Selenium intake from tuna in Galicia (Spain): Health risk assessment and protective role against exposure to mercury and inorganic arsenic.

This study aims to quantify the selenium contribution from tuna to the Spanish diet and evidence the Se protective role against mercury and inorganic arsenic toxicity. Selenium concentrations in tuna were determined by ICP-MS spectrometry (expressed as mg kg-1), and the risk assessment was evaluated joined to Hg and iAs contrasting criteria of regulatory agencies with those that consider the Se protective role. Differences between Se average concentrations in fresh (1.24) and preserved (1.17) tuna were not statistically significant. In canned tuna species, Se presented higher mean levels in Thunnus albacares (1.28) than Thunnus alalunga (1.01) with statistically significant differences (p = 0.002), and among canned preparations a decreasing sequence was observed in different preparation-packaging media: oil (1.42) > natural (1.01) > pickled (0.92). Statistical study showed Hg-iAs as the only pair significantly correlated in all samples. The HI (sum of individual target hazard quotients -THQs-) on the consumption of tuna in Spain, due to exposure to Se, Hg and iAs, revealed the possibility of risk of adverse chronic effects in the six-year-old children group (1.09). According to the maximum allowable tuna consumption rate in meals/week (CRmw) and the THQs obtained, tuna intake, especially in children, should be moderated. The health benefit values (HBVSe) were positive in all samples, 14.53 and 15.65 in fresh and preserved tuna, respectively, which allows tuna to be considered safe. The benefit-risk value (BRV) evidenced the Se molar excess with respect to Hg that reached a surplus of 14.32% on Se AI in adults. Since iAs reduces the Se bioavailability, applying a new BRV criterion, the aforementioned percentage decreased to 13.49% of Se AI. In conclusion, tuna offers high levels of selenium to counteract adverse effects by the presence of Hg and iAs, and to provide consumers an important source of this essential element safely.

Arsenic, cadmium and lead in fresh and processed tuna marketed in Galicia (NW Spain): Risk assessment of dietary exposure.

Currently, metal bioaccumulation in fish is increasing and is a cause of concern due to toxicity. Total arsenic, cadmium and lead concentrations in fresh and processed tuna (110 samples) marketed in Galicia (NW Spain) were determined by ICP-MS spectrometry. The average concentrations of As and Cd, 3.78 and 0.024 mg kg-1 w.w., respectively, in fresh tuna were statistically significantly higher than those in processed tuna (p < 0.001). The contents in processed tuna were 0.295-7.85 mg kg-1 for As and ND-0.045 mg kg-1 for Cd. The Pb content was negligible in both types of tuna. In canned tuna, decreasing As and Cd concentrations were observed in different preparation-packaging media: olive oil > natural > pickled sauce. Of the two species studied in canned tuna, Thunnus alalunga showed statistically significant higher levels both for As 1.28 mg kg-1 (p < 0.001) and Pb 0.013 mg kg-1 (p = 0.0496) than Thunnus albacares. No samples surpassed the limits set by the EU for Cd and Pb. The limit for As in fish has not been established, but the arsenic contents in fresh tuna reported here are important, as they are among the highest reported in the literature. Considering public health in children and adults with respect to the investigated metals, the estimated daily intakes (EDIs) did not exceed the tolerable intakes. No chronic systemic risk was found since all the target hazard quotients (THQs-TTHQs) were far below 1 (critical value), and the carcinogenic risk (CR) for As did not exceed the acceptable value of 10-5. Thus, tuna consumption in the Galician diet does not pose a risk for different population groups in terms of these studied metals/metalloids.

Total mercury in fresh and processed tuna marketed in Galicia (NW Spain) in relation to dietary exposure.

