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1.
Anal Bioanal Chem ; 411(27): 7281-7291, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31608426

RESUMO

The composition of Atlantic salmon feed has changed considerably over the last two decades from being marine-based (fishmeal and fish oil) to mainly containing plant ingredients. Consequently, concern related to traditional persistent contaminants typically associated with fish-based feed has been replaced by other potential contaminants not previously associated with salmon farming. This is the case for many pesticides, which are used worldwide to increase food production, and may be present in plant ingredients. Earlier studies have identified two organophosphorus pesticides, chlorpyrifos-methyl and pirimiphos-methyl, in plant ingredients used for aquafeed production. In the present study, we developed a reliable and sensitive analytical method, based on liquid chromatography coupled to tandem mass spectrometry, for the determination of these pesticides and their main metabolites in warm water (zebrafish) and cold water (Atlantic salmon) species, where possible differences in metabolites could be expected. The method was tested in whole zebrafish and in different salmon tissues, such as muscle, bile, kidney, fat, and liver. The final objective of this work was to assess kinetics of chlorpyrifos-methyl and pirimiphos-methyl and their main metabolites in fish tissue, in order to fill the knowledge gaps on these metabolites in fish tissues when fed over prolonged time.


Assuntos
Ração Animal/análise , Clorpirifos/análogos & derivados , Compostos Organotiofosforados/análise , Praguicidas/análise , Salmão/metabolismo , Peixe-Zebra/metabolismo , Animais , Clorpirifos/análise , Clorpirifos/metabolismo , Cromatografia Líquida de Alta Pressão , Pesqueiros , Limite de Detecção , Compostos Organotiofosforados/metabolismo , Praguicidas/metabolismo , Plantas/química , Alimentos Marinhos/análise , Espectrometria de Massas em Tandem
2.
Anal Bioanal Chem ; 411(27): 7187-7196, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31620825

RESUMO

Surface-enhanced Raman spectroscopy (SERS) has the potential to detect pesticide residues in agricultural products. However, some systemic pesticides, such as chlorpyrifos, can enter the plant tissue, and not just stay on the surface. Consequently, many SERS studies halted at practical application because of its complexity. In this work, SERS technology was used to detect chlorpyrifos residues in tea products at the semiquantitative level. A simple pretreatment method effectively avoided interference of other fluorescent substances, and all major peaks could be distinguished on the basis of a novel substrate. A principal component analysis algorithm was applied to form a regression model, and a nanogram detection limit was obtained. Furthermore, chlorpyrifos residues in the same tea products were also measured by gas chromatography-mass spectrometry, and the results show a small range of errors. From the comparative study of the two detection methods, the results suggest the great promise of SERS technology for rapid inspection of agricultural products.


Assuntos
Clorpirifos/análise , Resíduos de Praguicidas/análise , Análise Espectral Raman/métodos , Chá/química , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Praguicidas/análise
3.
J Agric Food Chem ; 67(45): 12341-12347, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31635458

RESUMO

Surface-enhanced Raman spectroscopy (SERS) can be used for the detection of trace amounts of pesticides in foods to ensure consumer safety. In this perspective, we highlight the trends of SERS-based assays in pesticide detection and the various challenges associated with their selectivity, reproducibility, and nonspecific binding. We also discuss and compare the target analyte capture techniques, such as the use of antibodies, aptamers, and molecularly imprinted polymers (MIPs), coupled with SERS to overcome the drawbacks as mentioned above. In addition, issues related to the nonspecific binding of analytes and its potential solution are discussed.


Assuntos
Praguicidas/análise , Análise Espectral Raman/métodos , Reprodutibilidade dos Testes , Análise Espectral Raman/instrumentação
4.
Sci Total Environ ; 692: 952-965, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31539999

