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1.
MMWR Morb Mortal Wkly Rep ; 72(45): 1225-1229, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37943708

RESUMO

In 2016, CDC identified a multidrug-resistant (MDR) strain of Salmonella enterica serotype Newport that is now monitored as a persisting strain (REPJJP01). Isolates have been obtained from U.S. residents in all 50 states and the District of Columbia, linked to travel to Mexico, consumption of beef products obtained in the United States, or cheese obtained in Mexico. In 2021, the number of isolates of this strain approximately doubled compared with the 2018-2020 baseline and remained high in 2022. During January 1, 2021- December 31, 2022, a total of 1,308 isolates were obtained from patients, cattle, and sheep; 86% were MDR, most with decreased susceptibility to azithromycin. Approximately one half of patients were Hispanic or Latino; nearly one half reported travel to Mexico during the month preceding illness, and one third were hospitalized. Two multistate outbreak investigations implicated beef products obtained in the United States. This highly resistant strain might spread through travelers, animals, imported foods, domestic foods, or other sources. Isolates from domestic and imported cattle slaughtered in the United States suggests a possible source of contamination. Safe food and drink consumption practices while traveling and interventions across the food production chain to ensure beef safety are necessary in preventing illness.


Assuntos
Farmacorresistência Bacteriana Múltipla , Salmonella enterica , Estados Unidos/epidemiologia , Humanos , Bovinos , Animais , Ovinos , México/epidemiologia , Salmonella , District of Columbia
2.
Environ Res ; 147: 307-13, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26922411

RESUMO

BACKGROUND: In recent years, pyrethroid pesticide use has increased in Mexico, the United States, and elsewhere, resulting in extensive human exposure. There is growing concern that pregnant women may be a particularly vulnerable population, as in utero fetal exposure during critical periods of development could adversely affect long-term neurobehavioral function. METHODS: We measured maternal urinary 3-phenoxybenzoic acid (3-PBA) concentrations during the third trimester of pregnancy as a measure of in utero pyrethroid exposure to the fetus among participants in an established Mexico City birth cohort (n=187). In a subset of mothers, we measured 3-PBA during the first, second, and third trimester (n=21) to assess variability across pregnancy. We examined associations between third trimester 3-PBA concentrations and children's scores on the Mental Development Index (MDI) and Psychomotor Development Index (PDI) from the Bayley Scales for Infant Development (BSID-IIS) at 24 and 36 months of age. RESULTS: 3-PBA was detected in 46% of all urine samples, with similar detection rates and geometric mean concentrations across pregnancy among the 21 participants who provided repeat samples. Participants in the medium and high 3-PBA categories (≥LOD) had lower MDI scores at 24 months compared to those in the low 3-PBA category (

Assuntos
Benzoatos/urina , Desenvolvimento Infantil/efeitos dos fármacos , Poluentes Ambientais/urina , Exposição Materna/efeitos adversos , Sistema Nervoso/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Benzoatos/efeitos adversos , Pré-Escolar , Poluentes Ambientais/efeitos adversos , Feminino , Humanos , Troca Materno-Fetal , México , Sistema Nervoso/embriologia , Sistema Nervoso/crescimento & desenvolvimento , Gravidez , Efeitos Tardios da Exposição Pré-Natal/psicologia , Efeitos Tardios da Exposição Pré-Natal/urina
3.
Environ Res ; 146: 191-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26775000

