RESUMO
This work describes a new method for the analysis of handwritten documents through a system composed of a pre-selector optical analyser equipped with light sources of different wavelengths coupled with bandpass filters combined with an optical coherence tomography (OCT) instrument. The optical analyser identifies regions with different pen pressures on the paper using specific wavelengths from ultraviolet (UV) to infrared (IR) and bandpass filters. Then the selected regions are analysed with a coherence tomography analyser to measure the depth of grooves and capture three-dimensional images. With this methodology, it is possible to identify similarities, or differences, between the pieces of evidence under investigation, increasing the possibility of correct attribution concerning the authorship of the signature and we also showed that this feature is independent of the paper substrate. In this work, a new strategy will be presented to categorize and quantify pen pressure in order to aid a better response for a forensic examiner. Thereby, from the observed areas that display higher pressures (more significant grooves), it is possible to determine the authorship of the signature.
RESUMO
BACKGROUND: The high amounts of phytic acid present in diets from developing countries are considered as important inhibitors of zinc (Zn) absorption. The present study aimed to assess the fractional absorption of Zn from a meal containing common Brazilian foods using the stable isotope technique. METHODS: Twelve men, aged 19-42 years, were fed a healthy experimental diet comprising lettuce, tomato, French fries, steak with onions, rice, beans, papaya, orange, pineapple, and passion fruit juice. Each subject received one intravenous dose of enriched (70) Zn, and the lunch was extrinsically labelled with enriched (67) Zn. Urinary (67) Zn and (70) Zn enrichments were assessed by inductively coupled plasma mass spectrometry. RESULTS: The labelled meal phytate : Zn molar ratio was very divergent with respect to chemically determined and calculated data. Subjects presented a normal Zn nutritional status before and after the study. The mean Zn absorption from the labelled meal was 30% (range 11-47%). CONCLUSIONS: According to the World Health Organization parameters, the results denote a moderate/high Zn bioavailability in the evaluated meal, with a variability in the absorption percentage that is similar to other studies. The data show that a typical Brazilian meal, with an adequate energy amount and a balanced macronutrient distribution, presents a Zn bioavailability in accordance with the worldwide recommended standard.
Assuntos
Ácido Fítico/administração & dosagem , Zinco/farmacocinética , Administração Intravenosa , Adulto , Disponibilidade Biológica , Brasil , Países em Desenvolvimento , Dieta , Relação Dose-Resposta a Droga , Alimentos Orgânicos , Humanos , Absorção Intestinal/efeitos dos fármacos , Masculino , Estado Nutricional , Ácido Fítico/efeitos adversos , Adulto Jovem , Zinco/sangue , Zinco/deficiênciaRESUMO
The West Indian manatee Trichechus manatus is threatened with extinction in Brazil, and this study focused on nondestructive blood samples analyzed for metals, polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), as well as biochemical and hematological biomarkers. Studied manatees were kept at Projeto Peixe-Boi headquarters in Pernambuco State, and at two natural areas in estuaries where they are released to the wild. Manatees kept at the natural estuary in Paraiba State have blood concentrations of Al, Pb, Cd, Sn that are 11, 7, 8 and 23 times greater, respectively, than the concentrations found in blood of animals from the same species in Florida, USA. An inhibition of butyrylcholinesterase in manatees kept at the two reintroduction sites in Alagoas and Paraiba States indicated possible exposure of the animals to cholinesterase inhibitor insecticides. PCBs and OCPs were not detected. Results from this study will help delineate conservation efforts in the region.
