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1.
Environ Health Perspect ; 124(4): 477-83, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26383636

RESUMO

BACKGROUND: Blooms of marine phytoplankton may adversely affect human health. The potential public health impact of low-level exposures is not well established, and few prospective cohort studies of recreational exposures to marine phytoplankton have been conducted. OBJECTIVE: We evaluated the association between phytoplankton cell counts and subsequent illness among recreational beachgoers. METHODS: We recruited beachgoers at Boquerón Beach, Puerto Rico, during the summer of 2009. We conducted interviews at three time points to assess baseline health, water activities, and subsequent illness. Daily water samples were quantitatively assayed for phytoplankton cell count. Logistic regression models, adjusted for age and sex, were used to assess the association between exposure to three categories of phytoplankton concentration and subsequent illness. RESULTS: During 26 study days, 15,726 individuals successfully completed all three interviews. Daily total phytoplankton cell counts ranged from 346 to 2,012 cells/mL (median, 712 cells/mL). The category with the highest (≥ 75th percentile) total phytoplankton cell count was associated with eye irritation [adjusted odds ratio (OR) = 1.30; 95% confidence interval (CI): 1.01, 1.66], rash (OR = 1.27; 95% CI: 1.02, 1.57), and earache (OR = 1.25; 95% CI: 0.88, 1.77). In phytoplankton group-specific analyses, the category with the highest Cyanobacteria counts was associated with respiratory illness (OR = 1.37; 95% CI: 1.12, 1.67), rash (OR = 1.32; 95% CI: 1.05, 1.66), eye irritation (OR = 1.25; 95% CI: 0.97, 1.62), and earache (OR = 1.35; 95% CI: 0.95, 1.93). CONCLUSIONS: We found associations between recreational exposure to marine phytoplankton and reports of eye irritation, respiratory illness, and rash. We also found that associations varied by phytoplankton group, with Cyanobacteria having the strongest and most consistent associations. CITATION: Lin CJ, Wade TJ, Sams EA, Dufour AP, Chapman AD, Hilborn ED. 2016. A prospective study of marine phytoplankton and reported illness among recreational beachgoers in Puerto Rico, 2009. Environ Health Perspect 124:477-483; http://dx.doi.org/10.1289/ehp.1409558.


Assuntos
Praias/estatística & dados numéricos , Exantema/microbiologia , Oftalmopatias/microbiologia , Fitoplâncton/isolamento & purificação , Doenças Respiratórias/microbiologia , Água do Mar/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos de Coortes , Cianobactérias/isolamento & purificação , Exposição Ambiental/estatística & dados numéricos , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Porto Rico , Recreação , Água do Mar/efeitos adversos
2.
Appl Environ Microbiol ; 79(18): 5601-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23851084

RESUMO

Our understanding of the sources of Mycobacterium avium infection is partially based on genotypic matching of pathogen isolates from cases and environmental sources. These approaches assume that genotypic identity is rare in isolates from unlinked cases or sources. To test this assumption, a high-resolution PCR-based genotyping approach, large-sequence polymorphism (LSP)-mycobacterial interspersed repetitive unit-variable-number tandem repeat (MIRU-VNTR), was selected and used to analyze clinical and environmental isolates of M. avium from geographically diverse sources. Among 127 clinical isolates from seven locations in North America, South America, and Europe, 42 genotypes were observed. Among 12 of these genotypes, matches were seen in isolates from apparently unlinked patients in two or more geographic locations. Six of the 12 were also observed in environmental isolates. A subset of these isolates was further analyzed by alternative strain genotyping methods, pulsed-field gel electrophoresis and MIRU-VNTR, which confirmed the existence of geographically dispersed strain genotypes. These results suggest that caution should be exercised in interpreting high-resolution genotypic matches as evidence for an acquisition event.


Assuntos
Microbiologia Ambiental , Variação Genética , Tipagem Molecular/métodos , Mycobacterium avium/classificação , Mycobacterium avium/genética , Tuberculose/epidemiologia , Tuberculose/microbiologia , DNA Bacteriano/química , DNA Bacteriano/genética , Europa (Continente) , Genótipo , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Mycobacterium avium/isolamento & purificação , América do Norte , Análise de Sequência de DNA , América do Sul
3.
Toxicon ; 48(6): 627-40, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16952386

RESUMO

In 1996, an extensive exposure of Brazilian hemodialysis patients at a dialysis center, using a municipal water supply water contaminated with cyanotoxins, provided the first evidence for acute lethal human poisoning from the cyclic peptide hepatotoxins called microcystins. During this outbreak, 100 of 131 patients developed acute liver failure and 52 of these victims were confirmed to have been exposed to lethal levels of microcystins. Detection and quantitation of microcystins in these biological samples posed some analytical challenges since there were no well-established and routine analytic methods to measure total microcystins in tissue or sera samples. At the time of the 1996 exposure we used analytic methods that combined the use of enzyme linked immunosorbant assay (ELISA), analytical high performance liquid chromatography (HPLC), electrospray ionization ion-trap mass spectroscopy (ES-ITMS) and matrix assisted laser desorption ionization-time of flight spectroscopy (MALDI-TOF). In the intervening years these methods have been improved and others developed that allow a more quantitative and critical analysis of microcystin contaminated tissue and sera. For these reasons, and to see how storage with time might effect the detection and stability of microcystins in these matrices, we reanalyzed selected liver tissues and sera from the Caruaru victims in Brazil. We developed and validated a procedure to measure total microcystins in Caruaru human sera and liver tissue using a combination of ELISA, liquid chromatography and liquid chromatography-mass spectrometry (LC/MS), GC/MS and MS/MS techniques. GC/MS and LC/MS were followed by MS/MS to obtain a fingerprint fragment spectra for the microcystins. The validity of the extraction procedure for free microcystins was confirmed by recovery experiments with blood sera spiked with microcystin-LR. We removed proteins with the Microcon Centrifugal Filter prior to LC/MS and ELISA analysis. A solid phase extraction (SPE) procedure was used for analysis of protein bound microcystins by conversion of ADDA to erythro-2-methyl-3-methoxy-4-phenylbutyric acid (MMPB) combined with GC/MS. We found that the GC/MS method yielded a higher concentration of microcystin than that obtained by ELISA and LC/MS. We hypothesize that this difference is due to better GC/MS detection of the covalently bound form of microcystins in human liver tissue. We also concluded that microcystins are very stable when stored under these conditions for periods of almost 10 years.


Assuntos
Toxinas Bacterianas/análise , Toxinas Bacterianas/intoxicação , Fígado/química , Microcistinas/análise , Microcistinas/intoxicação , Microbiologia da Água , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/intoxicação , Toxinas Bacterianas/sangue , Brasil/epidemiologia , Cromatografia Líquida/métodos , Surtos de Doenças , Estudos Epidemiológicos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Falência Hepática Aguda/epidemiologia , Falência Hepática Aguda/mortalidade , Espectrometria de Massas/métodos , Microcistinas/sangue , Poluentes Químicos da Água/sangue , Abastecimento de Água
4.
Environ Toxicol ; 21(2): 95-103, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16528683