RESUMO

BACKGROUND: Paraquat and diquat are among the most commonly used herbicides in the world. OBJECTIVES: Determine the magnitude, characteristics, and root causes for acute paraquat- and diquat-related illnesses in the US METHODS: Illnesses associated with paraquat or diquat exposure occurring from 1998 through 2011 were identified from the Sentinel Event Notification System for Occupational Risks (SENSOR)-Pesticides Program, the California Department of Pesticide Regulation (CDPR) Pesticide Illness Surveillance Program (PISP), and the Incident Data System (IDS). Cases identified by the National Poison Data System (NPDS) were reviewed for the years 1998-2003 and 2006-2013. RESULTS: A total of 300 paraquat- and 144 diquat-related acute illnesses were identified by SENSOR, PISP, and IDS. NPDS identified 693 paraquat- and 2128 diquat-related acute illnesses. In SENSOR/PISP/IDS, illnesses were commonly low severity (paraquat=41%; diquat=81%); however, SENSOR/PISP/IDS identified 24 deaths caused by paraquat and 5 deaths associated with diquat. Nineteen paraquat-related deaths were due to ingestion, seven of which were unintentional, often due to improper storage in beverage bottles. In SENSOR/PISP/IDS, paraquat and diquat-related acute illnesses were work-related in 68% (n=203) and 29% (n=42) of cases, respectively. When herbicide application site was known, the vast majority of acute paraquat-related illnesses (81%) arose from agricultural applications. Common root causes of illness were failure to use adequate personal protective equipment (PPE), application equipment failure, and spill/splash of herbicide. CONCLUSIONS: Although the magnitude of acute paraquat/diquat-related illnesses was relatively low, several fatalities were identified. Many illnesses could be prevented through stricter compliance with label requirements (e.g. ensuring proper herbicide storage and PPE use), and through enhanced training of certified applicators.


Assuntos
Diquat/intoxicação , Exposição Ambiental , Herbicidas/intoxicação , Paraquat/intoxicação , Acidentes de Trabalho , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Estados Unidos , Adulto Jovem
4.
Environ Res ; 132: 342-9, 2014 07.
Artigo em Inglês | MEDLINE | ID: mdl-24834831

RESUMO

Globally, organophosphate (OP) pesticide usage and exposure is widespread. Studies have found that fetuses and infants are more sensitive than adults to environmental toxicants and that prenatal exposure to low levels of OPs has been associated with Attention Deficit Hyperactivity Disorder-Like Phenotypes (ADHD-LP). Paraoxonase 1 (PON1) is an enzyme involved in detoxifying some OPs and its polymorphisms influence enzyme activity and quantity. The objective of this study was to examine whether maternal and/or child PON1 genotypes (PON1R192Q and PON1L55M) were associated with ADHD-LP in a Mexico City, Mexico birth cohort. PON1R192Q and PON1L55M genotypes in mothers (PON1R192Q: N=531; PON1L55M: N=458) and children (PON1R192Q: N=532; PON1L55M: N=478) from blood DNA were determined. We assessed ADHD-LP for children between the ages of 6 and 13 using Conners' Parent Rating Scales-Revised (CRS-R), Conners' Continuous Performance Test (CPT), and the parent scores for Behavior Assessment System for Children-2 (BASC2). Multivariable linear regression models were used to test relationships between ADHD-LP and PON1 polymorphisms. In these models, significant associations were observed with maternal genotypes but not with the child genotypes. A higher DSM IV Hyperactivity/Impulsivity score (ß=3.27 points; 95% CI (0.89, 5.65)) and a 2.17 higher score in child DSM IV Total (95% CI (0.05, 4.29)) were observed for maternal PON155MM in comparison to PON155LM+LL. The childattention problems score was 2.27 points higher (95% CI (0.002, 4.53) for maternal PON1192QQ in comparison to PON1192QR+RR. Because maternal PON1 polymorphisms were associated with child ADHD-LP, this may be a viable biomarker of susceptibility for ADHD-LP.


Assuntos
Arildialquilfosfatase/genética , Transtorno do Deficit de Atenção com Hiperatividade/genética , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/induzido quimicamente , Criança , Feminino , Seguimentos , Predisposição Genética para Doença , Humanos , Masculino , México , Organofosfatos/efeitos adversos , Organofosfatos/metabolismo , Fenótipo , Polimorfismo de Nucleotídeo Único , Adulto Jovem
5.
PLoS One ; 19(3): e0299354, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38483966