RESUMO

The European Directive 98/83/CE legislates the presence of pesticides in drinking water, but apart from a few compounds, nothing is said about which pesticides should be monitored. Nevertheless, water companies need to go beyond the accomplishment of the legislation and find out pesticide contamination in all sources of water in order to manage the hazard assessment, and to guarantee safe drinking water to all the population. The aim of this work was to develop an analytical multi-residue method for circa 100 compounds. The method analyses previously monitored compounds in Barcelona city and its metropolitan area, as well as many emerging pesticides and some transformation products. An on-line sample extraction (0.75 mL) coupled to fast UHPLC-MS/MS method was developed. Good linearity (r2 > 0.995, with less residuals than 15%), accuracies and precisions under 25%, and acceptable expanded uncertainties were obtained for most of the monitored compounds, according to ISO/IEC 17025, obtaining limits of quantification between 5 and 25 ng/L for all compounds. A monitoring campaign on natural and treated waters in the Barcelona metropolitan area was carried out during 2016-2017. Results showed that pesticide contamination at the low stretch of Llobregat River and in its aquifer is severe. The maximum concentrations were in the range of few µg/L for carbendazim, DEET, diuron and propiconazole, and in the range 0.1-0.5 µg/L for bentazone, imidacloprid, isoproturon, simazine, metazachlor, methomyl, terbutryn and tebuconazole. However, the efficiency of advanced treatments in the DWTPs involved in drinking water production in the Barcelona metropolitan area allows the complete removal of pesticides and a safe water production for consumers. The method shows a good analytical performance for most compounds with a fast sample preparation and analysis. In addition, it has updated the knowledge about the occurrence of pesticides in the Barcelona city area.


Assuntos
Água Potável/química , Monitoramento Ambiental , Água Doce/química , Praguicidas/análise , Poluentes Químicos da Água/análise , Espanha
5.
Chemosphere ; 234: 925-930, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31519101

RESUMO

Organophosphate esters (OPEs), novel flame retardants (NFRs) and organochlorine pesticides (OCPs) are volatile to semi-volatile chemicals and therefore susceptible to approach equilibrium during typical deployments of polyurethane foam (PUF) disk passive air samplers. A generator column approach was used to measure the PUF-air partitioning coefficient (KPUF-air) for these targeted chemicals. KPUF-air values are required for these chemicals to estimate sampled equivalent air volumes, which vary substantially with temperature. Log KPUF-air measurements were made at temperatures ranging from +6 to +35 °C and resulting values ranged from 5.14 to 7.77. Enthalpies of phase change for PUF to air (ΔHPUF-air, kJ/mol) ranged from 51.3 to 98.9. Two relationships of log KPUF-air versus log Koctanol-air (KOA) were derived, grouping OPEs and NFRs separately. The relationship for NFRs was in fair agreement (within about 0.6 log units) to a long-standing relationship by Shoeib and Harner (since 2002) for polychlorinated biphenyls (PCBs). However, the estimated values using Shoeib-Harner relationship substantially underestimates KPUF-air for the OPEs than directly measured values (by about an order of magnitude). These findings highlight the importance of the direct measurements of KPUF-air for emerging classes of chemicals whose concentrations are at risk of equilibrating in PUF disk samplers.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Poliuretanos/química , Retardadores de Chama/análise , Hidrocarbonetos Clorados/análise , Organofosfatos , Praguicidas/análise , Bifenilos Policlorados , Poliuretanos/análise , Temperatura Ambiente
6.
Forensic Sci Int ; 302: 109936, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31493923

RESUMO

Stomach content is a matrix often applied in post-mortem cases. It is especially important in oral intoxication cases. The main advantages are the usually high concentration of analytes and the lack of biotransformation process. Still, even with extensive sample preparation, the final extract is not always suitable for analysis. The aim of this study was to develop an alternative method using QuEChERS for the extraction of drugs and pesticides from postmortem stomach content. Sample preparation started acetonitrile with 1% of acetic acid and QuEChERS salts. Later, the initial extract was cleaned-up using the EMR-Lipid sorbent. Residual water was withdrawn with MgSO4/NaCl in the third step and a final step with MgSO4. Vigorous shaken and centrifugation was performed after each step. The final supernatant was evaporated, re-suspended, and injected into GC-MS in full scan mode. This approach was successfully applied to stomach content, resulting in clean extracts, with low lipid levels. The method was able to detected target drugs and pesticides (cocaine, tramadol, diazepam, amytriptiline, phenobarbital, prochloraz, diazinon, heptachlor, permethrin, malathion and carbaryl) at the limit of detection of 0.1 mg/g or 0.1 mg/L. Recovery was over 70% for the majority of analytes, precision and accuracy was within acceptable range. The method was also applied to real forensic cases and carbofuran, terbuphos and fluoxetine was detected likewise. This work demonstrates that this method can provide an effective clean-up in high lipids samples such as stomach content, and can be used to analyze of pesticides and drugs in forensic cases.