Mercury is a toxic trace metal, which can accumulate to levels threatening human and environmental health. In this study, contents of total mercury have been determined by ICP-MS spectrometry in fresh and processed tuna (110 samples) purchased from supermarkets in NW Spain. Mercury was present in all samples analyzed; however, only one sample of fresh tuna (1.070 mg kg-1 wet weight (w.w.)) slightly exceeded the limit of the EU (1.0 mg kg-1 w.w.). The average mercury concentration in processed tuna was lower than fresh, 0.306 mg kg-1 w.w., and ranged from 0.080 to 0.715 mg kg-1 w.w. Results were compared with literature data. In regard to the three types of preparation-packaging media for canned tuna, total Hg content was found in the following order: olive oil > natural > pickled sauce; the last showed significant statistical differences (p < 0.01) with the other two preparations. Between the two evaluated canned tuna species, significant statistical differences (p = 0.008) were observed and Thunnus alalunga presented a greater mean content (0.332 ± 0.114 mg kg-1 w.w.) compared to Thunnus albacares (0.266 ± 0.171 mg kg-1 w.w.).Taking into account the AESAN recommendation for adults and children, as well as the EU regulations and the tuna consumption by the Spanish population, the Hg levels obtained in this study pose no risk to consumer health. However, additional studies, a monitoring process, and efforts to reduce Hg concentration in tuna would be necessary, as well as considering other sources of exposure to Hg.

Cadmium in edible mushrooms from NW Spain: Bioconcentration factors and consumer health implications.

Mushrooms do not constitute a significant portion of the human diet, but the consumption of wild and cultivated mushrooms has become increasingly in recent years. Some species accumulate high levels of toxic metals, both in unpolluted and polluted areas. In this study, we examined the accumulation capacity of cadmium in edible mushrooms in relation to certain factors and their possible toxicological implications. Cadmium concentrations were determined by an ICP-MS spectrometer in 238 samples of the fruiting bodies of 28 wild and cultivated growing edible mushrooms species and the underlying soil. The hymenophore (H) and the rest of the fruiting body (RFB) were analysed separately. The highest mean cadmium concentration (mg/kg dry weight) was found in Agaricus macrosporus (52.9 in H and 28.3 in RFB). All mushroom species accumulated cadmium in relation to the underlying soils. There were statistically significant differences between the hymenophore and the rest of the fruiting body (p < 0.001). Cadmium concentrations were compared to data in the literature and to levels set by legislation. It was concluded that consumption of our studied mushrooms is not a toxicological risk as far as cadmium content is concerned, although the species A. macrosporus should not be consumed.

Radiocaesium activity concentrations in macrofungi from Galicia (NW Spain): Influence of environmental and genetic factors.

Radiocaesium ((137)Cs) is an artificial radionuclide that can be captured from the soil through the mycelium of fungi. However, in Spain there are few data on its presence in edible mushrooms. (137)Cs activity concentrations were determined using 54 samples of wild and cultivated mushrooms and 18 samples of soil, all of them collected in Galicia (NW Spain) during 2010. Samples were analyzed by gamma spectroscopy with a High-Purity Germanium (HPGe) detector. The average activity concentration of (137)Cs in wild mushrooms was 249.2Bqkg(-1) dry weight (dw) and about 24.9Bqkg(-1) fresh weight (fw). Genetic factors (species) influenced the uptake of (137)Cs, highlighting Hydnum repandum as the greatest accumulator of all wild species (1016.4Bqkg(-1) dw), while cultivated species showed much lower levels (1.6Bqkg(-1) fw). Accumulation was also favored by fungal mycorrhizal ecology, whose mycelium was distributed in contaminated soil horizons. The mean levels detected in soils were 14Bqkg(-1) fw. Although some species behaved as bioexclusors of radiocaesium, the transfer factors (TF) suggest that mushrooms preferentially bioaccumulate (137)Cs. No sample reached the limit of 600Bqkg(-1) fw (about 6000Bqkg(-1) dw) indicated in the European legislation. In conclusion, the consumption of mushrooms harvested from the investigated areas poses no toxicological risk to human health due to radiocaesium.

Total contents of arsenic and associated health risks in edible mushrooms, mushroom supplements and growth substrates from Galicia (NW Spain).

The levels of arsenic (As) in the main commercial species of mushrooms present in Galicia, in their growth substrates, and mushroom supplements have been analysed by ICP-MS, with the intention of assessing potential health risks involved with their consumption. The mean concentrations of As in wild and cultivated mushrooms was 0.27mg/kg dw, in mushroom supplements 0.40mg/kg dw, in soils 5.10mg/kg dw, and in growth substrate 0.51mg/kg dw. No significant differences were observed between species, although the species Lactarius deliciosus possessed a slightly more elevated mean concentration (at 0.49mg/kg dw) than the other species investigated. In soils, statistically significant differences (p<0.05) were observed according to geographic origin. Levels in mushroom supplements, although low, were higher than in wild or cultivated mushrooms. Measured arsenic levels were within the normal range in samples analysed in unpolluted areas. Because of the low As concentrations found in fungi and mushroom supplements from Galicia, and considering the relatively small inclusion of these foods in people's diet, it can be concluded that there is no toxicological risk of arsenic associated with the consumption of the species of mushrooms analysed or at the dosages indicated for mushroom supplements.