RESUMO

The goal of this study is to investigate the origin, prevalence, and evolution of the pESI megaplasmid in Salmonella isolated from animals, foods, and humans. We queried 510,097 Salmonella genomes under the National Center for Biotechnology Information (NCBI) Pathogen Detection (PD) database for the presence of potential sequences containing the pESI plasmid in animal, food, and environmental sources. The presence of the pESI megaplasmid was confirmed by using seven plasmid-specific markers (rdA, pilL, SogS, TrbA, ipf, ipr2 and IncFIB(pN55391)). The plasmid and chromosome phylogeny of these isolates was inferred from single nucleotide polymorphisms (SNPs). Our search resolved six Salmonella clusters carrying the pESI plasmid. Four were emergent Salmonella Infantis clusters, and one each belonged to serovar Senftenberg and Alachua. The Infantis cluster with a pESI plasmid carrying blaCTX-M-65 gene was the biggest of the four emergent Infantis clusters, with over 10,000 isolates. This cluster was first detected in South America and has since spread widely in United States. Over time the composition of pESI in United States has changed with the average number of resistance genes showing a decrease from 9 in 2014 to 5 in 2022, resulting from changes in gene content in two integrons present in the plasmid. A recent and emerging cluster of Senftenberg, which carries the blaCTX-M-65 gene and is primarily associated with turkey sources, was the second largest in the United States. SNP analysis showed that this cluster likely originated in North Carolina with the recent acquisition of the pESI plasmid. A single Alachua isolate from turkey was also found to carry the pESI plasmid containing blaCTX-M-65 gene. The study of the pESI plasmid, its evolution and mechanism of spread can help us in developing appropriate strategies for the prevention and further spread of this multi-drug resistant plasmid in Salmonella in poultry and humans.


Assuntos
Salmonella enterica , Humanos , Animais , Estados Unidos , Sorogrupo , Antibacterianos/farmacologia , Resistência às Cefalosporinas/genética , Galinhas/genética , Virulência/genética , Salmonella , Plasmídeos/genética , Farmacorresistência Bacteriana Múltipla/genética
7.
Disaster Med Public Health Prep ; 16(3): 1279-1281, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-33148368

RESUMO

The need for increased testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19), has resulted in an increase of testing facilities outside of traditional clinical settings and sample handling by individuals without appropriate biohazard and biocontainment training. During the repatriation and quarantine of passengers from the Grand Princess cruise ship at a US military base, biocontainment of a potentially infectious sample from a passenger was compromised. This study describes the steps taken to contain the spill, decontaminate the area, and discusses the needs for adequate training in a biohazard response.


Assuntos
COVID-19 , Quarentena , Humanos , Quarentena/métodos , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2 , Substâncias Perigosas , Surtos de Doenças/prevenção & controle , Navios
8.
Foods ; 11(13)2022 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-35804790

RESUMO

Extraintestinal pathogenic Escherichia coli (ExPEC) cause urinary tract and potentially life-threatening invasive infections. Unfortunately, the origins of ExPEC are not always clear. We used genomic data of E. coli isolates from five U.S. government organizations to evaluate potential sources of ExPEC infections. Virulence gene analysis of 38,032 isolates from human, food animal, retail meat, and companion animals classified the subset of 8142 non-diarrheagenic isolates into 40 virulence groups. Groups were identified as low, medium, and high relative risk of containing ExPEC strains, based on the proportion of isolates recovered from humans. Medium and high relative risk groups showed a greater representation of sequence types associated with human disease, including ST-131. Over 90% of food source isolates belonged to low relative risk groups, while >60% of companion animal isolates belonged to medium or high relative risk groups. Additionally, 18 of the 26 most prevalent antimicrobial resistance determinants were more common in high relative risk groups. The associations between antimicrobial resistance and virulence potentially limit treatment options for human ExPEC infections. This study demonstrates the power of large-scale genomics to assess potential sources of ExPEC strains and highlights the importance of a One Health approach to identify and manage these human pathogens.

