Neurotoxicidad de plaguicidas. Breve actualización / Neurotoxicity of pesticides. Brief update

Introducción: Los plaguicidas son necesarios para en el desarrollo de la sociedad actual, aunque suponen un riesgo para la salud pública, el ecosistema, la salud humana, de las personas expuestas directa e indirectamente a través de la cadena alimentaria y/o el medio ambiente. De hecho, cada vez son más los estudios que muestran una neurotoxicidad derivada de una intoxicación aguda y/o crónica por exposición a plaguicidas.Método: Se realizó una breve revisión bibliográfica sobre la toxicidad de estos productos químicos, en relación al daño que pueden causar en el sistema nervioso. Se examinaron artículos científicos publicados en inglés y español, mediante la búsqueda en las bases de datos como: Scielo, Medline, Springer, Scopus y Science Direct, de artículos que fueron divulgados durante el periodo comprendido entre el año 2017 y 2022, según los criterios establecidos por la declaración PRISMA.Resultados: Los plaguicidas suponen uno de los contaminantes ambientales más utilizados, que pueden generar numerosos beneficios para la agricultura; sin embargo, se relacionan cada vez más, con una neurotoxicidad derivada de una exposición crónica, que cursa con el desarrollo de enfermedades crónicas neurodegenerativas.Conclusiones: Se necesitan más estudios que aborden la neurotoxicidad inducida por exposición a plaguicidas, así como, la necesidad de reforzar todos los sistemas de prevención, control y medidas que garanticen la salud de la población expuesta.(AU)

Introduction: Pesticides are necessary for the development of today's society, although they pose a risk to public health, the ecosystem, human health, people directly and indirectly exposed through the food chain and/or the environment. . In fact, more and more studies show neurotoxicity derived from acute and/or chronic poisoning due to exposure to pesticides.Method: A brief bibliographical review on the toxicity of these chemical products was carried out, in relation to the damage they can cause in the nervous system. Scientific articles published in English and Spanish were examined, by searching databases such as: Scielo, Medline, Springer, Scopus and Science Direct, of articles that were disclosed during the period between 2017 and 2022, according to the criteria established by the PRISMA statement.Results: Pesticides are one of the most widely used environmental contaminants, which can generate numerous benefits for agriculture; however, they are increasingly related to neurotoxicity derived from chronic exposure, which occurs with the development of chronic neurodegenerative diseases.Conclusions: More studies are needed to address neurotoxicity induced by exposure to pesticides, as well as the need to strengthen all systems of prevention, control, and measures that guarantee the health of the exposed population.(AU)

Abnormalities in flatfishes of the south-west Atlantic Ocean.

Five adult paralichthyid specimens with various kinds of abnormalities are reported from the south-west Atlantic Ocean. These abnormal flatfish specimens represent the first records of wholly ambicoloured Paralichthys orbignyanus specimens having a deep notch between the eye and dorsal fin and a partially albinistic specimen having skeletal deformities and only the second record of an almost totally ambicoloured specimen. We also report the first observation of reversal in Paralichthys patagonicus and an almost totally ambicoloured, reversed Xystreurys rasile.

Reliable methods for determination of triazine herbicides and their degradation products in seawater and marine sediments using liquid chromatography-tandem mass spectrometry.

Triazines and their degradation products are transported to the aquatic environment, and once there, the probability to reach the marine environment is very high. In this paper, solid phase extraction (SPE) and extraction by matrix solid phase dispersion (MSPD) to analyse nine triazines (ametryn, atrazine, cyanazine, prometryn, propazine, simazine, simetryn, terbuthylazine and terbutryn) and eight degradation products (desethylatrazine, desethyldesisopropylatrazine, desethyl-2-hydroxyatrazine, desethylterbuthylazine, desisopropylatrazine, desisopropyl-2-hydroxyatrazine, 2-hydroxyatrazine and 2-hidroxyterbuthylazine) in seawater and marine sediments samples were used. The analysis was carried out using liquid chromatography with tandem mass spectrometry (LC-ESI-MS/MS). The methods were optimized and validated to achieve a selective and sensitive determination of the analytes from different sample, regardless of its complexity. Under the optimum conditions, the proposed methods provided adequate limits of quantification (0.05-0.45 µg L-1 and 0.23-4.26 µg kg-1 in seawater and marine sediments, respectively). Intra- and inter-day relative standard deviation were below 1.41% for all compounds. Recoveries were evaluated, and acceptable values that ranged from 87.5-99.4 and 60.9-99.7% for the seawater and sediment samples, respectively, were obtained. The proposed methods were applied to the analysis of the target compounds in seawater samples and marine sediments from a coastal area of Galicia (NW of Spain).

