ABSTRACT
Air and surfaces in the hospital environment are a potential source of exposure to filamentous fungi (FF) that could cause invasive fungal diseases (IFD) in severely immunocompromised patients. The prevalent FF in IFD are species from the genera Aspergillus, Fusarium, Scedosporium, and those within the order Mucorales. We have compiled regulations and described the procedures used in the clinical mycology laboratory to assess the presence of FF in areas at risk for the development of IFD. The infection control committees of each establishment implement hospital policies to regulate and control processes aimed at preventing infections. Fungal load monitoring is an important step in this process to validate air quality in order to ensure a clean and protected environment for severely immunocompromised patients.
Subject(s)
Air Microbiology , Environmental Monitoring , Fungi , Humans , Air Microbiology/standards , Cross Infection/prevention & control , Cross Infection/microbiology , Environmental Monitoring/methods , Environmental Monitoring/standards , Fungi/isolation & purification , Health Facility Environment/organization & administration , Health Facility Environment/standards , Hospitals/standardsABSTRACT
Radiogenic strontium isotopes (87Sr/86Sr) have long been used in analyses of paleomobility within Mesoamerica. While considerable effort has been expended developing 87Sr/86Sr baseline values across the Maya region, work in central Mexico is primarily focused on the Classic period urban center of Teotihuacan. This study adds to this important dataset by presenting bioavailable 87Sr/86Sr values across central Mexico focusing on the Basin of Mexico. This study therefore serves to expand the utility of strontium isotopes across a wider geographic region. A total of 63 plant and water samples were collected from 13 central Mexican sites and analyzed for 87Sr/86Sr on a Thermo-Finnigan Neptune multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS). These data were analyzed alongside 16 published 87Sr/86Sr values from two additional sites within the region of interest. A five-cluster k-means model was then generated to determine which regions of the Basin of Mexico and greater central Mexico can and cannot be distinguished isotopically using 87Sr/86Sr values. Although the two clusters falling within the Basin of Mexico overlap in their local 87Sr/86Sr ranges, many locations within the Basin are distinguishable using 87Sr/86Sr values at the site-level. This study contributes to paleomobility studies within central Mexico by expanding knowledge of strontium isotope variability within the region, ultimately allowing researchers to detect intra-regional residential mobility and gain a greater understanding of the sociopolitical interactions between the Basin of Mexico and supporting outlying regions of central Mexico.
Subject(s)
Paleontology/methods , Strontium Isotopes/analysis , Strontium/analysis , Environmental Monitoring/methods , Environmental Monitoring/standards , Mexico , RadioisotopesABSTRACT
In ecotoxicological assays, previously selected and standardized organism tests are exposed to an environmental sample. Some species of the Chironomus genus have been extensively used in ecotoxicological assays. Among these, Chironomus tentans is usually utilized in the USA and Chironomus sancticaroli in Brazil. We conducted ecotoxicological bioassays to compare a population of C. sancticaroli, kept for 6 years under laboratory conditions, with a sylvatic population of the same species, collected in the field. The aim was to test the hypothesis that populations of C. sancticaroli, maintained in the laboratory for long periods, could have a different response to stressors/substances. We analyzed the responses of C. sancticaroli for potassium chloride, zinc chloride, potassium dichromate, linear alkylbenzene sulphonate (LAS) and caffeine. The results showed no significant differences between the two populations in the analyses and seems to indicate the possible use of C. sancticaroli from populations kept in the laboratory for long periods.
