scholarly journals Dietary tissue cadmium accumulation in an amazonian teleost (Tambaqui, Colossoma macropomum Cuvier, 1818)

2007 ◽  
Vol 67 (4) ◽  
pp. 657-661 ◽  
Author(s):  
AYO. Matsuo ◽  
AL. Val
Keyword(s):  
Amazon Basin ◽  
Graphite Furnace ◽  
Primary Source ◽  
Cadmium Accumulation ◽  
Atomic Absorption Spectrophotometry ◽  
Colossoma Macropomum ◽  
Feeding Trials ◽  
Dry Food ◽  
Dietary Cadmium ◽  
The City

Understanding the effects of metal contamination in the Amazon basin is important because of the potential impact on this region of high biodiversity. In addition, the significance of fish as the primary source of protein for the local human population (living either alongside the Amazon River or in the city of Manaus) highlights the need for information on the metal transfer through the food chain. Bioaccumulation of metals in fish can occur at significant rates through the dietary route, without necessarily resulting in death of the organism. The goal of this work was to expose an economic relevant species from the Amazon basin (tambaqui, Colossoma macropomum) to dietary cadmium (Cd) at concentrations of 0, 50, 100, 200, and 400 µg.g-1 dry food. Fish were sampled on days 15, 30, and 45 of the feeding trials. Tissues were collected for analysis of Cd concentration using graphite furnace atomic absorption spectrophotometry. Cd accumulation in the tissues occurred in the following order: kidney > liver > gills > muscle. Relative to other freshwater fish (e.g., rainbow trout, tilapia), tambaqui accumulated remarkably high levels of Cd in their tissues. Although Cd is known to affect Ca2+ homeostasis, no mortality or growth impairment occurred during feeding trials.

scholarly journals Effects of the COVID-19 Lockdown on Urban Light Emissions: Ground and Satellite Comparison

2021 ◽  
Vol 13 (2) ◽  
pp. 258
Author(s):  
Máximo Bustamante-Calabria ◽  
Alejandro Sánchez de Miguel ◽  
Susana Martín-Ruiz ◽  
Jose-Luis Ortiz ◽  
José M. Vílchez ◽  
...  
Keyword(s):  
Economic Activity ◽  
Primary Source ◽  
Clear Correlation ◽  
Light Pollution ◽  
Nocturnal Activity ◽  
Empirical Expression ◽  
Anthropogenic Aerosol ◽  
The Earth ◽  
Sky Brightness ◽  
The City

‘Lockdown’ periods in response to COVID-19 have provided a unique opportunity to study the impacts of economic activity on environmental pollution (e.g., NO2, aerosols, noise, light). The effects on NO2 and aerosols have been very noticeable and readily demonstrated, but that on light pollution has proven challenging to determine. The main reason for this difficulty is that the primary source of nighttime satellite imagery of the earth is the SNPP-VIIRS/DNB instrument, which acquires data late at night after most human nocturnal activity has already occurred and much associated lighting has been turned off. Here, to analyze the effect of lockdown on urban light emissions, we use ground and satellite data for Granada, Spain, during the COVID-19 induced confinement of the city’s population from 14 March until 31 May 2020. We find a clear decrease in light pollution due both to a decrease in light emissions from the city and to a decrease in anthropogenic aerosol content in the atmosphere which resulted in less light being scattered. A clear correlation between the abundance of PM10 particles and sky brightness is observed, such that the more polluted the atmosphere the brighter the urban night sky. An empirical expression is determined that relates PM10 particle abundance and sky brightness at three different wavelength bands.

scholarly journals Dietary Cadmium Intake and Sources in the US

Nutrients ◽  
2018 ◽  
Vol 11 (1) ◽  
pp. 2 ◽  
Author(s):  
Kijoon Kim ◽  
Melissa Melough ◽  
Terrence Vance ◽  
Hwayoung Noh ◽  
Sung Koo ◽  
...  
Keyword(s):  
Body Weight ◽  
Primary Source ◽  
Leafy Vegetables ◽  
Food Sources ◽  
Food Groups ◽  
Toxic Heavy Metal ◽  
Tolerable Weekly Intake ◽  
The Us ◽  
Dietary Cadmium ◽  
Cd Exposure

Cadmium (Cd) is a toxic heavy metal that can contribute to numerous diseases as well as increased mortality. Diet is the primary source of Cd exposure for most individuals, yet little is known about the foods and food groups that contribute most substantially to dietary Cd intake in the US. Therefore, the objective of this study was to estimate dietary Cd intake and identify major food sources of Cd in the US population and among subgroups of the population. Individuals aged 2 years and older from the National Health and Nutrition Examination Survey (NHANES) 2007–2012 were included in this study (n = 12,523). Cd intakes were estimated from two days of 24-h dietary recalls by matching intake data with the Cd database of the Food and Drug Administration (FDA)’s Total Diet Study 2006 through 2013. The average dietary Cd consumption in the population was 4.63 μg/day, or 0.54 μg/kg body weight/week, which is 22% of the tolerable weekly intake (TWI) of 2.5 μg/kg body weight/week. Greater daily Cd intakes were observed in older adults, males, those with higher income, higher education, or higher body mass index. The highest Cd intakes on a body weight basis were observed in children 10 years and younger (38% of TWI), underweight individuals (38% of TWI), and alcohol non-consumers (24% of TWI). The food groups that contributed most to Cd intake were cereals and bread (34%), leafy vegetables (20%), potatoes (11%), legumes and nuts (7%), and stem/root vegetables (6%). The foods that contributed most to total Cd intake were lettuce (14%), spaghetti (8%), bread (7%), and potatoes (6%). Lettuce was the major Cd source for Caucasians and Blacks, whereas tortillas were the top source for Hispanics, and rice was the top contributor among other ethnic subgroups including Asians. This study provides important information on the dietary Cd exposure of Americans, and identifies the groups with the greatest dietary Cd exposure as well as the major sources of dietary Cd among sociodemographic subgroups.

scholarly journals Genetic variation in native and farmed populations of Tambaqui (Colossoma macropomum) in the Brazilian Amazon: regional discrepancies in farming systems

2013 ◽  
Vol 85 (4) ◽  
pp. 1439-1447 ◽  
Author(s):  
Jonas Aguiar ◽  
Horacio Schneider ◽  
Fatima Gomes ◽  
Jeferson Carneiro ◽  
Simoni Santos ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Dna Sequences ◽  
Amazon Basin ◽  
Farming Systems ◽  
Wild Populations ◽  
The West ◽  
Colossoma Macropomum ◽  
Breeding Stock ◽  
History Of

The tambaqui, Colossoma macropomum, is the most popular fish species used for aquaculture in Brazil but there is no study comparing genetic variation among native and farmed populations of this species. In the present study, we analyzed DNA sequences of the mitochondrial DNA to evaluate the genetic diversity among two wild populations, a fry-producing breeding stock, and a sample of fish farm stocks, all from the region of Santarém, in the west of the Brazilian state of Pará. Similar levels of genetic diversity were found in all the samples and surprisingly the breeding stock showed expressive representation of the genetic diversity registered on wild populations. These results contrast considerably with those of the previous study of farmed stocks in the states of Amapá, Pará, Piauí, and Rondônia, which recorded only two haplotypes, indicating a long history of endogamy in the breeding stocks used to produce fry. The results of the two studies show two distinct scenarios of tambaqui farming in the Amazon basin, which must be better evaluated in order to guarantee the successful expansion of this activity in the region, and the rest of Brazil, given that the tambaqui and its hybrids are now farmed throughout the country.

scholarly journals The Glaciochemistry of Snow-Pits from Quelccaya Ice Cap, Peru, 1982

1985 ◽  
Vol 7 ◽  
pp. 84-88 ◽  
Author(s):  
W. Berry Lyons ◽  
A. Paul Mayewski ◽  
Lonnie G. Thompson ◽  
Boyd Allen
Keyword(s):  
Amazon Basin ◽  
Atomic Absorption Spectrophotometry ◽  
High Elevation ◽  
Common Source ◽  
Gaseous Emissions ◽  
Polar Ice ◽  
Peruvian Andes ◽  
Reactive Iron ◽  
Ice Cap ◽  
Quelccaya Ice Cap

We present glaciochemical data from a pilot study of two snow-pits from Quelccaya ice cap, Peruvian Andes. These are the first samples to be analyzed from Quelccaya for nitrate and sulfate by ion chromatography (IC), for nitrate-plus-nitrite, reactive silicate and reactive iron by colorimetry, and for sodium by atomic absorption spectrophotometry. The 3 m pits used in this study represent a one year record of mass accumulation and the 29 samples collected provide the first glaciochemical data from this area which can be compared with glaciochemical studies from other locations.Reactive iron, reactive silicate and sodium, and the profiles of >0.63μm microparticles from Thompson and others (1984) are coincident, suggesting that transport and deposition into this area of each species are controlled by similar processes. The common source is probably local, resulting from crustal weathering. In general, the reactive silicate values are lower than those observed in other alpine glacier ice. The highest sulfate and nitrate values were observed in the upper few centimeters of the snow-pit. Most of the sulfate concentrations were less than 3 μM and are similar to values obtained for fresh surface snows from Bolivia (Stallard and Edmond 1981). Since biological gaseous emissions are thought to be the major source of sulfur and nitrogen to the atmosphere over the Amazon basin, the sulfate and nitrate fluctuations may be due to seasonal biological input and/or seasonal shifts in wind direction bringing material to Quelccaya.With only one exception, the colorimetric nitrate-plus-nitrite data were higher than the IC nitrate data. Unfortunately, the IC analyses were conducted 81 d after the colorimetric analyses. The difference between the two data sets could be attributable to the following: (1) the colorimetric technique may yield erroneously high results as suggested for polar ice by Herron (1982), (2) the IC technique yields erroneously low results due, in part, to the possible exclusion of nitrite concentrations, and/or (3) nitrite was lost via biological removal during the 81 d period before the IC analyses. If the IC data are correct, the mean nitrate value is 0.4μΜ (n = 29). This value is similar to those reported from pre-industrial aged polar ice (Herron 1982). If the colorimetric mean value (1.1 μM) is correct, it is similar to colorimetrically determined values from other high-elevation alpine ice (Lyons and Mayewski 1983).

scholarly journals Ecological Quality of Natural Waters from of Kharkiv Urban Springs

2019 ◽  
Keyword(s):  
Water Samples ◽  
Natural Waters ◽  
Electrical Potential ◽  
Field Research ◽  
Water Hardness ◽  
Atomic Absorption Spectrophotometry ◽  
Nitrate Content ◽  
Pollutant Concentrations ◽  
Rigidity Index ◽  
The City

Purpose. Estimation of ecological safety of spring waters of the city of Kharkiv. Methods. Field research, atomic absorption spectrophotometry, analytical methods for studying water quality indicators. Results. Natural water samples were analyzed on the following parameters: pH, electrical potential, nitrate content, chlorides, ammonia, transparency, turbidity, and water hardness. The highest values of the content of nitrates, nitrites, as well as the level of alkalinity and rigidity were found in a sample from the Kholodnogorsk spring. In the water from the Zhukovsky spring the high content of chlorides is found, which is one and a half times higher than the concentration in water from other city springs. In the water from the Glyboky Yar spring the lowest mineralization of water was detected, and in the water from the Sarzhin Yar spring - the highest of the studied samples of water from the natural springs of Kharkiv. However, all identified pollutant concentrations except for the rigidity index is not dangerous for a person, because they are not exceeded by the MAC. The results of research on water samples from the Sarzhin Yar spring and from the spring in Yunost park (Kholodnogorsk source) in 2019, compared to the results of a similar study conducted in 2015. It was determined that in the water from the Sarzhin Yar spring the rigidity index increased 3.4 times, and in the sample from the spring in Yunost park (Kholodnogorsk spring) almost 6 times. Conclusions. It is determined that in the territory of the city of Kharkiv, water from the Zhukovskii spring in the Kyivskiy district is fully suitable for consumption, because its chemical composition is fully in line with the sanitary norms that apply to drinking spring waters. The value of the level of hardness of water in all samples, except Zhukovsky spring, indicate that the normative value exceeds 2-3 times. The rigidity of drinking water that exceeds the MAC may adversely affect human health. Therefore, the only ecologically safe, among the investigated, can be considered water from the Zhukovsky spring (Kievskiy district in Kharkiv). For other sources, it is recommended to modernize the water collection sites for the population, reconstruct the system of water supply for the supply of water from these sources, as well as to introduce additional stages of their treatment on the way to the consumer.

Evidence that the mechanisms of fungitoxicity of 8-quinolinol and its bischelate with copper(II) are different

1985 ◽  
Vol 31 (8) ◽  
pp. 707-710 ◽  
Author(s):  
Herman Gershon ◽  
Anthony T. Grefig ◽  
David J. Cady
Keyword(s):  
Minimal Inhibitory Concentration ◽  
Inhibitory Concentration ◽  
Graphite Furnace ◽  
Trichoderma Viride ◽  
Atomic Absorption Spectrophotometry ◽  
Test System ◽  
Growth Media ◽  
Minimal Inhibitory Concentrations ◽  
Absorption Spectrophotometry ◽  
Inhibition Of Growth

The copper(II) contents of the growth media, Sabouraud dextrose and Czapek–Dox broths, and of the spore inocula of Aspergillus niger (ATCC 1004), Aspergillus oryzae (ATCC 1011), Trichoderma viride (ATCC 8678), and Myrothecium verrucaria (ATCC 9095) were determined by atomic absorption spectrophotometry in a graphite furnace. The test systems composed of Sabouraud dextrose broth and spore inocula of the four fungi contained only a little over 3% of the copper(II) required to form a minimal inhibitory concentration of bis(8-quinolinolato)copper(II). The test system of Czapek–Dox broth and A. oryzae contained slightly less than 65% of the copper(II) required to form a minimal inhibitory concentration of the bischelate of 8-quinolinol with copper(II). When the minimal inhibitory concentrations of 8-quinolinol and bis(8-quinolinolato)copper(II) were added simultaneously to the test system of Czapek–Dox broth and A. oryzae, 10% of the combined mixture of toxicants caused complete inhibition of growth indicating synergism between the toxicants. These results together with the observation that α-lipoic acid as well as small aliphatic thiol-containing compounds (cysteine, glutathione, dithioerythritol, and dithiothreitol) reversed the toxicity of 8-quinolinol but not the toxicity of bis(8-quinolinolato)copper(II) led to the conclusion that the mechanisms of fungitoxicity of both toxicants are different.

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