonstrating the occurrence of 67 target compounds at concentration levels from 26705ngL-1 (4-aminoantipyrine) to 10ngL-1 (tebuconazole and bezafibrate).


Subject(s)
Chromatography, High Pressure Liquid/methods , Pesticides/analysis , Tandem Mass Spectrometry/methods , Wastewater/analysis , Water Pollutants, Chemical/analysis , Chromatography, High Pressure Liquid/instrumentation , Limit of Detection , Pesticides/isolation & purification
9.
Food Chem ; 173: 607-18, 2015 Apr 15.
Article in English | MEDLINE | ID: mdl-25466066

ABSTRACT

A method has been developed and validated for the simultaneous detection and quantification of phytochemicals in nutraceutical products obtained from green tea. For that purpose, ultra-high performance liquid chromatography coupled to single-stage Orbitrap high resolution mass spectrometry (UHPLC-Orbitrap-MS) has been used. A database containing 37 compounds has been used for the detection and identification of the target compounds. The developed methodology was based on solid-liquid extraction, using a mixture of methanol:H2O (80:20, v/v, pH 4), followed by dilution (10 times) with a mixture of ammonium acetate:methanol (50:50, v/v). Chromatographic conditions were optimised and full scan accurate mass data acquisition using electrospray ionisation in positive and negative ion mode was used. Moreover, all-ion fragmentation mode was used to get information of fragment ions, and they were used for identification purposes. The developed method was validated, obtaining repeatability (intra-day) and inter-day precision values (expressed as relative standard deviation, RSD) lower than 16% and 20%, respectively. Lower limits were also evaluated and limits of detection (LODs) ranged from 1 to 50 µg L(-1), while limits of quantification (LOQs) ranged from 2 to 150 µg L(-1). Recovery was performed at five levels and it ranged from 70% to 109%. Finally, this method was used to evaluate the phytochemical content in 10 samples (tablets or capsules), showing concentrations of (+)-catechin, (-)-epicatechin, gallic acid, (-)-gallocatechin and quercetin-3-O-rutinoside, ranging from 258 (C6) to 10,729 (C6) mg kg(-1).


Subject(s)
Chromatography, High Pressure Liquid/methods , Dietary Supplements/analysis , Mass Spectrometry/methods , Phytochemicals/analysis , Tea/chemistry , Catechin/analogs & derivatives , Catechin/analysis , Gallic Acid/analysis , Glucosides , Limit of Detection , Quercetin/analogs & derivatives , Reproducibility of Results , Sensitivity and Specificity , Spectrometry, Mass, Electrospray Ionization
10.
J AOAC Int ; 97(4): 1027-33, 2014.
Article in English | MEDLINE | ID: mdl-25145133

ABSTRACT

A method for the determination of 14 biopesticides and piperonyl butoxide (PBO), often applied in organic farming, in vegetables and fruits has been developed. Extraction was performed using the Quick, Easy, Cheap, Effective, Rugged, and Safe method, and the determination was carried out by ultra-performance LC/MS/MS in 9 min. Several different food commodities were evaluated as representative matrixes, namely, cucumber, tomato, pepper (high water content), and strawberry and orange (high acid and water content). Biopesticides were quantified using matrix-matched calibration, and the optimized method was validated at three concentration levels, i.e., 10, 50, and 100 microg/kg, for all the compounds, yielding recoveries in the range 70-112%, 71-112%, and 70-109%, respectively, with RSDs <28%. LOQs were <3 microg/kg for all biopesticides. The validated procedure was applied to the analysis of vegetables and fruits, including products from organic farming; PBO was detected in one sample at 8 microg/kg.


Subject(s)
Fruit/chemistry , Pesticides/analysis , Solid Phase Extraction , Vegetables/chemistry , Chromatography, High Pressure Liquid , Tandem Mass Spectrometry
11.
Int J Food Sci Nutr ; 65(7): 791-6, 2014 Nov.
Article in English | MEDLINE | ID: mdl-24828257

ABSTRACT

Phytochemicals content, including several families such as phenolic acids, isoflavones, flavones, flavonols, isothiocyanates, and glucosinolates, was determined in pre-cooked convenience vegetables by ultra high performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS). It was observed that there is not a common behavior of the individual concentration of phytochemicals during the lifetime and cooking of the matrix, and compounds change their concentration without a specific trend. It was observed that neither lifetime nor cooking process have significant effects on the total content of phytochemicals except in broccoli, although some changes in the individual content of the target compounds were observed, suggesting that interconversion processes could be performed during the lifetime and/or cooking process of the product.