Subject(s)
Chironomidae/drug effects , Ecotoxicology/methods , Environmental Monitoring/methods , Water Pollutants, Chemical/toxicity , Animals , Biological Assay , Brazil , Chironomidae/growth & development , Ecotoxicology/standards , Environmental Monitoring/standards , Larva/drug effects , Larva/growth & developmentABSTRACT
The objective of this study was to evaluate the efficiency of Laser-Induced Breakdown Spectroscopy (LIBS) to detect the presence of bioaccumulated Fe and Pb in scales of Salminus brasiliensis and Prochilodus lineatus, and to compare the results from this technique with those obtained using the conventional atomic absorption spectrometry technique. The study used fish collected in the Amambai River, Upper Paraná River, Brazil. The LIBS technique detected the presence of Fe in S. brasiliensis scales and Fe and Pb in P. lineatus scales on different regions. Using atomic absorption spectrometry, we verified a significant difference in Fe concentration in scales between the species analyzed, with a higher concentration in S. brasiliensis than in P. lineatus (pâ¯=â¯0.0004). Pb was not detected using atomic absorption spectrometry in either species because the concentration of this element was below the limit of detection of this technique. The LIBS technique was efficient in detecting Fe and Pb in scales of the two species analyzed, proving to be a promising tool for environmental monitoring.
Subject(s)
Environmental Monitoring/methods , Fishes/metabolism , Lasers , Spectrophotometry, Atomic , Animals , Brazil , Environmental Monitoring/standards , Iron/analysis , Iron/pharmacokinetics , Lead/analysis , Lead/pharmacokinetics , Rivers/chemistryABSTRACT
Dioxins and furans are ubiquitous, anthropogenic environmental contaminants which can be found even in isolated places. Exposition to these chemicals poses several risks to humans such as thyroid dysfunction, cardiovascular diseases, and even cancer. In this review, the dioxin issue is analyzed in the light of the events that brought the World's attention to these pollutants, and the evolution of Brazilian scientific data on this matter since the citrus pulp crisis in 1998. Soil and air have been the main environmental matrices studied in Brazil. However, most of the research focuses on contaminated areas, with few or no data available on background levels. With the ratification of the Stockholm Convention in 2010, Brazil started to implement some measures to monitor the release of dioxins to the environment, such as the national inventory of sources. Still, the country lacks specific legislation stating acceptable limits for some industrial processes known to be source of dioxins emissions. Likewise, food monitoring has grown in recent years with the expansion of food groups monitored in the National Control Plan for Residues and Contaminants, but the available data do not allow affirming whether Brazilian residents are safe, as regard to exposure via food consumption. The implementation of a systemic survey such as a Total Diet Study would be a good strategy for a long-term monitoring not only for dioxins but also for other contaminants. Unfortunately, progressive cuts in science funds are holding back the scientific production in Brazil, whereas worldwide new emerging contaminants are being monitored and included in National Monitoring Plans both on food and environment matrices.
Subject(s)
Dioxins/chemistry , Environmental Monitoring/methods , Environmental Pollutants/chemistry , Environmental Pollution , Brazil , Citrus , Environmental Monitoring/standards , HumansABSTRACT
Introducción: Las organizaciones hospitalarias actuales deben trazarse como objetivo estratégico desarrollar un personal de alta competencia comprometido con la protección medioambiental, debido a la vital importancia de esta temática para lograr la supervivencia de la humanidad. Por tal motivo, las instituciones hospitalarias en Cuba, específicamente los hospitales Lucía Íñiguez Landín, Vlaimir Ilich Lenin y Octavio de la Concepción y la Pedraja, en el municipio de Holguín, presentan la necesidad de mejorar su desempeño ambiental a través de la formación de sus trabajadores, por ser factores claves en el logro del éxito organizacional. Objetivo: evaluar la eficacia de la integración de la dimensión ambiental en la formación de los recursos humanos en los hospitales en el municipio de Holguín. Métodos: Se emplearon los métodos teóricos histórico-lógico, analítico-sintético, inductivo-deductivo, sistémico-estructural y métodos estadísticos. Los métodos empíricos fueron encuestas a los trabajadores en los hospitales estudiados, entrevistas a los miembros el departamento de recursos humanos en los hospitales estudiados, observación participante y consulta de documentos para la recopilación de la información. Resultados: Con la aplicación de los métodos señalados en los hospitales Lucía Íñiguez Landín, Vladimir Ilich Lenin y Octavio de la Concepción de la Pedraja del municipio de Holguín, se obtuvo como resultados fundamentales la identificación y evaluación de los riesgos ambientales por puestos de trabajo, las competencias ambientales por cargos asociadas a los componentes, los procedimientos ambientales, la evaluación de la eficacia de la integración según los objetivos de la organización e individuales, así como mejoras en los indicadores de desempeño fundamentales(AU)
