RESUMO
The global burden of water-based lead (Pb) exposure on children is largely unknown; however, the importance of water sources as a path of Pb exposure is receiving increased attention due to recent prominent exposure events related to corroded plumbing infrastructure in the US. This study investigated the contribution of Pb in household drinking and cooking water to Pb levels in blood (PbB) and urine (PbU) within 353 early school-aged children from Montevideo, Uruguay. Additionally, the analysis considered the child's iron status and the water content of iron (WFe) and zinc (WZn) in relation to water Pb and blood/urine Pb concentrations. Lead concentrations for both PbB and PbU were fairly low (M⯱â¯SD: 4.2⯱â¯2.1⯵g/dL; Median [5%, 95%]: 1.9 [0.6, 5.1⯵g/L, respectively]); however 21% of the sample had a PbB >5⯵g/dL butâ¯≤â¯10⯵g/dL. Overall, there was little evidence of an association between water metal concentrations and children's PbB/PbU. However, when the sample was stratified by children's iron status, WPb was positively related to PbU, but negatively related to PbB in iron-replete children, even after adjusting for WFe and WZn. In iron-deficient children, there was no elevation in PbU with increasing WPb. In this sample of children with low Pb levels, there were no overwhelming relationships between WPb and either PbB or PbU, however, there was some evidence that iron-replete status promotes excretion of WPb.
Assuntos
Água Potável/química , Exposição Ambiental/análise , Ferro/química , Chumbo/sangue , Chumbo/química , Chumbo/urina , Zinco/química , Criança , Água Potável/análise , Feminino , Humanos , Ferro/análise , Chumbo/análise , Masculino , Uruguai , Zinco/análiseRESUMO
Vulnerability assessments are commonly based on complex indices that may be inappropriate for characterizing risks in small groups of people exposed to environmental hazards. The aim was to present a multivariate and geostatistical approach to explore human health risks at the individual, household and community level. First, biological and socioeconomic characteristics from 179 children were used in a cluster analysis to find groups and identify vulnerability profiles. Then, both the exposure of children to arsenic and lead in soils and their accessibility to community resources were assessed using a geospatial analysis. The results identified three vulnerability profiles among children that were not in agreement with the environmental exposure and deficit of community resources. The proposed approach helps optimize strategies to manage both environmental and social risks based on the vulnerability of the exposed population.
Assuntos
Exposição Ambiental/análise , Medição de Risco/métodos , Fatores Socioeconômicos , Populações Vulneráveis/estatística & dados numéricos , Adolescente , Arsênio/análise , Arsênio/urina , Criança , Chile , Análise por Conglomerados , Humanos , Chumbo/análise , Chumbo/urina , Poluentes do Solo/análise , Poluentes do Solo/urina , Análise EspacialRESUMO
Lead exposure remains an important public health problem. Contaminated foods may act as a source of lead exposure, while certain nutrients may reduce lead absorption. We examined the cross-sectional associations of dietary patterns and the intake of several nutrients and foods with blood (Pb-B) and urinary (Pb-U) lead concentrations in children (5-8y) from Montevideo, Uruguay. From two 24-hour recalls completed by caregivers, we derived the mean daily intake of select nutrients and food groups (dairy, milk, fruit, root vegetables, foods rich in heme and non-heme iron), as well as "nutrient dense" and "processed" food patterns. Pb-B (n=315) was measured using atomic absorption spectrometry; Pb-U (n=321) using ICP-MS. Pb-U was adjusted for specific gravity and log-transformed to approximate a normal distribution. Iron deficiency (ID) and dietary variables were tested as predictors of Pb-B and log-Pb-U in covariate-adjusted regressions. Median [5%, 95%] Pb-B and Pb-U were 3.8 [0.8-7.8] µg/dL and 1.9 [0.6-5.1] µg/L, respectively; ~25% of Pb-B above current U.S. CDC reference concentration of 5µg/dL. ID was associated with 0.75µg/dL higher Pb-B, compared to non-ID (p<0.05). Consumption of root vegetables was not associated with Pb-B or log-Pb-U. Higher scores on the nutrient-dense pattern were related with higher Pb-Bs, possibly due to consumption of green leafy vegetables. Dietary intake of iron or iron-rich foods was not associated with biomarkers of lead. Conversely, children consuming more calcium, dairy, milk and yogurt had lower Pb-B and log-Pb-U. Our findings appear consistent with existing recommendations on including calcium-rich, but not iron- or vitamin-C-rich foods in the diets of lead-exposed children, especially where the consumption of these foods is low.