On-line solid-phase extraction method for determination of triazine herbicides and degradation products in seawater by ultra-pressure liquid chromatography-tandem mass spectrometry.

A fast, simple, selective and sensitive method has been developed for the determination of nine triazine herbicides (ametryn, atrazine, cyanazine, prometryn, propazine, simazine, simetryn, terbuthylazine and terbutryn) and eight degradation products (desethyl atrazine, desethyl-desisopropyl atrazine, desethyl 2-hydroxyatrazine, desethyl terbuthylazine, desisopropyl atrazine, desisopropyl 2-hydroxyatrazine, 2-hydroxyatrazine and 2-hidroxyterbuthylazine) in seawater samples. On-line solid-phase extraction coupled with ultra-pressure liquid chromatography-tandem mass spectrometry was employed for simultaneous analysis of all compounds in 11min. Validation parameters were studied through the estimation of the limits of detection and quantification, calibration curves and precision. Limits of quantification ranged from 0.023 to 0.657µgL-1. Good linearity was obtained for all compounds with R2>0.99 in all cases. Furthermore, inter-day precision (0-2.1%) and intra-day precision (0-3.9%) were shown to be satisfactory. On-line solid-phase extraction recoveries in spiked unpolluted seawater sample were evaluated and acceptable values (80.3-99.8%) with adequate RSD (0.1-3.1%) were found. Finally, the proposed method was applied to the analysis of the target compounds in seawater samples collected from seawater nearby a zone of intensive horticulture of Matosinhos (Portugal). The concentrations of the herbicides were below the limit of detection in all cases.

New tools (DNA barcoding), old hypothesis: the case of the taxonomic identity of the Argentine hakes (Actinopterygii: Merluccius).

The present study evaluated the possible occurrence of cryptic species among Merluccidae from Argentina by examining sequences of cytochrome c oxidase subunit I (coI) mtDNA. This approach can discriminate Merluccius hubbsi and Merluccius australis; specimens with morphological diagnostic characters of Merluccius patagonicus formed a cohesive cluster with M. hubbsi specimens. BIN analysis confirmed the effectiveness of barcoding within a global context.

Development of a Matrix Solid Phase Dispersion methodology for the determination of triazine herbicides in mussels.

A method based on Matrix Solid Phase Dispersion (MSPD) for determination of nine triazines in mussels has been optimised in terms of the sorbents used for extracting and cleaning-up. Two dispersing agents: C18 and florisil, and eight cleanup co-sorbents: florisil, silica, silica/alumina, Envi™ Carb, Envi-Carb-II/PSA, SAX/PSA, Envi-Carb-II /SAX/PSA and C18 were assayed. Analytes were eluted using 20 mL of ethyl acetate and 5 mL of acetonitrile and finally the extract was concentrated to dryness, re-constituted with 1 mL methanol and determined by HPLC-DAD. The best results were obtained with C18 as dispersing agent and Envi-Carb-II/SAX/PSA as clean-up co-column. Recoveries ranged between 79% and 99% and repeatability and reproducibility were below than 16% for all compounds. The linearity of the calibration curves yielded the R(2)⩾0.9993. The LOQ values ranged from 0.10 to 0.18 mg kg(-1) dried sample. Finally the method was applied to the analysis of mussel samples from Galicia (NW Spain).

An environmentally friendly method for the determination of triazine herbicides in estuarine seawater samples by dispersive liquid-liquid microextraction.

A fast, simple, sensitive and green chemistry method using dispersive liquid-liquid microextraction (DLLME) for the simultaneous determination of seven triazine herbicides (ametryn, atrazine, cyanazine, propazine, simazine, simetryn and terbuthylazine) in estuarine seawater samples has been developed. DLLME was carried out using a small volume of seawater (25 mL) and 300 µL of 1-octanol. Herbicide concentrations were determined by liquid chromatography-diode array detection, and results were confirmed by liquid chromatography-electrospray ionisation tandem spectrometry analysis. The analytical features of the proposed method were satisfactory with repeatability < ±5% and intermediate precision < ±10%, and recoveries ranged from 81-102% for all compounds. All the triazines exhibited linear matrix calibration curves with coefficients of determination >0.999 for all the analytes except for simazine (0.9975). Limits of quantification ranged between 0.19 and 1.12 µg L(-1). The method was applied to the analysis of seawater samples from ten points susceptible to contamination by triazines from estuary of A Coruña (Galicia, NW of Spain). The levels of the seven triazines were below the LODs in the analysed samples. Use of proposed method will allow for monitoring of triazines at levels below the regulatory limits set by the European Directive 2008/105/EC of 2 and 4 µg L(-1) for atrazine and simazine, respectively.