Subject(s)
Cooking , Food Analysis/methods , Phytochemicals , Vegetables/chemistry , Food Storage , Time Factors
12.
J Am Soc Mass Spectrom ; 25(5): 899-902, 2014 May.
Article in English | MEDLINE | ID: mdl-24658807

ABSTRACT

A method based on gas chromatography-atmospheric pressure chemical ionization-mass spectrometry (GC-APCI-MS) has been developed for the analysis of pesticides in meat by using quadrupole-time of flight mass spectrometry (QTOF-MS). Ionization and MS conditions were studied for 71 compounds, although only 51 showed acceptable performance. The protonated form of the analytes was mainly found ([M + H]⁺), although some compounds generated the molecular ion (M⁺(•)). A fast and generic extraction procedure was applied in sample pretreatment. The analytical method was suitable for qualitative analysis, and it was also evaluated for quantitative analysis, obtaining adequate recovery and precision values for most of the studied analytes at two concentration levels (50 and 150 µg/kg). Several operational drawbacks were found with this instrument, such as slow stabilization and moderate sensitivity, although the fast switching between LC and GC allows the increase of its applicability.


Subject(s)
Dietary Fats/analysis , Food Inspection/methods , Meat/analysis , Pesticide Residues/analysis , Animals , Atmospheric Pressure , Cattle , Chickens , Food Contamination , Gas Chromatography-Mass Spectrometry , Meat/economics , Models, Statistical , Molecular Structure , Molecular Weight , Pesticide Residues/chemistry , Reproducibility of Results , Spain , Sus scrofa
13.
J Sep Sci ; 37(6): 665-74, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24532456

ABSTRACT

A method based on QuEChERS (quick, easy, cheap, effective, rugged, and safe) has been developed and validated for the determination and quantification of more than 140 pesticides in nutraceutical products obtained from green tea (Camellia sinensis). Extraction was performed with acidified acetonitrile (acetic acid 1%, v/v) and a clean-up step using primary secondary amine (50 mg), graphitized black carbon (100 mg) and magnesium sulfate (200 mg) was needed. Pesticide determination was achieved utilizing GC coupled to triple quadrupole MS/MS using the selective-reaction monitoring mode. The total run time was 23 min. Pesticides were quantified using matrix-matched calibration. Recoveries ranged from 70 to 120% and relative SD was lower than 25% at 10, 50, and 100 µg/kg. LOQs were lower than 10 µg/kg. 148 pesticides were validated. The validated method was applied to commercial nutraceutical products, detecting 4,4-dichlorobenzophenone (28 µg/kg), o,p'-dicofol (38 µg/kg) and p,p-dicofol (44 µg/kg) in a few samples.


Subject(s)
Camellia sinensis/chemistry , Dietary Supplements/analysis , Food Contamination/analysis , Pesticides/analysis , Gas Chromatography-Mass Spectrometry
14.
J Mass Spectrom ; 49(1): 27-36, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24446260

ABSTRACT

A multiresidue and multiclass method for the simultaneous determination of more than 350 compounds including pesticides, biopesticides and veterinary drugs in different meat matrices (beef, pork and chicken) by ultra-high performance liquid chromatography coupled to Orbitrap MS has been developed. In the present study, the determination of fragments was accomplished as an essential tool for a reliable identification of compounds using high resolution MS. To obtain these fragments, different strategies have been carried out in order to ensure an appropriate fragment assignment and identification. The analytical method is suitable for qualitative analysis, and it was also evaluated for quantitative analysis. Generic extraction conditions were optimized, obtaining adequate recovery and precision values for most of the studied analytes (>290). The limits of detection ranged from 2 to 16 µg kg(-1). Limits of quantification were 10 µg kg(-1) with the exception of few compounds with a higher value (50 or 100 µg kg(-1)). Limits of identification were also established, and they ranged from 2 to 150 µg kg(-1). This method was applied to the analysis of 18 meat samples and some veterinary drugs as enrofloxacin and sulfadiazine were detected and further identified/quantified (with triple quadrupole) in two different samples at 33 µg kg(-1) and trace levels, respectively. No pesticides were detected in the analyzed samples.