Seguridad alimentaria por la presencia de 137Cs en hongos comestibles comerciales recogidos en Galicia / Food safety for the presence of 137Cs in commercial edible mushrooms collected in Galicia

Las setas son captadoras de 137Cesio, radionucleido artificial de origen antropogénico, y en España apenas hay datos sobre la presencia de 137Cs en hongos silvestres comestibles. El objeto de este trabajo fue determinar los niveles de 137Cs en las principales especies de hongos silvestres comerciales de Galicia y valorar la influencia de diversos factores en su captación y sus repercusiones alimentarias. Se recogieron 54 muestras de hongos (9 especies silvestres y 5 cultivadas), siendo procesadas y analizadas mediante espectrometría gamma de germanio hiperpuro (HPGe). Como resultados, la concentración media de 137Cs en los hongos silvestres fue 249,2 Bq/kg peso seco (p.s.), equivalente a 24,9 Bq/kg peso fresco (p.f.). La especie más acumuladora fue Hydnum repandum (1016,4 Bq/kg p.s.) y las especies cultivadas mostraron niveles muy inferiores (1,6 Bq/kg p.s.). La contaminación por 137Cs probablemente tenga su origen en el accidente de Chernóbil, aunque con niveles mucho más bajos a los de países próximos al lugar del desastre. La acumulación por hongos estuvo favorecida por su ecología micorrízica, cuyo micelio se distribuye en horizontes del suelo contaminado; asimismo, factores genéticos (especie) influyeron en la captación. En este estudio, ninguna muestra alcanzó el límite de 600 Bq/kg p.f. indicado en la legislación europea vigente (aproximadamente 6000 Bq/kg p.s. referido a hongos si tenemos en cuenta el nivel medio habitual de peso seco del 10%), concluyendo que no existe riesgo alimentario asociado al consumo habitual de las especies de hongos comerciales recogidos en Galicia (AU)

Mushrooms can capture the artificial radionuclide 137Cesium and in Spain there are no data on the presence of 137Cs in wild edible mushrooms. The purpose of this study was to determine the levels of 137Cs in the main commercial wild mushroom species in Galicia and assess the influence of various factors on its uptake and its implications in food safety. 54 samples of fungi (9 wild and five cultivated) were collected, being processed and analyzed by gamma spectrometry hyperpure germanium (HPGe). As results, the average concentration of 137Cs in wild mushrooms was 249.2 Bq/kg dry weight (dw), about 24.9 Bq/kg fresh weight (fw). Hydnum repandum was the most accumulator species (1016.4 Bq/kg dw), and the cultivated species showed much lower levels (1.6 Bq/kg dw). 137Cs contamination, probably, has its origin in the Chernobyl accident, although with far lower levels than those of countries close to the disaster site. The accumulation was favored by fungal mycorrhizal ecology, whose mycelium is distributed in contaminated soil horizons; also, genetic factors (species) influenced the uptake. In this study, no sample reached the limit of 600 Bq/kg fw, indicated in the European legislation (about 6000 Bq/kg dw based on fungi, if we consider the usual average of 10% dry weight in these matrices), concluding that there is no health risk associated with the regular consumption of fungal species collected commercial in Galicia (AU)

Bioconcentration of chromium in edible mushrooms: influence of environmental and genetic factors.

