scholarly journals Absorption of Hazardous Pollutants by a Medicinal FernBlechnum orientaleL.

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Xiao-min Zhu ◽  
Yuan-wen Kuang ◽  
Dan Xi ◽  
Jiong Li ◽  
Fa-guo Wang

A Chinese medicinal fernBlechnum orientale(Linn) was separately collected from polluted and unpolluted sites to determine whether it could accumulate hazardous pollutants or not. Metal concentrations (Cu, Zn, Mn, Pb, Cd, Cr, As, and Hg) both in the fronds and roots and polycyclic aromatic hydrocarbons (PAHs) in the fronds of this fern were quantified. At both sites, roots ofB. orientalehad significantly higher heavy metals than the fronds. Concentrations of Pb, As, Hg, Cd, and Cu in the fronds at the polluted site were more than 2, 6, 7, 14, 5, and 13 times of those at the unpolluted site. Translocation factor and bioaccumulation factor implied thatB. orientaledid not have a good ability to transport heavy metals from the roots to the fronds. Total PAHs in the fronds at the polluted site were significantly higher than those at the unpolluted site, indicating the physiological PAHs absorption byB. orientalegrowing at polluted sites. Uptake of pollutants via stomata might be the main reason causing the significant accumulation of hazardous pollutants in the fronds ofB. orientale. Large-scale systematical survey and intensive monitoring on pollutants in this medicinal fern should be necessarily strengthened.

2021 ◽  
Author(s):  
Kristen Kieta ◽  
Philip Owens ◽  
Ellen Petticrew

<p>The Nechako River Basin (NRB) in central British Columbia is a large (52,000 km<sup>2</sup>), regulated basin that supports populations of sockeye and chinook salmon and the endangered Nechako white sturgeon. These important species are experiencing population declines and one potential cause of this decline is excess sediment, which can clog their spawning habitat and reduce juvenile success. This excess sediment is likely the product of a combination of factors, the most visible being the significant land cover changes that have occurred in the basin, which includes pressure from forestry and agriculture, the Mountain Pine Beetle epidemic, and large-scale wildfires in 2018. Focusing specifically on the impact of the 2018 wildfires on sediment transport from upland burned areas to adjacent waterways, this research aimed to determine the spatial and temporal contamination of tributaries and the mainstem of the Nechako River with polycyclic aromatic hydrocarbons (PAHs), which are produced during the combustion of organic matter and have been identified as toxic to aquatic organisms and to humans. Additionally, this study intended to determine if burned areas were a more significant contributor of sediment than unburned areas and better understand the utility of PAHs as a potential tracer. Source soil samples were collected in 2018 and 2020 from burned and unburned sites, and suspended sediment samples were collected throughout the ice-free period from 2018-2020 in three tributaries and three mainstem sites. All samples were analysed for PAHs, magnetic susceptibility, colour, and particle size. Results from the fall 2018 source samples show a significant difference in PAH concentrations between unburned and burned soils, and while concentrations of PAHs in source soils in 2020 were lower than in 2018, they were still elevated compared to unburned soils. Sediment samples showed that concentrations of total PAHs are higher in the mainstem sites than in the tributaries, with the greatest concentrations consistently found at the most downstream site on the mainstem of the Nechako River. Concentrations across sites were highest in samples taken during the spring snowmelt period in 2019, have decreased throughout the rest of the sampling period (2019-2020), and are well below sediment quality guidelines for total PAHs. In addition to determining the spatial and temporal extent of PAH contamination, this study also aims to use PAHs along with colour and measurements of magnetic susceptibility to trace sediments associated with the 2018 wildfires. The high cost of PAH analysis limits the number of samples that can be analysed and thus, these additional tracers will allow for the use of models such as MixSIAR that improve with a more robust number of samples. As large-scale megafires continue to burn across the globe, understanding their potential to contribute PAHs to local waterbodies and potentially be used as a tracer is as prescient as ever.</p>


