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1.
Anal Bioanal Chem ; 416(2): 431-438, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37982846

RESUMO

This study reports a novel analytical approach for the simultaneous determination of ethylene-thiourea (ETU) and propylene-thiourea (PTU) in fruits and vegetables by (reverse phase) high-performance liquid chromatography (HPLC) coupled to inductively coupled plasma-tandem mass spectrometry (ICP-QQQMS or ICP-MS/MS). A baseline separation of ETU and PTU was achieved in less than 5 min. A robust method validation by using the accuracy profile approach was performed by carrying out four measurement series in duplicate at six different levels over a timespan of 4 weeks (different days). The recovery factors ranged from 87 to 101% for ETU and from 98 to 99% for PTU (depending on the spiking level). The coefficient of variation in terms of repeatability (CVr) ranged from 1 to 4.7% for ETU and from 1.8 to 3.9% for PTU (depending also on the analyte level) while the coefficient of variation in terms of intermediate reproducibility (CVR) ranged from 3.4 to 10% for ETU and from 1.8 to 10.8% for PTU. The limit of quantification was 0.022 mg kg-1 (wet weight) for ETU and 0.010 mg kg-1 (ww) for PTU. This novel approach was proved to be highly robust and suitable for the determination of ETU and PTU in foodstuffs of vegetal origin.


Assuntos
Etilenotioureia , Tioureia , Tioureia/análise , Etilenotioureia/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Reprodutibilidade dos Testes , Etilenos
2.
JAMA Netw Open ; 6(5): e2311908, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37145599

RESUMO

Importance: Due to the amount of iodine 131 released in nuclear tests and its active uptake by the thyroid, differentiated thyroid carcinoma (DTC) is the most serious health risk for the population living near sites of nuclear tests. Whether low doses to the thyroid from nuclear fallout are associated with increased risk of thyroid cancer remains a controversial issue in medicine and public health, and a misunderstanding of this issue may be associated with overdiagnosis of DTCs. Design, Setting, and Participants: This case-control study was conducted by extending a case-control study published in 2010 that included DTCs diagnosed between 1984 and 2003 by adding DTCs diagnosed between 2004 and 2016 and improving the dose assessment methodology. Data on 41 atmospheric nuclear tests conducted by France between 1966 and 1974 in French Polynesia (FP) were assessed from original internal radiation-protection reports, which the French military declassified in 2013 and which included measurements in soil, air, water, milk, and food in all FP archipelagos. These original reports led to an upward reassessment of the nuclear fallout from the tests and a doubling of estimates of the mean thyroid radiation dose received by inhabitants from 2 mGy to nearly 5 mGy. Included patients were diagnosed from 1984 to 2016 with DTC at age 55 years or younger and were born in and resided in FP at diagnosis; 395 of 457 eligible cases were included, and up to 2 controls per case nearest by birthdate and matched on sex were identified from the FP birth registry. Data were analyzed from March 2019 through October 2021. Exposure: The radiation dose to the thyroid gland was estimated using recently declassified original radiation-protection service reports, meteorological reports, self-reported lifestyle information, and group interviews of key informants and female individuals who had children at the time of these tests. Main Outcomes and Measures: The lifetime risk of DTC based on Biological Effects of Ionizing Radiation (BEIR) VII models was estimated. Results: A total of 395 DTC cases (336 females [85.1%]; mean [SD] age at end of follow-up, 43.6 [12.9] years) and 555 controls (473 females [85.2%]; mean [SD] age at end of follow-up, 42.3 [12.5] years) were included. No association was found between thyroid radiation dose received before age 15 years and risk of DTC (excess relative risk [ERR] per milligray, 0.04; 95% CI, -0.09 to 0.17; P = .27). When excluding unifocal noninvasive microcarcinomas, the dose response was significant (ERR per milligray, 0.09; 95% CI, -0.03 to 0.02; P = .02), but several incoherencies with the results of the initial study reduce the credibility of this result. The lifetime risk for the entire FP population was 29 cases of DTC (95% CI, 8-97 cases), or 2.3% (95% CI, 0.6%-7.7%) of 1524 sporadic DTC cases in this population. Conclusions and Relevance: This case-control study found that French nuclear tests were associated with an increase in lifetime risk of PTC in FP residents of 29 cases of PTC. This finding suggests that the number of thyroid cancer cases and the true order of magnitude of health outcomes associated with these nuclear tests were small, which may reassure populations of this Pacific territory.