Assuntos
Dieta , Poluentes Ambientais/sangue , Poluentes Ambientais/urina , Chumbo/sangue , Chumbo/urina , Estado Nutricional , Criança , Cidades , Laticínios , Monitoramento Ambiental , Feminino , Frutas , Humanos , Deficiências de Ferro , Masculino , Uruguai , VerdurasRESUMO
Environmental hazards from natural or anthropological sources are widespread, especially in the north-central region of Mexico. Children represent a susceptible population due to their unique routes of exposure and special vulnerabilities. In this study we evaluated the association of exposure to environmental kidney toxicants with kidney injury biomarkers in children living in San Luis Potosi (SLP), Mexico. A cross-sectional study was conducted with 83 children (5-12 years of age) residents of Villa de Reyes, SLP. Exposure to arsenic, cadmium, chromium, fluoride and lead was assessed in urine, blood and drinking water samples. Almost all tap and well water samples had levels of arsenic (81.5%) and fluoride (100%) above the permissible levels recommended by the World Health Organization. Mean urine arsenic (45.6ppb) and chromium (61.7ppb) were higher than the biological exposure index, a reference value in occupational settings. Using multivariate adjusted models, we found a dose-dependent association between kidney injury molecule-1 (KIM-1) across chromium exposure tertiles [(T1: reference, T2: 467pg/mL; T3: 615pg/mL) (p-trend=0.001)]. Chromium upper tertile was also associated with higher urinary miR-200c (500 copies/µl) and miR-423 (189 copies/µL). Arsenic upper tertile was also associated with higher urinary KIM-1 (372pg/mL). Other kidney injury/functional biomarkers such as serum creatinine, glomerular filtration rate, albuminuria, neutrophil gelatinase-associated lipocalin and miR-21 did not show any association with arsenic, chromium or any of the other toxicants evaluated. We conclude that KIM-1 might serve as a sensitive biomarker to screen children for kidney damage induced by environmental toxic agents.
Assuntos
Arsênio/urina , Cromo/urina , Poluentes Ambientais/urina , Receptor Celular 1 do Vírus da Hepatite A/metabolismo , Arsênio/análise , Arsênio/sangue , Biomarcadores/urina , Criança , Pré-Escolar , Cromo/análise , Cromo/sangue , Creatinina/sangue , Água Potável/análise , Exposição Ambiental , Poluentes Ambientais/análise , Poluentes Ambientais/sangue , Feminino , Fluoretos/análise , Fluoretos/sangue , Fluoretos/urina , Taxa de Filtração Glomerular , Água Subterrânea/análise , Humanos , Nefropatias/sangue , Nefropatias/urina , Chumbo/análise , Chumbo/sangue , Chumbo/urina , Lipocalina-2/urina , Masculino , México , MicroRNAs/urina , Albumina Sérica/análiseRESUMO
BACKGROUND: Attention deficit hyperactivity disorder is the most common neuropsychiatric disorder in children; symptoms can persist into adult life by 60 %. Our objective was to quantify the levels of lead in blood and urine in pediatric patients with attention deficit hyperactivity disorder. METHODS: We did an observational study which included a captive population of children diagnosed with attention deficit hyperactivity disorder in the mental health service of Hospital General, from Centro Médico Nacional La Raza. Lead levels were determined in blood and urine by atomic absorption technique. RESULTS: We included 39 patients, 932 % male, with a mean age of 9.2 ± 2.16 years. The deficit and hyperactivity disorder combined type was the most frequent (69.2 %); 49 % of patients were found with toxic lead levels in blood (above 10 mg/dL); 17.9 % with stage III and 5.12 % with stage IV, according to the Mexican Official Standard (NOM-199-SSA-2000). Significant association was found between blood lead levels and the clinical expression of attention deficit hyperactivity disorder. CONCLUSIONS: Levels of lead exposure during early childhood have been shown to be inversely proportional to neurological development in the first seven years of life. Data results are insufficient to relate them with causality.
INTRODUCCIÓN: los síntomas del trastorno por déficit de atención e hiperactividad pueden persistir hasta la vida adulta en 60 % de quienes la padecieron en la niñez. Nuestro objetivo fue cuantificar los niveles de plomo en la sangre y la orina en niños con diagnóstico de trastorno por déficit de atención e hiperactividad para identificar si existe alguna relación. MÉTODOS: estudio observacional que incluyó a una muestra cautiva del Servicio de Higiene Mental del Hospital General del Centro Médico Nacional La Raza, con diagnóstico de trastorno por déficit de atención e hiperactividad. Se cuantificaron los niveles séricos y urinarios del plomo mediante la técnica de absorción atómica. RESULTADOS: se incluyeron 39 pacientes, 92.3 % del sexo masculino, con una edad promedio de 9.2 ± 2.16 años. El trastorno por déficit de atención e hiperactividad combinado fue el más frecuente (69.2 %). En 49 % de los pacientes se encontraron niveles de plomo en sangre superiores a 10 ?g/dL. Conforme los parámetros establecidos en la NOM-199-SSA1-2000, 17.9 % clasificaba en estadio III y 5.12 % en estadio IV. Se encontró relación significativa entre los niveles de plomo y la expresión clínica del trastorno por déficit de atención e hiperactividad. CONCLUSIONES: los niveles de exposición al plomo durante la infancia temprana han demostrado ser inversamente proporcionales al desarrollo neurológico en los primeros siete años de vida. Los datos son insuficientes para inferir la causalidad.
Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/etiologia , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/efeitos adversos , Chumbo/efeitos adversos , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/sangue , Transtorno do Deficit de Atenção com Hiperatividade/urina , Biomarcadores/sangue , Biomarcadores/urina , Criança , Pré-Escolar , Exposição Ambiental/análise , Poluentes Ambientais/sangue , Poluentes Ambientais/urina , Feminino , Humanos , Chumbo/sangue , Chumbo/urina , Masculino , México , Fatores de RiscoRESUMO
A novel ion imprinted polyvinylimidazole-silica hybrid copolymer (IIHC) was synthesized and used as a selective solid sorbent for Pb(2+) ions preconcentration using an on-line solid phase extraction (SPE) system coupled to TS-FF-AAS. The ionic hybrid sorbent was prepared using 1-vinylimidazole and 3-(trimethoxysilyl)propylmethacrylate as monomers, Pb(2+) ions as template, tetraethoxysilane as reticulating agent and 2,2'-azobis-isobutyronitrile as initiator. The best on-line SPE conditions concerning sorption behavior, including sample pH (6.46), buffer concentration (9.0 mmol L(-1)), eluent (HNO(3)) concentration (0.5 mol L(-1)) and preconcentration flow rate (4.0 mL min(-1)), were optimized by means of full factorial design and Doehlert matrix. The analytical curve ranged from 2.5 to 65.0 µg L(-1) (r=0.999) with limit of detection of 0.75 µg L(-1); the precision (repeatability) calculated as relative standard deviation (n=10) was 5.0 and 3.6% for Pb(2+) concentration of 10.0 and 60.0 µg L(-1), respectively. From on-line breakthrough curve, column capacity was 3.5 mg g(-1). Preconcentration factor (PF), consumptive index (CI) and concentration efficiency (CE) were 128.0, 0.16 mL and 25.6 min(-1), respectively. The selective performance of the sorbent, based on relative selectivity coefficient, was compared to NIC (non imprinted copolymer) for the binary mixture Pb(2+)/Cd(2+), Pb(2+)/Cu(2+) and Pb(2+)/Zn(2+). The results showed that ion imprinted polyvinylimidazole-silica hybrid polymer had higher selectivity for Pb(2+) than NIC at 64.9, 16.0 and 8.8 folds. The developed method was successfully applied for highly sensitive and selective Pb(2+) determination in different kinds of water samples, parenteral solutions and urine. Accuracy was also assessed by analyzing certified reference fish protein (DORM-3) and marine sediment (MESS-3 and PACS-2) with satisfactory results.
Assuntos
Poluentes Ambientais/análise , Imidazóis/química , Chumbo/análise , Impressão Molecular/métodos , Polímeros/síntese química , Polivinil/química , Dióxido de Silício/química , Espectrofotometria Atômica , Poluentes Ambientais/isolamento & purificação , Poluentes Ambientais/urina , Análise de Injeção de Fluxo , Concentração de Íons de Hidrogênio , Íons/química , Chumbo/isolamento & purificação , Chumbo/urina , Polímeros/química , Extração em Fase SólidaRESUMO
Paints are composed of an extensive variety of hazardous substances, such as organic solvents and heavy metals. Biomonitoring is an essential tool for assessing the risk to occupational health. Thus, this study analyzed the levels of biomarkers of exposure for toluene, xylene, styrene, ethylbenzene, and lead, as well as the oxidative stress biomarker alterations in painters of an industry. Lipid peroxidation biomarker (MDA), delta-aminolevulinate dehydratase (ALA-D), nonprotein thyol groups, superoxide dismutase and catalase (CAT) were analyzed in exposed and nonexposed subjects. We estimated which of the paint constituents have the greatest influence on the changes in the biomarkers of oxidative stress in this case of co-exposure. The results demonstrated that despite the fact that all the biomarkers of exposure were below the biological exposure limits, the MDA levels and antioxidant enzyme activities were increased, while nonprotein thyol groups and ALA-D levels were decreased in painters when compared with nonexposed subjects. After statistic test, toluene could be suggested as the principal factor responsible for increased lipid peroxidation and inhibition of ALA-D enzyme; however, further studies on the inhibition of ALA-D enzyme by toluene are necessary.
