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1.
Environ Res ; 205: 112545, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-34896087

RESUMEN

Emerging evidence shows that the gut microbiota interacts with environmental pollutants, but the effect of early exposure on the neonatal microbiome remains unknown. We investigated the association between maternal exposure to environmental pollutants and changes in early-life gut microbiome development. We surveyed 16S rRNA gene on meconium and fecal samples (at 1, 3, and 6 months) from the Brazilian birth cohort, and associated with levels of metals, perfluoroalkyl chemicals (PFAS), and pesticides in maternal and umbilical cord blood. The results indicate that the magnitude of the microbiome changes associated with increasing pollutant exposure was bigger in cesarean-section (CS) born and CS-born-preterm babies, in relation to vaginally (VG) delivered infants. Breastfeeding was associated with a stronger pollutant-associated effect on the infant feces, suggesting that the exposure source could be maternal milk. Differences in microbiome effects associated with maternal or cord blood pollutant concentrations suggest that fetal exposure time - intrauterine or perinatal - may matter. Finally, despite the high developmental microbiota variability, specific microbionts were consistently affected across all pollutants, with taxa clusters found in samples from infants exposed to the highest toxicant exposure. The results evidence that perinatal exposure to environmental pollutants is associated with alterations in gut microbiome development which may have health significance.


Asunto(s)
Contaminantes Ambientales , Microbioma Gastrointestinal , Cohorte de Nacimiento , Estudios de Cohortes , Contaminantes Ambientales/toxicidad , Heces , Femenino , Humanos , Lactante , Recién Nacido , Embarazo , ARN Ribosómico 16S/genética
2.
Contact Dermatitis ; 83(2): 88-93, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32212167

RESUMEN

BACKGROUND: Nickel is a ubiquitous element used in many everyday items. In recent decades nickel has become a leading allergen, which has become a public health problem. OBJECTIVE: To evaluate frequently used nickel products in Brazil. We investigated if these objects release nickel that is capable of inducing sensitization or cause clinical manifestations in terms of allergic contact dermatitis (ACD). METHODS: Dimethylglyoxime (DMG) spot tests assessed nickel release from several common utensils used in everyday life in São Paulo and Rio de Janeiro, Brazil. RESULTS: We tested 46 coins (two denominations) and 90 common utensils. Approximately 91.1% produced nickel-positive results using the DMG spot test. CONCLUSIONS: The DMG limit of detection was 1.67 ppm of nickel. We observed that many objects in our test series released nickel above the DMG test limit. This observation suggests that nickel-sensitive individuals may be exposed to nickel, representing a public health issue.


Asunto(s)
Dermatitis Alérgica por Contacto/etiología , Artículos Domésticos , Níquel/análisis , Brasil , Seguridad de Productos para el Consumidor , Humanos , Níquel/efectos adversos , Numismática , Oximas
3.
Int J Biol Macromol ; 140: 294-302, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31422188

RESUMEN

Several plants have been studied for their medicinal properties, especially concerning the management of chronic diseases, such as diabetes, aiming at a more accessible form of treatment. In this context, the aim of this study was to characterize plant proteins used in folk medicine as hypoglycemic agents for the treatment of diabetes, namely "abajerú" (Chrysobalanus icaco) and "cow's paw" (Bauhinia forficata and Bauhinia variegata). The species were differentiated by proteome characterization. Proteins were in-solution digested using trypsin by the filter-assisted sample preparation (FASP) method. Peptides were then analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS) for protein characterization. In total, 131 proteins were identified. The main biological functions of these proteins were cellular respiration, transport, metabolism and photosynthesis. Insulin-like proteins were not detected, but proteins involved in controlling glucose levels were. The results are of value in the proteomic characterization of phytotherapeutic plants, and may serve as baseline for the assessed species in Brazil, where a lack of knowledge in this regard is observed.


Asunto(s)
Bauhinia/metabolismo , Chrysobalanaceae/metabolismo , Diabetes Mellitus/tratamiento farmacológico , Hipoglucemiantes/farmacología , Extractos Vegetales/farmacología , Proteoma , Brasil , Cromatografía Liquida , Geografía , Hipoglucemiantes/química , Medicina Tradicional , Extractos Vegetales/química , Hojas de la Planta/metabolismo , Plantas Medicinales , Proteómica , Espectrometría de Masas en Tándem
4.
Int J Environ Res Public Health ; 11(11): 11528-40, 2014 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-25386955

RESUMEN

The objective of the present study was to investigate the reduction of mobility, availability and toxicity found in soil contaminated with lead (Pb) and cadmium (Cd) from Santo Amaro Municipality, Bahia, Brazil using two combined methods, commonly tested separately according to the literature: metal mobilization with phosphates and phytoextraction. The strategy applied was the treatment with two sources of phosphates (separately and mixed) followed by phytoremediation with vetiver grass (Vetiveria zizanioides (L.)). The treatments applied (in triplicates) were: T1-potassium dihydrogen phosphate (KH2PO4); T2-reactive natural phosphate fertilizer (NRP) and; T3-a mixture 1:1 of KH2PO4 and NRP. After this step, untreated and treated soils were planted with vetiver grass. The extraction procedures and assays applied to contaminated soil before and after the treatments included metal mobility test (TCLP); sequential extraction with BCR method; toxicity assays with Eisenia andrei. The soil-to-plant transfer factors (TF) for Pb and Cd were estimated in all cases. All treatments with phosphates followed by phytoremediation reduced the mobility and availability of Pb and Cd, being KH2PO4 (T1) plus phytoremediation the most effective one. Soil toxicity however, remained high after all treatments.


Asunto(s)
Cadmio/toxicidad , Contaminación Ambiental/prevención & control , Restauración y Remediación Ambiental/métodos , Plomo/toxicidad , Fosfatos/química , Contaminantes del Suelo/toxicidad , Biodegradación Ambiental , Disponibilidad Biológica , Cadmio/química , Cadmio/metabolismo , Fertilizantes/análisis , Plomo/química , Plomo/metabolismo , Compuestos de Potasio/química , Contaminantes del Suelo/química , Contaminantes del Suelo/metabolismo
5.
Environ Res ; 119: 88-100, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22901765

RESUMEN

Anthropogenic activities influence the biogeochemical cycles of mercury, both qualitatively and quantitatively, on a global scale from sources to sinks. Anthropogenic processes that alter the temporal and spatial patterns of sources and cycling processes are changing the impacts of mercury contamination on aquatic biota and humans. Human exposure to mercury is dominated by the consumption of fish and products from aquaculture operations. The risk to society and to ecosystems from mercury contamination is growing, and it is important to monitor these expanding risks. However, the extent and manner to which anthropogenic activities will alter mercury sources and biogeochemical cycling in tropical and sub-tropical coastal environments is poorly understood. Factors as (1) lack of reliable local/regional data; (2) rapidly changing environmental conditions; (3) governmental priorities and; (4) technical actions from supra-national institutions, are some of the obstacles to overcome in mercury cycling research and policy formulation. In the tropics and sub-tropics, research on mercury in the environment is moving from an exploratory "inventory" phase towards more process-oriented studies. Addressing biodiversity conservation and human health issues related to mercury contamination of river basins and tropical coastal environments are an integral part of paragraph 221 of the United Nations document "The Future We Want" issued in Rio de Janeiro in June 2012.


Asunto(s)
Ecosistema , Mercurio/química , Agua de Mar/química , Clima Tropical , Contaminantes Químicos del Agua/química , Animales , Bacterias/metabolismo , Exposición a Riesgos Ambientales , Monitoreo del Ambiente , Humanos , Mercurio/metabolismo , Microbiología del Agua , Contaminantes Químicos del Agua/metabolismo
6.
Environ Res ; 111(1): 156-63, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20943219

RESUMEN

BACKGROUND: Growing evidence suggests that excess manganese (Mn) in children is associated with neurobehavioral impairments. In Brazil, elevated hair Mn concentrations were reported in children living near a ferro-manganese alloy plant. OBJECTIVES: We investigated these children's and caregivers' cognitive function in relation to bioindicators of Mn exposure. METHODS: In this cross-sectional study, the WISC-III was administered to 83 children aged between 6 and 12 years; the Raven Progressive Matrix was administered to the primary caregivers (94% mothers), who likewise responded to a questionnaire on socio demographics and birth history. Mn in hair (MnH) and blood (MnB) and blood lead (PbB) were measured by graphite furnace atomic absorption spectrometry (GFAAS). RESULTS: Children's mean MnB and MnH were 8.2 µg/L (2.7-23.4) and 5.83 µg/g (0.1-86.68), respectively. Mean maternal MnH was 3.50 µg/g (0.10-77.45) and correlated to children's MnH (rho=0.294, p=0.010). Children's MnH was negatively related to Full-Scale Intelligence Quotient (IQ) and Verbal IQ; ß coefficients for MnH were -5.78 (95% CI -10.71 to -0.21) and -6.72 (-11.81 to -0.63), adjusted for maternal education and nutritional status. Maternal MnH was negatively associated with performance on the Raven's (ß=-2.69, 95% CI -5.43 to 0.05), adjusted for education years, family income and age. CONCLUSIONS: These findings confirm that high MnH in children is associated with poorer cognitive performance, especially in the verbal domain. Primary caregiver's IQ is likewise associated to Mn exposure, suggesting that, in this situation, children's cognition may be affected directly and indirectly by Mn exposure.


Asunto(s)
Trastornos del Conocimiento/inducido químicamente , Cognición/efectos de los fármacos , Exposición a Riesgos Ambientales/efectos adversos , Cabello/química , Intoxicación por Manganeso/psicología , Manganeso/metabolismo , Brasil , Niño , Trastornos del Conocimiento/sangre , Trastornos del Conocimiento/metabolismo , Estudios Transversales , Femenino , Humanos , Masculino , Manganeso/sangre , Intoxicación por Manganeso/sangre , Intoxicación por Manganeso/metabolismo , Madres , Factores Socioeconómicos , Estadísticas no Paramétricas
7.
Bull Environ Contam Toxicol ; 85(3): 274-8, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20690017

RESUMEN

The co-treatment from Morro do Céu landfill leachate with domestic sewage in the Icaraí STP was monitored with regard to the behavior of toxicity of its inflows and outflow. Leachate not exceeded 1.5% in volume in the plant. The acute ecotoxicological tests showed that, although leachate is far more harmful to D. rerio (LC50 approximately = 4) and D. similis (LC50 approximately = 5) than sewage (LC50 approximately = 62; LC50 approximately = 22), statistically the mixture of leachate with sewage did not result in a more toxic inflow (LC50 approximately = 57; LC50 approximately = 12) for treatment than raw sewage. After treatment, the outflow toxicity (LC50 approximately = 76; LC50 approximately = 16) complied with the environmental laws.


Asunto(s)
Daphnia/efectos de los fármacos , Aguas del Alcantarillado , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/toxicidad , Pez Cebra/fisiología , Animales , Ciudades , Pruebas de Toxicidad , Contaminantes Químicos del Agua/análisis
8.
Rev. panam. salud pública ; 26(6): 541-548, dic. 2009. tab
Artículo en Inglés | LILACS | ID: lil-536495

RESUMEN

OBJECTIVES: Manganese (Mn) is an essential element, but overexposure can have neurotoxic effects. METHODS: In this article, we review and summarize studies on exposure to Mn and nervous system impairments in children. RESULTS: We identified 12 original articles published between 1977 and 2007. Overexposure to Mn was suspected to occur through diverse sources: infant milk formula, drinking water, industrial pollution, and mining wastes. The most common bioindicator of exposure to Mn was hair Mn content, but some studies measured Mn in blood, urine, or dentin; one study on prenatal exposure measured Mn content in cord blood. Most studies indicate that higher postnatal exposure to Mn is associated with poorer cognitive functions and hyperactive behavior. CONCLUSIONS: The limitations of the existing studies are numerous: most were cross-sectional, had a modest sample size, and lacked adjustment for important confounders. Future investigations should be performed on a larger sample size and include a more detailed exposure assessment, addressing multiple sources of exposure such as food, water, and airborne particulates.


OBJETIVO: El manganeso (Mn) es un elemento esencial, pero la sobreexposición puede tener efectos neurotóxicos. MÉTODOS: En este artículo se hace una revisión y un compendio de los estudios publicados sobre la exposición al Mn y los trastornos del sistema nervioso en niños. RESULTADOS: Se identificaron 12 artículos originales publicados entre 1977 y 2007. La sobreexposición al Mn puede haber ocurrido a partir de diversas fuentes: leche en polvo o maternizada, agua de beber, polución industrial y desechos de la producción minera. El bioindicador de exposición utilizado con mayor frecuencia fue el contenido de Mn en el pelo, aunque algunos estudios lo midieron en la sangre, la orina o la dentina; un estudio sobre exposición prenatal midió su contenido en la sangre del cordón umbilical. La mayoría de los estudios indican que una mayor exposición posnatal al Mn se asocia con deficiencias en las funciones cognitivas y el comportamiento hiperactivo. CONCLUSIONES: Las limitaciones de los estudios publicados son numerosas: la mayoría de ellos eran transversales, se basaban en muestras pequeñas y en ellos no se ajustaron los resultados por importantes factores de confusión. Se requieren investigaciones adicionales con muestras mayores y que hagan una evaluación más detallada de la exposición, tomando en cuenta múltiples fuentes, como los alimentos, el agua y las partículas suspendidas en el aire.


Asunto(s)
Adolescente , Niño , Humanos , Exposición a Riesgos Ambientales/efectos adversos , Intoxicación por Manganeso/etiología , Intoxicación por Manganeso/epidemiología
9.
Neurotoxicology ; 30(6): 1207-13, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19393689

RESUMEN

Manganese (Mn) is an essential element, but an effective toxic at high concentrations. While there is an extensive literature on occupational exposure, few studies have examined adults and children living near important sources of airborne Mn. The objective of this study was to analyze hair Mn of children living in the vicinity of a ferro-manganese alloy production plant in the Great Salvador region, State of Bahia, Brazil and examine factors that influence this bioindicator of exposure. We examined 109 children in the age range of 1-10 years, living near the plant. Four separate housing areas were identified a priori on the bases of proximity to the emission sources and downwind location. A non-exposed group (n=43) of similar socio-economic status was also evaluated. Mn hair (MnH) concentration was measured by graphite atomic absorption spectrometry (GFAAS). Possible confounding hematological parameters were also assessed. Mean MnH concentration was 15.20 microg/g (1.10-95.50 microg/g) for the exposed children and 1.37 microg/g (0.39-5.58 microg/g) for the non-exposed. For the former, MnH concentrations were 7.95+/-1.40 microg/g (farthest from the plant), 11.81+/-1.11 microg/g (mid-region), 34.43+/-8.66 microg/g (closest to the plant) and 34.22+/-9.15 microg/g (directly downwind). Multiple regression analysis on log transformed MnH concentrations for the exposed children derived a model that explained 36.8% of the variability. In order of importance, area of children's residence, gender (girls>boys) and time of mother's residence in the area at the birth of the child, were significantly associated with MnH. Post hoc analyses indicated two groupings for exposure areas, with those living closest to and downwind of the plant displaying higher MnH concentrations compared to the others. The contribution of the time the mother lived in the community prior to the child's birth to the children's current MnH suggests that in utero exposure may play a role. A study of neurobehavioral performance with respect to Mn exposure in these children is currently underway.


Asunto(s)
Exposición a Riesgos Ambientales , Cabello/metabolismo , Hierro/metabolismo , Manganeso/metabolismo , Anemia/inducido químicamente , Brasil , Niño , Preescolar , Estudios Transversales , Exposición a Riesgos Ambientales/estadística & datos numéricos , Monitoreo del Ambiente , Contaminantes Ambientales/análisis , Femenino , Humanos , Lactante , Hierro/sangre , Hierro/toxicidad , Masculino , Manganeso/sangre , Manganeso/toxicidad , Estudios Retrospectivos , Población Urbana/estadística & datos numéricos
10.
Rev Panam Salud Publica ; 26(6): 541-8, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20107709

RESUMEN

OBJECTIVES: Manganese (Mn) is an essential element, but overexposure can have neurotoxic effects. METHODS: In this article, we review and summarize studies on exposure to Mn and nervous system impairments in children. RESULTS: We identified 12 original articles published between 1977 and 2007. Overexposure to Mn was suspected to occur through diverse sources: infant milk formula, drinking water, industrial pollution, and mining wastes. The most common bioindicator of exposure to Mn was hair Mn content, but some studies measured Mn in blood, urine, or dentin; one study on prenatal exposure measured Mn content in cord blood. Most studies indicate that higher postnatal exposure to Mn is associated with poorer cognitive functions and hyperactive behavior. CONCLUSIONS: The limitations of the existing studies are numerous: most were cross-sectional, had a modest sample size, and lacked adjustment for important confounders. Future investigations should be performed on a larger sample size and include a more detailed exposure assessment, addressing multiple sources of exposure such as food, water, and airborne particulates.


Asunto(s)
Exposición a Riesgos Ambientales/efectos adversos , Intoxicación por Manganeso/etiología , Adolescente , Niño , Humanos , Intoxicación por Manganeso/epidemiología
12.
Environ Pollut ; 156(3): 974-9, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18524439

RESUMEN

This article examines the advantages of the use of biomarkers as environmental indicators by applying it to Paraiba do Sul watershed, one of the most important Brazilian water bodies, which is in a critical environmental situation. We use a multibiomarker approach in fish as an integrated strategy to assess the impact of pollution. It comprehends a general biomarker of fish health, the condition factor (CF), and specific biomarkers of contaminant exposure such as metallothionein (MT), acetylcholinesterase (AChE) activity and biliary polycyclic aromatic hydrocarbons (PAH) metabolites. Our results revealed different effects in the fish from diverse locations with varying degrees of pollution. Furthermore, fish located just upstream of the water-treatment plant of the metropolitan area of Rio de Janeiro has shown to be affected by metals. This study indicates the usefulness of integrating a set of biomarkers to define the effects of anthropogenic inputs in aquatic bodies under complex polluted situations.


Asunto(s)
Cíclidos/metabolismo , Monitoreo del Ambiente/métodos , Plaguicidas/toxicidad , Contaminantes Químicos del Agua/toxicidad , Contaminación del Agua/análisis , Acetilcolinesterasa/análisis , Agricultura , Animales , Bilis/química , Biomarcadores/análisis , Brasil , Hígado/química , Metalotioneína/análisis , Microscopía Fluorescente , Músculos/enzimología , Ríos
13.
Sci Total Environ ; 399(1-3): 186-92, 2008 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-18468656

RESUMEN

Paraiba do Sul watershed is one of the most important Brazilian water bodies (5.5 million people depend on the river). It is in a critical environmental situation, polluted by industrial discharges, non-treated urban wastes, and pesticides, which have had cumulatively negative effects. This study analyzes the effects of pollution, with a biomarker approach, by using the invasive fish species, Oreochromis niloticus, as a sentinel species. The approach comprehends a general biomarker of the health of individual fish, the condition factor, a biomarker of genotoxicity, the micronuclei test; and specific biomarkers of contaminant exposure such as metallothionein (MT) and acetylcholinesterase (AChE) activity. The results revealed different effects in fish from diverse locations with varying degrees of pollution. Low AChE activities were found in fish from the region with strong agriculture activity, showing the effects of pesticides. Fish from an industrialized and heavily environmentally degraded area presented high levels of MT and low AChE activities, indicating an intricate polluted condition. It is noteworthy that fish located just upstream of the main water-treatment plant of the metropolitan area Rio de Janeiro presented high levels of MT, showing to be affected by metals. This can be an alert to public health officials. O. niloticus has proven a suitable sentinel species to assess the effects of pollutions in an aquatic system with a complex and serious polluted situation. The present study also shows the usefulness of integrating a set of biomarkers to define the exposure and the effects of anthropogenic inputs among impacted and reference sites in this water body.


Asunto(s)
Biomarcadores/análisis , Cíclidos/metabolismo , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisis , Acetilcolinesterasa/análisis , Acetilcolinesterasa/metabolismo , Animales , Biomarcadores/metabolismo , Brasil , Peces , Geografía , Metalotioneína/análisis , Metalotioneína/metabolismo , Medición de Riesgo , Ríos , Contaminantes Químicos del Agua/metabolismo
14.
J Hazard Mater ; 142(1-2): 389-96, 2007 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-17010512

RESUMEN

The levels of 21 polycyclic aromatic hydrocarbons (PAHs) with molecular weights between 128 Da (naphthalene) and 300 Da (coronene) were determined in Terminalia catappa L. (Combretaceae) bark. Tree bark samples were collected in the campus of Oswaldo Cruz Foundation, a green area located in a very intensive traffic area of Rio de Janeiro City, Brazil and about 10 km away from the city center. Samples were submitted to ultrasonic extraction with dichloromethane and analyzed by high-resolution gas chromatography-mass spectrometry. Individual PAH levels varied from 1.23 to 327 ng/g and phenanthrene, fluoranthene and pyrene predominated in all samples. Total PAH levels ranged from 242 to 1640 ng/g with a mean of 628 ng/g. The levels of total PAHs and of total carcinogenic PAHs showed not a clear dependence with tree location and distances to the main routes of that area. No correlation was observed also with PAH levels previously found in total suspended particulate thus indicating that in this area tree bark PAH levels cannot be used to assess their atmospheric levels.


Asunto(s)
Contaminantes Atmosféricos/análisis , Corteza de la Planta/química , Compuestos Policíclicos/análisis , Terminalia/química , Emisiones de Vehículos , Brasil , Cromatografía de Gases y Espectrometría de Masas , Transportes
15.
Int J Occup Environ Health ; 12(4): 400-7, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17168229

RESUMEN

In an agricultural region of Rio de Janeiro State, Brazil, rapid assessment procedures were used for risk-perception studies based on methodologic triangulation that included semi-structured interviews, participatory observations, and focus groups. Data were qualitatively categorized. Women's risk perception was prioritized, as they did not recognize some risks they were exposed to during work activities. To reach women likely to be exposed to pesticides, a photographic soap opera (fotonovela) was constructed in collaboration with rural workers, using community-based participatory research methods. Contents of the risk-communication strategies included the harmful effects of pesticides. Results showed that the inclusion of risk-perception studies in the development of educative and risk-communication campaigns is very important, bridging research to action.


Asunto(s)
Plaguicidas , Brasil , Exposición a Riesgos Ambientales , Femenino , Humanos , Masculino , Medición de Riesgo
16.
Environ Res ; 91(3): 143-50, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12648476

RESUMEN

Organochlorine (OC) plasma levels and their dietary and reproductive determinants were investigated in 64 pregnant women from Rio de Janeiro, Brazil. Prenatal exposure of newborns was evaluated in a subset of these women in which umbilical cord blood was analyzed. To assess the influence of dietary factors on OC levels, a semiquantitative food frequency questionnaire was completed by participants. Nondietary determinants were investigated through a general questionnaire that addressed reproductive history, lifestyle, and social-demographic characteristics. Both women and their newborns had detectable but low levels of OCs. The most frequently detected compound was p,p'-DDE, the main metabolite of p,p'-DDT. This compound was found in 97% of the women who participated in the study and in 67% of the umbilical cord blood samples, with levels ranging from 0.161 to 8.03ppb and from 0.320 to 1.06ppb, respectively. Among the OCs detected, only p,p'-DDE showed any correlation with dietary and nondietary factors. There was a positive correlation between maternal p,p'-DDE and the consumption of fish (Pearson r=0.38,P=0.002) and chicken (Pearson r=0.26, P=0.042). The correlation between pork consumption and p,p'-DDE exhibited an inverse relationship (Pearson r=-0.25,P=0.052). Parity was the only nondietary factor that showed a significant correlation (Pearson r=-0.36,P=0.004). The main determinants of p,p'-DDE levels in this group of women were fish consumption and parity, together explaining 28% of the variance (P<001), in a multivariate model.


Asunto(s)
Dieta , Contaminantes Ambientales/sangre , Insecticidas/sangre , Exposición Materna/estadística & datos numéricos , Adulto , Animales , Brasil/epidemiología , Estudios Transversales , Diclorodifenil Dicloroetileno/sangre , Femenino , Sangre Fetal/química , Contaminación de Alimentos , Humanos , Exposición Materna/efectos adversos , Carne , Embarazo , Reproducción , Encuestas y Cuestionarios
17.
Environ Sci Technol ; 36(7): 1625-9, 2002 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-11999075

RESUMEN

The sorption of lead by synthetic hydroxyapatite (HA) from solutions containing Pb2+ initial concentrations up to 1770 mg L(-1) was studied. X-ray diffractometry (XRD) associated with Rietveld methodology for refining the spectra pattern was used in order to characterize the mechanisms of lead uptake. It is shown that the dissolution of hydroxyapatite is followed by the formation of a solid solution, Pb(10-x)Ca(x)(PO4)6(OH)2, with Pb ions mostly occupying Ca(II) sites. The Ca/Pb molar ratio of this solid solution decreases continuously until it reaches the structure of a pure hydroxypyromorphite. The cell parameters and the crystallite mean size behavior of both mineral phases reinforce the hypothesis that hydroxypyromorphite, PbHA, formation is the end of a process in which Pb(10-x)Ca(x)(PO4)6(OH)2 crystallites are continuously dissolved and recrystallized producing crystals with lower calcium content. Combination of Inductively Coupled Plasma spectrometry (ICP), chemical analysis, and XRD results permitted the conclusion that lead ions are not completely immobilized by precipitating Pb(10-x)Ca(x)(PO4)6(OH)2. Additional surface mechanisms also contribute to Pb2+ uptake. During Pb2+ sorption process, pH variations of the solution phase showed a more complex pattern than previously reported. Contribution of surface mechanisms, in addition to the hydroxyapatite dissolution, could explain this behavior.


Asunto(s)
Materiales Biocompatibles/química , Durapatita/química , Plomo/química , Cristalización , Contaminación Ambiental/prevención & control , Solubilidad , Difracción de Rayos X
18.
Ciênc. Saúde Colet. (Impr.) ; 7(2): 299-311, 2002. tab, graf
Artículo en Portugués | LILACS | ID: lil-334715

RESUMEN

O impacto do uso de agrotóxicos sobre a saúde humana é um problema que tem merecido atenção da comunidade científica em todo o mundo, sobretudo nos países em desenvolvimento. O consumo de agrotóxicos na região sudeste do Brasil está estimado em 12kg de agrotóxico/trabalhador/ano. Em algumas áreas agrícolas do Estado do Rio de Janeiro, como na região da Microbacia do Córrego de São Lourenço, Nova Friburgo, o consumo de agrotóxico foi estimado em 56kg de agrotóxico/trabalhador/ano. Elevados níveis de contaminação humana e ambiental foram encontrados nesta região, como decorrência do uso extensivo destes agentes químicos. A avaliação do impacto sobre a saúde humana implica o conhecimento e a visualização da importância/magnitude relativa de cada uma das vias de contaminação. Inúmeros fatores, que, em geral, encontram-se inter-relacionados, contribuem para a situação encontrada na Microbacia do Córrego de São Lourenço e a forma mais adequada de se avaliar toda a dimensão deste problema é o uso de uma abordagem integrada.


Asunto(s)
Trabajadores Rurales , Uso de Plaguicidas , Riesgos Laborales , Exposición a Plaguicidas , Impactos de la Polución en la Salud
19.
Rev. bras. toxicol ; 13(1): 63-8, jul. 2000. tab
Artículo en Portugués | LILACS | ID: lil-271861

RESUMEN

Na busca de um indicador biológico efetivo para estudo da exposição ao benzeno, em substituição ao fenol urinário, o ácido trans, trans-mucônico (ttAM) tem sido apresentado como excelente alternativa. Para comprovar este fato, este estudo foi realizado em trabalhadores expostos à baixas concentrações ambientais de benzeno. O grupo de estudo foi constituído por 36 frentistas e 37 mecânicos de automóveis o grupo de controle, por 50 trabalhadores de um edifício de escritórios. Entre os mecânicos, valores (média geométrica) de 0,43 ppm (0,08-0,90 ppm) de benzeno no ar e 1,05 mg/g creatinina (0,34-2,10 mg/g creatina) de ttAM foram encontrados. Entre os frentistas estes valores foram 0,31 ppm (0,04-0,70 ppm) e 0,97 mg/g creatina (0,2-2,0 mg/g creatina) respectivamente. A correlação observada: r = 0,88 (p<0,001); y =0,7076x + 0,3134, r2 = 0,78 sugere que o ttAM é um bom parâmetro para estimar a exposição de benzeno mesmo a baixas concentrações ambientais.


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Benceno/toxicidad , Exposición Profesional/efectos adversos , Ácido Sórbico , Contaminantes Ocupacionales del Aire/efectos adversos , Brasil , Cromatografía de Gases , Creatinina/orina , Conservantes de Alimentos , Riesgos Laborales
20.
Cad. saúde pública ; 15(4): 845-50, out.-dez. 1999. tab, graf
Artículo en Portugués | LILACS | ID: lil-260022

RESUMEN

Várias substâncias químicas com atividade sobre o sistema endócrino têm sido amplamente utilizadas no Brasil tanto em atividades industriais quanto em outros ramos, como por exemplo, na agricultura. Alguns dados mostrando a contaminaçäo de grupos populacionais brasileiros por substâncias supostamente possuidoras destas propriedades säo apresentados. Entretanto, muito pouco, ou mesmo nada, se sabe sobre os efeitos que as mesmas têm sobre a saúde destas populaçöes expostas, mostrando claramente a necessidade urgente de implementaçäo de um programa destinado a esta finalidade.


Asunto(s)
Sistema Endocrino , Exposición a Riesgos Ambientales , Ambiente
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