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Cumulative risk assessment of dietary exposure to triazole fungicides from 13 daily-consumed foods in China
2021
Cui, Kai | Wu, Xiaohu | Zhang, Ying | Cao, Junli | Wei, Dongmei | Xu, Jun | Dong, Fengshou | Liu, Xingang | Zheng, Yongquan
The agroeconomic benefits of the routine use of triazole fungicides on crops have been evident for more than 40 years. However, increasing evidence shows that residues of triazoles are ubiquitous in various foods and thus could pose a potential health risk to humans. We analyzed 3406 samples of 13 food commodities that were collected from markets in 9 regions across China, and assessed the health risk of both chronic and acute exposure to the triazoles for Chinese children (1–6 years old) and the general population. Among all samples, 55.52% had triazoles in concentrations of 0.10–803.30 μg/kg, and 29.77% of samples contained a combination of 2–7 triazoles. Tebuconazole and difenoconazole were the most commonly found triazoles in the foods, being detected in 33.44% and 30.45% of samples, respectively. Chronic and acute cumulative risk assessment for total triazoles based on a relative potency factor method revealed that exposure to triazoles from these particular commodities was below the levels that might pose a health risk (chronic hazard index range, 5.90×10⁻⁷ to 1.83×10⁻³; acute hazard index range, 7.77×10⁻⁵ to 0.39, below 1). Notably, dietary exposure risk for children was greater than that for the general population—particularly for the acute intake of mandarin, grape, and cucumber (acute hazard index values of 0.35–0.39). Despite the low health risk, the potential hazards of exposure to triazoles should raise public concern owing to their ubiquitous presence in common foods and potential cumulative effects.
اظهر المزيد [+] اقل [-]Gating in grapevine: Relationship between application of the fungicide fludioxonil and circadian rhythm on photosynthesis
2009
Petit, Anne-Noëlle | Fontaine, Florence | Clement, Christophe | Vaillant-Gaveau, Nathalie
The aim of this study was to determine the impact of the fludioxonil (fdx) fungicide on the diurnal fluctuation in grapevine photosynthesis. Therefore, fdx treatment was performed at the end of flowering, at 8 am, 12 am or 7 pm. The study was performed in experimental field and several photosynthesis parameters were followed one day after treatment. Morning fdx treatment induced (i) a significant and simultaneous drop of both photosynthesis (Pn) and stomatal conductance between 8 am and 4 pm and (ii) an increase of intercellular CO2 concentration when compared to control plants. On the contrary, evening fdx treatment did not affect Pn whereas midday treatment caused Pn increase after 4 pm. These data suggest that (i) morning fdx treatment results in a non-stomatal limitation of Pn, (ii) midday treatment is more suitable to treat grapevine with fdx and (iii) a phenomenon of gating was noticed. The period of fdx spraying was an important parameter in stress response: the midday fdx treatment is more suitable to treat grapevine with fdx.
اظهر المزيد [+] اقل [-]Comparison of different stomatal conductance algorithms for ozone flux modelling
2007
Büker, P. | Emberson, L.D. | Ashmore, M.R. | Cambridge, H.M. | Jacobs, C.M.J. | Massman, W.J. | Müller, J. | Nikolov, N. | Novak, K. | Oksanen, E.
A multiplicative and a semi-mechanistic, BWB-type [Ball, J.T., Woodrow, I.E., Berry, J.A., 1987. A model predicting stomatal conductance and its contribution to the control of photosynthesis under different environmental conditions. In: Biggens, J. (Ed.), Progress in Photosynthesis Research, vol. IV. Martinus Nijhoff, Dordrecht, pp. 221-224.] algorithm for calculating stomatal conductance (gs) at the leaf level have been parameterised for two crop and two tree species to test their use in regional scale ozone deposition modelling. The algorithms were tested against measured, site-specific data for durum wheat, grapevine, beech and birch of different European provenances. A direct comparison of both algorithms showed a similar performance in predicting hourly means and daily time-courses of gs, whereas the multiplicative algorithm outperformed the BWB-type algorithm in modelling seasonal time-courses due to the inclusion of a phenology function. The re-parameterisation of the algorithms for local conditions in order to validate ozone deposition modelling on a European scale reveals the higher input requirements of the BWB-type algorithm as compared to the multiplicative algorithm because of the need of the former to model net photosynthesis (An).