Assuntos
Monitoramento Ambiental , Trichechus manatus/sangue , Poluentes Químicos da Água/sangue , Animais , Biomarcadores/sangue , Brasil , Butirilcolinesterase/sangue , Metais/sangue , Bifenilos Policlorados/sangue , Poluição Química da Água/estatística & dados numéricosRESUMO
Over the last years, investigations on the increase of platinum (Pt), palladium (Pd), and rhodium (Rh) levels in urban environments of big cities all over the world - especially to catalytic converters emissions - have been grown up enormously. São Paulo City is the 6th largest megacity in the world having about 20 million inhabitants and an ever increasing seven million motor vehicle fleet. In spite of this, there has never been an investigation regarding Pt, Pd, and Rh levels in the city. In the present study, Pt, Pd, and Rh concentrations were determined in soils adjacent to seven main high-density traffic avenues in the metropolitan region of São Paulo City. Inductively coupled plasma mass spectrometry was employed - after ultrasound-assisted aqua regia leaching - as analytical technigue. The results showed concentration levels up to 378 ng g(-1) for Pd, 208 ng g(-1) for Pt, and 0.2 to 45 ng g(-1) for Rh. These levels are much higher than those considered for the geochemical background of soils, indicating a catalytic converter source. Due to the different Pt/Pd/Rh ratio in Brazilian automobile catalytic converters, lower levels of Pt/Pd ratios compared with other similar studies were observed. The obtained results are the first data for monitoring Pt, Pd, and Rh pollution in São Paulo City soils.
Assuntos
Monitoramento Ambiental , Paládio/análise , Platina/análise , Ródio/análise , Poluentes do Solo/análise , Brasil , Cidades , Humanos , Veículos Automotores , Solo/químicaRESUMO
We investigated chronic incorporation of metals in individuals from poor families, living in a small, restrict and allegedly contaminated area in São Paulo city, the surroundings of the Guarapiranga dam, responsible for water supply to 25% of the city population. A total of 59 teeth from individuals 7 to 60 years old were collected. The average concentrations of Pb, Cd, Fe, Zn, Mn, Ni and Cr were determined with an Atomic Absorption Spectrophotometer. The concentrations of all metals as function of the individuals' age exhibited a remarkable similarity: peaks between 7 and 10 years and sharply decreasing at higher ages, which could be attributed to alimentary habits and persistence to metals exposure all along the individuals' life span. From all the measured metals, lead and cadmium were a matter of much more concern since their measured values are close to the upper limits of the world wide averages.
Assuntos
Saúde Ambiental/métodos , Poluentes Ambientais/metabolismo , Poluição Ambiental/análise , Metais/metabolismo , Dente/química , Adolescente , Adulto , Brasil , Criança , Humanos , Pessoa de Meia-Idade , Espectrofotometria Atômica , Adulto JovemRESUMO
The south region of Sao Paulo city hosts the Guarapiranga dam, responsible for water supply to 25% of the city population. Their surroundings have been subject to intense and irregular occupation by people from very low socioeconomics classes. Measurements undertaken on sediment and particulate materials in the dam revealed concentrations of lead, copper, zinc and cadmium above internationally accepted limits. Epidemiological and toxicological studies undertaken by the World Health Organization in individuals exhibiting lead concentrations in blood, near or below the maximum recommended (10 microg dl(-1)), surprisingly revealed that toxic effects are more intense in individuals belonging to low socioeconomics classes. Motivated by these facts, we aimed at the investigation of chronic incorporation of lead, as well as the use of our BIOKINETICS code, which is based on an accepted ICRP biokinetics model for lead, in order to extrapolate the results from teeth to other organs. The focus of our data taking was children from poor families, living in a small, restrict and allegedly contaminated area in São Paulo city. Thus, a total of 74 human teeth were collected. The average concentration of lead in teeth of children 5 to 10 years old was determined by means of a high-resolution inductively coupled plasma mass spectrometer (ICP-MS). For standardization of the measurements, an animal bone certified material (H-Animal Bone), from the International Atomic Energy Agency, was analyzed. The amount of lead in children living in the surroundings of the dam, was approximately 40% higher than those from the control region, and the average lead concentration was equal to 1.3 microg g(-1) approximately. Grouping the results in terms of gender, tooth type and condition, it was concluded that a carious molar of boys is a much more efficient contamination pathway for lead, resulting in concentrations 70% higher than in the control region. We also inferred the average concentrations of lead in other organs of these children, by making use of our BIOKINETIC code.