9.
Environ Health ; 9: 62, 2010 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-20955576

RESUMO

BACKGROUND: Presence of Bisphenol A (BPA) has been documented worldwide in a variety of human biological samples. There is growing evidence that low level BPA exposure may impact placental tissue development and thyroid function in humans. The aim of this present pilot study was to determine urinary concentrations of BPA during the last trimester of pregnancy among a small subset of women in Mexico City, Mexico and relate these concentrations to risk of delivering prematurely. METHODS: A nested case-control subset of 60 participants in the Early Life Exposure in Mexico to ENvironmental Toxicants (ELEMENT) study in Mexico City, Mexico were selected based on delivering less than or equal to 37 weeks of gestation and greater than 37 weeks of gestation. Third trimester archived spot urine samples were analyzed by online solid phase extraction coupled with high performance liquid chromatography isotope dilution tandem mass spectrometry. RESULTS: BPA was detected in 80.0% (N = 48) of the urine samples; total concentrations ranged from < 0.4 µg/L to 6.7 µg/L; uncorrected geometric mean was 1.52 µg/L. The adjusted odds ratio of delivering less than or equal to 37 weeks in relation to specific gravity adjusted third trimester BPA concentration was 1.91 (95%CI 0.93, 3.91, p-value = 0.08). When cases were further restricted to births occurring prior to the 37th week (n = 12), the odds ratio for specific-gravity adjusted BPA was larger and statistically significant (p < 0.05). CONCLUSIONS: This is the first study to document measurable levels of BPA in the urine of a population of Mexican women. This study also provides preliminary evidence, based on a single spot urine sample collected during the third trimester, that pregnant women who delivered less than or equal to 37 weeks of gestation and prematurely (< 37 weeks) had higher urinary concentrations of BPA compared to women delivering after 37 weeks.


Assuntos
Exposição Ambiental/efeitos adversos , Poluentes Ambientais/intoxicação , Fenóis/intoxicação , Nascimento Prematuro/induzido quimicamente , Adulto , Compostos Benzidrílicos , Estudos de Casos e Controles , Feminino , Humanos , Modelos Logísticos , México/epidemiologia , Fenóis/urina , Projetos Piloto , Gravidez , Terceiro Trimestre da Gravidez/efeitos dos fármacos , Terceiro Trimestre da Gravidez/urina , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/urina
10.
Curr Microbiol ; 59(1): 1-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19319600

RESUMO

Predation by Bdellovibrio-like organisms (BLOs) results in bacterial community succession in aquatic ecosystems. The effects of nutrient loading on the distribution and phylogeny of BLOs remain largely unknown. To this end, we present our findings on BLO diversity from four north-Indian lakes that are variable in their trophic status; Nainital is eutrophic, both, Bhimtal and Naukuchiatal are mesotrophic and Sattal remains oligotrophic, respectively. Initially, total heterotrophic bacteria and BLOs were quantified by most probable number (MPN) analyses using Pseudomonas putida and Escherichia coli as prey bacteria. Total bacterial numbers were at least two-logs higher in the eutrophic lake samples compared with oligotrophic lake. Similarly, BLO numbers were approximately 39-fold higher using Pseudomonas sp., which is likely the preferred prey within these lakes. Conversely, significant differences were not observed between mesotrophic and oligotrophic BLO numbers when E. coli was used as the prey. PCR-RFLP of small subunit rDNA (SSU rDNA) of BLOs, followed by cloning, sequencing, and taxonomic categorization revealed distinct differences such that, eutrophic lake consisted of higher BLO diversity compared with mesotrophic and oligotrophic lake, most likely due to both, higher numbers and availability of a diverse population of prey bacteria resulting from nutrient loading in this ecosystem.


Assuntos
Bactérias/isolamento & purificação , Bdellovibrio/isolamento & purificação , Biodiversidade , Eutrofização , Água Doce/microbiologia , Bactérias/classificação , Bactérias/genética , Bdellovibrio/classificação , Bdellovibrio/genética , DNA Bacteriano/genética , DNA Ribossômico/genética , Índia , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética
11.
Prehosp Disaster Med ; 33(3): 256-265, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29669608

RESUMO

OBJECTIVES: The Flint Community Resilience Group (Flint, Michigan USA) and the Centers for Disease Control and Prevention (CDC; Atlanta, Georgia USA) assessed behavioral health concerns among community members to determine the impact of lead contamination of the Flint, Michigan water supply. METHODS: A Community Assessment for Public Health Emergency Response (CASPER) was conducted from May 17 through May 19, 2016 using a multi-stage cluster sampling design to select households and individuals to interview. RESULTS: One-half of households felt overlooked by decision makers. The majority of households self-reported that at least one member experienced more behavioral health concerns than usual. The prevalence of negative quality of life indicators and financial concerns in Flint was higher than previously reported in the Michigan 2012 and 2014 Behavioral Risk Factor Surveillance System (BRFSS) survey. CONCLUSIONS: The following can be considered to guide recovery efforts in Flint: identifying additional resources for behavioral health interventions and conducting follow-up behavioral health assessments to evaluate changes in behavioral health concerns over time; considering the impact of household economic factors when implementing behavioral health interventions; and ensuring community involvement and engagement in recovery efforts to ease community stress and anxiety. FortenberryGZ, ReynoldsP, BurrerSL, Johnson-LawrenceV, WangA, SchnallA, PullinsP, KieszakS, BayleyegnT, WolkinA. Assessment of behavioral health concerns in the community affected by the Flint water crisis - Michigan (USA) 2016. Prehosp Disaster Med. 2018;33(3):256-265.