Determination of triazine herbicides in seaweeds: development of a sample preparation method based on Matrix Solid Phase Dispersion and Solid Phase Extraction Clean-up.

A method using dual process columns of Matrix Solid Phase Dispersion (MSPD) and Solid Phase Extraction (SPE) has been developed for extracting and cleaning-up of nine triazine herbicides (ametryn, atrazine, cyanazine, prometryn, propazine, simazine, simetryn, terbuthylazine and terbutryn) in seaweed samples. Under optimized conditions, samples were blended with 2g of octasilyl-derivatized silica (C8) and transferred into an SPE cartridge containing ENVI-Carb II/PSA (0.5/0.5 g) as a clean up co-sorbent. Then the dispersed sample was washed with 10 mL of n-hexane and triazines were eluted with 20 mL ethyl acetate and 5 mL acetonitrile. Finally the extract was concentrated to dryness, re-constituted with 1 mL methanol:water (1:1) and injected into the HPLC-DAD system. The linearity of the calibration curves was excellent in matrix matched standards, and yielded the coefficients of determination>0.995 for all the target analytes. The recoveries ranged from 75% to 100% with relative standard deviations lower than 7%. The achieved LOQs (<10 µg kg(-1)) for all triazines under study permits to ensure proper determination at the maximum allowed residue levels set in the European Union Legislation. Samples of three seaweeds were subjected to the procedure proving the suitability of MSPD method for the analysis of triazines in different seaweeds samples.

Morphological, morphometric, meristic and osteological evidence for two species of hake (Actinopterygii: Gadiformes: Merluccius) in Argentinean waters.

Morphologically, both classic and landmark-based morphometry and meristic analyses of 241 specimens of Merluccius, along with the re-examination of six paratype specimens of Merluccius hubbsi, the holotype and three paratypes of Merluccius patagonicus and the syntype of Merluccius australis revealed the presence of only two species of Merluccius in Argentinean waters. Internal structures (hyomandibula, urohyal and sagitta otolith) of M. hubbsi were compared to those reported for M. patagonicus and were shown to have identical morphology. Type specimens of M. patagonicus showed a complete overlap in morphometric and meristic characters with M. hubbsi, whereas M. australis had a greater number of second dorsal and anal-fin rays, and more lateral-line scales. In addition, M. australis had a smaller eye and longer snout than M. hubbsi and M. patagonicus. The results indicate that there is no evidence for a third hake species in Argentinean waters. Merluccius patagonicus is a synonym of M. hubbsi.

Phthalates and bisphenols migration in Mexican food cans and plastic food containers.

The presence of endocrine disruptors bisphenol-A, bisphenol-A-dimethacrylate, bisphenol-A-diglycidyl-ether, phthalic-acid, dibutyl-phthalate, diethyl-phthalate and dioctyl-phthalate was determined in vegetable cans, baby bottles and microwaveable containers from the Mexican market. Gas-Chromatography-Mass-Spectrometry was used for the identification and High-Performance-Liquid-Chromatography with UV/Visible light and fluorescence detectors was used for the quantification. Endocrine disruptors were found in all samples. PA and DOP were the substances most commonly found, and maximum concentrations were 9.549 and 0.664 µg/kg, respectively from a jalapeno peppers can. Bisphenol A, phthalic-acid, bisphenol-A-dimethacrylate, bisphenol-A-diglycidyl-ether, dioctyl-phtalate and dibutyl-phthalate were found in baby bottles and microwaveable containers.

First record of Mugil hospes in the Gulf of Mexico and its identification from Mugil curema using ctenii.

This study gives the first record of Mugil hospes distributed in the Gulf of Mexico. This species previously has been confused with its congener Mugil curema and can be easily differentiated by the shape of the ctenii on their scales.

Determination of organochlorine pesticides in vegetable matrices by stir bar sorptive extraction with liquid desorption and large volume injection-gas chromatography-mass spectrometry towards compliance with European Union directives.

