Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 349
Filtrar
Mais filtros

Intervalo de ano de publicação
1.
Food Chem Toxicol ; 190: 114832, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38908816

RESUMO

Rare Earth Elements (REEs) have been implicated in potential health effects. However, the health risk of REE exposure among tea drinkers in China remains poorly understood. This study aimed to characterize the concentration of REEs in different tea categories and evaluate the associated health risks for tea consumers in China. By analyzing the content of 16 REEs in 4326 tea samples from China, the exposure level of REEs to the general population was estimated. The content of these 16 REEs was similar across six types of tea, with oolong tea exhibiting the highest levels. The concentration of light rare earth elements (LREEs) in six types of tea was higher than that of heavy rare earth elements (HREEs). The daily mean and 95th percentile (P95) exposure to REEs from tea for the general population in China were 0.0328 µg/kg BW and 0.1283 µg/kg BW, respectively, which are significantly lower than the temporary acceptable daily dose (tADI). Our findings suggest that REEs from tea do not pose a known health risk to Chinese consumers.


Assuntos
Metais Terras Raras , Chá , Chá/química , Metais Terras Raras/análise , China , Medição de Risco , Humanos , Contaminação de Alimentos/análise , Exposição Dietética
2.
Environ Monit Assess ; 196(7): 596, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839676

RESUMO

The issue of soil acidification in tea plantations has become a critical concern due to its potential impact on tea quality and plant health. Understanding the factors contributing to soil acidification is essential for implementing effective soil management strategies in tea-growing regions. In this study, a field study was conducted to investigate the effects of tea plantations on soil acidification and the associated acid-base buffering capacity (pHBC). We assessed acidification, pHBC, nutrient concentrations, and cation contents in the top 0-20 cm layer of soil across forty tea gardens of varying stand ages (0-5, 5-10, 10-20, and 20-40 years old) in Anji County, Zhejiang Province, China. The results revealed evident soil acidification due to tea plantation activities, with the lowest soil pH observed in tea gardens aged 10-20 and 20-40 years. Higher levels of soil organic matter (SOM), total nitrogen (TN), Olsen phosphorus (Olsen-P), available iron (Fe), and exchangeable hydrogen (H+) were notably recorded in 10-20 and 20-40 years old tea garden soils, suggesting an increased risk of soil acidification with prolonged tea cultivation. Furthermore, prolonged tea cultivation correlated with increased pHBC, which amplified with tea stand ages. The investigation of the relationship between soil pHBC and various parameters highlighted significant influences from soil pH, SOM, cation exchange capacity, TN, available potassium, Olsen-P, exchangeable acids (including H+ and aluminum), available Fe, and available zinc. Consequently, these findings underscore a substantial risk of soil acidification in tea gardens within the monitored region, with SOM and TN content being key driving factors influencing pHBC.


Assuntos
Camellia sinensis , Monitoramento Ambiental , Nitrogênio , Solo , Solo/química , Camellia sinensis/química , Nitrogênio/análise , China , Concentração de Íons de Hidrogênio , Ecossistema , Fósforo/análise , Chá/química , Agricultura
3.
Environ Monit Assess ; 196(7): 656, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916777

RESUMO

Previous research on pesticides in green tea mainly focused on detection technology but lacked insights into pesticide use during cultivation. To address this gap, a survey was conducted among Rizhao green tea farmers. The survey results showed that most tea farmers were approximately 60 years old and managed small, scattered tea gardens (< 0.067 ha). Notably, tea farmers who had received agricultural training executed more standardized pesticide application practices. Matrine and thiazinone are the most used pesticides. A total of 16 types of pesticides were detected in the tested green tea samples, with 65% of the samples containing residues of at least one pesticide. Notably, higher levels of residues were observed for bifenthrin, cyfluthrin, and acetamiprid. The presence of pesticide residues varied significantly between seasons and regions. The risk assessment results indicated that the hazard quotient (HQ) values for all 16 pesticides detected in green tea were < 1, suggesting that these residue levels do not pose a significant public health concern.