2021 ◽  
Vol 83 (5) ◽  
pp. 1017-1027
Author(s):  
Tingting Zang ◽  
Haizhen Wu ◽  
Yuxiu Zhang ◽  
Chaohai Wei

Abstract The polycyclic aromatic hydrocarbons (PAHs) that accumulate during the coking wastewater treatment process are hazardous for the surrounding environment. High molecular weight (HMW) PAHs account for more than 85% of the total PAHs in coking wastewater and sludge, respectively. The degradation of total PAHs increased by 18.97% due to the increased bioavailability of PAHs, after the biosurfactant-producing bacteria Pseudomonas aeruginosa S5 was added. The toxicity of total PAHs to humans was reduced by 26.66% after inoculation with S5. The results suggest biosurfactant-producing bacteria Pseudomonas aeruginosa S5 not only increase the biodegradation of PAHs significantly, but also have a better effect on reducing the human toxicity of PAHs. Kinetic analyses show that PAHs biodegradation fits to first-order kinetics. The degradation rate constant (k) value decreases as the number of PAH rings increases, indicating that HMW PAHs are more difficult to be biodegraded than low molecular weight (LMW) PAHs. The results indicate the bioaugmentation with the biosurfactant-producing strain has significant potential and utility in remediation of PAHs-polluted sites.


2019 ◽  
Vol 6 (13) ◽  
pp. 401-411
Author(s):  
Bridget Odiyi ◽  
Foluso Akinbode Ologundudu ◽  
Tobi Adegbite

Toxicity of heavy metals above the normal threshold constituted a threat to humanity and biodiversity. Phytoremediation has become a novel and emerging technology of cleaning polluted sites through the use of plants. A study was carried out at the screen house located besides the academic building of the Federal University of Technology, Akure, Nigeria, to evaluate the phytoremediation potential of Amaranthus hybridus L. (Caryophyllales: Amaranthaceae) on a brewery effluent. The parameters investigated include chlorophyll content, the concentration of the metals in the plants, Bioconcentration Factor (BCF) and Translocation Factor (TF) was studied. Three different concentrations of brewery effluent were used at 50, 100 and 150 mL/5 kg of soil, respectively. The results of this study under controlled conditions indicate that effluent application increased chlorophyll content, reduced plant height and stem girth. Three heavy metals (iron, cadmium, and chromium) were detected in the shoots and leave of both plants after the experimental period. The translocation factor (less than 1) and bioaccumulation factors (greater than 1) were below the permissible limits hence indicating a possible bio-accumulator for the heavy metals investigated. Brewery effluent reduce the plant height but increase the leaf area of A. hybridus under high concentrations which possibly suggest an adaptive mechanism developed by the plant under stress.


Author(s):  
Iqra Azam ◽  
Bakhtawar Sajjad ◽  
Hina Sarwar ◽  
Aleeza Javeed ◽  
Anam Riaz ◽  
...  

In the present study, concentration effects of different heavy metals (Pb and Mg) in Rosa indica are observed to detect the changes in growth response due to effect of metal’s toxicity. Both metals have different tolerance index. Lead is toxic metal and has small tolerance index, whereas Mg is a macronutrient having a high tolerance index which can move in a large scale to different parts of the plants. The least and highest accumulation values of Pb and Mg were observed as 0.608-25.897 mg/L and 20948-52291 mg/L, respectively. The toxicity order in rose plant is Pb>Mg. The bio concentration and translocation factor values of Pb and Mg were 0.97, 0.77, 0.93 and 0.9 respectively. In lead polluted soil, plants height shown is declined due to the concentration of lead (66.38 cm-56.48 cm) whereas plant height increased because of massive concentrations of Mg (63.93 cm-75.03 cm). Results `revealed that accumulation of both metals were excessive in the roots and least in the stem and leaves. It is concluded that rose plant is a good accumulator of lead and magnesium.


Plants ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1057
Author(s):  
Ehab Azab ◽  
Ahmad K. Hegazy

Heavy metal-contaminated soil constitutes many environmental concerns. The toxic nature of heavy metals poses serious threats to human health and the ecosystem. Decontamination of the polluted soil by phytoremediation is of fundamental importance. Vegetation is an appealing and cost-effective green technology for the large-scale phytoremediation of polluted soils. In this paper, a greenhouse experiment was carried out to test the potential of Rhazya stricta as a heavy metal phytoremediator in polluted soil. Plants were grown for three months in pots filled with soils treated with the heavy metals Cd, Pb, Cu, and Zn at rates of 10, 50, and 100 mg/kg. The bioaccumulation factor (BCF) and translocation factor (TF) were calculated to detect the ability of R. stricta to accumulate and transfer heavy metals from soil to plant organs. The results showed that under increasing levels of soil pollution, the bioconcentration of Cd and Zn heavy metals showed the highest values in plant roots followed by leaves, whereas in the case of Pb and Cu, roots showed the highest values followed by stems. Heavy metals accumulation was higher in roots than in stems and leaves. The BCF of Zn reached the highest values in roots and stems for 10 mg/kg soil treatment, followed by the BCFs of Cd, Cu, and Pb. The TF for the different heavy metal pollutants’ concentrations was less than unity, suggesting that the plants remediate pollutants by phytostabilization. The TF values ranged from higher to lower were in the order Zn > Cu > Cd > Pb. The rapid growth of R. stricta and its tolerance of heavy metals, as well as its ability to absorb and accumulate metals within the plant, recommends its use in the phytoremediation of slightly polluted soils in arid lands by limiting the heavy metals transport.


2021 ◽  
Vol 13 (14) ◽  
pp. 7652
Author(s):  
Giuseppe Cavallo ◽  
Chiara Lorini ◽  
Giuseppe Garamella ◽  
Guglielmo Bonaccorsi

Moderate or severe food insecurity affect 2 billion people worldwide. The four pillars of food security (availability, access, use and stability) are in danger due to the impact of climatic and anthropogenic factors which impact on the food system. Novel foods, like seaweeds, have the potential to increase food yields so that to contribute in preventing or avoiding future global food shortages. The purpose of this systematic review was to assess microbiological, chemical, physical, and allergenic risks associated with seaweed consumption. Four research strings have been used to search for these risks. Preferred Reporting Item for Systematic Reviews and Meta-analysis (PRISMA) guidelines were applied. Finally, 39 articles met the selected criteria. No significant hazards for microbiological, allergenic, and physical risks were detected. Regarding chemical risk, algae can accumulate various heavy metals, especially when harvested in polluted sites. Cultivating seaweeds in a controlled environment allows to avoid this risk. Periodic checks will be necessary on the finished products to monitor heavy metals levels. Since the consumption of algae seems to be on the rise everywhere, it seems to be urgent that food control authorities establish the safety levels to which eating algae does not represent any risk for human health.


2021 ◽  
Vol 13 (8) ◽  
pp. 4405
Author(s):  
Miroslav Rimar ◽  
Olha Kulikova ◽  
Andrii Kulikov ◽  
Marcel Fedak

Waste is a product of society and one of the biggest challenges for future generations is to understand how to sustainably dispose of large amounts of waste. The main objective of this study was to determine the possibility and conditions of the decentralized combustion of non-hazardous municipal waste. The analysis of the combustion properties of a mixture of wood chips and 20–30% of municipal solid waste showed an improvement in the operating parameters of the combustion process. Analysis also confirmed that the co-combustion of dirty fuels and biomass reduced the risk of releasing minerals and heavy metals from fuel into the natural environment. Approximately 55% of the heavy metals passed into the ash. The analysis of municipal solid waste and fuel mixtures containing municipal solid waste for polycyclic aromatic hydrocarbons showed the risk of increasing polycyclic aromatic hydrocarbon concentrations in flue gases.


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