Assuntos
Toxicologia Forense/métodos , Conteúdo Gastrointestinal/química , Ácido Acético , Acetonitrilos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Sulfato de Magnésio , Entorpecentes/análise , Praguicidas/análise , Preparações Farmacêuticas/análise , Acetato de Sódio , Cloreto de Sódio
7.
Chemosphere ; 235: 959-968, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31561312

RESUMO

Perfluoroalkyl substances (PFAS) and organochlorine pesticides (OCPs) in surface sediments were investigated from the Bering Sea, the Chukchi Sea and adjacent Arctic Ocean in 2010. Total concentrations (dry weight) of Σ14PFAS in surface sediments (0.85 ±â€¯0.22 ng g-1) of the Bering Sea were lower than that in the Chukchi Sea and adjacent Arctic Ocean (1.27 ±â€¯0.53 ng g-1). Perfluoro-butanoic acid (PFBS) and perfluoro-octanoic acid (PFOA) were the dominant PFAS in these areas. The concentrations of Σ15OCPs in the sediment of the Bering Sea (13.00 ±â€¯6.17 ng g-1) was slightly higher than that in the Chukchi and Arctic Ocean (12.05 ±â€¯2.27 ng g-1). The most abundant OCPs were hexachlorocyclohexane isomers (HCHs) and dichlorodiphenyltrichloroethane (DDT) and its metabolites. The composition patterns of HCHs and DDTs indicated that they were mainly derived from the early residues via river runoff. Increasing trends of PFAS, HCHs and DDTs in surface sediments from the Bering Sea to the Arctic Ocean were found, indicating oceanic transport. In summary, the concentrations of OCPs were orders of magnitude greater than the observed PFAS concentrations, and the concentrations of PFAS and OCPs in surface sediments from the Bering Sea to the Chukchi Sea and adjacent Arctic Ocean are at the low to moderate levels by comparing with other coastal and marine sediments worldwide.


Assuntos
DDT/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Hexaclorocicloexano/análise , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Poluentes Químicos da Água/análise , Regiões Árticas , China , DDT/química , Sedimentos Geológicos/química , Hexaclorocicloexano/química , Hidrocarbonetos Clorados/química , Oceanos e Mares , Praguicidas/química , Poluentes Químicos da Água/química
8.
Environ Monit Assess ; 191(10): 601, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31478100

RESUMO

The presence of organic compounds in drinking water is well recognized in many developing countries; however, the occurrence of organic contaminants in the groundwater of Saudi Arabia, which is the main source of drinking water in the country, is not well documented. A national comprehensive study was carried out to assess the occurrence of organic compounds in groundwater wells used for drinking water purpose, in different regions of Saudi Arabia. A total of 993 well water samples were collected from all 13 administrative regions of the kingdom. Samples were analyzed for a total of 131 organic compounds using the standard methods. The results indicated that total organic carbon values were in the range of 0.01 to 84.13 mg/L with an average weighted value of 12.61 mg/L. Organic compounds were detected in only 9 regions, with 19.84% of the samples containing organic compounds. Only 96 wells (9.67%) showed contents of organic compounds above the safe limits. Pesticides were not detected in any of the well water samples. Overall, organic compounds were found in only 197 out of 993 wells (19.84%) in the whole country. Most of the wells containing organic compounds were located in residential, industrial, and agriculture areas. Riyadh region and Eastern Province were found to have the most affected wells as compared to other regions. Several regions did not show any organic compounds in the well waters.It can be said that the problem of groundwater contamination with organic compounds in Saudi Arabia is not acute and is manageable at present. It is, however, recommended that a regular monitoring of drinking water wells of all regions should be carried out by the competent authorities for organic compounds to know any contamination if and when it happens. Preventing such contaminants from reaching drinking water sources and protecting drinking water well heads from such contaminants remains a priority.