Subject(s)
Drug Residues/analysis , Mass Spectrometry/methods , Meat/analysis , Pesticide Residues/analysis , Veterinary Drugs/analysis , Animals , Cattle , Chickens , Drug Residues/chemistry , Mass Spectrometry/instrumentation , Pesticide Residues/chemistry , Reproducibility of Results , Sensitivity and Specificity , Swine , Veterinary Drugs/chemistry
15.
Talanta ; 118: 277-91, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24274299

ABSTRACT

A review of sample preparation and analytical techniques currently used to analyze pesticides in nutraceutical products is shown. Different sample treatments are commented, and the QuEChERS method is the most used (quick, easy, cheap, effective, rugged and safe). For the chromatographic determination, gas chromatography (GC) and liquid chromatography (LC) are evaluated. Different detection modes are discussed, and simple quadrupole mass spectrometry (Q-MS) and triple quadrupole tandem mass spectrometry (QqQ-MS/MS) are the most used. Finally, a review of the occurrence of pesticides (from the revised literature) in real samples is presented, evaluating several matrices, such as nutraceuticals, dietary supplements, medicinal plants, and fish oil. The occurrence of several pesticides was reported: γ-HCH (lindane), endosulfan, procymidone, azoxystrobin, p,p'-DDE, metalaxyl, quintozene, tolclofos-methyl, chlorpyrifos and hexachlorobenzene.


Subject(s)
Dietary Supplements/analysis , Food Contamination/analysis , Gas Chromatography-Mass Spectrometry/methods , Pesticide Residues/analysis , Humans
16.
J Sep Sci ; 37(1-2): 69-76, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24302622

ABSTRACT

The analysis of brominated flame retardants, such as polybrominated diphenyl ethers (PBDEs), has received increased interest because of their toxicity and ubiquity. According to European Union Directive 2008/105/EC, the development of highly sensitive and selective methods capable of determining PBDEs at low concentration levels (<0.5 ng/L) is necessary. In this work, an SPE method was developed for the analysis of the six PBDEs (BDE-28, BDE-47, BDE-99, BDE-100, BDE-153, BDE-154) specified by the aforementioned directive in surface waters. The analyses were performed by GC coupled to magnetic sector high-resolution MS. The conditions were also optimized to detect the target compounds in water samples at concentrations below the environmental quality standards established by European legislation. The validated method provided adequate linearity (determination coefficient, R(2) ≥ 0.9960), recovery (101-120%, except for BDE-47 at 5 ng/L, 127%), and precision values (RSD < 20%) at two fortification levels (0.2 and 5 ng/L). The method showed LODs and LOQs ranging from 0.02 to 0.05 and from 0.05 to 0.1 ng/L, respectively. The method was applied in surface water samples, allowing the determination of these compounds at the limits established by current legislation.


Subject(s)
Environmental Monitoring/methods , Flame Retardants/analysis , Fresh Water/chemistry , Gas Chromatography-Mass Spectrometry/methods , Halogenated Diphenyl Ethers/analysis , Water Pollutants, Chemical/analysis , Water Pollution, Chemical/legislation & jurisprudence , Environmental Monitoring/legislation & jurisprudence , European Union , Sensitivity and Specificity , Water Pollution, Chemical/analysis
17.
Environ Sci Process Impacts ; 15(12): 2194-203, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24141237

ABSTRACT

A comprehensive survey of the occurrence of organic compounds in 30 wastewater (WW) effluent samples from 21 urban wastewater treatment plants (WWTPs) from both secondary and tertiary treatments was carried out in the Mediterranean and Atlantic basins of the Andalusia region (south of Spain). For each sample, a total of 226 compounds including pesticides and some transformation products, polycyclic aromatic hydrocarbons (PAHs), phenolic compounds and volatile organic compounds (VOCs) were monitored with the aim of evaluating their occurrence in urban WW effluents. Compounds belonging to each class were detected. Among pesticides, insecticides such as clorfenvinphos and diazinon as well as herbicides such as diuron, sebuthylazine, terbuthylazine and terbuthylazine desethyl were the most frequently detected. The ubiquity of some compounds such as fluorene, phenanthrene and pyrene was also demonstrated. The compounds evaluated were detected at low concentrations (in general below 1 µg L(-1)), except 4-tert-octylphenol, which was detected at extremely high concentrations (up to 443 µg L(-1)). PAHs and VOCs were the compounds most frequently detected in the assayed samples, and they are the main sources of contamination in WWTPs, as well as some herbicides and transformation products.