Assuntos
Resíduos de Praguicidas , Praguicidas , Chá , Chá/química , Medição de Risco , Praguicidas/análise , Resíduos de Praguicidas/análise , Monitoramento Ambiental , Humanos , Fazendeiros , Agricultura , Camellia sinensis/química , Piretrinas/análise , China , Exposição Ocupacional/análise
4.
J Trace Elem Med Biol ; 84: 127454, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38669815

RESUMO

BACKGROUND: The perennial evergreen tea (Camellia sinensis) plant is one of the most popular nonalcoholic drinks in the world. Fertilizers and industrial, agricultural, and municipal activities are the usual drivers of soil contamination, contaminating tea plants with potentially toxic elements (PTEs). These elements might potentially accumulate to larger amounts in the leaves of plants after being taken up from the soil. Thus, frequent monitoring of these elements is critically important. METHODS: The present study intended to determine PTEs (Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb) in both tea leaves and infusions using ICP-OES. Various multivariate data analysis methods such as principal component analysis (PCA) and hierarchical cluster analysis (HCA) were employed to elucidate the potential sources of PTEs contamination, whether from anthropogenic activities or natural origins. Additionally, Pearson's correlation coefficient (PCC) was calculated to assess the relationships between the variables under study. RESULTS: The mean contents (mg/L) of all studied elements in tea infusions decreased in order Mn (150.59 ±â€¯1.66) > Fe (11.39 ±â€¯0.99) > Zn (6.62 ±â€¯0.89) > Cu (5.86 ±â€¯0.62) > Co (3.25 ±â€¯0.64) > Ni (1.69 ±â€¯0.23) > Pb (1.08 ±â€¯0.16) > Cr (0.57 ±â€¯0.09) > Cd (0.46 ±â€¯0.09) > Al (0.05 ±â€¯0.008), indicating that Mn exhibits the highest abundance. The mean concentration trend in tea leaf samples mirrored that of infusions, albeit with higher concentrations of PTEs in the former. The tolerable dietary intake (TDI) value for Ni and provisional tolerable monthly intake (PTMI) value for Cd surpassed the standards set by the WHO and EFSA. Calculated hazard index (HI < 1) and cumulative cancer risk (CCR) values suggest negligible exposure risk. CONCLUSION: Elevated levels of PTEs in commonly consumed tea products concern the public and regulatory agencies.


Assuntos
Chá , Chá/química , Análise Multivariada , Análise de Componente Principal , Carcinógenos/análise , Oligoelementos/análise , Humanos , Folhas de Planta/química , Camellia sinensis/química
5.
Sci Rep ; 14(1): 7381, 2024 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548964

RESUMO

The aim of the present work is to biosynthesize Chitosan nanoparticles (CTNp) using tea (Camellia sinensis) extract, with potent antimicrobial properties towards phytopathogens of rice. Preliminary chemical analysis of the extract showed that they contain carbohydrate as major compound and uronic acid indicating the nature of acidic polysaccharide. The structure of the isolated polysaccharide was analyzed through FTIR and 1H NMR. The CTNp was prepared by the addition of isolated tea polysaccharides to chitosan solution. The structure and size of the CTNp was determined through FTIR and DLS analyses. The surface morphology and size of the CTNp was analysed by SEM and HRTEM. The crystalinity nature of the synthesized nanoparticle was identified by XRD analysis. The CTNp exhibited the antimicrobial properties against the most devastating pathogens of rice viz., Pyricularia grisea, Xanthomonas oryzae under in vitro condition. CTNp also suppressed the blast and blight disease of rice under the detached leaf assay. These results suggest that the biosynthesized CTNp can be used to control the most devastating pathogens of rice.


Assuntos
Quitosana , Nanopartículas , Oryza , Quitosana/farmacologia , Nanopartículas/química , Chá , Extratos Vegetais/farmacologia
6.
Food Addit Contam Part B Surveill ; 17(2): 110-121, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38264900

RESUMO

Tea is one of the most common drinks, consumed for its pleasant flavour and several medicinal values. The present study aimed to determine the levels of trace elements in tea products marketed in the Saharan region of Ouargla, Algeria and to evaluate the health risks associated with its regular consumption in adults and infants. To this aim, 78 tea samples were analysed by Inductively Coupled Plasma - Mass Spectrometry. Tea samples appeared to be contaminated by lead (0.73 ± 0.08 µg g-1) and aluminium (0.22 ± 0.02 µg g-1). Cadmium, arsenic, mercury, cobalt, manganese, nickel, chromium, zinc and copper were also detected. General linear model analysis indicated that black tea samples were the most contaminated. Tea samples packed in tea bags were the most contaminated with arsenic, aluminium and manganese. The hazard index was 0.28 and 1.33 for adults and for infants, respectively, indicating adverse non-carcinogenic effects in infants.


Assuntos
Contaminação de Alimentos , Chá , Oligoelementos , Argélia , Humanos , Medição de Risco , Chá/química , Oligoelementos/análise , Contaminação de Alimentos/análise , Adulto , Lactente , Arsênio/análise , Metais Pesados/análise , Manganês/análise , Níquel/análise , Cobalto/análise , Chumbo/análise
7.
Biomed Chromatogr ; 38(1): e5771, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37942879

RESUMO

Prunella vulgaris has long been used in traditional medicine and is consumed as a tea in China. Here, the total phenolic and flavonoid concentrations of plants from different geographical regions were measured. It was found that the total phenolic acid concentration ranged from 4.15 to 8.82 g of gallic acid equivalent per 100 g of dry weight (DW), and the total flavonoid concentration was 4.67-7.33 g of rutin equivalent per 100 g DW. Antioxidant activities were measured using 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, and the results ranged from 73.47% to 94.43% and 74.54% to 93.39%, respectively, whereas α-glucosidase inhibition was between 75.31% and 95.49%. Correlation analysis showed that the total flavonoids in P. vulgaris had superior antioxidant and anti-α-glucosidase activities compared to the total phenolic compounds. The active components of P. vulgaris were analyzed using high-performance liquid chromatography quadrupole time-of-flight mass spectrometry combined with both classical molecular networking and feature-based molecular networking on the Global Natural Products Social platform, identifying 32 compounds, namely 14 flavonoids, 12 phenolic compounds, and 6 other chemical components. These results could provide useful information on the use of P. vulgaris as a functional tea.


Assuntos
Antioxidantes , Prunella , Antioxidantes/análise , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/química , Fenóis/química , Espectrometria de Massa com Cromatografia Líquida , Flavonoides/análise , Compostos Fitoquímicos , Chá/química
8.
Food Chem Toxicol ; 184: 114321, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38072213

RESUMO

Recently, mycotoxin risks in fermented tea have received high attention, but mycotoxin transfer rates from tealeaf to infusion during brewing were rarely considered. In addition, the assessment data (i.e., mycotoxin occurrences and tea consumption) in previous assessments were usually limited. Here, a comprehensive and cumulative risk assessment of aflatoxins and ochratoxin A was performed using a tea assessment model, by which mycotoxin transfer rates were included and the assessment data were collected worldwide. By 10 times of brewing, the aflatoxin transfer rate was only 2.94% and OTA was 63.65%. Besides the extreme case, hazard quotients (HQs) from all consumers were lower than the threshold of 1.0, indicating no noncarcinogenic risk; the P95 cumulative margin of exposure (1/MoET) values were 2.52E-04 (30-39 years of age) and 2.42E-04 (≥50 years of age) for two high exposure groups under the upper bound scenario, which a little higher than the carcinogenic risk threshold of 1.00E-04. Notably, the P95 cumulative 1/MoET values (3.24E-03 -7.95E-03) by food assessment model were ten times higher than those of by tea assessment model. The comparative results showed that mycotoxin dietary risks on tea consumption by food assessment model were much overestimated. The result of this study indicated that the contaminants transfer rates should be considered for risk assessment on tea consumption in future work.


Assuntos
Aflatoxinas , Micotoxinas , Ocratoxinas , Aflatoxinas/toxicidade , Exposição Dietética , Contaminação de Alimentos/análise , Micotoxinas/toxicidade , Micotoxinas/análise , Medição de Risco , Chá
9.
Biol Trace Elem Res ; 202(1): 387-396, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37127783

RESUMO

Tea is the world's most common drink after water, and the world's annual sales exceed $43 billion, of which more than $11 billion is green tea (Camellia sinensis (L.)). Increasing evidence continues to show that green tea consumption and its ingredients have a variety of potential health benefits. The aim of the study was to control and assess the toxicological risk (TRA) of three heavy metals (As, Pb, and Cd) in infusions of green tea (n = 12) from Polish markets. We applied the method of inductive coupled plasma mass spectrometry (ICP-MS) to determine the selected heavy metal and designed a specific toxicological risk assessment with three crucial tiers. The first tier of our strategy was to determine the elements investigated (heavy metal impurities, µg/L). The second step was to estimate the weekly intake of green tea infusions (µg/week) based on weekly consumption. The third tier was to estimate the weekly intake per weight (µg/L/week/bw), based on the average weekly intake of green tea infusion per adult compared to the provisional weekly intake (PTWI) established by the FAO/WHO Joint Food Additives Expert Committee (JECFA). The levels of the investigated heavy metals occur at different levels in all of the investigated green tea infusions. The heavy metal profile indicated that As (0.0721-10.585 µg/L), Pb (0.386-1.695 µg/L), and Cd (0.126-0.346 µg/L) were present in all samples. Basic analysis of general content shows that As (average = 0.325 µg/L) was at a level similar to Cd (average = 0.214 µg/L). Surprisingly, the Pb content (average 0.891 µg/L) was approximately 2.75-4 times higher than that of As and Cd, respectively. The application of our proposed safety assessment methodology (three tiers) provides satisfactory results for regulatory purposes. The evaluation of the investigated heavy metals in all products analysed from green tea samples (infusions) showed that there were no health hazards to consumers due to weekly exposure. The results indicated that after drinking green tea infusions from Polish markets, the amount of investigated elements in weekly doses does not represent any health risks to consumers.


Assuntos
Camellia sinensis , Metais Pesados , Humanos , Adulto , Camellia sinensis/química , Chá/química , Cádmio/análise , Polônia , Chumbo/análise , Metais Pesados/análise , Medição de Risco
10.
Molecules ; 28(21)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37959765

RESUMO

Natural products and their analogues have contributed significantly to treatment options, especially for anti-inflammatory and infectious diseases. Thus, the primary objective of this work was to compare the bioactivity profiles of selected medicinal plants that are historically used in folk medicine to treat inflammation and infections in the body. Chemical HPTLC fingerprinting was used to assess antioxidant, phenolic and flavonoid content, while bioassay-guided HPTLC was used to detect compounds with the highest antibacterial and anti-inflammatory activities. The results of this study showed that green tea leaf, walnut leaf, St. John's wort herb, wild thyme herb, European goldenrod herb, chamomile flower, and immortelle flower extracts were strong radical scavengers. Green tea and nettle extracts were the most active extracts against E. coli, while calendula flower extract showed significant potency against S. aureus. Furthermore, green tea, greater celandine, and fumitory extracts exhibited pronounced potential in suppressing COX-1 activity. The bioactive compounds from the green tea extract, as the most bioactive, were isolated by preparative thin-layer chromatography and characterized with their FTIR spectra. Although earlier studies have related green tea's anti-inflammatory properties to the presence of catechins, particularly epigallocatechin-3-gallate, the FTIR spectrum of the compound from the most intense bioactive zone showed the strongest anti-inflammatory activity can be attributed to amino acids and heterocyclic compounds. As expected, antibacterial activity in extracts was related to fatty acids and monoglycerides.


Assuntos
Produtos Biológicos , Plantas Medicinais , Antioxidantes/farmacologia , Antioxidantes/química , Plantas Medicinais/química , Cromatografia em Camada Fina/métodos , Staphylococcus aureus , Escherichia coli , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antibacterianos/farmacologia , Antibacterianos/química , Anti-Inflamatórios/farmacologia , Bioensaio , Chá
11.
J Agric Food Chem ; 71(48): 19045-19053, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37982559

RESUMO

Pyrrolizidine alkaloids (PAs) have been detected in tea and can threaten human health. However, the specific source of PAs in tea is still unclear. Here, 88 dried tea products collected from six major tea-producing areas in Anhui Province, China, were analyzed. The detection frequency was 76%. The content of total PAs in dried tea was between 1.1 and 90.5 µg/kg, which was all below the MRL recommended by the European Union (150 µg/kg). In the Shexian tea garden, PAs in the weeds and weed rhizospheric soil around tea plants and the fresh tea leaves were analyzed. Intermedine (Im), intermedine-N-oxide (ImNO), and jacobine-N-oxide (JbNO) were transferred through the weed-to-soil-to-tea route into the fresh tea leaves; only Im and ImNO were detected in dried tea samples. Potential risk of the total PAs in the tea infusion was assessed according to the margin of exposure method, and it might be a low concern for public health.


