Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "pollutant level" wg kryterium: Temat


Wyświetlanie 1-4 z 4
Tytuł:
Survey of polycyclic aromatic hydrocarbons and lead in Chinese teas sold in Nigeria: levels and health implications
Autorzy:
Orisakwe, O.E.
Mbagwu, H.O.C.
Ukpai, P.
Udowelle, N.A.
Tematy:
polycyclic aromatic hydrocarbon
lead
tea
Chinese tea
Nigeria
risk assessment
food safety
food analysis
pollutant level
health implication
Pokaż więcej
Wydawca:
Narodowy Instytut Zdrowia Publicznego. Państwowy Zakład Higieny
Powiązania:
https://bibliotekanauki.pl/articles/875164.pdf  Link otwiera się w nowym oknie
Opis:
Background. The belief that Chinese teas are of immense health benefits by many Nigerians has led to high consumption rate. Objectives. This study has determined lead and polycyclic aromatic hydrocarbons (PAHs) levels of Chinese teas popularly consumed in Nigeria and to estimate the potential health risks. Material and Methods. Twenty brands of Chinese teas commonly consumed in Nigeria purchased in October 2014 were used in the study. Tea samples were extracted and digested. Lead, and PAHs were analyzed using an atomic absorption spectrophotometric (AAS) and gas chromatographic methods, respectively. Daily intake, percent violations of permissible limits, target hazard quotients (THQ), Health Risk Index (HRI) of lead, and other cancer risk parameters of PAHs were estimated. Results. All the tea samples except super natural green tea violated the WHO permissible limit of lead (0.01 mg/kg) by over 100%. The HRI ranged from 5.09 x 10-5 – 7.20 x 10-4 . Among the single analyzed compounds, the pyrenes had the highest concentration of 14.31 mg/kg. The intake of benzo[a]pyrene was detected in 25% of the samples which ranged from 0.066 to 0.145 mg/kg and exceeded the permissible daily limit of benzo[a]pyrene intake. The estimated cancer risk from this study in an adult is 5.07 x 10-9. Conclusion. The present study suggests that consumption of Chinese teas in Nigeria may not be one of the factors responsible for the increased rate of cancer in Nigeria.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Pollution load assessment in the form of TSS and COD emitted from an urbanized catchment in the aspect of administrative pollutant discharge fees on the example of the activity of the J1 CSO in Lodz (Poland)
Autorzy:
Brzezińska, Agnieszka
Wiankowski, Lukasz
Tematy:
environmental engineering
CSO management
sewer system
weir crest level
environmental pollutant discharge fees
Pokaż więcej
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Powiązania:
https://bibliotekanauki.pl/articles/27310135.pdf  Link otwiera się w nowym oknie
Opis:
The article presents the possibility of reducing fees for wastewater discharge from combined sewer overflows (CSOs) into the aquatic environment by minimizing the load emission of total suspended solids (TSS) and chemical oxygen demand (COD). The analysis was conducted based on limiting the wastewater volume discharged to the receiving water by one of the viable options, i.e., raising the overflow crest. The assessment was made on the example of the functioning J1 CSO in Lodz (in Polish: Łódź) in the years 2013–2015. An analysis of rainfall recorded in the J1 catchment area was also performed for this period. For the determination of the TSS and COD load emitted to the receiver, a predictive model based on rainfall parameters and the volume of discharged wastewater was used. To determine the wastewater volume emitted during individual activations of the J1 overflow, the model of the sewer network serving this catchment was calibrated in the EPA SWMM software. Simulations were conducted, considering different heights of the weir crest (static change). The results of the analyzes showed that raising the crest by 5 cm reduced the total fee for the J1 activity by 35% compared to its existing height in 2013 and about 40% for 2015. Raising the crest by 10 cm in 2015 enabled, for example, the J1 overflow activity to be in accordance with the applicable law. Reducing the amount of wastewater discharged to the receiver by using the overflow crest height adjustment method presented in the article may bring measurable financial and ecological benefits.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ozone effects on trees, where uptake and detoxification meet
Autorzy:
De, Temmerman L
Vandermeiren, K.
D'Haese, D.
Bortier, K.
Asard, H.
Ceulemans, R.