Assuntos
Adenocarcinoma , Cinza Radioativa , Neoplasias da Glândula Tireoide , Criança , Humanos , Feminino , Pessoa de Meia-Idade , Adolescente , Cinza Radioativa/efeitos adversos , Estudos de Casos e Controles , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/etiologia , Risco , Adenocarcinoma/complicações , Polinésia/epidemiologia
3.
Anal Bioanal Chem ; 415(16): 3093-3110, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37127735

RESUMO

Due to agricultural runoff, pesticides end up in aquatic ecosystems and some accumulate in marine bivalves. As filter feeders, bivalves can accumulate high concentrations of chemicals in their tissue representing a potential risk to the health of human and aquatic ecosystems. So far, most of the studies dealing with pesticide contamination in marine bivalves, for example, in the French Atlantic and English Channel coasts, have focused on the old generation of pesticides. Only a few investigated the newly emerging pesticides partly due to methodological challenges. A better understanding of the most sensitive and reliable methods is thus essential for accurately determining a wide variety of environmentally relevant pesticides in marine bivalves. The review highlighted the use of more environmentally friendly and efficient materials such as sorbents and the "quick easy cheap effective rugged safe" extraction procedure to extract pesticides from bivalve matrices, as they appeared to be the most efficient while being the safest. Moreover, this method combined with the high-resolution mass spectrometry (MS) technique offers promising perspectives by highlighting a wide range of pesticides including those that are not usually sought. Finally, recent developments in the field of ultra-high-performance liquid chromatography coupled to MS, such as two-dimensional chromatography and ion mobility spectrometry, will improve the analysis of pesticides in complex matrices.


Assuntos
Bivalves , Resíduos de Praguicidas , Praguicidas , Animais , Humanos , Praguicidas/análise , Resíduos de Praguicidas/análise , Ecossistema , Espectrometria de Massas em Tandem/métodos , Bivalves/química
4.
Mar Pollut Bull ; 192: 114988, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37216876

RESUMO

Biomarkers involved in detoxification process (GST), oxidative stress (SOD and MDA), immune response (Laccase) and neurotoxic disorders (AChE) were analysed in Pacific oysters and blue mussels collected from 4 locations within the Pertuis sea (France). Seasonal variations of total pesticide mean concentrations were found in seawater with metolachlor being the main pesticide measured (up to 32 ng/L). The majority of pesticide concentrations in sediment were below the LOD. Seasonal contamination differences were evidenced for chlortoluron, especially in mussels where concentrations reached 16 ng/g (wet weight) during the winter, in the Charente estuary, but no relationships with any of the biomarkers selected arisen. Actually, low concentrations of alpha-, beta-BHC and alachlor were correlated to GST activity, and low levels of hexachlorobenzene were linked to the AChE activity and MDA content in oysters. In mussels, low concentrations of methylparathion, parathion and beta-BHC were correlated to laccase.


Assuntos
Mytilus edulis , Praguicidas , Poluentes Químicos da Água , Animais , Praguicidas/análise , Estuários , Estações do Ano , Lacase , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Biomarcadores
5.
Food Chem ; 395: 133573, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-35777208

RESUMO

A screening method was developed for the multi-residue analysis of pesticides in baby foods using QuEChERS and UHPLC-Q-TOF. For sample preparation, the two-buffered versions of QuEChERS and different purification procedures were studied. False negatives and false positives were determined using different thresholds mentioned in the literature on the retention time and accurate mass measurement detection criteria. To reach unequivocal identification, the fragmentation spectra of the pesticides were used. The information-dependant-acquisition (IDA) mode was optimized with a precursor-inclusion list (PIL) to limit the loss of MS/MS data. Then, the experimental fragmentation spectra were compared to those included in a homemade library, by assessing different MS/MS algorithms and similarity scores. The optimised method was validated according to SANTE/11312/2021 guidelines. 95% and 73% of the pesticides presented a screening detection limit (SDL) and a limit of identification (LOI) ≤ 0.1 mg.kg-1. One plasticizer was found in the investigated samples by a suspect-screening approach.


Assuntos
Resíduos de Praguicidas , Praguicidas , Algoritmos , Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Alimentos Infantis/análise , Resíduos de Praguicidas/análise , Praguicidas/análise , Espectrometria de Massas em Tandem , Verduras/química
6.
Artigo em Inglês | MEDLINE | ID: mdl-35724341

RESUMO

European and French populations are overexposed to cadmium (Cd) through their foods. The risk of increased cadmium exposure for consumers needs to be limited by reduced maximum limits (ML) for novel foodstuffs such as edible seaweed in France. The objective was to derive a low and protective cadmium concentration in edible seaweeds to limit cadmium overexposure in consumers. To do so, we applied a probabilistic approach to the data collected on French seaweed consumers, taking into account other sources of exposure for cadmium. This approach led to the identification of a cadmium concentration which should ensure that the seaweed-consuming population does not exceed the tolerable daily intake (TDI) of cadmium according to a probability of cases, when simultaneously exposed to other cadmium dietary sources. Considering the 5% of the population exceeding TDI, the estimated ML is equal to 0.35 mg Cd kg-1 dry matter of seaweed as an unprocessed food with a 95% confidence interval of [0.18,1.09]. The proposed approach is generic and could be applied to other relevant food/substance pairs when considering the setting of MLs in the regulatory system. It ensures better protection of consumer health.


Assuntos
Cádmio , Alga Marinha , Cádmio/análise , Dieta , Contaminação de Alimentos/análise , Medição de Risco , Verduras
7.
Food Chem ; 386: 132871, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35381542

RESUMO

A qualitative screening high resolution mass spectrometry method was developed and validated according to the EU SANTE/12682/2019 guidelines for the analysis of 204 pesticides in seven commercial bivalve species spiked at three concentrations (0.01, 0.05 and, 0.1 mg.kg-1). Samples were extracted using QuEChERS and analysed using ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry. The QuEChERS method was optimised by the Taguchi Orthogonal Array approach. The best conditions were obtained with pure ACN, MgSO4/NaCl as extraction salts, MgSO4/PSA/C18 as clean-up, and the non-dilution of extracts. The impact of different HRMS acquisition modes on detection and identification rates were also evaluated. The screening detection limits were determined to be 0.01 mg.kg-1 and 0.1 for 66% and 87% of pesticides, respectively. These screening procedure was finally applied to different bivalve samples using target and suspect analysis. This allowed the identification of diuron and its metabolite 1-(3,4-dichlorophenyl)-3-methylurea in the investigated samples.


Assuntos
Bivalves , Praguicidas , Animais , Cromatografia Líquida de Alta Pressão , Praguicidas/análise , Espectrometria de Massas em Tandem
8.
Artigo em Inglês | MEDLINE | ID: mdl-34233575

RESUMO

The study aims to clarify the current controversy related to conflicting reports on whether presence of Cr(VI) in rice is possible or not. For this purpose, a method was employed for the single run speciation analysis of Cr(III) and Cr(VI) in rice samples using species-specific isotope dilution (SS-ID) and high performance liquid chromatography coupled to inductively coupled mass-spectrometry (HPLC-ICP-MS) and selective single run species complexation/derivatisation. The quantification limits (LOQs) were 0.014 µg kg-1 for Cr(III) and 0.047 µg kg-1 for Cr(VI), while the detection limits (LODs) were 0.004 and 0.014 µg kg-1 for Cr(III) and Cr(VI), respectively. A total of 10 rice samples of different origin and colour (depending on the type of industrial processing) were analysed in this study. The content of Cr(VI) was below the limit of quantification in all of the rice samples analysed, while the Cr(III) levels ranged between 0.59 (whole grain rice) up to 104 µg kg-1 (brown rice). All samples were also analysed for their total Cr (Crtotal) content by ICP-MS solely and the results were in all cases comparable with the Cr(III) levels determined in the same samples. To assess the stability of Cr(III) and Cr(VI) in rice, one sample was spiked with Cr(III) and Cr(VI) (individually) at different levels (5.0, 10, 15 and 20 µg kg-1), held for 2 h, and then analysed by SS-ID HPLC-ICP-MS. The results showed a complete reduction of Cr(VI) to Cr(III), while Cr(III) remained stable at all spiking levels. These findings support the general statement from the European Food Safety Authority related to the complete absence of Cr(VI) in foods and confirms that Cr in rice is found solely as Cr(III) species.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/química , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Alimentos , Oryza/química , Clorambucila/química , Limite de Detecção , Espectrometria de Massas , Prednisolona/química , Procarbazina/química , Vimblastina/química
9.
EFSA J ; 18(11): e06268, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33193868

RESUMO

The European Commission asked EFSA to update its previous Opinion on nickel in food and drinking water, taking into account new occurrence data, the updated benchmark dose (BMD) Guidance and newly available scientific information. More than 47,000 analytical results on the occurrence of nickel were used for calculating chronic and acute dietary exposure. An increased incidence of post-implantation loss in rats was identified as the critical effect for the risk characterisation of chronic oral exposure and a BMDL 10 of 1.3 mg Ni/kg body weight (bw) per day was selected as the reference point for the establishment of a tolerable daily intake (TDI) of 13 µg/kg bw. Eczematous flare-up reactions in the skin elicited in nickel-sensitised humans, a condition known as systemic contact dermatitis, was identified as the critical effect for the risk characterisation of acute oral exposure. A BMDL could not be derived, and therefore, the lowest-observed-adverse-effect-level of 4.3 µg Ni/kg bw was selected as the reference point. The margin of exposure (MOE) approach was applied and an MOE of 30 or higher was considered as being indicative of a low health concern. The mean lower bound (LB)/upper bound (UB) chronic dietary exposure was below or at the level of the TDI. The 95th percentile LB/UB chronic dietary exposure was below the TDI in adolescents and in all adult age groups, but generally exceeded the TDI in toddlers and in other children, as well as in infants in some surveys. This may raise a health concern in these young age groups. The MOE values for the mean UB acute dietary exposure and for the 95th percentile UB raises a health concern for nickel-sensitised individuals. The MOE values for an acute scenario regarding consumption of a glass of water on an empty stomach do not raise a health concern.

10.
Lancet Planet Health ; 4(7): e292-e300, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32681900

RESUMO

BACKGROUND: Human dietary exposure to chemicals can result in a wide range of adverse health effects. Some substances might cause non-communicable diseases, including cancer and coronary heart diseases, and could be nephrotoxic. Food is the main human exposure route for many chemicals. We aimed to assess human dietary exposure to a wide range of food chemicals. METHODS: We did a total diet study in Benin, Cameroon, Mali, and Nigeria. We assessed 4020 representative samples of foods, prepared as consumed, which covered more than 90% of the diet of 7291 households from eight study centres. By combining representative dietary surveys of countries with findings for concentrations of 872 chemicals in foods, we characterised human dietary exposure. FINDINGS: Exposure to lead could result in increases in adult blood pressure up to 2·0 mm Hg, whereas children might lose 8·8-13·3 IQ points (95th percentile in Kano, Nigeria). Morbidity factors caused by coexposure to aflatoxin B1 and hepatitis B virus, and sterigmatocystin and fumonisins, suggest several thousands of additional liver cancer cases per year, and a substantial contribution to the burden of chronic malnutrition in childhood. Exposure to 13 polycyclic aromatic hydrocarbons from consumption of smoked fish and edible oils exceeded levels associated with possible carcinogenicity and genotoxicity health concerns in all study centres. Exposure to aluminium, ochratoxin A, and citrinin indicated a public health concern about nephropathies. From 470 pesticides tested across the four countries, only high concentrations of chlorpyrifos in smoked fish (unauthorised practice identified in Mali) could pose a human health risk. INTERPRETATION: Risks characterised by this total diet study underscore specific priorities in terms of food safety management in sub-Saharan Africa. Similar investigations specifically targeting children are crucially needed. FUNDING: Standards and Trade Development Facility.


Assuntos
Dieta/estatística & dados numéricos , Exposição Dietética/efeitos adversos , Poluentes Ambientais/efeitos adversos , Análise de Alimentos , Análise de Perigos e Pontos Críticos de Controle , Benin , Camarões , Humanos , Mali , Nigéria
11.
Food Chem Toxicol ; 130: 308-316, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31102675

RESUMO

A total diet study (TDS) was conducted between 2010 and 2016 to assess the risk associated with chemicals in food of non-breast-fed children from 1 to 36 months living in France. Food samples were collected, prepared "as consumed", and analyzed for chemicals of public health interest. Acrylamide, furan and polycyclic aromatic hydrocarbons (PAHs) were analyzed as heat-induced compounds produced mainly during thermal processing of foods. Dietary exposure was assessed for 705 representative children using food consumptions recorded through a 3-consecutive-days record. As all calculated margins of exposure (MOE) for PAHs exceeded 10 000, dietary exposure of the infant and toddler population was deemed tolerable with regard to the carcinogenic risk. Conversely, the exposure levels to acrylamide and furan were considered as of concern, requiring management measures to reduce the exposure essentially by reducing the formation of heat-induced compounds during food production or preparation processes. Efforts should mainly focus on major contributors to the exposure, i.e. sweet and savoury biscuits and bars, and potatoes and potato products for acrylamide, baby jars of vegetables, with or without meat or fish for acrylamide and furan.


Assuntos
Acrilamida/química , Armazenamento de Alimentos , Furanos/química , Temperatura Alta , Alimentos Infantis/análise , Hidrocarbonetos Policíclicos Aromáticos/química , Acrilamida/toxicidade , Contaminação de Alimentos , França , Furanos/toxicidade , Humanos , Lactente , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Fatores de Risco
12.
Asian Pac J Cancer Prev ; 20(2): 355-367, 2019 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-30803193

RESUMO

Background: In French Polynesia, thyroid cancer mortality and incidence is reported to be the highest in the world. Excessive levels of non-essential trace elements (nETE) in the body are associated with several types of cancer. Objective: The present study aims to provide quantitative information on food contamination by mercury (Hg), lead (Pb), arsenic (As) and cadmium (Cd) in French Polynesia and its potential correlation with measurements performed in fingernails of Polynesians, and then to investigate the potential association between these nETE and different thyroid cancer risks. Methods: The study population included 229 interviewed cases and 373 interviewed controls We performed a descriptive analysis of Polynesian food and examined the association between thyroid cancer risk and daily intake levels of nETE and with fingernail nETE levels. Results: Hg contamination was mainly present in sea products, Pb contamination was present in almost all samples, Cd was detectable in starchy food and As was detectable in all sea products. No patient exceeded dietary contamination WHO limits for Pb, 2 participants exceeded it for Hg and 3 individuals (0.5%) for cadmium. In fingernail clippings, the most detectable pollutant was Pb (553 participants), then Hg (543 participants) then Cd (only in 130 participants). Thyroid cancer risk was increased more than 4 times by Pb daily intake in patients with a history of cancer in first-degree relatives than in ones without (p for interaction =0.01), and 2 times more in women with more than 3 pregnancies than in those with none or less (p for interaction =0.005); it was also increased following As intake by more than 30% in patients with a history of cancer in first-degree relatives than in ones without (p for interaction =0.05). Conclusion: Locally produced foods are not a source of nETE exposure in French Polynesia. Dieatry nETE exposure and fingernail nETE concentration are not associated to differentiated thyroid cancer risk. No correlation found between nETE dietary exposure and fingernail nETE concentration.


Assuntos
Exposição Dietética/efeitos adversos , Monitoramento Ambiental/métodos , Contaminação de Alimentos/análise , Unhas/metabolismo , Neoplasias da Glândula Tireoide/etiologia , Oligoelementos/efeitos adversos , Estudos de Casos e Controles , Exposição Dietética/análise , Suscetibilidade a Doenças , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Polinésia/epidemiologia , Prognóstico , Fatores de Risco , Neoplasias da Glândula Tireoide/epidemiologia , Oligoelementos/análise , Adulto Jovem
13.
Food Chem Toxicol ; 115: 358-364, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29580822

RESUMO

Besides specific occupational activities or smoking, food is the main route of cadmium exposure for the general population. In France a total diet study previously conducted for adults and children over 3 years old revealed that health concerns due to Cd dietary exposure existed for both adults and children. This study showed that the Cd tolerable weekly intake, based on potential nephrotoxicity effects, is exceeded by a high proportion of children under 3 years old. Nephrotoxicity results from the accumulation of cadmium in the kidney and appears typically after long-term exposure (40-50 years). Despite the exceeding of the tolerable weekly intake observed during the first three years of childhood, due to low body weights compared to adults, the accumulation rate of cadmium is much lower during the whole childhood period (from 0 to 17 years of age) than during adulthood. These data suggest that dietary exposure to cadmium should be reduced for both children and adults to prevent health concerns associated with nephrotoxicity in later life. Moreover, recent literature suggests that Cd can induce other adverse health effects (especially endocrine disruption or neurotoxicity) that could be triggered at even lower doses than those triggering nephrotoxicity.


Assuntos
Cádmio/toxicidade , Exposição Dietética , Alimentos Infantis/análise , Adolescente , Cádmio/análise , Criança , Pré-Escolar , Feminino , França , Humanos , Lactente , Recém-Nascido , Masculino , Medição de Risco
14.
Thyroid ; 26(12): 1752-1760, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27610545

RESUMO

BACKGROUND: The incidence of differentiated thyroid cancer (DTC) is low in Cuba, and the contribution of dietary factors to DTC in this population has not been investigated so far. The aim of this study was to evaluate the relationship between dietary iodine intake and DTC with regard to the interaction with environmental factors or some common single nucleotide polymorphisms (SNPs), based on a case-control study carried out in Cuba. METHODS: A total of 203 cases and 212 controls from the general population were interviewed face-to-face using the dietary intake questionnaire and the photo booklet from the E3N cohort. A specific food composition table was constructed for this study. For each parameter studied, the odds ratio (OR) was stratified on age group and sex, and further adjusted for dietary energy, smoking status, ethnic group, level of education, number of pregnancies, and body surface area. RESULTS: The risk of DTC was significantly reduced with increasing consumption of fish (p = 0.04), but no association between total dietary iodine intake and DTC risk was evident (p = 0.7). This lack of significant association was true whatever the age, the smoking status, the dietary selenium intake, and the ethnicity (p > 0.05). DTC risk was positively and strongly associated with the number of copies in the minor allele (A) for SNP rs965513 near FOXE1 among people who consumed less iodine than the median (p = 0.005). CONCLUSION: Overall, the majority of the studied population had an optimal dietary iodine intake. DTC risk was inversely associated with high fish consumption. Furthermore, DTC risk was positively associated with the number of copies in the minor allele (A) of rs965513 among people who consumed less iodine than the median. Because these findings are based on post-diagnostic measures, studies with pre-diagnostic dietary iodine are needed for confirmation.


Assuntos
Dieta , Fatores de Transcrição Forkhead/genética , Interação Gene-Ambiente , Iodo/administração & dosagem , Polimorfismo de Nucleotídeo Único , Neoplasias da Glândula Tireoide/etiologia , Adolescente , Adulto , Alelos , Estudos de Casos e Controles , Cuba , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Risco , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Adulto Jovem
15.
Food Chem ; 169: 134-40, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25236208

RESUMO

Pacific Island populations show some of the highest incidences of thyroid cancer in the world, and iodine deficiency is suspected to play a role. Iodine content was determined in 124 different French Polynesian food samples using inductively coupled plasma-mass spectrometry after alkaline digestion. For samples containing starch, the method was optimised by including an additional enzymatic treatment step. This analytical method was validated with an accuracy profile approach, using certified reference materials with iodine contents ranging from 0.027 to 4.95mgiodinekg(-1) dry weight. The trueness bias ranged from -5.8% to 22.4% and the highest observed intermediate precision coefficient of variation CVR was 11% in starchy materials. Tested Polynesian foods showed large variation in iodine content, with values of 0.014-0.032mgkg(-1) for fruits, 0.014-0.081mgkg(-1) for starchy samples, 0.027-1.85mgkg(-1) for green vegetables, 0.222-5.19mgkg(-1) for fish, 6.51-85.6mgkg(-1) for shellfish, and 0.004-1.39mgkg(-1) for beverages.


Assuntos
Bebidas/análise , Análise de Alimentos , Frutas/química , Iodo/análise , Alimentos Marinhos/análise , Verduras/química , Animais , Análise de Alimentos/métodos , Espectrometria de Massas/métodos , Polinésia
16.
Biometals ; 19(5): 473-81, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16937253

RESUMO

The influence of long-term exposure to cadmium (Cd) on essential minerals was investigated using a Caco-2 TC7 cells and a multi-analytical tool: microwave digestion and inductively coupled plasma mass spectrometry. Intracellular levels, effects on cadmium accumulation, distribution, and reference concentration ranges of the following elements were determined: Na, Mg, Ca, Cr, Fe, Mn, Co, Ni, Cu, Zn, Mo, and Cd. Results showed that Caco-2 TC7 cells incubated long-term with cadmium concentrations ranging from 0 to 10 micromol Cd/l for 5 weeks exhibited a significant increase in cadmium accumulation. Furthermore, this accumulation was more marked in cells exposed long-term to cadmium compared with controls, and that this exposure resulted in a significant accumulation of copper and zinc but not of the other elements measured. Interactions of Cd with three elements: zinc, copper, and manganese were particularly studied. Exposed to 30 micromol/l of the element, manganese showed the highest inhibition and copper the lowest on cadmium intracellular accumulation but Zn, Cu, and Mn behave differently in terms of their mutual competition with Cd. Indeed, increasing cadmium in the culture medium resulted in a gradual and significant increase in the accumulation of zinc. There was a significant decrease in manganese from 5 micromol Cd/l exposure, and no variation was observed with copper.


Assuntos
Cádmio/metabolismo , Cobre/metabolismo , Manganês/metabolismo , Espectrometria de Massas , Zinco/metabolismo , Células CACO-2 , Humanos , Micro-Ondas
17.
J AOAC Int ; 88(6): 1811-21, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16526466

RESUMO

A method validation of the total analysis of cadmium (Cd), lead (Pb), arsenic (As), and mercury (Hg) in foodstuffs by inductively coupled plasma/mass spectrometry (ICP/MS) after closed vessel microwave digestion is presented. Due to the lack of reference method for ICP/MS techniques in food and, based on the project of the European Committee of Normalization (CEN/TC 275/WG 10), the Agence Française de Normalisation (AFNOR) guidelines NF V03-110 were used for the evaluation of this method based on 2 steps, sample preparation and multielement detection. Several criteria considered as compulsory (linearity, specificity, precision under repeatability conditions, and trueness) have been estimated and discussed, in addition to intermediate precision reproducibility, the limit of detection, and the limit of quantification. Furthermore, a comparison with in-house methods using electrothermal atomic absorption was performed using an external proficiency testing scheme and food samples. The results indicated that this method could be used in the laboratory for the routine determination of these 4 cumulative toxic metals in foodstuffs with acceptable analytical performance.


Assuntos
Arsênio/análise , Cádmio/análise , Técnicas de Química Analítica/métodos , Chumbo/análise , Espectrometria de Massas/métodos , Mercúrio/análise , Oligoelementos/análise , Animais , Calibragem , Elementos Químicos , Alimentos , Análise de Alimentos , Contaminação de Alimentos , Micro-Ondas , Modelos Químicos , Modelos Estatísticos , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrofotometria , Espectrofotometria Atômica , Fatores de Tempo
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