Assuntos
Comportamentos Relacionados com a Saúde , Intoxicação por Chumbo , Comportamento Problema , Água/efeitos adversos , Adolescente , Adulto , Idoso , Sistema de Vigilância de Fator de Risco Comportamental , Centers for Disease Control and Prevention, U.S. , Criança , Pré-Escolar , Demografia/estatística & dados numéricos , Feminino , Humanos , Intoxicação por Chumbo/psicologia , Masculino , Michigan , Pessoa de Meia-Idade , Autorrelato , Estados Unidos , Adulto Jovem
12.
Int J Hyg Environ Health ; 217(2-3): 405-12, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24001412

RESUMO

Attention Deficit Hyperactivity Disorder (ADHD) is the most commonly diagnosed and studied cognitive and behavioral disorder in school-age children. The etiology of ADHD and ADHD-related behavior is unclear, but genetic and environmental factors, such as pesticides, have been hypothesized. The objective of this study was to investigate the relationship between in utero exposure to chlorpyrifos, chlorpyrifos-methyl, and/or 3,5,6-trichloro-2-pyridinol (TCPY) and ADHD in school-age Mexican children using TCPY as a biomarker of exposure. The temporal reliability of repeated maternal urinary TCPY concentrations across trimesters was also explored (N=21). To explore associations with ADHD-related outcomes in children, third trimester urinary TCPY concentrations in were measured in 187 mother-child pairs from a prospective birth cohort. Child neurodevelopment in children 6-11 years of age was assessed using Conners' Parental Rating Scales-Revised (CRS-R), Conners' Continuous Performance Test (CPT), and Behavior Assessment System for Children-2 (BASC-2). Multivariable linear regression models were used to test relationships for all children combined and also stratified by sex. Intraclass correlation coefficients (ICC) calculations were based on a random effects model. The ICC was 0.41 for uncorrected TCPY, and ranged from 0.29 to 0.32 for specific gravity-corrected TCPY. We did not observe any statistically significant associations between tertiles of maternal TCPY concentrations and ADHD-related outcomes in children. However, compared to the lowest tertile we found suggestive evidence for increased ADHD index in the highest TCPY tertile in boys (ß=5.55 points; 95% CI (-0.19, 11.3); p=0.06) and increased attention problems for the middle tertile in girls (ß=5.81 points; 95% CI (-0.75, 12.4); p=0.08). Considering the continued widespread agricultural and possible residential use of chlorpyrifos and chlorpyrifos-methyl in Mexico and the educational implications of cognitive and behavior deficits, these relationships deserve further study.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/induzido quimicamente , Atenção/efeitos dos fármacos , Desenvolvimento Infantil/efeitos dos fármacos , Exposição Materna/efeitos adversos , Praguicidas/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal , Piridonas/efeitos adversos , Adulto , Agricultura , Criança , Comportamento Infantil/efeitos dos fármacos , Clorpirifos/efeitos adversos , Clorpirifos/análogos & derivados , Clorpirifos/urina , Feminino , Humanos , Masculino , México , Exposição Ocupacional/efeitos adversos , Praguicidas/urina , Gravidez , Terceiro Trimestre da Gravidez , Estudos Prospectivos , Piridonas/urina , Fatores Sexuais , Adulto Jovem
13.
Sci Total Environ ; 424: 351-5, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22425279