Chromium concentrations were determined in 167 samples of wild edible mushrooms, collected from three different sites (urban, traffic and pastureland areas) in Lugo (NW Spain). The hymenophore (H) and the rest of the fruiting body (RFB) were analysed separately. The analyses were performed using inductively coupled plasma optical emission spectrometry (ICP-OES). The highest mean chromium levels (mg/kg dry weight) of 3.5 and 8.0, 4.5 and 6.2, and 6.2 and 4.3 were found in Lycoperdon utriforme, Coprinus comatus and Agaricus campestris in H and RFB, respectively. The highest concentrations of chromium were observed in terrestrial saprophytic species in relation to mycorrhizal species. With respect to the underlying substrates, chromium concentration was lowest in the pastureland area (24.6 mg/kg dw). All mushroom species were bioexclusors of chromium (BCF<1) with statistically significant differences (p<0.001). The consumption of mushrooms harvested from the areas investigated poses no toxicological risk to human health due to chromium.

Triazine residues in raw milk and infant formulas from Spanish northwest, by a diphasic dialysis extraction.

Residue levels of herbicides (triazines) were determined in milk by a new and sensitive analytical method. A total of 312 samples were collected (70 infant formulas and 242 raw milk) biweekly during a 24-month period. A method is reported for the analysis of triazine with extraction by diphasic dialysis and determination by gas chromatography with nitrogen-phosphorus detection (CG/NPD) and by liquid chromatography/mass spectrometry (LC/MS) to confirm positive results. Detection limits (LODs) were 0.01 mg/l for terbuthylazine, 0.07 mg/l for simazine and 0.04 mg/l for atrazine by CG/NPD. Optimal extraction was obtained with dichloromethane at 34 °C, and stirring at 200 rpm for 4 h. This extraction method improves recovery by up to 89% for terbuthylazine, 75% for simazine and 116% for atrazine. The frequency of total samples containing triazine residues was 12.50%; considering, separately, raw milk and infant formulas, this percentage was 16.11% and 5.71%, respectively. Finally, because one sample contained triazine levels slightly higher than established MRLs and owing to the known effects of these contaminants on infants health and development, urgent actions are needed for monitoring and controlling of the level of contamination in infant formula which not exceeds tolerable limit recommended by European and Spanish legislation.

Organophosphorus pesticide residues in raw milk and infant formulas from Spanish northwest.

Residue levels of seven organophosphorus pesticides (OPPs), widely used as dairy cattle ectoparasiticides or in crops used for animal feed, were determined in raw milk and infant formulas. A total of 312 samples were collected (70 from infant formulas and 242 from raw milk) biweekly during a 24-month period. Pesticides were extracted by means of a solid phase system into acetone. An extract aliquot of acetone was injected into a gas chromatograph (GC) with a nitrogen-phosphorus detector. Recoveries of pesticides spiked in milk samples were 62.2 - 97.2 %. The frequency of total samples containing detectable levels of OPP residues was 6.73 % in total milk and 8.67 % in raw milk. The highest percentage incidence measured was for dichlorvos (5.78 %), followed by coumaphos (2.06 %), and parathion methyl (0.83 %). The range of positive results was calculated to be between 0.005 and 0.220 mg kg(- 1). No residue was detected in the final product (infant formulas), so any risk to consumer health, especially to children's health, would be limited.

Mercury in edible mushrooms and underlying soil: bioconcentration factors and toxicological risk.

Wild growing mushrooms are a popular delicacy in many countries, but some species accumulate high levels of toxic heavy metals, e.g., mercury, both in unpolluted and mildly polluted areas. In this study, we examined the accumulation capacity of mercury in edible mushrooms in relation to certain factors and their possible toxicological implications. Total concentrations of mercury were determined by an anodic stripping voltammetric technique using a gold disc as the working electrode in 238 samples of the fruiting bodies of 28 wild growing edible mushrooms species and the underlying soil. The mushrooms were collected from different sites in the province of Lugo (NW Spain). The hymenophore (H) and the rest of the fruiting body (RFB) were analysed separately. The highest mean mercury concentrations (mg/kg dry weight) were found in Boletus pinophilus (6.9 in H and 4.5 in RFB), Agaricus macrosporus (5.1 in H and 3.7 in RFB), Lepista nuda (5.1 in H and 3.1 in RFB) and Boletus aereus (4.6 in H and 3.3 in RFB), while the lowest was found in Agrocybe cylindrica (0.34 in H and 0.26 in RFB) and Fistulina hepatica (0.30 in H and 0.22 in RFB). All mushroom species accumulated mercury (BCF>1) in relation to the underlying soils. There were no statistically significant differences between the mercury levels in the hymenophore and in the rest of the fruiting body. The total mercury concentrations were compared to data in the literature and to levels set by legislation. It was concluded that consumption of the majority of the studied mushrooms is not a toxicological risk as far as mercury content is concerned, although the species B.pinophilus, A.macrosporus, L.nuda and B.aereus should be consumed in low amounts.