Assuntos
Exposição Ambiental , Chumbo/análise , Chumbo/toxicidade , Dente/química , Adolescente , Disponibilidade Biológica , Brasil , Criança , Pré-Escolar , Simulação por Computador , Fator F , Feminino , Humanos , Masculino , Espectrometria de Massas/métodos , Espectrometria de Massas/normasRESUMO
The Southwest region of the Bahia state in Brazil hosts the largest uranium reserve of the country (100 kton in uranium, only), plus the cities of Caetité, Lagoa Real and Igaporã. In this work, aim was at the investigation of uranium burdens on residents of these cities by using teeth as bioindicators, as a contribution for possible radiation protection measures. Thus, a total of 41 human teeth were collected, plus 50 from an allegedly uranium free area (the control region). Concentrations of uranium in teeth from residents of 5- to 87-y old were determined by means of a high-resolution inductively coupled plasma mass spectrometer (ICP-MS). The highest uranium concentration in teeth was measured from samples belonging to residents of Caetité (median equal to 16 ppb). Assuming that the uranium concentrations in teeth and bones are similar within 10-20% (for children and young adults), it concluded that uranium body levels in residents of Caetité are at least one order of magnitude higher than the worldwide average. This finding led to conclude that daily ingestion of uranium, from food and water, is equally high.
Assuntos
Monitoramento Ambiental/métodos , Contaminação Radioativa de Alimentos/análise , Dente/química , Urânio/análise , Urânio/farmacocinética , Poluentes Radioativos da Água/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Humanos , Masculino , Pessoa de Meia-Idade , Modelos BiológicosRESUMO
The aim of the present study was to evaluate mercury and selenium concentrations in hair samples of reproductive age women from riverside communities of the Tapajós River basin. We studied 19 pregnant and 21 non-pregnant women, 13 to 45 years old, living in the region for at least 2 years, and having a diet rich in fish. The analysis of Se and total Hg were performed in the Instituto de Pesquisas Energéticas e Nucleares (IPEN, São Paulo, Brazil) by using a Varian AA220-FS atomic absorption spectrometer with a flow injection system. There were no differences between the two groups - pregnant and non-pregnant -- concerning age (23.80 +/- 6.92 and 26.60 +/- 9.60 years old, respectively) and residential time (20.21 +/- 8.30 and 22.20 +/- 10.90 years, respectively). The geometric means and ranges for total Hg concentration were similar (p > 0.05): 8.25 microg/g (1.51-19.43) in pregnant and 9.39 microg/g (5.25-21.00) in non-pregnant women, respectively. Total Hg concentrations were also similar in different gestational stages. However, there was a significant difference between the two groups (p < 0.05, Student t test) in relation to Se concentration: 0.61 microg/g (0.40-2.33) in pregnant and 2.46 microg/g (0.92-5.74) in non-pregnant women, respectively. We concluded that Hg exposure levels in reproductive age women were only slightly higher than a provisional tolerable weekly intake of MeHg would provide, that Hg concentration in maternal hair samples was independent of gestational age, and that low Se concentration in pregnant women indicates high mineral consumption by fetal organism to satisfy their metabolic requirements raised during pregnancy, including as a protective mechanism for Hg cytotoxic effects.