A novel analytical approach to determine trace levels of 20 organochlorine pesticides (OCPs) in nine vegetable matrices (lettuce, spinach, green bean, green pepper, tomato, broccoli, potato, carrot and onion) is proposed, based on stir bar sorptive extraction followed by liquid desorption and large volume injection-gas chromatography coupled to mass spectrometry using the selected-ion monitoring mode acquisition (SBSE-LD/LVI-GC-MS(SIM)). The experimental procedure consists of a previous ultrasonic extraction of the freeze-dried vegetable samples (100.0mg) with methanol (2mL) followed by centrifugation and dissolution in aqueous media prior to SBSE-LD/LVI-GC-MS(SIM) under optimised conditions. Assays were performed on 30mL aqueous samples using stir bars coated with 47microL of polydimethylsiloxane, an equilibrium time of 180min (1000rpm; 20 degrees C) and acetonitrile as back-extraction solvent, providing convenient analytical performance to monitor OCPs in vegetable matrices at the trace level. Besides the selectivity reached, the data obtained clearly demonstrate that the matrices involved have a strong effect on the recovery yields (10-110%) of the OCPs under study, in particular the green vegetables especially the leafy ones. By using the standard addition methodology, good linearity (r(2)>0.99) and convenient precisions (RSD<20%) were found for almost all cases, depending on the particular OCP and vegetable matrix involved. Furthermore enough sensitivity was also achieved (limit of detection <10microgkg(-1)) for all OCPs under study towards compliance with the European Union regulations for the maximum residue limits of pesticides in agricultural vegetables. The methodology showed to be easy of work-up, fast, almost solventless with low sample amount requirement, when compared with conventional methods of sample preparation to screen pesticides in vegetable matrices.

Development of an analytical method based on microwave-assisted extraction and solid phase extraction cleanup for the determination of organochlorine pesticides in animal feed.

A method to determine 21 organochlorine pesticides in animal feed samples using microwave assisted extraction and solid phase extraction cleanup was optimised regarding its main parameters. After extraction with hexane-acetone (50:50), three different sorbents (alumina/ENVI-Florisil, ENVI-Carb and ENVI-Carb II/PSA) were assayed for the cleanup step. Analytes were eluted with hexane-ethyl acetate (80:20) and determined by gas chromatography and electron capture detection followed by gas chromatography-mass spectrometry. ENVI-Carb and ENVI-Carb II/PSA provided colourless eluates but fewer interferent compounds were found in ENVI-Carb II/PSA chromatograms, so this system was selected to carry out the purification of the extracts. The analytical recoveries obtained with this method were close to 100% in most cases with relative standard deviations lower than 10%. These percentages were similar to those obtained with the Soxhlet extraction procedure, which shows the method suitable for the determination of organochlorine pesticides in animal feed material. The method was also validated with the analysis of a certified reference material (CRM-115 BCR), and the results obtained were in good accordance with the certified values.

Comparison of pressurized liquid extraction and microwave assisted extraction for the determination of organochlorine pesticides in vegetables.

A method to determine organochlorine pesticides in horticultural samples (lettuce, tomato, spinach, potato, turnip leaf and green bean) using pressurized liquid extraction (PLE) is described and compared with microwave assisted extraction (MAE). Significant parameters affecting PLE procedure such as temperature, static extraction time and extraction solvent were optimised and discussed. Clean-up of extracts was performed by solid phase extraction (SPE) using a carbon cartridge as adsorbent. Pesticides were determined by gas chromatography and electron capture detection (GC-ECD). Analytical recoveries obtained were ca. 100% and the relative standard deviations were lower than 15% for most of the studied pesticides with the proposed methods in each analysed matrix.

Determination of 21 organochlorine pesticides in tree leaves using solid-phase extraction clean-up cartridges.

A method to determine 21 organochlorine pesticides (OCPs) in tree leaves [chestnut (Castanea sativa), hazel (Corylus avellana), oak (Quercus robur) and walnut tree (Juglans regia)] based on microwave-assisted extraction (MAE) followed by solid-phase extraction (SPE) clean-up is described. After extraction with hexane:acetone (50:50), four different sorbents (Florisil, tandem Florisil + alumina, silica and ENVI-Carb) were assayed for the clean-up step. Pesticides were eluted with 5 mL of hexane:ethyl acetate (80:20) and determined by gas chromatography and electron capture detection (GC-ECD). Carbon was the sorbent, which provided colourless eluates and chromatograms with less interferent compounds. Analytical recoveries obtained were ca. 100% for all the studied pesticides with this sorbent.

Microwave-assisted extraction versus Soxhlet extraction in the analysis of 21 organochlorine pesticides in plants.

A method to determine 21 organochlorine pesticides in vegetation samples using microwave-assisted extraction (MAE) is described and compared with Soxhlet extraction. Samples were extracted with hexane-acetone (1:1, v/v) and the extracts were cleaned using solid-phase extraction with Florisil and alumine as adsorbents. Pesticides were eluted with hexane-ethyl acetate (80:20, v/v) and determined by gas chromatography and electron-capture detection. Recoveries obtained (75.5-132.7% for Soxhlet extraction and 81.5-108.4% for MAE) show that both methods are suitable for the determination of chlorinated pesticides in vegetation samples. The method using microwave energy was applied to grass samples from parks of A Coruña (N.W. Spain) and to vegetation from the contaminated industrial area of Torneiros (Pontevedra, N.W. Spain).