RESUMO

In November 2001, a cyanobacterial bloom dominated by Microcystis and Anabaena occurred in the Funil Reservoir and the Guandu River, both of which supply drinking water to Rio de Janeiro, Brazil. Using ELISA, microcystins were detected at a concentration of 0.4 microg/L in the drinking water, whereas a concentration of 0.32 microg/L was detected in activated carbon column-treated water for use at the renal dialysis center of Clementino Fraga Filho Hospital (HUCFF) at the Federal University of Rio de Janeiro. A total of 44 hemodialysis patients who received care at this center were believed to be exposed. Initial ELISA analyses confirmed the presence of serum microcystin concentrations > or = 0.16 ng/mL in 90% of serum samples collected from these patients. Twelve patients were selected for continued monitoring over the following 2-month period. Serum microcystin concentrations ranged from < 0.16 to 0.96 ng/mL during the 57 days after documented exposure. ELISA-positive samples were found throughout the monitoring period, with the highest values detected 1 month after initial exposure. ESI LC/MS analyses indicated microcystins in the serum; however, MS/MS fragmentation patterns typical of microcystins were not identified. LC/MS analyses of MMPB for control serum spiked with MCYST-LR. and patient sera revealed a peak at retention time of 8.4 min and a mass of 207 m/z. These peaks are equivalent to the peak observed in the MMPB standard analysis. Taken together ELISA, LC/MS, and MMPB results indicate that these renal dialysis patients were exposed to microcystins. This documents another incident of human microcystin exposure during hemodialysis treatment.


Assuntos
Toxinas Bacterianas/intoxicação , Exposição Ambiental , Peptídeos Cíclicos/intoxicação , Insuficiência Renal/complicações , Toxemia/microbiologia , Microbiologia da Água , Toxinas Bacterianas/sangue , Brasil , Ensaio de Imunoadsorção Enzimática , Unidades Hospitalares de Hemodiálise , Humanos , Microcistinas , Microcystis/isolamento & purificação , Peptídeos Cíclicos/análise , Peptídeos Cíclicos/sangue , Diálise Renal , Toxemia/complicações
5.
Toxicon ; 46(2): 218-21, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15963544

RESUMO

Toxic cyanobacteria are contaminants of surface waters worldwide. Microcystins are some of the most commonly detected cyanotoxins. Biological evidence of human exposure may be difficult to obtain due to limitations associated with cost, laboratory capacity, analytic support, and expertise. We investigated the application of an enzyme-linked immunosorbant assay (ELISA) to detect microcystins in human serum. We analyzed ten serum samples collected from dialysis patients who were known to be exposed to a mixture of microcystins during a 1996 outbreak in Brazil. We applied a commercially available ELISA method to detect microcystins in serum, and we compared the ELISA results to a more specific method, liquid chromatography/mass spectrometry (LC/MS) that was also used to detect microcystins in serum. The Spearman correlation coefficient was calculated using serum microcystin concentrations in split samples obtained by the two methods. Serum microcystin concentrations were similar, and we found good correlation of microcystin concentrations between the two methods. The ELISA detected total microcystins, median=19.9 ng/ml; LC/MS detected microcystin-LR equivalents, median=21.2 ng/ml; Spearman r=0.96, p<0.0001. We found that ELISA is a simple, accessible method to screen human serum for evidence of microcystin exposure.


Assuntos
Toxinas Bacterianas/isolamento & purificação , Análise Química do Sangue/métodos , Colorimetria/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Peptídeos Cíclicos/isolamento & purificação , Brasil , Cromatografia Líquida , Estudos de Avaliação como Assunto , Humanos , Espectrometria de Massas , Microcistinas
6.
Arch Environ Health ; 59(9): 467-70, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16381488

RESUMO

Field methods are needed to detect and monitor the organophosphate pesticide exposure of young children. Twenty children, aged 11 to 18 mo, living in an agricultural community along the United States/Mexico border were enrolled in a pilot study investigating methods to detect pesticide exposure. Healthy children were recruited at pediatric clinics with the informed consent of their parents. Venous blood samples were collected from children twice, 4 wk apart. Cholinesterase activity was compared in whole heparinized venous blood with venous blood samples dried on filter paper. Although the amount of activity in the dried blood was consistently less than in the heparinized blood, the activity was significantly correlated: Spearman r = .6 (p = 0.01). This dried blood method may be used during field studies to evaluate changes in cholinesterase values in children over time.


Assuntos
Colinesterases/metabolismo , Exposição Ambiental , Praguicidas/intoxicação , Fatores Etários , Colinesterases/análise , Feminino , Testes Hematológicos/métodos , Humanos , Lactente , Masculino , México , Intoxicação por Organofosfatos , População Rural , Estados Unidos
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