Assuntos
Camellia sinensis , Alcaloides de Pirrolizidina , Humanos , Alcaloides de Pirrolizidina/análise , Plantas Daninhas , Chá , Medição de Risco , Óxidos
12.
Gen Dent ; 71(6): 61-67, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37889246

RESUMO

This study aimed to use spectrophotometry to assess the color stability of composite resins polished with different polishing techniques and scanning electron microscopy (SEM) to evaluate the surface micromorphology of the specimens. In this in vitro experimental study, a total of 96 disc-shaped specimens were fabricated from microfilled (Renamel Microfill, shade SB3) and nanohybrid (Estelite Sigma Quick, shade BW) composite resins in bright white shades (n = 48). Each group was randomized into 1 control and 2 experimental subgroups (n = 16): no polishing (control), polishing with aluminum oxide discs (experimental), or polishing with diamond-impregnated spiral wheels (experimental). In each subgroup, half of the specimens were immersed in a coffee solution and the other half in a tea solution for 48 hours after finishing (control) or polishing (experimental). Spectrophotometry was used to measure the color of the specimens at baseline, after finishing, after polishing (experimental groups only), and after immersion in tea and coffee. The surface micromorphology of a randomly selected specimen from each subgroup was assessed under SEM. The color change (ΔE*) of the specimens between measurements was calculated and analyzed using 1-way, 2-way, and 3-way analyses of variance (ANOVAs) and the Tukey test. Both tea and coffee caused significant color change in the composite resin specimens, with specimens immersed in coffee undergoing significantly greater color change than those immersed in tea (P < 0.001; 2-way ANOVA). The nanohybrid composite specimens polished with polishing discs had a significantly greater color change than nanohybrid specimens polished with spiral wheels (P = 0.041). The Tukey test revealed that there was no overall significant difference between the 2 polishing techniques (P = 0.505), but both of these subgroups exhibited a significantly lower color change than the control group (P < 0.001). In general, SEM did not reveal substantial differences between the 2 polishing techniques, but specimens polished by spiral wheels appeared to have a smoother surface. All polished specimens demonstrated clinically acceptable mean color change values (ΔE* < 3.5). The type of coloring agent had a greater effect on color stability than either the polishing technique or type of composite resin, with coffee causing a greater color change than tea.


Assuntos
Café , Resinas Compostas , Humanos , Resinas Compostas/uso terapêutico , Espectrofotometria , Chá , Propriedades de Superfície , Teste de Materiais , Cor , Polimento Dentário/métodos
13.
Rocz Panstw Zakl Hig ; 74(3): 275-282, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37698111

RESUMO

Introduction: Coffee and tea are some of the most popular beverages in the world. Herbal infusions are also growing in popularity. Much attention is being paid to the effects of these beverages on the body and human health. Objective: The aim of the study was to analyse the consumption of coffee, tea and herbal infusions in terms of selected socioeconomic and lifestyle factors, as well as the frequency of beverages consumption in the study group. Materials and methods: The study involved 508 adult respondents, including 404 females and 104 males aged over 18 years. An online survey questionnaire was used, consisting of questions on socioeconomic data, lifestyle, height and weight, and frequency of consumption of coffee, tea and herbal infusions. Statistical analysis of the results was performed using Statistica 13.3 software, and statistical significance was assumed at the p≤0.05 level. Results: The beverages most often consumed by the adults was tea (90.2% of the respondents), followed by coffee (81.5%), the least frequently chosen beverage was herbal infusion (48%). The largest percentage of adults consuming coffee were: persons aged 18-29 (p=0.012), with higher education (p=0.010), living in cities over 500,000 inhabitants (p=0.048) or having permanent employment (p<0.001). In the case of tea consumption, significantly the largest percentage of adults concerned: women (p<0.001), persons with low physical activity (p=0.003) or good/very good self-dietary assessment (p<0.001). Significantly the largest percentage of adults consuming herbal infusions were: women (p<0.001), persons aged 18-29 (p=0.031) or with higher education (p<0.001). Gender was not a factor differentiating the frequency of consumption of the analyzed beverages in study group. Conclusions: The consumption of coffee, tea and herbal infusions is determined by several socio-demographic factors. Coffee was chosen more often by young people with an active professional life in large cities, which is probably related to the availability of this beverage in offices as well as in takeaway cafes.