RESUMO

Thyroid hormones are vital to a host of human physiological functions in both children and adults. Exposures to chemicals, including chlorpyrifos, have been found to modify thyroid signaling at environmentally relevant levels in animal studies. The aim of this study was to examine circulating T4 and TSH levels in relation to urinary concentrations of 3, 5, 6-trichloro-2-pyridinol (TCPY), a metabolite of the organophosphorus insecticides chlorpyrifos and chlorpyrifos-methyl, using data from individuals 12 years and older from the U.S. National Health and Nutrition Examination Surveys (NHANES). NHANES datasets from 1999 to 2000 and 2001-2002 were combined, and individuals with thyroid disease, those taking thyroid medications, and pregnant women were excluded (N = 3249). Multivariable linear regression models for relationships between log-transformed urinary TCPY and serum total T(4) or log (TSH) were constructed adjusting for important covariates. Models were stratified by sex and a categorical age variable (12-18, 18-40, 40-60, and >60 years). In male participants, an interquartile range (IQR) increase in urinary TCPY was associated with statistically significant increases in serum T(4) of 3.8% (95th CI 0.75 to 7.0) among those 12-18 years of age and 3.5% (95th CI 0.13 to 7.0) in the 18-40 year age group, relative to median T4 levels using unweighted models. An IQR increase in TCPY was also associated with decreases in TSH of 10.7% (-18.7-2.05) among men 18-40 years old and 20.0% (95th CI -28.9 to -9.86) among men >60 years old. Conversely, urinary TCPY was positively associated with TSH in females >60 years of age. Further research to confirm these findings, elucidate mechanisms of action, and explore the clinical and public health significance of such alterations in thyroid hormones is needed.


Assuntos
Clorpirifos/análogos & derivados , Clorpirifos/toxicidade , Inseticidas/toxicidade , Piridonas/urina , Tireotropina/sangue , Tiroxina/sangue , Adolescente , Adulto , Idoso , Biomarcadores/urina , Clorpirifos/metabolismo , Feminino , Humanos , Técnicas Imunoenzimáticas , Inseticidas/metabolismo , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Extração em Fase Sólida , Estados Unidos , Adulto Jovem
14.
Artigo em Inglês | MEDLINE | ID: mdl-18172810

RESUMO

Increase in concentrations of various greenhouse gases and their possible contributions to the global warming are becoming a serious concern. Anthropogenic activities such as cultivation of flooded rice and application of waste materials, such as sewage sludge which are rich in C and N, as soil amendments could contribute to the increase in emission of greenhouse gases such as methane (CH(4)) and nitrous oxide (N(2)O) into the atmosphere. Therefore, evaluation of flux of various greenhouse gases from soils amended with sewage sludge is essential to quantify their release into the atmosphere. Two soils with contrasting properties (Candler fine sand [CFS] from Florida, and Ogeechee loamy sand [OLS] from Savannah, GA) were amended with varying rates (0, 24.7, 49.4, 98.8, and 148.3 Mg ha(-1)) of 2 types of sewage sludge (industrial [ISS] and domestic [DSS] origin. The amended soil samples were incubated in anaerobic condition at field capacity soil water content in static chamber (Qopak bottles). Gas samples were extracted immediately after amending soils and subsequently on a daily basis to evaluate the emission of CH(4), CO(2) and N(2)O. The results showed that emission rates and cumulative emission of all three gases increased with increasing rates of amendments. Cumulative emission of gases during 25-d incubation of soils amended with different types of sewage sludge decreased in the order: CO(2) > N(2)O > CH(4). The emission of gases was greater from the soils amended with DSS as compared to that with ISS. This may indicate the presence of either low C and N content or possible harmful chemicals in the ISS. The emission of gases was greater from the CFS as compared to that from the OLS. Furthermore, the results clearly depicted the inhibitory effect of acetylene in both soils by producing more N(2)O and CH(4) emission compared to the soils that did not receive acetylene at the rate of 1 mL g(-1) soil. Enumeration of microbial population by fluorescein diacetate (FDA) and most probable number (MPN) procedure at the end of 25-d incubation demonstrated a clear relationship between microbial activity and the emission of gases. The results of this study emphasize the need to consider the emission of greenhouse gases from soils amended with organic soil amendments such as sewage sludge, especially at high rates, and their potential contribution to global warming.


Assuntos
Poluentes Atmosféricos/análise , Ar , Gases/análise , Efeito Estufa , Esgotos/química , Solo/análise , Ar/análise , Ar/normas , Monitoramento Ambiental , Estados Unidos
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