اظهر المزيد [+] اقل [-]Relation between organophosphate pesticide metabolite concentrations with pesticide exposures, socio-economic factors and lifestyles: A cross-sectional study among school boys in the rural Western Cape, South Africa
2021
Molomo, Regina Ntsubise | Basera, Wisdom | Chetty-Mhlanga, Shala | Fuhrimann, Samuel | Mugari, Mufaro | Wiesner, Lubbe | Röösli, Martin | Dalvie, Mohamed Aqiel
Evidence on the relationship between lifestyle, socio-economic factors and pesticide exposure and urinary concentrations of organophosphate (OP) pesticide metabolites among children is generally incomplete. This study investigated the relationship between socio-economic factors and reported pesticide exposures and the sum of three urinary concentrations of dialkyl phosphate metabolites (DAP) among boys living in the rural areas of the Western Cape, South Africa. Data was collected during a cross-sectional study of 183 boys from three agricultural intense areas. Measurements included a questionnaire on socio-economic and pesticide exposures and urinary DAP concentrations. Most boys (70%) lived on farms with a median age of 12 years (range: 5.0–19.5 years). Children aged >14 years had lower DAP urine concentrations (median = 39.9 ng/ml; β = −68.1 ng/ml; 95% CI: −136.8, 0.6) than children aged 9 years and younger (median = 107.0 ng/ml). DAP concentrations also varied significantly with area, with concentrations in the grape farming area, Hex River Valley (median = 61.8 ng/ml; β = −52.1; 95% CI: −97.9, −6.3 ng/ml) and the wheat farming area, Piketberg (median = 72.4 ng/ml; β = −54.2; 95% CI: 98.8, −9.7 ng/ml) lower than those in the pome farming area, Grabouw (median = 79.9 ng/ml). Other weaker and non-significant associations with increased DAP levels were found with increased household income, member of household working with pesticides, living on a farm, drinking water from an open water source and eating crops from the vineyard and or garden. The study found younger age and living in and around apple and grape farms to be associated with increased urinary DAP concentrations. Additionally, there were other pesticide exposures and socio-economic and lifestyle factors that were weakly associated with elevated urinary DAP levels requiring further study. The study provided more evidence on factors associated to urinary DAP concentrations especially in developing country settings.
اظهر المزيد [+] اقل [-]Multi-omics analyses on the response mechanisms of ‘Shine Muscat’ grapevine to low degree of excess copper stress (Low-ECS)
2021
Chen, Mengxia | Fang, Xiang | Wang, Zicheng | Shangguan, Lingfei | Liu, Tianhua | Chen, Chun | Liu, Zhongjie | Ge, Mengqing | Zhang, Chuan | Zheng, Ting | Fang, Jinggui
Copper stress is one of the most severe heavy metal stresses in plants. Grapevine has a relatively higher copper tolerance than other fruit crops. However, there are no reports regarding the tolerance mechanisms of the ‘Shine Muscat’ (‘SM’) grape to a low degree of excess copper stress (Low-ECS). Based on the physiological indicators and multi-omics (transcriptome, proteome, metabolome, and microRNAome) data, 8 h (h) after copper treatment was the most severe stress time point. Nonetheless, copper stress was alleviated 64 h after treatment. Cu ion transportation, photosynthesis pathway, antioxidant system, hormone metabolism, and autophagy were the primary response systems in ‘SM’ grapevine under Low-ECS. Numerous genes and proteins, such as HMA5, ABC transporters, PMM, GME, DHAR, MDHAR, ARGs, and ARPs, played essential roles in the ‘SM’ grapevine's response to Low-ECS. This work was carried out to gain insights into the multi-omics responses of ‘SM’ grapevine to Low-ECS. This study provides genetic and agronomic information that will guide better vinery management and breeding copper-resistant grape cultivars.
اظهر المزيد [+] اقل [-]Investigation of long-term hazards of chemical weapon agents in the environment of Sardasht area, Iran
2022
Vaezihir, Abdorreza | Pirkhezranian, Asra | Sehati, Negar | Hosseinzadeh, Mohammad Reza | Salehi-Lisar, Seyed Yahya | Sanderson, Hans
The present study aimed to investigate the persistence and existence of chemical warfare agents (CWAs) and related dissipation products in the environment of Sardasht area, Iran. Three types of environmental samples including water, soil, and native local plant materials were collected and analyzed. Gas chromatography-mass spectrometry in the electron impact ionization mode has been developed for the separation, screening, identification, and qualification of chemicals after the sample preparation methods. The initial results revealed that no trace of related compounds or CWAs was detected in the soil and water samples. However, trace amounts of some degradation products of blistering agents like mustard gas (HD) and lewisite were found in a tree wood from a house subjected to chemical attack as well as in barley samples (a mixture of leaves and root) collected from an agricultural field in the area indicating chronic low exposure to the environment and people. In order to validate the applied extraction procedures, ethylene glycol was spiked to some of the samples including groundwater, surface soil, grape, and alfalfa plants. All the recoveries were in the range of 83.6–107.4% with the relative standard deviations varying from 4.9% to 12.4% (n = 3) successfully.
اظهر المزيد [+] اقل [-]Insight into how fertilization strategies increase quality of grape (Kyoho) and shift microbial community
2022
Li, Xunan | Chu, Changbin | Ding, Sheng | Wei, Huawei | Wu, Shuhang | Xie, Bing
Organic and bioorganic fertilizers were increasingly used for agricultural soil. However, little is known on what kind of organic fertilizer application strategies can promote grape production well and how appropriate fertilization strategies improve soil properties and shift microbial community. This study investigated the improvement in soil physicochemical properties as well as their relations with microbial community structure and grape quality under different fertilization strategies. Our results found that (bio)organic fertilizer (CF1, CF2, and BF) especially combined application of organic and bioorganic fertilization (CBF) had smaller effects on electrical conductivity (EC) and pH, while it improved soil nutrients including N, P, K, and organic matter (OM) well, thereby promoting the grape quality comparing to the group without any fertilizer (CK) and with chemical fertilizer (NPK). Especially, the concentrations of Cr, Hg, Zn, and Cu were reduced by 13.63%, 12.50%, 12.52%, and 11.75% in CBF, respectively. Additionally, CF1, CF2, and BF, especially CBF, optimized the communities’ composition and increased the abundance of some plant probiotics such as Solirubrobacter and Lysobacter. Nevertheless, excessive application of organic fertilizer derived from livestock manure could cause the accumulation of heavy metals such as Zn and Cu in soil and leaves, which could further influence the grape quality. Additionally, the structure of microbial communities was also changed possibly because some bacterial genera showed distinct adaptability to the stress of heavy metals or the utilization capacity of N, P, K, and OM. Our results demonstrated that combined application of organic and bioorganic fertilization showed a great influence on soil physicochemical properties, whose positive changes could further optimize microbial communities and facilitate the promotion of grape quality.
اظهر المزيد [+] اقل [-]Plant uptake and soil retention of radionuclides and metals in vineyard environments
2021
Gulan, Ljiljana | Stajic, Jelena M. | Milenkovic, Biljana | Zeremski, Tijana | Milić, Stanko | Krstic, Dragana
In most European countries, each adult citizen drinks on average more than 20 L of wine every year. Three popular wine-growing areas (Aleksandrovac, Topola, and Orahovac) in Serbia were studied in order to investigate the abundance and uptake of elements from vineyard soil to plants. The specific activities of radionuclides (²²⁶Ra, ²³²Th, ⁴⁰K, ¹³⁷Cs, and ⁷Be) were measured in soil, leaves, and grape berries. ²²⁶Ra and ²³²Th were positively correlated with silt and clay and negatively correlated with sand content in soil. Specific activities of natural radionuclides were also negatively correlated with soil pH and CaCO₃. Significant correlations of ⁴⁰K and ¹³⁷Cs with organic matter in soil were found. Concentrations of fifteen metals (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn, Fe, K, Na, Ca, Mg, and Hg) were also measured in soil samples as well as in grapevine leaves. Analyzed soils were rich in Ni, Cu, Co, Cr, and Cd. High concentrations of Cu were probably caused by long-term use of Cu-based fungicides. Cu was correlated with Fe and organic matter content in soil. Soil-to-plant transfer factors (TF) were calculated to estimate the uptake of radionuclides and metals. Correlations obtained via PCA enable distinction between the sites Aleksandrovac and Topola relative to Orahovac. The first principal component (PC1) accounting for 30.70% of the total variance correlated significantly with soil pH (H₂O), contents of CaCO₃, Na, Ca, ⁴⁰K, and ²²⁶Ra in soil, as well as with ²²⁶Ra, Na, Ca in plants and TFCₐ. The second principal component (PC2), with total variance of 17.21%, was mainly correlated with variables pertaining to Mg, Co, and Cr in the soil and TFK.
