| 1. |
- Haller, Henrik, 1977-, et al.
(författare)
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Bioaccumulation and translocation of field-weathered toxaphene and other persistent organic pollutants in three cultivars of amaranth (A. cruentus ‘R127 México’, A. cruentus ‘Don León’ y A. caudatus ‘CAC 48 Perú’) – A field study from former cotton fields in Chinandega, Nicaragua
- 2018
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Ingår i: Ecological Engineering. - : Elsevier BV. - 0925-8574 .- 1872-6992. ; 121, s. 65-71
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Tidskriftsartikel (refereegranskat)abstract
- Soils polluted by persistent organic pollutants threatens habitats for plants and animals as well as basic human needs such as food security and provision of potable water. Toxaphene is a persistent organic pollutant that was heavily used as a pesticide in Central America, Brazil, Soviet Union etc. until it was banned in 1993. The objective of this study was to determine the bioaccumulation and translocation characteristics of three different cultivars of amaranth in soils contaminated with field-weathered toxaphene and other POPs in former cotton fields in Chinandega, Nicaragua to identify safety issues for human consumption and/or potential for phytoremediation. The concentration of toxaphene and other POPs in the edible parts of the amaranth (leaves and seeds) exceeded the maximum residue level for human consumption established by the European Union for most of the tested compounds. Concentrations of toxaphene congeners and other POPs were found in all vegetative organs. Many substances were accumulated to concentrations more than 10 times higher than in the soil. Of the three cultivars, A. caudatus 'CAC48 Perú' and A. cruentus 'Don Leon' presented the highest average BAF. None of the 3 cultivars can be considered a panacea hyperaccumulator for either toxaphene alone or in conjunction with other POPs but since many agricultural soils comprise a range of different contaminants, the broad-spectrum bioaccumulating capacity of amaranth can make it an interesting candidate for phytoremediation.
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| 2. |
- Lacayo-Romero, Martha, et al.
(författare)
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Degradation of toxaphene in aged and freshly contaminated soil
- 2006
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 63:4, s. 609-615
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Tidskriftsartikel (refereegranskat)abstract
- Degradation of toxaphene in soil from both newly contaminated (from Sweden) and aged spills (from Nicaragua) were studied. The newly contaminated soil contained approximately 11 mg kg(-1) toxaphene while the aged Nicaraguan soil contained approximately 100 mg kg(-1). Degradation was studied in anaerobic bioreactors, some of which were supplied with lactic acid and others with Triton X-114. In this study we found that the lower isomers Parlar 11, 12 were degraded while the concentration of isomer Parlar 15 increased. This supported an earlier evaluation which indicated that less chlorinated isomers are formed from more heavily isomers. Lactic acid when added to the soil, interfere with the degradation of toxaphene. Lactic acid was added; several isomers appeared to degrade rather slowly in newly contaminated Swedish soil. The Swedish soil, without any external carbon source, showed the slowest degradation rate of all the compounds studied. When Triton X-114 at 0.4 mM was added, the degradation rate of the compounds increased. This study illustrates that biodegradation of toxaphene is a complex process and several parameters have to be taken into consideration. Degradation of persistent pollutants in the environment using biotechnology is dependent on bioavailability, carbon sources and formation of metabolites.
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| 3. |
- Pronoza, Lesya, et al.
(författare)
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The use of an integrated planning guide to steer phytoremediation projects towards sustainability using the example of Amaranth (Amaranthus) to remediate toxaphene polluted soils in a tropical region
- 2016
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Ingår i: Proceedings of the Linnaeus Eco-Tech 2016 International Conference on Natural Sciences and Technologies for Waste and Wastewater Treatment, Remediation, Emissions Related to Climate, Environmental and Economic Effects.. - Kalmar : Linnaeus University. - 9789188357410
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Soil pollution by pesticides is a serious problem, especially in developing countries where incentives are limited to remediate these soils. Toxaphene was a widely used insecticide during the 1950s – 1980s, but even after a total ban on its use in 2001 there are still many harmful consequences that can be observed. High levels of toxaphene on agriculture fields in Nicaragua continues to be a threat to local inhabitants and wildlife and to the surrounding ecosystems. Phytoremediation is one of the methods used for cleaning polluted soils. It requires growing plants in-situ and relies on their ability to absorb and accumulate or degrade toxic elements. Some advantages are environmental safety and cost-effectiveness.Amaranth (Amaranthus) was investigated as a primary candidate for the phytoremediation project. Beside this, some other plants, such as Cucurbita pepo, Spinacia oleracea, Medicago sativa, were reported to be able to successfully absorb common persistent organic pollutants. In addition, uptake mechanisms and patterns of distribution of toxic elements in plants were studied to determine further use of plants.To assess the viability and sustainability potential of implementing amaranth for phytoremediation, an Integrated Planning Guide (IPG) was used. The IPG uses a number of principles and concepts to provide guidelines for bioremediation actions. As a result, several conclusions and suggestions were produced, the most important being: amaranth has a potential for toxaphene uptake and has a high yield and historical significance; locally available poultry manure can be used as a fertilizer for amaranth; a monoculture should be avoided while growing amaranth; local community is the main driver of success and beneficiary of the project. Further research should be undertaken on this matter to improve the understanding of key factors for the success of the project.
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