Assuntos
Bebidas , Café , Adulto , Feminino , Humanos , Masculino , Cidades , Exercício Físico , Chá
15.
Food Chem ; 427: 136673, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37364316

RESUMO

Traceability and authentication of protected designation of origin (PDO) tea is an important prerequisite to safeguard its production and distribution system. Here, indicator displacement array (IDA) sensors consisting of natural anthocyanidins and edible metal ions were developed to authenticate PDO and non-PDO Longjing from different origins. Five IDA elements were selected for constructing sensors, achieved by an indicator displacement reaction after adding epigallocatechin gallate solution. The obtained sensors were subsequently used for real tea samples. Unsupervised algorithms were used for data exploration among PDO and non-PDO teas. The supervised support vector machine (SVM) model further achieved accurate authentication of PDO and non-PDO Longjing with a correct classification rate of 100% for the 26 validated samples. The developed IDA sensor thus achieves accurate authentication of PDO tea in a hazard-free and cost-efficient way, providing a useful tool for origin authentication of other agricultural products.


Assuntos
Colorimetria , Chá , Análise Custo-Benefício , Antocianinas
16.
Compr Rev Food Sci Food Saf ; 22(4): 3130-3150, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37195216

RESUMO

Tea polyphenols (TPs) are important secondary metabolites in tea and are active in the food and drug industry because of their rich biological activities. In diet and food production, TPs are often in contact with other food nutrients, affecting their respective physicochemical properties and functional activity. Therefore, the interaction between TPs and food nutrients is a very important topic. In this review, we describe the interactions between TPs and food nutrients such as proteins, polysaccharides, and lipids, highlight the forms of their interactions, and discuss the changes in structure, function, and activity resulting from their interactions.


Assuntos
Polifenóis , Chá , Chá/química , Polifenóis/química , Polissacarídeos/química , Antioxidantes/química , Nutrientes
17.
Molecules ; 28(9)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37175212

RESUMO

Tea (Camellia sinensis) is the second most consumed beverage worldwide, playing a key role in the human diet. Tea is considered a healthy drink, as its consumption has been linked to a lower risk of cardiovascular disease-related events and death, stroke, metabolic syndrome and obesity. However, several studies have shown that C. sinensis is a hyperaccumulator of Al and other elements that are considered potentially toxic. In the present study, the contents of 15 elements (both essential and toxic) were determined for the first time in tea leaves collected in tea gardens located in six different European countries and processed to provide black and green tea. The results showed that Al was the major toxic element detected, followed by Ni, Cr, Pb, As, Cd, Ag, and Hg. Essential elements were detected in the order of Mn, Fe, Zn, Cu, Co, and Se. Statistically significant correlations (p < 0.05) were found in the distribution of some elements, highlighting mechanisms of synergic or antagonist interaction. Multivariate analysis revealed that geographical origin was the main driver in clustering the samples, while the different treatment processes (black or green) did not significantly affect the contents of elements in the leaves. The estimation of potential non-carcinogenic risk revealed no risk for the consumption of European teas for consumers in terms of potentially toxic elements.