Assuntos
Monitoramento Ambiental , Água Subterrânea/química , Compostos Orgânicos/análise , Poluentes Químicos da Água/análise , Água Potável/normas , Praguicidas/análise , Arábia Saudita
9.
J Agric Food Chem ; 67(40): 11244-11255, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31532667

RESUMO

Evaluation of acetylcholinesterase (AChE) activity and determination of organophosphorus pesticides (OPs) are of great importance for the clinical diagnosis of several serious diseases correlated with their variations in human blood serum. In this study, a highly selective and sensitive ratiometric fluorescent probe was innovatively fabricated for the evaluation of AChE activity and the determination of OPs in tap water and food on the basis of the inner filter effect (IFE) between nitrogen-doped carbon dots (N-CDs) and 2,3-diaminophenazine (DAP). N-CDs were synthesized via a one-pot hydrothermal method by using pancreatin and 1,2-ethanediamine as precursors. N-CDs showed excellent fluorescence properties and negligible cytotoxicity on human cervical carcinoma HeLa cells and human embryonic kidney 293T cells, suggesting their further biological applications. Upon the addition of AChE and choline oxidase, acetylcholine was catalyzed to produce choline that was further oxidized to produce H2O2. In the presence of horseradish peroxidase, o-phenylenediamine reacted with H2O2 to produce fluorescent DAP. Therefore, a ratiometric fluorescent probing platform existed via IFE between N-CDs with a fluorescence signal at 450 nm and DAP with a fluorescence signal at 574 nm. OPs irreversibly impeded the catalytic activity of AChE, finally leading to the decrease of DAP amount and the variation of ratiometric fluorescent signal. Under optimal conditions, such a fluorescent probe showed relatively low detection limits of 0.38 U/L for AChE, 3.2 ppb for dichlorvos, and 13 ppb for methyl-parathion. Practical application of this ratiometric fluorescent probe to detect OPs was further verified in tap water and food samples with satisfying results that were highly consisted with the results obtained by GC-MS.


Assuntos
Acetilcolinesterase/química , Técnicas Biossensoriais/métodos , Carbono/química , Corantes Fluorescentes/química , Contaminação de Alimentos/análise , Compostos Organofosforados/análise , Praguicidas/análise , Poluentes Químicos da Água/análise , Fluorescência , Água Doce/análise , Células HeLa , Humanos , Limite de Detecção , Pontos Quânticos/química
10.
J Environ Sci (China) ; 85: 82-93, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31471034

RESUMO

Cannabis is increasingly used for both medicinal and recreational purposes with an estimate of over 180 million users annually. Canada has recently legalized cannabis use in October 2018, joining several states in the United States of America (e.g., Colorado, California, and Oregon) and a few other countries. A variety of cannabis products including dry flowers, edibles, and oil products are widely consumed. With high demand for cannabis products worldwide, the quality of cannabis and its related products has become a major concern for consumer safety. Various guidelines have been set by different countries to ensure the quality, safety, and efficacy of cannabis products. In general, these guidelines require control of contaminants including pesticides, toxic elements, mycotoxins, and pathogens, as well as residual solvents in regard to cannabis oil. Accordingly, appropriate analytical methods are required to determine these contaminants in cannabis products for quality control. In this review, we focus on the current analytical challenges and method development for detection of pesticides and toxic elements in cannabis to meet various guidelines.


Assuntos
Cannabis/química , Poluentes Ambientais/análise , Praguicidas/análise , Oligoelementos/análise , Estados Unidos
11.
Environ Monit Assess ; 191(9): 599, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31463725

RESUMO

Pesticide contamination of groundwater is a common critical problem faced by many countries due to excessive and unconscious applications. As a result of increasing concerns about pesticides, several qualitative and quantitative risk assessment models/indicators were developed and applied. In this study, a practical approach was presented for the protection of groundwater from pesticide contamination. The first phase is the assessment of the specific vulnerability of groundwater to pesticide contamination using the DRASTIC-Pesticide model. The second phase is the monitoring and assessment of groundwater quality to verify vulnerability assessment. The third phase is to assess the impacts of pesticides on the environment and human health using a commonly applied pesticide risk indicator, the environmental impact quotient (EIQ). The pilot study area (PSA) is the Altinova region at Antalya city of Turkey which exhibits intensive agricultural activities and covers an approximate surface area of 75 km2. A total of 25 groundwater wells were chosen for monitoring of groundwater quality where four sessions of seasonal field measurements were conducted for 1 year. Two sessions of water quality analyses were also performed for many physical, bacteriological, and chemical parameters, including pesticides. Additionally, soil samples were analyzed, site surveys were conducted, and other relevant information (topographical, geological and meteorological characteristics, pesticide use and toxicological data sets, etc.) was gathered. The PSA was determined to have high vulnerability to contamination of groundwater, and it was verified through monitoring results. The commonly used pesticides in the PSA were ranked according to their risks to select pesticides with the least environmental impacts.


Assuntos
Água Potável/química , Meio Ambiente , Monitoramento Ambiental/métodos , Água Subterrânea/química , Praguicidas/análise , Poluentes Químicos da Água/análise , Agricultura/métodos , Humanos , Projetos Piloto , Medição de Risco , Turquia , Qualidade da Água
12.
Bioelectrochemistry ; 130: 107348, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31437810

RESUMO

A practical electrochemical biosensor with high sensitivity was developed for detecting organophosphorus (OP). Initially, Ce metal was introduced into an UiO-66-template to form Ce/UiO-66. Later, graphene oxide (GO), carbon black (CB) and multi-walled carbon nanotubes (MWCNTs) were separately added to Ce/UiO-66 to compare the effect of different carbon-based material types on the performance of the biosensor. Exclusively, Ce/UiO-66/MWCNTs with a Ce (7%) and MWCNT (30%) matrix was found to not only load more acetylcholinesterase (AChE) onto vacant sites but also increase electron transfer and decrease the number of diffusion pathways between the thiocholine and electrode surface. Moreover, the appropriate oxophilicity of Ce coupled with the high surface area and good conductivity of MWCNTs in the UiO-66 structure revealed a high affinity to acetylthiocholine chloride (ATCl) and possible catalysis of the hydrolysis of ATCl with a Michaelis-Menten constant of 0.258 mM. This biosensor, under optimal conditions, demonstrated a rapid and sensitive detection of paraoxon over a wide linear range of 0.01-150 nM, with a low detection limit of 0.004 nM. As a result, the AChE/Ce/UiO-66/MWCNTs/GCE biosensor can be employed in laboratory and field experiments to determine paraoxon levels.


Assuntos
Técnicas Biossensoriais/métodos , Cério/química , Estruturas Metalorgânicas/química , Paraoxon/análise , Praguicidas/análise , Acetilcolinesterase/química , Animais , Brassica/química , Electrophorus , Enzimas Imobilizadas/química , Proteínas de Peixes/química , Grafite/química , Modelos Moleculares , Nanotubos de Carbono/química , Spinacia oleracea/química
13.
Phys Chem Chem Phys ; 21(35): 19288-19297, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31451821

RESUMO

This paper reports a facile, fast, and cost-effective method for the synthesis of three-dimensional (3D) porous AgNPs/Cu composites as SERS substrates for the super-sensitive and quantitative detection of food organic contaminations. Due to the 3D porous hotspot architecture and the strong plasmonic coupling between Ag and Cu, the porous AgNPs/Cu substrate achieves ultrasensitive detection of multiple analytes as low as 10-11 M (crystal violet, CV), 10-9 M (malachite green, MG), 10-11 M (acephate), and 10-9 M (thiram) even with a portable Raman device. Moreover, this 3D solid substrate has good signal uniformity (RSD < 11%) and superior stability (<14% signal loss), allowing for practical SERS detections. Importantly, by simply wiping the real sample surface using the substrate, it successfully detects CV and MG residues on crayfish, and the limit of detection (LOD) of CV and MG is determined to be 1.14 × 10-9 M and 0.94 × 10-7 M, respectively. Further, the substrate can also be applied to detect acephate on eggplant with a LOD of 1.41 × 10-9 M and thiram on an apple surface with a LOD of 1.04 × 10-7 M. Note that all these SERS detections on real samples have a broad dynamic concentration range and a good linear dependence. As a "proof of concept", multi-component detection on a real sample has also been demonstrated. This 3D solid substrate possesses excellent detection sensitivity, diversity, and accuracy, which allows rapid and reliable determination of toxic substances in foods.


Assuntos
Técnicas de Química Analítica/métodos , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Praguicidas/análise , Análise Espectral Raman , Animais , Técnicas de Química Analítica/economia , Cobre/química , Limite de Detecção , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes , Prata/química
14.
Anal Bioanal Chem ; 411(26): 6913-6929, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31418049

RESUMO

A method was developed for the analysis of 22 antiparasitic residues belonging to the benzoylurea, organophosphate, pyrimidinamine, pyrethrin and pyrethroid classes in salmon by liquid chromatography coupled with tandem mass spectrometry. Samples were extracted with acetonitrile-water as the extraction solvent with use of a vibrational shaking apparatus with a ceramic homogenizer. After extraction, the acetonitrile extracts were cleaned up by incubation at low temperature (-20 °C, 1 h) to remove fat, followed by dispersive solid-phase extraction using Z-Sep+ and primary-secondary amine as sorbents. Validation was performed following the 2002/657/EC and SANTE/11813/2017 guidelines. The trueness of the method ranged from 87% to 121% and precision ranged from 4.1% to 23.7%, with the exception of cyphenothrin, dicyclanil and azamethiphos. The method developed is particularly advantageous because the use of a vibrational shaker allows unattended extraction of samples and eliminates a laborious tissue disruption step, which increases sample throughput in the laboratory. The sample preparation and chromatographic separations can be performed in 5 and 4 h, respectively, for 36 samples. Graphical abstract.


Assuntos
Antiparasitários/análise , Praguicidas/análise , Alimentos Marinhos/análise , Animais , Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Drogas/análise , Peixes/metabolismo , Análise de Alimentos/métodos , Limite de Detecção , Resíduos de Praguicidas/análise , Salmão/metabolismo , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
15.
Artigo em Inglês | MEDLINE | ID: mdl-31418625

RESUMO

The article presents the results of a dynamic study (spring, summer, and fall) of the residues of certain xenobiotics such as organochlorine pesticides (OCPs), synthetic surfactants (SSs) in surface water, soil, sludge, snow and phytotoxic activity in Ararat and Lori marzes of Armenia (2016-2017). A comparative analysis of the environmental status showed that all pollutants studied such as γ-hexachlorocyclohexane (γ-HCH), 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (4,4'-DDT), and p-p'-dichlorodiphenyldichloroethylene (4,4'-DDE) were identified in Ararat marz with the average concentrations and detection rates higher than in Lori marz. The prominent contaminant was γ-HCH. The findings indicated the concentrations of OCPs below of regulatory concern. In Ararat marz an increase in the number of sterile pollen grains of certain wild plants was revealed (14.8-26.0%), compared with Lori marz with the levels within the contingent standard of 5-11%. The phytotoxic activity of soil samples from the Ararat marz studied on Avena sativa seedlings was significantly higher in the summer-fall period. These data correlated with monitoring findings showed an increase in the levels of γ-HCH, 4,4'-DDT, SS in the soil and sludge sampled in summer-fall in Ararat marz. This difference in the environmental status can be considered as the result of active agriculture in Ararat marz, whose share of contribution to a relevant branch of the economy of Armenia is two times higher than in Lori marz, 15.4% and 7.9%, respectively. Mentioned rates of agricultural production may be one of the reasons for the environmental deterioration in Ararat marz. The detection of 4,4-DDT, γ-HCH residues testifies the circulation of these formulations in the environment indicating their use in recent past and confirming their persistence. Although since the 70s of the last century the application of OCPs in the Republic of Armenia has been prohibited. The current situation may be explained by low awareness of farmers on different issues related to the safe management of pesticides. To ensure safe working conditions and raise awareness among the farmers we have developed "Recommendations on Safety requirements when working with pesticides" that are approved by the State Service for Food Safety at the Ministry of Agriculture of RA and included in the reference booklets for farmers as guiding information. Our study shows the understanding of associations between the deterioration of the environmental status and share of agriculture contribution to the economy that provides the evidence for future research programs.


Assuntos
Agricultura , Herbicidas/análise , Poluentes do Solo/análise , Solo/química , Xenobióticos/análise , Armênia , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Herbicidas/toxicidade , Humanos , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Estações do Ano , Poluentes do Solo/toxicidade , Testes de Toxicidade , Xenobióticos/toxicidade
16.
Sci Total Environ ; 687: 808-816, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31412484