Lead in edible mushrooms: levels and bioaccumulation factors.

Lead content was determined in 238 samples of 28 species of edible mushrooms collected from different sites in the province of Lugo (NW Spain) during 2005 and 2006. The hymenophore (H) and the rest of the fruiting body (RFB) were analysed separately. The analyses were carried out by an anodic stripping voltammetric technique using drop mercury as the working electrode. The highest mean lead contents (mg/kg dry weight) of 3.6 and 4.1, 3.0 and 2.2, 2.5 and 2.3, 2.4 and 2.3 were determined in Coprinus comatus, Agaricus campestris, Lepista nuda and Calvatia utriformis in hymenophore and the rest of fruiting bodies, respectively, while the lowest in Agaricus bisporus (0.35 in H and 0.54 in RFB) and Fistulina hepatica (0.41 in H and 0.50 in RFB). All mushroom species were bioexclusors of lead (BCF<1) in relation to the underlying soils. There were not statistically significant differences between lead levels in hymenophore and in the rest of the fruiting bodies. The lead concentrations were compared to literature data and levels set by legislation. It can be concluded that the consumption of these mushrooms can not be considered as a toxicological risk from lead content point of view, and they provide a nutritional requirement to the diet.

Acumulación de cromo en setas silvestres comestibles: factoresque influyen en su captación y repercusiones toxicológicas / Chromium accumulation in wild edible mushrooms: factors that influence its uptake and toxicological repercussions

La polución metálica medioambiental ha incrementado notablemente el interés por los hongos por ser captadores de metales pesados. Nutricionalmente, el cromo puede considerarse incluso un oligoelemento, pero en dosis excesivas es nocivo para la salud. Los objetivos planteados son la determinación del contenido de cromo en setas comestibles silvestres, el análisis estadístico de factores que influyen en su captación, y finalmente la evaluación del riesgo toxicológico derivado de su consumo. Para realizar este estudio, se recogieron 97 muestras de setas comestibles de 14 especies procedentes de dos zonas diferenciadas en razón de la mayor o menor contaminación antropogénica en la provincia de Lugo (Galicia, España). Considerando separadamente las porciones anatómicas, himenóforo y resto del carpóforo, fueron procesadas por digestión húmeda en medio ácido para analizar el contenido de cromo por Espectroscopia Óptica con Plasma acoplado inductivamente. Los datos obtenidos fueron tratados estadísticamente mediante el Programa SPSS. Como resultados, cabe destacar que la especie Tricholoma portentosumfue la que menor cantidad de cromo acumuló (0,77 ppm), tanto en el himenóforo (0,88 ppm) como en el resto del carpóforo (0,72ppm); por el contrario Agaricus campestris presentó el mayor contenido de cromo (4,86 ppm). El pH del suelo sólo afectó estadísticamente a la captación de cromo en el resto del carpóforo, dependiendo a su vez de los factores especie, tráfico y materia orgánica del suelo. Sólo se observaron diferencias estadísticamente significativas para los niveles de cromo según la parte anatómica para Boletus edulis y Boletus badius. Desde el punto de vista toxicológico, teniendo en cuenta la participación de las setas en la dieta, puede considerarse que su aporte de cromo, no supone riesgo para la saluddel consumidor (AU)

The environmental metallic pollution has increased notably the interest to the mushrooms for its accumulation capacity of heavy metals. From the nutritional point of view, chromium can be considered even a trace element, but in excessive dose is a toxic for the health. The objectives in this work are the determination of chromium content in wild edible mushrooms, the analysis of statistic factors that influence its uptake, and finally the evaluation of the toxicological risk derivative from its consumption. To carry out this study, 97 edible mushroom samples of 14 species from two differentiated zones in reason of great or smaller pollution in the province of Lugo (Galicia, Spain) were collected. The samples were divided in two anatomical portions, hymenophore and the rest of the fruit body, processed by wet digestion in the acid medium and analyzed its chromium content by Inductively Coupled Plasma-Optical Emission Spectrometer. The obtained data were treated statistically through the Program SPSS.As result, the specie, Tricholoma portentosum accumulated chromium in minor quantity (0.77 ppm), in the hymenophore (0.88ppm) as well as in the rest of the fruit body (0.72 ppm); in contrast, Agaricus campestris presented the highest concentration of chromium (4.86 ppm). Soil pH only affected statistically to the chromium uptake in the rest of the fruit body, depending at the same time on the factors specie, traffic and organic matter of the soil. Differences statistically significant only were observed in Boletus edulis and Boletus badius according to the anatomical part. From the toxicological point of view, taking into account the participation of the mushrooms in the human diet, it can be considered that its chromium contribution, it does not suppose risk for the health of the consumer (AU)

Removal of toxic metals from aqueous solutions by fungal biomass of Agaricus macrosporus.

Fungi such as Agaricus macrosporus show potential for the removal of heavy metals from aqueous solutions contaminated by zinc, copper, mercury, cadmium or lead. This study investigated biosorption of these metals by living or non-living biomass of A. macrosporus from an acid solution, an acid solution supplemented with potassium and phosphorus, and an alkaline solution. Uptake showed a pH-dependent profile. Maximum percentage uptake of all metals was found to occur at alkaline pH (Cu 96%, Pb 89%). With living biomass, metal biosorption was greater and faster in K/P-supplemented acid medium than in non-supplemented acid medium, with equilibrium reached within 15 min for all metals, and the highest percentage uptake being of cadmium (96%). In general, the greatest differences in biosorption capacity were seen for living biomass, between supplemented and non-supplemented acid medium; the smallest differences were between living and dead biomass in alkaline medium. These results support the potential utility of A. macrosporus for heavy metal removal.

Evaluation of heavy metal contents in co-composts of poultry manure with barley wastes or chestnut burr/leaf litter.

The presence of heavy metals in composts is a main cause of adverse effects on animal and human health, transmitted through the food chain from the soil, groundwater and plants. In this study, the contents of Zn, Cd, Pb and Cu present in co-composts of poultry manure (liquid or solid) with a co-composting material (barley wastes or chestnut burr/leaf litter) were assessed. A compost of solid manure was used as control because a compost cannot be obtained from the liquid manure. The original solid poultry manure showed a Zn content of 2134+/-75 mg/kg, exceeding the current legal limit in Spain of 1100 mg/kg. In the solid poultry manure co-compost with chestnut burr/leaf litter and barley wastes, Zn content decreased to 813+/-25 mg/kg and 883+/-37 mg/kg, respectively. The contents in heavy metals (Zn, Cd, Pb and Cu) of the co-composts were under the maximum limit permitted under the Spanish legislation, excepting for the Zn level in liquid poultry manure co-composted with chestnut burr/leaf litter.

Estudio de la contaminación por plaguicidas organofosforados y triazinas en leche procedente de diversas rutas de recogida / Study of organophosphorus and triazines pesticides contamination in milk from various withdrawal routes

La utilización de plaguicidas en las labores agrícolas y tratamientos ganaderos, parece hoy en día insustituible, pudiendo generar residuos en los alimentos. En este estudio se ha determinado la presencia en leche de plaguicidas que actualmente tienen un amplio uso, organofosforados y triazinas, y valorando la posible contaminación de las rutas de recogida de leche que ha de ser utilizada en una industria de transformación láctea. En total se han recogido 242 muestras procedentes de 15 rutas de recogida de la parte occidental de Asturias y oriental de la provincia de Lugo (Galicia). Para la determinación de estas sustancias se ha utilizado un cromatógrafo de gases con detector de nitrógeno-fósforo. Los porcentajes de aparición de los plaguicidas estudiados fueron: terbutilazina (6,20%), diclorvos (5,78%), simazina (4,96%), atrazina (4,96%), cumafos (2,06%), y metil paration (0,83%). Considerando estos resultados y comparando las diversas rutas de recogida, se detectó mayor presencia de triazinas en Galicia que en Asturias, y respecto a los organofosforados en las rutas pertenecientes a la costa frente a las de interior

The use of pesticides in agricultural labours and cattleman treatments seems today irreplaceable, being able to generate residues in the foods. In this study has been determined the presence in cow milk of pesticides that currently have a wide use, organophosphorous and triazines, and valuing the possible pollution of the routes of milk withdrawal that there has of be used in a milky transformation industry. In total, 242 samples have been collected originating from 15 withdrawal routes of the western part of Asturias and eastern of the province of Lugo (Galicia). For the determination of these substances, a gas chromatograph with a nitrogenphosphorous detector has been used. The percentages of appearance of the pesticides studied were: terbuthylazine (6.20%), dichlorvos (5.78%), simazine (4.96%), atrazine (4.96%), coumaphos (2.06%), and methyl parathion (0.83%). Considering these results and comparing the various withdrawal routes, was detected greater presence of triazines in Galicia than in Asturias and with respect to the organophosphorous in the routes belonging to the coast as compared to those of interior

Puesta a punto del método de extracción por diálisis difásica para el análisis de triazinas en leches maternizadas / Diphasic dialysis extraction method for the analysis of triazines in milk (infant formulas)

Las triazinas son uno de los grupos de herbicidas más frecuentemente utilizados en las labores agrícolas. Habitualmente su extracción se realiza mediante métodos líquidolíquido. El objetivo de este trabajo fue la puesta a punto del método de extracción de la diálisis difásica para análisis de las triazinas en leches maternizadas. Para ello se utilizó un agitador orbital y membranas de diálisis visking 20/32“, llegando a establecerse como condiciones ideales: temperatura, 34 ºC; velocidad de agitación, 200 rpm; disolvente de extracción, iclorometano, y tiempo de extracción, 4 h. La identificación de los herbicidas y la validación del método analítico siguiendo la normativa vigente se realizó utilizando un cromatógrafo de gases con detector de nitrógeno-fósforo. Los tiempos de retención y las recuperaciones obtenidas para cada una de las triazinas fueron: simazina 6,95 min y 75,3 %; atrazina 17,18 min y 116 % y terbutilazina 17,75 min y 88,7 %, res-pectivamente. A partir de los resultados obtenidos se puede concluir que es un buen método de extracción para el análisis de estos posibles contaminantes en leches maternizadas

Triazines are one of the groups of herbicides most frequently used in agricultural labor. Generally, their analyses were carried out with liquid to liquid extraction methods. The aim of this work was to set up diphasic dialysis as an extraction method for the analysis of triazines in milk (infant formulas). An orbital agitator and membranes of dialysis visking 20/32” were used, establishing the following as ideal conditions: temperature, 34 ºC; agitation speed, 200 rpm; extraction solvent, dichloromethane, and extraction time, 4 h. The identification of the herbicides and the validation of the analytical method continuing the outstanding regulation were carried out by using a gas chromatograph with nitrogenphosphorus detector. The retention times and the recoveries obtained for each herbicide from the triazines were: simazine, 16.95 min and 75.30 %; atrazine, 17.18 min and 116.00 % andterbutilazine, 17.75 min and 88.70 %, respectively. According to these results, we can conclude that it is a good extraction method for the analysis of these possible milk pollutants

Acumulación de metales pesados en macromicetos comestibles y factores que influyen en su captación / Macrofungi as potential bioremediation agent in compost material contaminated with heavy metals

Se presenta un estudio sobre la presencia de metales pesados (cadmio, mercurio, plomo, cobre y zinc) en 238 muestras de carpóforos pertenecientes a 28 especies comestibles de hongos silvestres en la provincia de Lugo. El método analítico para la determinación de metales ha sido la Voltamperometría de redisolución anódica. Se ha estudiado la incidencia de los siguientes factores en la acumulación de metales en los hongos: especie, ecología (micorrízicas, saprófitas terrícolas, saprófitas lignícolas y saprófitas cultivadas) y parte anatómica del carpóforo (himenóforo y resto del carpóforo). Las especies saprófitas terrícolas muestran las máximas concentraciones metálicas, siendo las más bajas las de las especies lignícolas y cultivadas. Individualmente las especies más relevantes han sido: Agaricus macrosporus para el cadmio, Boletus pinophillus, para el mercurio; Coprinus comatus y Lepista rauda para el plomo, Macrolepiota procesa para el cobre, y Calvatia utriformis y Lactarius deliciosus para el zinc. El himenóforo es la parte anatómica que muestra mayores niveles de metales. (AU)

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