Introduction: The current hospital organizations should set a strategic goal to develop a highly competent staff committed to environmental protection, due to the vital importance of this issue to achieve the survival of humanity. Therefore, hospitals in Cuba, specifically Lucía Íñiguez Landín hospital, Vladimir Ilich Lenin hospital and Octavio de la Concepcion y la Pedraja hospital, in Holguin, show the need to improve their environmental performance through training their workers, for being key factors in achieving organizational success. Objective: To assess the efficacy of the integration of the environmental dimension in the training of human resources in these hospitals in the municipality of Holguín. Methods: Theoretical methods were used such as historical-logical, analytical-synthetic, inductive-deductive, systemic-structural and statistical. The empirical methods were surveys of workers in the hospitals studied, interviews with members, the human resources department in the hospitals studied, participant observation and consultation of documents for collecting information. Results: The study resulted in the identification and evaluation of environmental risks by job posts, environmental competencies by charges associated with the components, environmental procedures, and evaluation of the effectiveness of the integration according to the organization and individual objectives, as well as improvements in the fundamental performance indicators in these hospitals in Holguin(AU)
Subject(s)
Humans , Male , Female , Environmental Monitoring/standards , Hospitals , Environmental Health Education , CubaABSTRACT
Rodents used in biomedical research are maintained behind barriers to exclude microbial contaminants. Several check points have to be monitored to eliminate the potential of introducing adventitious agents into the facility. Microbiological monitoring of a mouse facility environment enables to evaluate the efficiency of sanitization and cleaning procedures, air quality, and technician good practices. At our SPF mouse facility, we implemented an environmental microbiological monitoring program based in sedimentation and swabbing, inexpensive and easy to use methods. The aim of this work was to evaluate the results and the efficiency of the monitoring program after seven years. The median for bacteria and fungi counts in the SPF sampled areas was ≤2 CFU/2 h for settle plates and <1 CFU per swabbing plate, satisfying the requirements for grade C of the EU-GMP, with some modifications. The environmental monitoring program was useful to detect early warning of problems and enabled us to define a safe range of microbiological counts. In addition, SPF status defined for our mice was maintained throughout this study, confirmed by our HM program. This work could encourage directors and technicians of other mouse facilities in Latin America and rest of the world to implement this kind of program.
Subject(s)
Animals, Laboratory/microbiology , Environmental Microbiology/standards , Environmental Monitoring/standards , Animals , Animals, Laboratory/parasitology , Animals, Laboratory/virology , Bacterial Load , Environment, Controlled , Facility Design and Construction , Female , Mice , Minute Virus of Mice , Program Evaluation/methods , Program Evaluation/standardsABSTRACT
In the tropical region, the greatest challenge of the biomonitoring approach is to establish linear relationships between biomarkers measured in plants and pollutant concentrations, since the bioindicator responses can be intensified or restricted by climatic variations. In southeastern Brazil, there are two regions affected by air pollution, where the Atlantic Forest remains and should be preserved. Consequently, both areas have been monitored by biomonitoring procedures using standardized and tropical plants. The industrial complex settled in Cubatão is one of the world's most famous examples of environmental pollution and degradation, with consequent decline of the Atlantic Forest. An oil refinery is among the most polluting industries in the Cubatão region. The other region is located in the Metropolitan Region of Campinas (MRC). The MRC has been affected by high levels of air pollutants originated from road traffic and is responsible for over 80% of CO, NOx, and hydrocarbon emissions and develops industrial activities that emit about 70% of the particulate matter present in the region. Both regions are distinguished by the climate, despite the fact that they are only about 130 km far from each other. Several studies carried out by our group in these regions aimed to establish the best native tree species and respective potential biomarkers for future assessment of pollution effects on tropical Forests. We present a critical review about the efficiency of native species compared to standardized bioindicator plants considering antioxidant defense system, nutrient accumulation, and microscopic aspects when exposed to atmospheric pollutants and climate.
Subject(s)
Air Pollutants/toxicity , Environmental Biomarkers/drug effects , Environmental Monitoring/methods , Environmental Monitoring/standards , Particulate Matter/toxicity , Trees/drug effects , Air Pollutants/analysis , Antioxidants/metabolism , Brazil , Forests , Particulate Matter/analysis , Tropical ClimateABSTRACT
Abstract The detection of pathogenic microorganisms in aquatic environments is extremely relevant in terms of public health. As these laboratorial methodologies are usually difficult, expensive and time-consuming, they are frequently replaced by the assessment of fecal indicator bacteria, such as Escherichia coli. This study aimed to assess the presence of E. coli in fecal samples from Neotropical otters, to evaluate its potential as fecal indicator to be applied to the determination of water microbiological quality in areas where otters' populations are high. Twenty-six otter fecal samples, collected in Alto Paranapanema river basin, São Paulo State, Brazil, were analyzed for the presence of E. coli, using conventional bacteriological methods. Only 8 scat samples (30%) were E. coli positive, indicating that this microorganism is not a suitable fecal indicator to assess water fecal contamination by Neotropical otters, and should not be used to infer the presence of otter related pathogens in waters.
Resumo A detecção de microrganismos patogênicos em ambientes aquáticos é extremamente importante em termos de saúde pública. Como estas metodologias laboratoriais são geralmente difíceis de realizar, dispendiosas e demoradas, são frequentemente substituídas pela avaliação de bactérias indicadoras de contaminação fecal, tais como Escherichia coli. Este estudo teve como objetivo avaliar a presença de E. coli em amostras fecais de lontras Neotropicais, para avaliar o seu potencial como indicador fecal e poder ser aplicado para a determinação da qualidade microbiológica da água em áreas onde as populações de lontras são numerosas. Vinte e seis amostras de fezes de lontra, coletadas na bacia do Alto Paranapanema, Estado de São Paulo, Brasil, foram analisadas quanto à presença de E. coli, utilizando métodos bacteriológicos convencionais. Apenas oito amostras de fezes (30%) se revelaram positivas para E. coli, indicando que este microrganismo não é um indicador fecal adequado para avaliar a contaminação fecal da água por lontras Neotropicais, e não deve ser usada para inferir a presença de agentes patogênicos relacionados com lontra em águas.
Subject(s)
Animals , Otters/microbiology , Water Pollution/analysis , Environmental Monitoring/standards , Rivers/microbiology , Escherichia coli/isolation & purification , Feces/microbiology , Water Quality , Environmental Monitoring/methodsABSTRACT
BACKGROUND: Mexico is included in the list of countries with concurrent arsenic and fluoride contamination in drinking water. Most of the studies have been carried out in the adult population and very few in the child population. Urinary arsenic and urinary fluoride levels have been accepted as good biomarkers of exposure dose. The Biomonitoring Equivalents (BE) values are useful tools for health assessment using human biomonitoring data in relation to the exposure guidance values, but BE information for children is limited. METHODS: We conducted a systematic review of the reported levels of arsenic and fluoride in drinking water, urinary quantification of speciated arsenic (inorganic arsenic and its methylated metabolites), and urinary fluoride levels in child populations. For BE values, urinary arsenic and fluoride concentrations reported in Mexican child populations were revised discussing the influence of factors such as diet, use of dental products, sex, and metabolism. RESULTS: Approximately 0.5 and 6 million Mexican children up to 14 years of age drink water with arsenic levels over 10 µg/L and fluoride over 1.5 mg/L, respectively. Moreover, 40% of localities with arsenic levels higher than 10 µg/L also present concurrent fluoride exposure higher than 1.5 mgF/L. BE values based in urinary arsenic of 15 µg/L and urinary fluoride of 1.2 mg/L for the environmentally exposed child population are suggested. CONCLUSIONS: An actual risk map of Mexican children exposed to high levels of arsenic, fluoride, and both arsenic and fluoride in drinking water was generated. Mexican normativity for maximum contaminant level for arsenic and fluoride in drinking water should be adjusted and enforced to preserve health. BE should be used in child populations to investigate exposure.
Subject(s)
Arsenic/urine , Drinking Water , Fluorides/urine , Water Quality/standards , Child , Drinking Water/adverse effects , Drinking Water/analysis , Drinking Water/chemistry , Environmental Exposure/adverse effects , Environmental Exposure/analysis , Environmental Exposure/prevention & control , Environmental Monitoring/methods , Environmental Monitoring/standards , Humans , Mexico/epidemiology , Risk Assessment , Water Pollutants, Chemical/urineABSTRACT
BACKGROUND: Toxic volatile organic compounds (VOC), like benzene, toluene, ethylbenzene and xylenes (BTEX), are atmospheric pollutants representing a threat to human health. They are released into the environment from mobile sources in urban settings, but newly polluted areas are gaining importance in countries where accelerated industrialization is taking place in suburban or rural settings. METHODS: The review includes studies done in Mexico and Latin-America and countries considered to have emerging economies and are compared with similar studies in developed countries. Data about environmental VOC levels and exposure of children have been included. Also, information about health effects was reviewed. Articles were searched in PubMed and Scopus, and information was also obtained from the United States Environmental Protection Agency (EPA), the EPAs Integrated Risk Information System (IRIS-EPA) and state reports on air quality of Mexican cities. RESULTS: VOC or BTEX levels reported in industrial and suburban areas were found to be higher due to the burning of fossil fuels and waste emission; whereas, in big cities, VOC emissions were mainly due to mobile sources. Even though TEX levels were under reference values, benzene was found at levels several times over this value in cities and even higher in industrial zones. Elevated VOC emissions were also reported in cities with industrial development in their peripheral rural areas.Public health relevance: Industrial activities have changed the way of life of small towns, which previously had no concern about environmental pollution and chemicals. No air monitoring is done in these places where toxic chemicals are released into rivers and the atmosphere. This work demonstrates the need for environmental monitors to protect human life in suburban and rural areas where industrial growth occurs without planning and ecological or health protection, compromising the health of new generations beginning in fetal development.
Subject(s)
Air Pollutants , Child Health , Environmental Monitoring , Volatile Organic Compounds , Child , Environmental Health/organization & administration , Environmental Monitoring/methods , Environmental Monitoring/standards , Humans , Latin America/epidemiologyABSTRACT
The detection of pathogenic microorganisms in aquatic environments is extremely relevant in terms of public health. As these laboratorial methodologies are usually difficult, expensive and time-consuming, they are frequently replaced by the assessment of fecal indicator bacteria, such as Escherichia coli. This study aimed to assess the presence of E. coli in fecal samples from Neotropical otters, to evaluate its potential as fecal indicator to be applied to the determination of water microbiological quality in areas where otters' populations are high. Twenty-six otter fecal samples, collected in Alto Paranapanema river basin, São Paulo State, Brazil, were analyzed for the presence of E. coli, using conventional bacteriological methods. Only 8 scat samples (30%) were E. coli positive, indicating that this microorganism is not a suitable fecal indicator to assess water fecal contamination by Neotropical otters, and should not be used to infer the presence of otter related pathogens in waters.
Subject(s)
Environmental Monitoring/standards , Escherichia coli/isolation & purification , Feces/microbiology , Otters/microbiology , Rivers/microbiology , Water Pollution/analysis , Animals , Environmental Monitoring/methods , Water QualityABSTRACT
Many organizations have suggested the use of the Calanoid copepod Acartia tonsa in protocols for acute toxicity tests. Nevertheless, these protocols present some problems, such as using 60-180µm meshes to separate specific stages of A. tonsa or carrying out the tests using small volumes that reflect high densities of A. tonsa that do not occur in nature, which could lead to distorted results. In addition, ecotoxicological studies may use statistical approaches that are inadequate for the type of data being analysed. For these reasons, some methodological approaches for bioassays using A. tonsa need to be clarified and revised. In this study, we present information about (i) the retention of copepodite stages of A. tonsa on 180, 330 and 500µm net meshes; (ii) tested storage volumes of 1 organism per 5, 10 or 20mL in each test container (TC); and (iii) considerations about the statistics employed. The results demonstrated that a net mesh of 180µm is capable of retaining all copepodite stages (CI to CVI), contrasting with the recommendation of using a 180µm mesh to separate out adults only. Coarser meshes (330 and 500µm) can also retain different proportions of all copepodite stages, but cannot separate out one developmental stage only. Twenty-five millilitres of medium in an open TC, commonly employed in bioassays simulating densities of 1 organism 5mL-1, completely evaporated, and the results showed that the TCs need to be covered (e.g., PVC film) and filled with a minimum of 100mL of culture medium (simulating densities of 1 organism 20mL-1) to avoid evaporation and increases in salinity. The current use of ANOVA in ecotoxicological studies with proportions of surviving organisms should also be reconsidered since the data are discrete and have a binomial distribution; general linear models (GLMs) are considered more adequate. The information presented here suggests some adjustments that hopefully will enable the improvement of the procedures and methods employed in studies of acute toxicity using the copepod A. tonsa.
Subject(s)
Biological Assay/methods , Copepoda/drug effects , Environmental Monitoring/methods , Toxicity Tests, Acute/methods , Water Pollutants, Chemical/toxicity , Animals , Biological Assay/standards , Brazil , Copepoda/growth & development , Ecotoxicology , Environmental Monitoring/standards , Salinity , Toxicity Tests, Acute/standardsABSTRACT
The exploitation and degradation of natural environments exert intense pressure on important ecosystems worldwide. Thus, it is necessary developing or adapting assessment methods to monitor environmental changes and to generate results to be applied to environmental management programs. The Brazilian Veredas (phytophysiognomies typical to the Cerrado biome) are threatened by several human activities; thus, the aim of the present study is to adapt a rapid assessment protocol (RAP) to be applied to Veredas springs, by using the upper course of the Vai-e-Vem stream watershed (Ipameri County, Goiás State, Brazil). Therefore, several springs in the study site were visited and 11 of them were considered Veredas springs. After the RAP was adapted, the instrument was validated and used to environmentally assess the springs in order to demonstrate its applicability. The present study has provided an instrument of option to monitor Veredas springs.
Subject(s)
Environmental Monitoring/methods , Natural Springs , Wetlands , Brazil , Ecosystem , Environment , Environmental Monitoring/standardsABSTRACT
Coastal wetland responses to sea-level rise are greatly influenced by biogeomorphic processes that affect wetland surface elevation. Small changes in elevation relative to sea level can lead to comparatively large changes in ecosystem structure, function, and stability. The surface elevation table-marker horizon (SET-MH) approach is being used globally to quantify the relative contributions of processes affecting wetland elevation change. Historically, SET-MH measurements have been obtained at local scales to address site-specific research questions. However, in the face of accelerated sea-level rise, there is an increasing need for elevation change network data that can be incorporated into regional ecological models and vulnerability assessments. In particular, there is a need for long-term, high-temporal resolution data that are strategically distributed across ecologically-relevant abiotic gradients. Here, we quantify the distribution of SET-MH stations along the northern Gulf of Mexico coast (USA) across political boundaries (states), wetland habitats, and ecologically-relevant abiotic gradients (i.e., gradients in temperature, precipitation, elevation, and relative sea-level rise). Our analyses identify areas with high SET-MH station densities as well as areas with notable gaps. Salt marshes, intermediate elevations, and colder areas with high rainfall have a high number of stations, while salt flat ecosystems, certain elevation zones, the mangrove-marsh ecotone, and hypersaline coastal areas with low rainfall have fewer stations. Due to rapid rates of wetland loss and relative sea-level rise, the state of Louisiana has the most extensive SET-MH station network in the region, and we provide several recent examples where data from Louisiana's network have been used to assess and compare wetland vulnerability to sea-level rise. Our findings represent the first attempt to examine spatial gaps in SET-MH coverage across abiotic gradients. Our analyses can be used to transform a broadly disseminated and unplanned collection of SET-MH stations into a coordinated and strategic regional network. This regional network would provide data for predicting and preparing for the responses of coastal wetlands to accelerated sea-level rise and other aspects of global change.