اظهر المزيد [+] اقل [-]Dissipation, residue, dietary, and ecological risk assessment of atrazine in apples, grapes, tea, and their soil
2021
Yuan, Longfei | Chai, Yida | Li, Congdi | Liu, Rong | Chen, Zenglong | Li, Li | Li, Wei | He, Yujian
Atrazine is one of the most used herbicides in China. It is a persistent organic pollutant but has been widely used on Chinese farmlands for a long time. To assess its dietary and ecological risks to human and environment, in this study, atrazine residues were extracted with acetonitrile and then plant samples were detected with gas chromatography coupled with mass spectrometry (GC-MS) and soil samples were determined with gas chromatography coupled with nitrogen-phosphorus detector (GC-NPD). The limit of quantification (LOQ) of the method was 0.01 mg/kg for all matrices. The recoveries ranged from 82.0 to 105.4% for plant samples and 75.6 to 85.6% for soil samples. The final residues of atrazine in all plant samples were lower than LOQ. Dietary risk assessment suggested that under good agricultural practices (GAP) conditions, intake of atrazine from apples, grapes, and tea would exhibit an acceptably low health risk on consumers. However, the final residues of atrazine in soil samples were <0.01–9.2 mg/kg, and the half-lives were 2.0–9.1 days. Based on the species sensitivity distribution (SSD) model, the potential affected fraction (PAF) of atrazine in soil samples ranges from 0.01 to 65.8%. Atrazine residues in 43.1% soil samples were higher than 0.11 mg/kg, which was the hazardous concentration for 5% of species (HC₅) of atrazine in soil. These results suggested that the ecological risks of atrazine in apples, grapes, and tea garden soil would exhibit a high risk on environmental species even under the same GAP conditions. This study could provide guidance for comprehensive risk assessment of atrazine properly used in apple, grape, and tea gardens.
اظهر المزيد [+] اقل [-]Removal of U(VI) from Aquatic Systems, Using Winery By-Products as Biosorbents: Equilibrium, Kinetic, and Speciation Studies
2015
Anagnostopoulos, Vasileios A. | Koutsoukos, P. G. (Petros G.) | Symeopoulos, Basil D.
Grape stalks, a low-cost agro-industrial by-product, were used for the first time as a biosorbent for the removal of uranium from aquatic systems. Basic operating conditions (effect of pH, biosorbent dose, uranium initial concentration, and kinetics) were investigated, and the sorption mechanism was explored. The proposed biosorbent’s efficiency to sequester uranium from different profile aquatic systems was assessed, as well as the potential uranium recovery. Biosoprtion performance increased progressively from pH 1.5 to 4.5, and uranium uptake was a rapid process, where film diffusion was the determining step. Maximum uptake ranged from 90 to 115 mg U(VI) g⁻¹at 15–33 °C, respectively. None of the commonly used adsorption models (Langmuir, Freundlich, Dubinin-Radushkevich) was able to describe the experimental isotherms, whereas the linear model seems to provide the best fit. Kinetic and thermodynamic data implied that both physical and chemical sorption are involved in the process. Species calculation experiments showed that only positively charged and uncharged uranium species can be retained on the biomass. Quantitative uranium recovery was achieved by mild desorbing agents at concentrations as low as 0.1 M. Therefore, grape stalks seem to be a promising biosorbent due to their high sequestration capacity even under high salinity and acidity conditions, low cost, and easy regeneration.
اظهر المزيد [+] اقل [-]