Subject(s)
Organic Chemicals/analysis , Wastewater/analysis , Water Pollutants, Chemical/analysis , Atlantic Ocean , Mediterranean Sea , Multivariate Analysis , Pesticides/analysis , Risk Assessment , Spain
18.
Anal Bioanal Chem ; 405(20): 6543-53, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23712649

ABSTRACT

A fast and generic method has been developed for the simultaneous monitoring of >250 pesticides and veterinary drugs (VDs) in animal feed. A 'dilute-and-shoot' extraction with water and acetonitrile (1% formic acid) followed by a clean-up step with Florisil cartridges was applied. The extracts were analysed by ultra-high performance liquid chromatography coupled to hybrid analyser quadrupole-time-of-flight mass spectrometry using both positive and negative electrospray ionisation. The detection of the residues was accomplished by retention time and accurate mass using an in-house database. The identification of the detected compounds was carried out by searching of fragment ions for each compound and isotopic pattern. The optimised method was validated and recoveries ranged from 60% to 120% at three concentrations (10, 50 and 100 µg kg(-1)) for 30%, 68% and 80% of compounds, respectively, included in the database (364) in chicken feed. Document SANCO 12495/2011 and Directive 2002/657/CE were used as guidelines for method validation. Intra-day and inter-day precisions, expressed as relative standard deviations, were lower than 20% for more than 90% of compounds. The limits of quantification ranged from 4 to 200 µg kg(-1) for most analytes, which are sufficient to verify compliance of products with legal tolerances. The applicability of the procedure was further tested on different types of feed (chicken, hen, rabbit and horse feed), evaluating recoveries and repeatability. Finally, the method was applied to the analysis of 18 feed samples, detecting some VDs (sulfadiazine, trimethoprim, robenidin and monensin Na) and only one pesticide (chlorpyrifos).


Subject(s)
Animal Feed/analysis , Chromatography, Liquid/methods , Drug Residues/chemistry , Pesticide Residues/chemistry , Pesticides/chemistry , Veterinary Drugs/chemistry , Mass Spectrometry/methods , Reproducibility of Results
19.
Sci Total Environ ; 447: 381-9, 2013 Mar 01.
Article in English | MEDLINE | ID: mdl-23410859

ABSTRACT

The occurrence of priority organic pollutants in wastewater (WW) effluents was evaluated in a semi-arid area, characterized by a high agricultural and tourism activity, as Almeria province (Southeastern Spain). Twelve wastewater treatment plants (WWTPs) were sampled in three campaigns during 2011, obtaining a total of 33 WW samples, monitoring 226 compounds, including pesticides, polycyclic aromatic hydrocarbons (PAHs), phenolic compounds and volatile organic compounds (VOCs). Certain banned organochlorine pesticides such as aldrin, pentachlorobenzene, o,p'-DDD and endosulfan lactone were found, and the most frequently detected pesticides were herbicides (diuron, triazines). PAHs and VOCs were also detected, noting that some of these pollutants were ubiquitous. Regarding phenolic compounds, 4-tertoctylphenol was found in all the WW samples at high concentration levels (up to 89.7 µg/L). Furthermore, it was observed that WW effluent samples were less contaminated in the second and third sampling periods, which corresponded to dry season. This evaluation revealed that despite the WW was treated in the WWTP, organic contaminants are still being detected in WW effluents and therefore they are released into the environment. Finally the risk of environmental threat due to the presence of some compounds in WWTP effluents, especially concerning 4-tertoctylphenol must be indicated.


Subject(s)
Pesticides/analysis , Polycyclic Aromatic Hydrocarbons/analysis , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/analysis , Agriculture , Aldrin/analysis , Chlorobenzenes/analysis , Dichlorodiphenyldichloroethane/analysis , Endosulfan/analysis , Environmental Monitoring , Spain , Volatile Organic Compounds/analysis
20.
J Agric Food Chem ; 61(4): 829-39, 2013 Jan 30.
Article in English | MEDLINE | ID: mdl-23282367

ABSTRACT

A simple and rapid method is described for the determination of veterinary drug (VD) residues in honey samples using turbulent flow chromatography coupled to ultrahigh-performance liquid chromatography-Orbitrap mass spectrometry (TFC-UHPLC-Orbitrap-MS). Honey samples were diluted with an aqueous solution of Na(2)EDTA (0.1 M). Then, they were injected into the chromatographic system including a TFC column. Afterward, the analytes were transferred to an UHPLC analytical column, where they were determined by UHPLC-Orbitrap-MS. Mean recoveries were obtained at three concentration levels (5, 10, and 50 µg/kg), ranging from 68 to 121% for most compounds. Repeatability (intraday precision) and interday precision (expressed as relative standard deviation, RSD) were <25% for most compounds. Limits of quantification (LOQs) ranged from 5 to 50 µg/kg and limits of identification (LOIs) from 0.1 to 50 µg/kg. The developed method was applied in honey samples, and it was fast and nonlaborious.


Subject(s)
Chromatography, High Pressure Liquid/methods , Chromatography, Liquid/methods , Drug Residues/analysis , Honey/analysis , Mass Spectrometry/methods , Veterinary Drugs/analysis , Food Contamination/analysis
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