Assuntos
Camellia sinensis , Mercúrio , Humanos , Chá , Bebidas , Medição de Risco
18.
Environ Geochem Health ; 45(7): 5323-5341, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37131113

RESUMO

Dashan Village area is one of the representative areas in China with high selenium concentration in the natural environment. A total of 133 topsoil samples have been collected in the Dashan Village area to explore the potential toxic elements (PTEs) background concentrations in soils under different land-use types for a comprehensive PTEs risk assessment (arsenic, cadmium, chromium, copper, mercury, nickel, lead, selenium and zinc). The results show that the geometric mean concentrations of As, Cr, Cu, Hg, Ni, Pb, Se and Zn found in the soil of the Dashan Village area were lower than the control standard for soil contamination risk in agricultural land. However, the geometric mean concentrations of Cd exceeded their corresponding standard values. For different land-use types, geometric mean concentrations of As, Cd, Cu, Hg, Ni and Pb in the arable soils were higher than in woodland soils and tea garden soils. Based on the potential ecological risk assessment, the woodland, arable and tea garden were at low-risk levels. Cadmium posed the highest ecological risk, while the other PTEs were of low risk in soils. Multiple statistical analyses and geostatistical analysis indicated that the concentrations of Cr, Ni, Pb, Cu, Zn and Se originated mainly from natural sources, while the concentrations of Cd, As and Hg could be influenced by anthropogenic activities. These results provide scientific support for the safe utilization and ecological sustainability of selenium-rich land resources.


Assuntos
Mercúrio , Metais Pesados , Selênio , Poluentes do Solo , Solo , Metais Pesados/toxicidade , Metais Pesados/análise , Cádmio/análise , Selênio/análise , Cobre/análise , Chumbo/análise , Mercúrio/análise , Medição de Risco , China , Chá , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Monitoramento Ambiental/métodos
19.
Food Chem ; 420: 136103, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37040686

RESUMO

Black tea samples (390) collected from local markets situated in different locations of India were monitored for the residues of 386 pesticides using QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) based extraction and analysis by gas and liquid chromatography tandem mass spectrometry (GC-MS/MS and LC-MS/MS). Residues of seventeen pesticides were detected, of which propargite, cypermethrin, and novaluron showed the highest % positive detections. A comparison of the concentrations of the detected pesticide residues with the available national and international maximum residue limits (MRLs) showed that seven samples exceeded the Indian MRLs while no sample was found to exceed the CODEX MRLs. The risk due to the detected pesticide levels evaluated in terms of hazard quotient (HQ) and hazard index (HI) was found to be very low (<1), suggesting that the pesticide residues in the tea were safe for consumption by Indian adults and children.


Assuntos
Camellia sinensis , Resíduos de Praguicidas , Praguicidas , Criança , Humanos , Praguicidas/análise , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , Chá/química , Contaminação de Alimentos/análise , Medição de Risco
20.
J Agric Food Chem ; 71(16): 6434-6444, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37058117

RESUMO

The phthalate esters (PAEs) have become ubiquitous pollutants. In the present work, we investigated their pollution on teas. Dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DiBP), di-n-butyl phthalate (DBP), and di-(2-ethyl) hexyl phthalate (DEHP) were detected in all fresh tea leaves with DBP being the major congener of PAEs in teas followed by DiBP and DEHP. Seasonal variation, spatial distribution difference, correlationship of environmental factors, and potential health risks of PAEs were analyzed. The PAEs content in one bud and two leaves was lower than that in upper mature leaves in tea plants. The PAEs content in fresh tea leaves was the lowest in spring, while it was high in autumn and winter. The correlation analysis results showed that PAEs had significantly negative correlation with ambient air temperature, while it was positively correlated with the air quality index. PAEs analysis of spring tea in Anhui and Zhejiang provinces further indicated that the factor of provincial regions had little impact on the PAEs pollution level in tea. By contrast, the different environmental areas significantly affected PAE pollution, especially the agricultural areas. The human daily intake-based (13 g/day) risk assessment indicated that both the carcinogenic and non-carcinogenic risks (1.76 × 10-7-6.12 × 10-7) of PAEs via tea consumption were acceptable, with the estrogen equivalence (1.60-6.29 ng E2/kg) being at a medium level. This study provides significant information for pollution control and risk assessment of PAEs in Chinese tea production.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Humanos , Ésteres/análise , Ácidos Ftálicos/análise , Dibutilftalato/análise , Medição de Risco , Chá , China
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA