Refinar búsqueda
Resultados 1-6 de 6
Evaluation of pesticide residues in fruits and vegetables from the Aegean region of Turkey and assessment of risk to consumers
2021
Kazar Soydan, Didem | Turgut, Nalan | Yalçın, Melis | Turgut, Cafer | Karakuş, Perihan Binnur Kurt
Pesticides may cause a potential risk to human health when applied in excess to control pests, diseases, and weeds in crop fields. In the current study, conducted in the Aegean region of Turkey from 2012 to 2016, a total of 3044 samples of 16 different commodities of fruits and vegetables were screened to identify pesticide residues and health risk to consumers posed by such residues was assessed. Results showed that 354 samples out of the total samples had higher maximum residue limit (MRL) values, while the MRL values were lower in 473 samples. In the study, residues of 64 different pesticides detected in 3044 samples in which 11.6% samples exceeded maximum residue limit (MRL) levels as compared with that of the approved MRL level by the Turkish authorities. Out of total samples, number of samples having high MRL level were as follows: 74 for chlorpyrifos (2.43%), 145 for azoxystrobin (3.8%), 112 for triadimenol (3.8%), 103 for carbendazim (3.4%), 98 for chlorpyrifos (3.2%), 94 for pyrimethanil (3.10%), 90 for cyprodinil (2.9%), 76 for fludioxonil (2.50%), 75 for indoxacarb (2.40%), 66 for imidacloprid (2.10%), and 60 for boscalid (1.90%). Residues of one, two, three, four, and even more than five pesticides were detected, respectively, in 16.1, 5.8, 2.8, 1, and 1.7% of the total test samples. The lowest estimated daily intake (EDI) values ranged from 3.57×10⁻³ to 8.98. The lower values of hazard quotient (HQ) were obtained in dried apricot, grape, and strawberry with the value of 0.01, although the HQ value in 32 out of 62 pesticides tested was found to be close to 0.
Mostrar más [+] Menos [-]Risk Assessment of 1,2,4-Triazole-Typed Fungicides for Groundwater Pollution Using Leaching Potential Indices
2021
Aliste, Marina | Pérez-Lucas, Gabriel | Garrido, Isabel | Fenoll, José | Navarro, Simón
The main objective of this study was to learn the leachability of three widely used triazole fungicides (flutriafol, myclobutanil and triadimenol) in clay-loam soil to assess the risk of groundwater pollution by means of leaching potential indices (LPIs). For this, sorption, degradation and leaching experiments were conducted in a lab to evaluate the behaviour of the fungicides in a typical semiarid Mediterranean soil (calcareous Regosol). The sorption study was carried out following the batch equilibrium method. The degradation test was performed in aerobic and dark conditions (21 °C) for 60 days. Finally, the leaching potential was assessed using disturbed soil columns. Samples of soil and water were analysed by HPLC-MS². Low adsorption in the soil (log KOC ≤ 2.5) was observed for the three fungicides. The half-lives ranged from 79 to 136 days for triadimenol and flutriafol, respectively, showing moderate to high persistence in soil. All fungicides were detected in leachates with percentages ranging from 12% (triadimenol) to 26% (myclobutanil) of the initial mass added. Concentrations found in total leachates (13, 17 and 23 µg L⁻¹ for triadimenol, flutriafol and myclobutanil, respectively) were in all cases higher than the maximum admissible concentration (0.1 µg L⁻¹) established by the EU for groundwater. In accordance with the screening indices used (GUS, RLPI, LIX and ELI), all fungicides behave as mobile or very mobile compounds. The findings suggest that the studied fungicides are candidates to pollute groundwater resources, mainly in areas with intensive yearly rainfall regimes.
Mostrar más [+] Menos [-]Solar photocatalysis as strategy for on-site reclamation of agro-wastewater polluted with pesticide residues on farms using a modular facility
2021
Garrido, Isabel | Fenoll, José | Flores, Pilar | Hellín, Pilar | Pérez-Lucas, Gabriel | Navarro, Simón
One of the consequences of phytosanitary treatments applied to crops is the generation of a great volume of agro-wastewater having pesticide residues. These pollutants can be considered a serious threat to the environment and human health due to their capacity to affect distant areas remaining for a long time after their application. We have assessed the degradation of five pesticides in agro-waste water produced in two farms by the cleaning pesticide containers and phytosanitary treatment equipment used in the farms. For this purpose, a pilot facility was installed in both farms and advanced oxidation treatments were conducted using natural sunlight by means of Na₂S₂O₈ and heterogeneous photocatalysis (TiO₂/Na₂S₂O₈). The remaining percentages obtained at the end of the experiments ranged from 5 to 90.1% for chlorantraniliprole, 5 to 82.3% for difenoconazole, 0.02 to 19.1% for metalaxyl, 1.4 to 74.4% for myclobutanil, and 0.3 to 61% for triadimenol. We observed a correlation between the higher remaining percentages and the total initial concentration of pollutant because of other commercial formulations applied in the farms. The results showed that this equipment could be used to eliminate or reduce the presence of pesticide residues in agro-waste water using an innovative facility installed in the farms and a renewable and economical source of energy (sunlight).
Mostrar más [+] Menos [-]Stereoselective metabolism and potential adverse effects of chiral fungicide triadimenol on Eremias argus
2020
Wang, Zikang | Tian, Zhongnan | Chen, Li | Zhang, Wenjun | Zhang, Luyao | Li, Yao | Diao, Jinling | Zhou, Zhiqiang
Reptiles are an important part of vertebrates and are the primitive terrestrial vertebrates. However, lots of reptile species are endangered or susceptible to extinction. It is no doubt that contaminants are one of the important reasons for the decline of the lizard population. In this study, the selective metabolism of triadimenol (TN) in the male Eremias argus lizards and the toxic effects of TN on lizards were studied. TN chiral isomers were separated and detected by HPLC-MS/MS system with Lux Cellulose-1 column. Tissue distribution experiments showed the existence of stereoselectivity biotransformation of TN enantiomers among organs in lizards, and RR-TN preferentially emerged over the other enantiomers. The antioxidant enzymes (SOD, CAT, GST) activities and MDA content assays demonstrated that TN induced oxidative stress in most organs, especially in the liver, and the histopathology analysis showed the severe liver and testis damage caused by 14-day continuous TN gavage. The reproductive effects of TN-induced reflected in the increased sex hormone testosterone. This research confirms that TN could induce hepatic and reproductive toxicity of E. argus lizard.
Mostrar más [+] Menos [-]Application of a biosorbent to soil: a potential method for controlling water pollution by pesticides
2016
Álvarez-Martín, Alba | Rodríguez-Cruz, M Sonia | Andrades, M Soledad | Sánchez-Martín, María J.
Different strategies are now being optimized to prevent water from agricultural areas being contaminated by pesticides. The aim of this work was to optimize the adsorption of non-polar (tebuconazole, triadimenol) and polar (cymoxanil, pirimicarb) pesticides by soils after applying the biosorbent spent mushroom substrate (SMS) at different rates. The adsorption isotherms of pesticides by three soils and SMS-amended soils were obtained and the adsorption constants were calculated. The distribution coefficients (K d) increased 1.40–23.1 times (tebuconazole), 1.08–23.7 times (triadimenol), 1.31–42.1 times (cymoxanil), and 0.55–23.8 times (pirimicarb) for soils amended with biosorbent at rates between 2 and 75 %. Increasing the SMS rates led to a constant increase in adsorption efficiency for non-polar pesticides but not for polar pesticides, due to the increase in the organic carbon (OC) content of soils as indicated by K OC values. The OC content of SMS-amended soils accounted for more than 90 % of the adsorption variability of non-polar pesticides, but it accounted for only 56.3 % for polar pesticides. The estimated adsorption of SMS-amended soils determined from the individual adsorption of soils and SMS was more consistent with real experimental values for non-polar pesticides than for polar pesticides. The results revealed the use of SMS as a tool to optimize pesticide adsorption by soils in dealing with specific contamination problems involving these compounds.
Mostrar más [+] Menos [-]Intra-annual trends of fungicide residues in waters from vineyard areas in La Rioja region of northern Spain
2016
Herrero-Hernández, Eliseo | Pose-Juan, Eva | Sánchez-Martín, María J. | Andrades, M Soledad | Rodríguez-Cruz, M Sonia
The temporal trends of fungicides in surface and ground water in 90 samples, including both surface waters (12) and ground waters (78) from an extensive vineyard area located in La Rioja (Spain), were examined between September 2010 and September 2011. Fungicides are used in increasing amounts on vines in many countries, and they may reach the water resources. However, few data have been published on fungicides in waters, with herbicides being the most frequently monitored compounds. The presence, distribution and year-long evolution of 17 fungicides widely used in the region and a degradation product were evaluated in waters during four sampling campaigns. All the fungicides included in the study were detected at one or more of the points sampled during the four campaigns. Metalaxyl, its metabolite CGA-92370, penconazole and tebuconazole were the fungicides detected in the greatest number of samples, although myclobutanil, CGA-92370 and triadimenol were detected at the highest concentrations. The highest levels of individual fungicides were found in Rioja Alavesa, with concentrations of up to 25.52 μg L⁻¹, and more than 40 % of the samples recorded a total concentration of >0.5 μg L⁻¹. More than six fungicides were positively identified in a third of the ground and surface waters in all the sampling campaigns. There were no significant differences between the results obtained in the four sampling campaigns and corroborated a pattern of diffuse contamination from the use of fungicides. The results confirm that natural waters in the study area are extremely vulnerable to contamination by fungicides and highlight the need to implement strategies to prevent and control water contamination by these compounds.
Mostrar más [+] Menos [-]