Assuntos
Poluentes Ambientais/análise , Contaminação de Alimentos , Cabelo/química , Mercúrio/análise , Selênio/análise , Adolescente , Adulto , Animais , Brasil , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Feminino , Peixes , Humanos , Mercúrio/metabolismo , Pessoa de Meia-Idade , Gravidez , Rios , Selênio/metabolismoRESUMO
The distribution of platinum, palladium, and rhodium in soils adjacent to a major road in São Paulo, Brazil, is presented. Sampling was made at four sites with varying traffic volumes and driving styles (stop/start vs. constant speed). High-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) with NiS fire assay collection and Te coprecipitation was used as analytical procedure. The platinum group element (PGE) pattern distribution in the analyzed roadside soil was similar to that of other traffic-related elements such as Zn and Cu, characterized by a strong decrease of the PGE content with increasing distance from the traffic lane. The results indicate that the PGE concentrations in roadside soil are directly influenced by traffic conditions and distance, which characterize their catalytic converter origin. Pt, Pd, and Rh contents range between 0.3 and 17 ng g(-1), 1.1 and 58 ng g(-1), and 0.07 and 8.2 ng g(-1) respectively. Lower levels of Pt and lower Pt/Pd ratios in relation to similar studies in other countries were observed due to the different Pt/Pd ratios in Brazilian automobile catalytic converters. This is the first study to assess traffic-derived Pt, Pd, and Rh deposition in Brazil.
Assuntos
Monitoramento Ambiental , Veículos Automotores , Paládio/análise , Platina/análise , Ródio/análise , Poluentes do Solo/análise , Brasil , Veículos Automotores/normasRESUMO
The effects of maternal exposure to lead (Pb) during the perinatal (1% and 0.1% Pb) periods of sexual brain differentiation were studied in adult male offspring. Maternal Pb levels were measured after treatment. Behavioral (open field and sexual behavior), physical (sexual maturation, body and organ weights), and biochemical (testosterone levels and hypothalamic monoamine and respective metabolite levels) data were assessed in perinatally exposed offspring. The effects of gonadrotopin-releasing hormone (GnRH) administration to pups at birth on puberty and sexual behavior were also investigated in offspring postnatally exposed to the metal. Results showed that perinatal administration of the two Pb concentrations did not modify maternal weight gain; 1% Pb exposure reduced offspring body weight during the 7 days of treatment while no changes were observed after 0.1% Pb exposure; neither Pb concentration altered offspring sexual maturation; the higher Pb concentration improved sexual behavior while the 0.1% concentration reduced it; exposure to 0.1% Pb caused decrease in testis weight, an increase in seminal vesicle weight and no changes in plasma testosterone levels; hypothalamic VMA levels were increased compared to the control group; GnRH administration reversed the effects of 0.1% Pb administration on male sexual behavior. These results show that perinatal exposure to Pb had a dose-dependent effect on the sexual behavior of rats and that a decrease in GnRH source in the offspring was probably involved in the reduction of their sexual performance.
Assuntos
Animais Recém-Nascidos/fisiologia , Hormônio Liberador de Gonadotropina/farmacologia , Chumbo/toxicidade , Comportamento Sexual/efeitos dos fármacos , Animais , Monoaminas Biogênicas/metabolismo , Peso Corporal/efeitos dos fármacos , Feminino , Genitália Feminina/efeitos dos fármacos , Genitália Feminina/crescimento & desenvolvimento , Genitália Masculina/efeitos dos fármacos , Genitália Masculina/crescimento & desenvolvimento , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Chumbo/sangue , Masculino , Tamanho do Órgão/efeitos dos fármacos , Gravidez , Ratos , Ratos Wistar , Maturidade Sexual/efeitos dos fármacos , Testosterona/sangueRESUMO
The environmental exposure to mercury by riverine and Indian communities can occur through the ingestion of fish and products contaminated by mercury compounds. The present study aims to evaluate the total mercury concentration in the different fish species most consumed in the municipality of Itaituba, Tapajós river basin, where there are intense gold-mining activities. These fish samples were analyzed by atomic absorption spectrophotometry by cold vapor technique, Automatic Mercury Analyzer HG-3500. The largest mercury concentrations were found in the carnivorous species ranging from 112.4 to 2250 microg/g, while the detritivorous, herbivorous and omnivorous species presented total mercury levels ranging from 3.2 to 309.8 microg/g, which is below the limit established by the World Health Organization. This paper also reports and identifies which species are more polluted and present a statistical relationship among concentration and weight of the carnivorous species studied in detail, Brachyplatystoma flavicans (dourada) (r2 = 0.691) and Pseudoplatystoma sp. (surubim) (r2 = 0.654).
Assuntos
Peixes , Mercúrio/análise , Saúde Pública , Poluentes Químicos da Água/análise , Animais , Constituição Corporal , Brasil , Dieta , Monitoramento Ambiental , Humanos , Mercúrio/efeitos adversos , Poluentes Químicos da Água/efeitos adversosRESUMO
Gold extraction and its commercialization in the Amazon region is mainly by rudimentary procedures. Therefore, during the process of extraction and recovery of this precious metal, large amounts of mercury vapors are thrown into the environment. This paper is an attempt to establish a correlation between the concentration of total mercury in the urine of workers at the gold shop in the Municipality of Itaituba, Pará, and the information related to the lifestyles of each individual studied. Through statistical analysis, it was possible to divide the workers into three groups: people with normal mercury concentrations, [Hg] < or = 10 ppb, (29%); with concentrations at the biological limit of tolerance, [Hg] up to 50 ppb, (49%); and contaminated people, [Hg] > or = 50 ppb (22%). It may be concluded that fish consumption, time of alcohol consumption, number of amalgam fillings, as well as working hours, are important variables when evaluating mercurial contamination of people who are occupationally exposed to mercury vapors.
Assuntos
Mercúrio/urina , Exposição Ocupacional/análise , Adulto , Ouro , Humanos , Exposição por Inalação , Masculino , Pessoa de Meia-Idade , VolatilizaçãoRESUMO
This paper reports on total mercury concentrations in edible tissue from 11 fish species caught in the Municipality of Santarém, Tapajós River Basin, Pará State, which are most consumed by the local population and investigates the influence of the distance between the goldmining areas and Santarém city on fish contamination by mercury. It was found that the carnivorous species reached an average of 222.1 ng.g(-1) (n=69), higher than the herbivorous species with 31.9 ng.g(-1) (n=30) and the omnivorous species with 68.7 ng.g(-1) (n=10). Significant relationships are found between fish weight and total mercury concentrations by using descriptive statistical and regression analysis for the two species, the carnivorous Pellona sp. (Sarda, r=0.73) and Pseudoplatystoma sp. (Surubim, r=0.63).
Assuntos
Peixes , Mercúrio/análise , Animais , Peso Corporal , Brasil , Monitoramento Ambiental , Contaminação de Alimentos , Ouro , Humanos , Mineração , Saúde Pública , Alimentos Marinhos , Distribuição TecidualRESUMO
The capability of pine needles to be used as bioindicators of trace metals in the environment is discussed. Samples were collected around the Instituto de Pesquisas Energéticas e Nucleares, the largest nuclear research center in South America and chosen to be the sampling target area. Results obtained for the elemental content of Th and U in samples collected nearby an uranium facility were, respectively, 0.072 and 0.042 mg kg(-1), while the results obtained for the La, Ce and Sm content in a sample collected in the vicinity of an extraction laboratory were, respectively, 0.22, 0.88 and 0.39 mg kg(-1). All these values are higher than the ones obtained with a reference sample (La 0.12; Ce 0.19, Th 0.020 and U 0.012 mg kg(-1)), located far from the target area. Internal standardization was used to compensate the non-spectral interference of the different elements present in the sample solution matrix. The chemical elements bismuth (Bi) and indium (In) were chosen as internal standards. In order to control the accuracy of the chemical measurement process, certified samples of pine needles (NBS SRM 1575) were also analyzed. The results obtained show the capability of the investigated method in the determination of the relevant trace metals in the environment.