High-performance liquid chromatographic determination of glycogen in sea urchin gonads with refractive index detection.

A high-performance liquid chromatographic method using refractive index detection for the determination of glycogen in sea urchin (Paracentrotus lividus) gonads is developed. After alkaline digestion with sodium carbonate, samples are adjusted to pH 4.6 with citric acid and incubated with amyloglucosidase to hydrolyze the glycogen. The resulting glucose is determined using a Spherisorb NH2 column as the stationary phase and an acetonitrile-water mixture (80:20, v/v) as the mobile phase. The relative standard deviation (%) was 3.57, the limit of detection was 40.1 microg/mL, and the recovery percentage was 97.2%.

[The stability of the microalbuminuria numbers in relation to their reading time and mode of preservation]. / Estabilidad de las cifras de microalbuminuria en relación con el tiempo de lectura y el modo de conservación.

OBJECTIVE: To evaluate the stability of microalbuminuria figures in urine samples of diabetic patients, in terms of how the samples are kept, and the time between taking and reading. DESIGN: Descriptive, prospective and observational study. SETTING: Primary care. Teaching health centre, Burgos. PATIENTS: 40 type-2 diabetics had their urinary excretion of albumin measured in 91 first-in-the-morning urine samples with Micral Test II reactive strips. INTERVENTIONS: Samples were analysed the day of their collection, then protected from light and kept at +4 degrees C, with further readings at 24, 48 and 72 hours and at 7, 14, 21 and 28 days after collection. MEASUREMENTS AND MAIN RESULTS: 49 (53.84%) of the 91 samples taken did not vary over the 28 days of the study. In the first three days, there were 64 with unvaried measurements (70.2%). Friedman's test showed p = 0.905. > 93% of samples positive at the beginning remained positive all the time; > 83% of samples negative at the beginning remained negative. Concordance observed was > 90%; kappa index > 80%. CONCLUSIONS: Collection of first urine samples in the morning, stored at +4 degrees C in a fridge and protected from light, did not significantly alter the result of the reading for 4 weeks. Such samples are useful in order to aid study of the albumin excretion rate using Micral Test II reactive strips.

Determination of volatile components in fresh, frozen, and freeze-dried Padrón-type peppers by gas chromatography-mass spectrometry using dynamic headspace sampling and microwave desorption.

"Padrón-type" peppers are a small variety of Capsicum annuum cultivated mainly in Galicia, Spain. To compare the effects of freezing and freeze-drying on the volatile components of Padrón-type peppers, preserved samples are analyzed by means of dynamic headspace sampling on an adsorbent followed by microwave desorption into a gas chromatograph equipped with a mass spectrometric detector. Sixty-five compounds are identified, including hydrocarbons, terpenes, alcohols, phenols, ethers, aldehydes, ketones, esters, pyrroles, pyrazines, and sulfurous compounds. Fresh whole, homogenized, and freeze-dried peppers have characteristic volatile-component profiles, whereas frozen peppers have a highly variable volatile-component profile.

[The effects of long-term captopril treatment on the evolution of urinary albumin excretion in patients with non-insulin-dependent diabetes mellitus]. / Efectos del tratamiento a largo plazo con captopril sobre la evolución de la excreción urinaria de albúmina en pacientes con diabetes mellitus no insulinodependiente.

OBJECTIVES: To identify diabetics not dependent on insulin (DNDI) who are carriers of clinical proteinuria and microalbuminuria susceptible to captopril treatment and to evaluate the evolution of the urinary excretion of albumin (UEA) rate after three years of follow-up. DESIGN: A prevalence study followed by an intervention and follow-up over 3 years. SETTING: The urban Health Centre "San Agustín" in Burgos. PATIENTS: 107 DNDI included in the "Diabetes programme". INTERVENTIONS: Patients with increased UEA were treated with 25 mg of captopril (Capoten) every 12 hours for 3 years. MEASUREMENTS AND RESULTS: A steady drop in the UEA of patients with microalbuminuria was observed in their third year of treatment (p = 0.01). 5 patients (41.6%) became negative (p = 0.01). CONCLUSIONS: Captopril treatment reduced levels of UEA in DNDI who had high UEA. Significantly, evolution to clinical proteinuria of patients with persistent microalbuminuria was avoided.