Assuntos
Exposição Ocupacional/análise , Estresse Oxidativo/efeitos dos fármacos , Pintura/toxicidade , Xenobióticos/toxicidade , Adulto , Poluentes Ocupacionais do Ar/toxicidade , Poluentes Ocupacionais do Ar/urina , Derivados de Benzeno/toxicidade , Derivados de Benzeno/urina , Biomarcadores/sangue , Biomarcadores/urina , Catalase/sangue , Creatina/urina , Humanos , Chumbo/toxicidade , Chumbo/urina , Peroxidação de Lipídeos/efeitos dos fármacos , Saúde Ocupacional , Sintase do Porfobilinogênio/sangue , Medição de Risco , Estireno/toxicidade , Estireno/urina , Superóxido Dismutase/sangue , Tolueno/toxicidade , Tolueno/urina , Xenobióticos/urina , Xilenos/toxicidade , Xilenos/urinaRESUMO
The analysis of human biological samples, such as blood, urine, nails, and hair, is generally used for the verification of human exposure to toxic metals. In this review, various spectrometric methods for the determination of cadmium and lead in biological samples are discussed and compared. Several spectrometric techniques are presented and discussed with respect to various characteristics such as sensitivity, selectivity, and cost. Special attention is drawn to the procedures for digestion prior to the determination of cadmium and lead in hair, nails, blood, and urine.
Assuntos
Cádmio , Cabelo/química , Chumbo , Unhas/química , Espectrofotometria Atômica/métodos , Cádmio/sangue , Cádmio/química , Cádmio/urina , Humanos , Chumbo/sangue , Chumbo/química , Chumbo/urinaRESUMO
O objetivo deste estudo foi a avaliação da exposição ocupacional ao chumbo e manganês dos trabalhadores de uma oficina de recuperação de armamento de uma organização militar. O ar do ambiente de trabalho foi avaliado no monitoramento ambiental e os indicadores biológicos de dose interna, para chumbo e manganês, em sangue e na urina, foram utilizados no monitoramento biológico. A concentração de manganês e chumbo nos filtros e fluidos biológicos foi determinada por espectrometria de absorção atômica eletrotérmica. Os resultados do monitoramento ambiental indicaram níveis de Pb e Mn acima do TLV-TWA durante o processo de pintura (313,33 μg m-3) e solda (951 μg m-3). Os indicadores biológicos revelaram que cinco dos nove trabalhadores apresentam níveis de Pb-S que sugerem exposição ambiental ao chumbo (valores entre 5 e 10 μg dL-1). Pode-se concluir que existe uma pequena exposição ocupacional ao chumbo e ao manganês na oficina de tratamento superficial. Tal exposição é influenciada pelas condições meteorológicas e pela demanda variável de trabalho.
The aim of this study was the occupational exposure assessment to lead and manganese of workers in an armament repair shop of a military organization. The air of the working environment was assessed in the environmental monitoring while the internal dose biological indicators for lead and manganese, in blood and urine, were used in biological monitoring. Metals concentration in filters and biological fluids were determined by electrothermal atomic absorption spectrometry. The results of the environmental monitoring showed lead and manganese levels above the TLV-TWA during the process of painting (313.33 g m-3) and solder (951 μg m-3). The biological indicators revealed that five of the nine employees presented Pb-S levels that suggested an environmental exposure to lead (values between 5 and 10 μg dL-1). It can be concluded that there is a small occupational exposure to lead and manganese in the superficial treatment repair shop. This exposure is influenced by weather conditions and the variable demand of work.
Assuntos
Feminino , Humanos , Masculino , Chumbo/sangue , Chumbo/urina , Manganês/sangue , Manganês/urina , Exposição Ocupacional/análise , ArmasRESUMO
Lead exposure is an important issue in the research of several toxic effects resulting from the biochemical interaction between this metal and the organism. Calcium is a fundamental mineral for the maintenance of the organism homeostasis where there is interaction between lead and calcium in metabolic pathways. Environmental lead exposure by verifying the usefulness and applicability of urinary calcium/creatinine ratio (UCa/Cr) in this context was evaluated. This was an extensive socio-demographic study of the nutritional profile, lead exposure biomarkers in blood and the urine and UCa/Cr ratio. The children studied were from a low socio-economic group characterized by unsatisfactory nutritional diet. Lead environmental exposure was shown by biomarkers, with UCa/Cr ratio having positive and significant correlations with both lead and delta-aminolevulinic acid in urine (ALA-U), without colinearity diagnosis. There was a strong association between calcium excretion and lead exposure as a result of linear regression construction models. In children, lead increases calcium excretion which is an additional risk to infantile health. Urinary calcium/creatinine ratio may be a useful tool in the biological monitoring of lead exposure and health promotion programs.