RESUMO

INTRODUCTION: Vineyard is a crop where a large number of pesticides are applied; exposure to pesticides may occur in farmers and the general population living close to the treated area. This work aimed to investigate hair as a matrix for the assessment of cumulative and aggregate exposure to pesticides in potentially exposed individuals. METHODS: Twenty agricultural workers (AW), 4 agricultural worker relatives (AR), and 5 research staff members (RS) were involved in the study. Hair samples were collected before and after the application season (PRE- and POST-EXP samples) to obtain 18 paired samples. Records with the name and the quantity of applied pesticides were obtained; twenty-seven pesticides were measured in hair by solvent extraction and LC-MS/MS. RESULTS: During the study season, AW applied 14 different pesticides with median amount ranging from 12 to 7200 g. The most popular pesticides were dimethomorph, penconazole, cyazofamid, fenamidone and quinoxyfen, applied from 94 to 69% of AW. In AW, in PRE-EXP samples the majority of used pesticides was detectable (with detection rates from 6 to 88%), with median concentrations of few pg/mg hair; in the POST-EXP samples the frequency of detected values increased (from 25 to 100%), with median concentrations up to two orders of magnitude higher. In AR, most pesticides were quantifiable only in POST-EXP samples and with lower concentration in comparison with AW; in RS, in both PRE- and POST-EXP samples only a few pesticides were quantifiable with very low levels. In AW, a linear correlation (r = 0.682 on log-transformed data, p < 0.01) was found between the total amounts of applied pesticides during the season and their concentration in hair. CONCLUSION: The study shows that the majority of assessed pesticides was incorporated into hair of AW and AR. The increased frequency of detection and level at the end of the season and the correlation between pesticide in hair and the amount of applied pesticides, reinforce the use of hair for quantitative biomonitoring of cumulative exposure to pesticides.


Assuntos
Fazendas , Cabelo/química , Exposição Ocupacional/análise , Praguicidas/análise , Cromatografia Líquida , Monitoramento Ambiental , Fazendeiros , Humanos , Exposição Ocupacional/estatística & dados numéricos , Espectrometria de Massas em Tandem
17.
Ecotoxicol Environ Saf ; 183: 109489, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31394379

RESUMO

Avermectins and moxidectin are antiparasitics widely used as active pharmaceutical ingredients in veterinary medicine, as well as in pesticide formulations for pest control in agriculture. Although the use of these compounds provides benefits to agribusiness, they can impact the environment, since a large part of these substances may reach the soil and water from the excreta of treated animals and following direct applications to crops. The present work had the objective of evaluating the dissipation behaviors of abamectin, doramectin, eprinomectin, ivermectin, and moxidectin in four native Brazilian soils of different textural classes (clay, sandy-clay, sandy, and sandy-clay-loam), following OECD Guideline 307. The studies were conducted in a climate chamber at 22 °C, 71% relative humidity, and protected from light. The dissipation studies were carried out with all drugs together, since no difference was verified when studies were done with each drug separately. The concentrations of the drugs in the soils were determined using an ultra-high performance liquid chromatograph coupled to a fluorescence detector or a tandem mass spectrometer. The dissipation half-life (DT50) values ranged from 9 to 16 days and the calculated GUS index values were in the range from -1.10 to 0.08, indicating low mobility of the drugs in the soils evaluated and low tendency for leaching. In addition, a field study was carried out to evaluate the dissipation of abamectin after application of a foliar pesticide in an orange crop. A DT50 of 9 days was determined, which was similar to that obtained under controlled conditions in the climate chamber (12 days), indicating that biotransformation was the primary process influencing the overall dissipation.


Assuntos
Antiparasitários/química , Ivermectina/análogos & derivados , Macrolídeos/metabolismo , Praguicidas/química , Poluentes do Solo/química , Solo/química , Antiparasitários/análise , Brasil , Monitoramento Ambiental , Meia-Vida , Ivermectina/análise , Ivermectina/química , Ivermectina/metabolismo , Macrolídeos/análise , Macrolídeos/química , Praguicidas/análise , Poluentes do Solo/análise
18.
J Forensic Leg Med ; 67: 28-36, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31398663

RESUMO

The application of forensic entomotoxicology in investigations of death by poisoning has gained popularity as insects serves as an alternative specimen (evidence) when conventional toxicological samples have degraded or are no longer available. Successful detection, identification, and quantification of drugs and toxic substances from insects have been demonstrated through various research experiments. In the present review paper, role of insects as toxicological sample, its collection and preservation, analysis using various instrumental techniques, and trends in the use of analytical techniques have been discussed. Limitations hindering the growth of this field and the way forward for future studies have been highlighted. In addition, the effect of poisons on insects used for postmortem interval estimation has been described.


Assuntos
Entomologia , Comportamento Alimentar , Toxicologia Forense/métodos , Envenenamento/diagnóstico , Mudanças Depois da Morte , Animais , Depressores do Sistema Nervoso Central/análise , Besouros , Dípteros , Etanol/análise , Humanos , Larva , Extração Líquido-Líquido , Praguicidas/análise , Preparações Farmacêuticas/análise , Extração em Fase Sólida , Xenobióticos
19.
J Agric Food Chem ; 67(34): 9658-9666, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31381330

RESUMO

The biomimetic enzyme-linked immunosorbent assay (BELISA) is widely used for detection of small-molecule compounds as a result of low cost and reagent stability of molecularly imprinted polymers (MIPs). However, enzyme labels used in BELISA still suffer some drawbacks, such as high production cost and limited stability. To overcome the drawbacks, a biomimetic nanozyme-linked immunosorbent assay (BNLISA) based on MIPs and nanozyme labels was first proposed. For nanozyme labels, platinum nanoparticles (PtNPs) acted as peroxidase by catalyzing the oxidation of colorless 3,3',5,5'-tetramethylbenzidine (TMB) into an ideal surface-enhanced Raman scattering (SERS) marker. Blue TMB2+ and bovine serum albumin (BSA)-hapten showed superior selectivity when competing with targets for binding sites on MIPs, named the Pt@BSA-hapten probe. The BNLISA method was employed to detect triazophos with a limit of detection of 1 ng mL-1 via colorimetric and SERS methods. Replacing traditional enzymes with nanozymes for combination with MIPs may bring about a new prospect for other compound analyses.


Assuntos
Colorimetria/métodos , Organotiofosfatos/análise , Praguicidas/análise , Análise Espectral Raman/métodos , Triazóis/análise , Benzidinas/química , Materiais Biomiméticos/química , Colorimetria/instrumentação , Frutas/química , Ouro/química , Imunoadsorventes/química , Nanopartículas Metálicas/química , Platina/química , Pyrus/química , Sensibilidade e Especificidade , Análise Espectral Raman/instrumentação , Poluentes Químicos da Água/análise
20.
Arch Environ Contam Toxicol ; 77(3): 432-442, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31270566

RESUMO

A pesticide is a chemical substance used for the disposal of pests, such as insects, weeds, invertebrates, or rodents. Pesticides interfere with the normal metabolism of the target species; however, some of them may inadvertently affect organisms other than those targeted. Increased quantities of pesticides in water disturb various ecological processes and may increase the mortality rate of various native species of flora and fauna. One of the groups of organisms that are at the greatest risk from the adverse effects of pesticides is the bivalves. This study was designed to assess the behavioural reaction of bivalves to widespread pesticides. As a representative example, the Polish native Unio tumidus (Philipsson 1788) was used. The study investigated different groups of toxic pesticides, such as herbicides (lenacil), insecticides (thiacloprid, DDT and dichlorvos), and fungicides (tebuconazole), in concentrations of 10 mg L-1. The results showed various behavioural reactions of bivalves to the pesticides. The most evident were activity time and shell opening rate. Moreover, as a result of DDVP contamination, effects were recorded in terms of shell opening level as well as rapid onset of death. Among the five analysed plant protection products, the most toxic was DDVP. Its presence caused adductor muscle paralysis in all analysed individuals. The least toxic pesticides were DDT and thiacloprid. A strong reaction to lenacil was observed especially in the shell opening rate. Tebuconazole caused significant reductions in activity. Despite the fact that the impact of pesticides on ecosystems is under regular observation, with the use of a wide range of scientific techniques, the use of bivalves was shown to have considerable potential for water quality monitoring.


Assuntos
Praguicidas/toxicidade , Unio/efeitos dos fármacos , Unio/fisiologia , Poluentes Químicos da Água/toxicidade , Exoesqueleto/efeitos dos fármacos , Exoesqueleto/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Ecossistema , Ecotoxicologia/instrumentação , Ecotoxicologia/métodos , Biomarcadores Ambientais , Água Doce/química , Praguicidas/análise , Poluentes Químicos da Água/análise , Qualidade da Água
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