Subject(s)
Climate Change , Ecosystem , Environmental Monitoring/standards , Seawater , Wetlands , Alabama , Environmental Monitoring/methods , Florida , Gulf of Mexico , Information Services/organization & administration , Information Services/standards , Louisiana , Mississippi , Research Design/standards , Sampling Studies , TexasABSTRACT
References areas are sites that have undergone little or no anthropogenic impact and therefore represent the natural state of an environment. The objective of this study was to test if the Camamu Bay (CB), Bahia, can be used as a reference area for tropical coastal environments. Trace and major elements, polycyclic aromatic hydrocarbons (PAH), and the structure of the benthic macrofauna were determined. To compare the studied sites and identify the possible occurrence of anomalous concentrations, trace elements were normalized by Al and linear regressions were also performed. For all trace elements (except Cu), regressions showed a significant correlation (p<0.05) and few outliers (<3% of cases), showing that the concentrations found represent natural values for this bay. In the case of Cu, the highest concentrations were found near small municipalities, which may be associated with domestic sewage. About 60% of the organic compounds occurred at levels below the limit of quantification (<0.26ngg-1). The sum of PAHs was low for all stations, ranging from 1.17 to 313ngg-1. The benthic assemblages also indicated that the CB is a healthy, well-preserved ecosystem that deserves conservation efforts. The integrated use of geochemical and biotic data supported the use of CB as a reference area. Capsule: Organic and inorganic contaminants together with macrobenthic assemblages indicated that Camamu Bay is a pristine, tropical reference area.
Subject(s)
Environmental Monitoring/standards , Water Pollutants, Chemical/analysis , Animals , Aquatic Organisms , Bays , Brazil , Ecosystem , Environmental Monitoring/methods , Metals/analysis , Organic Chemicals/analysis , Polycyclic Aromatic Hydrocarbons/analysis , Sewage , Tropical ClimateABSTRACT
Pollution levels have been increasing in water ecosystems worldwide. A water quality index (WQI) is an available tool to approximate the quality of water and facilitate the work of decision-makers by grouping and analyzing numerous parameters with a single numerical classification system. The objective of this study was to develop a WQI for a dam used for irrigation of about 5000 ha of agricultural land. The dam, La Vega, is located in Teuchitlan, Jalisco, Mexico. Seven sites were selected for water sampling and samples were collected in March, June, July, September, and December 2014 in an initial effort to develop a WQI for the dam. The WQI methodology, which was recommended by the Mexican National Water Commission (CNA), was used. The parameters employed to calculate the WQI were pH, electrical conductivity (EC), dissolved oxygen (DO), total dissolved solids (TDS), total hardness (TH), alkalinity (Alk), total phosphorous (TP), Cl-, NO3, SO4, Ca, Mg, K, B, As, Cu, and Zn. No significant differences in WQI values were found among the seven sampling sites along the dam. However, seasonal differences in WQI were noted. In March and June, water quality was categorized as poor. By July and September, water quality was classified as medium to good. Quality then decreased, and by December water quality was classified as medium to poor. In conclusion, water treatment must be applied before waters from La Vega dam reservoir can be used for irrigation or other purposes. It is recommended that the water quality at La Vega dam is continually monitored for several years in order to confirm the findings of this short-term study.