Tematy:
air pollutant
ozone effect
oxidative defence
detoxification
ozone
critical level
tree
ozone concentration
effective ozone flux
Pokaż więcej
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Powiązania:
https://bibliotekanauki.pl/articles/41371.pdf  Link otwiera się w nowym oknie
Opis:
Ozone is the most important air pollutant and its concentration in ambient air is still rising. Ozone concentrations measured at reference height (50 m is EMEP ozone modelling height), do not reflect the real concentration at the top of the vegetative canopy and do not provide sufficient information about the ozone fluxentering the leaves. Modelling stomatal conductance is leading to estimations of cumulative ozone uptake and enables much better to evaluate the impact of ozone on trees. The negative impact of ozone exposure has a measurable effect on physiological processes such as stomatal conductance, photosynthesis and respiration. Disturbance of the basic physiological processes is leading to growth and wood production losses. There have been several attempts to establish critical levels (CL) for ozone effects on forest trees. Average concentrations and cumulative exposure indices are satisfactory to some extent, but do not fully describe the potential impact of ozone exposure. Much more promising is an evaluation based on the effective ozone flux, which is a function of the absorbed ozone flux and the defensive response. Ozone uptake takes place primarily through the stomata and reactions of ozone with hydrocarbons released by the plant cells and transformations of dissolved ozone in the apoplastic fluid create many reactive oxygen species of which free radicals are able to initiate membrane lipid peroxidation and destruction of cell membranes. The defence of a plant against absorbed ozone starts in the apoplastic fluid. Ascorbate is believed to be a very important radical scavenger avoiding detrimental effects of reactive oxygen species to the membranes. Other important antioxidants are phenolics. The defensive response can be linked to the abundance of ascorbate or the ability of the plants to regenerate (reduce) ascorbate from monodehydroascorbate and dehydroascorbate. The reduction of dehydroascorbate takes place in the symplast where ascorbate can be transported back through the plasma membrane into the apoplast. Ozone exposure also causes oxidative stress of the plant cell interior by the formation of reactive oxygen species. Plants can cope with those toxic substances in the symplast by using antioxidants such as ascorbate, -tocopherol, glutathione and carotenoids and enzymes such as superoxide dismutases, catalases and several peroxidases. The complexity of the apoplastic and symplastic antioxidative capacity with different turnover rates and transport of antioxidants makes it difficult to determine the total antioxidative power.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rozpoznanie stopnia skazenia chromem gleb i wod w okolicy skladowiska odpadow garbarskich k.Lubartowa [Polska]
The estimation of chrominum contamination degree of soil and water in the vicinity of tannery waste lagoon near Lubartow (Poland)
Autorzy:
Stepniewska, Z
Bucior, K.
Tematy:
Polska
Lubartow
gleby
skazenia gleby
skazenia wod
stopien skazenia
odpady przemyslowe
odpady garbarskie
skladowiska odpadow
metale ciezkie
chrom
Polska
Lubartow town
soil
soil pollutant
water pollutant
pollution level
industrial waste
tannery waste
waste landfill
heavy metal
chromium
Pokaż więcej
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Powiązania:
https://bibliotekanauki.pl/articles/1630455.pdf  Link otwiera się w nowym oknie
Opis:
Publikacja przedstawia skażenie gleby, wód i roślin przez chrom w okolicy składowiska odpadów garbarskich w Lubartowie. Przez ponad 20 lat odpady z garbarni zawierające duże ilości chromu były składowane w niezabezpieczonym wyrobisku piaskowym, które leży tuż przy rzece Wieprz. Wyniki naszych badań porównane są z wynikami raportów z początku lat 90 dotyczących skażenia chromem okolicy Lubartowa. Przedstawione jest porównanie dwóch metod określania stężenia chromu w glebie. Wyniki pokazują, że okolica składowiska odpadów jest wciąż skażona i wymaga poważnego programu oczyszczenia jej i przywrócenia do stanu przed składowaniem odpadów.
The article presents contamination of soil, water and plant with chrominum in the vicinity of tannery waste lagoon in Lubartow. reach in chrominum wastes from the tannery have been gathered for more than 20 years in usealed basin which was situated close to the Wieprz river.results of our investigations are compared with reports on chrominum contamination of the same object but coming from early nineties. Two methods of total chrominum determination in soils are compared. The results show that the area of waste disposal is still contaminated and a serious remediation program is needed.
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-4 z 4

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies