scholarly journals Indigenous mercury-resistant bacteria isolated from contaminated soils around artisanal gold processing centers in Sukabumi, Indonesia

2021 ◽  
Vol 909 (1) ◽  
pp. 012009
Author(s):  
F Y Amandita ◽  
Efadeswarni ◽  
Idris ◽  
T Sulistiyani ◽  
A Kanti ◽  
...  
Keyword(s):  
Contaminated Soils ◽  
Gold Mining ◽  
Agricultural Land ◽  
Normal Growth ◽  
Luria Bertani ◽  
Mercury Pollution ◽  
Resistant Bacteria ◽  
Small Scale ◽  
Lag Phase ◽  
Gold Processing

Abstract In Indonesia, the largest mercury pollution comes from artisanal and small-scale gold mining (ASGM), which may cause the distribution of mercury to agricultural land and can be absorbed by food crops. Sukabumi Regency in West Java, well-known as one hotspot of illegal artisanal gold mining and national rice producer, is potentially threatened by mercury pollution. Efforts to remediate mercury contaminated agricultural land can be done by using mercury-reducing bacteria. This research aims to select the most potential indigenous bacteria for mercury remediation. Soil and sludge samples were collected from 2 districts in Sukabumi, where gold processing using mercury is common. Bacteria were selectively isolated from cultured colonies grown in Luria Bertani broth supplemented with HgCl2 30 mg/L. We obtained 27 isolates that belong to 16 species, as identified by API® 20 E and 20 NE (BioMérieux, USA). The growth of each isolate was assessed by measuring the optical density of inoculated LB broth contained HgCl2 30 mg/L for 5 consecutive days. All isolates showed normal growth. The log phase reached its maximum value on the second or third day after inoculation and lag phase afterward. Twelve identified isolates were chosen for evaluation of their resistance to mercury by growing them in Mueller-Hinton agar supplemented with HgCl2 (30 mg/L, 50 mg/L, 100 mg/L, 150 mg/L, and 200 mg/L). Seven isolates were able to grow in media with HgCl2, but only Mer07 survived on HgCl2 150 mg/L.

Myco-phytoremediation of mercury polluted soils in Ghana and Burkina Faso

2020 ◽  
Author(s):  
Sergey Blagodatsky ◽  
Miriam Ehret ◽  
Frank Rasche ◽  
Imke Hutter ◽  
Regina Birner ◽  
...  
Keyword(s):  
Burkina Faso ◽  
Contaminated Soils ◽  
Mycorrhizal Fungi ◽  
Gold Mining ◽  
Mycorrhizal Fungus ◽  
Arbuscular Mycorrhizal ◽  
Mercury Pollution ◽  
Contaminated Sites ◽  
Small Scale ◽  
Environmental Damage

<p>Unregulated surface gold mining contributes to deforestation and land degradation in Ghana and Burkina Faso (West Africa). In addition, small-scale gold mining uses a technology for gold amalgamation that pollutes the environment with mercury (Hg) and adversely affects human health. In the framework of the recently started Mercury-AMF-project we aim to reduce the environmental damage caused by mercury used in gold mining in Ghana and Burkina Faso. This will be achieved by developing and implementing novel arbuscular mycorrhizal fungi (AMF) - plant systems as a strategy to reclaim mercury-contaminated sites. The cultivation of pioneer plants on contaminated soils can reduce the mercury pollution. Symbiotic mycorrhizal associations of those plants may strengthen the potential to remediate Hg-contaminated soils.</p><p>The implementation of the project is based on the following specific activities:</p><ol><li>Characterization of the arbuscular mycorrhizal fungus (AMF) candidates in the soils of Ghana and Burkina Faso;</li> <li>Development of prototype AMF plant systems as an innovative strategy for the remediation of Hg-contaminated sites;</li> <li>Testing of mycophytoextraction methods to reduce the Hg soil concentration below threshold values;</li> <li>Examination of the return of Hg-contaminated sites to agricultural use and the promotion of sustainable land management in gold mining regions;</li> <li>Set-up of modelling approaches for the efficiency of mycophytoextraction methods and Hg plant uptake;</li> <li>Exploration and communication of institutional and socio-economic framework conditions for the introduction of AMF plant systems.</li> </ol><p>During the first year of the project soil and plant sampling campaigns in Ghana and Burkina Faso were organised for screening the AMF-candidates capable for symbiosis with local plant species and tolerant to the mercury pollution. Clarification of possible mechanisms of phytoremediation is the next essential component of the research: several pathways of decontamination are possible including phytostabilization, phytovolatilization and phytoextraction. Based on the first results, field experimental trials with new AMF-plant systems will be established.</p>

scholarly journals Identification of mercury‐resistant Streptomyces isolated from Cyperus rotundus L. rhizosphere and molecular cloning of mercury (II) reductase gene

2021 ◽  
Vol 26 (4) ◽  
pp. 206
Author(s):  
Wahyu Aristyaning Putri ◽  
Hanum Mukti Rahayu ◽  
Anis Uswatun Khasanah ◽  
Langkah Sembiring ◽  
Masashi Kawaichi ◽  
...  
Keyword(s):  
Gold Mining ◽  
Full Length ◽  
Cyperus Rotundus ◽  
Cloning And Expression ◽  
Expression Vectors ◽  
Resistant Bacteria ◽  
Small Scale ◽  
Rrna Gene ◽  
Reductase Gene ◽  
Mera Gene

Streptomyces is one of mercury‐resistant bacteria which can convert Hg2+ into nontoxic Hg0 . This study aimed to identify mercury‐resistant Streptomyces present in the Cyperus rotundus rhizosphere from artisanal small‐scale gold mining (ASGM) area and clone merA gene to the cloning and expression vectors. Molecular identification was conducted using 16s rRNA gene with the maximum likelihood algorithms. Results revealed that the AS1 and AS2 strains were a group of Streptomyces ardesiacus and the BR28 strain was closed to Brevibacillus agri. The AS2 merA gene was cloned to pMD20 cloning vectors, pGEX‐5x‐1 and pET‐28c expression vectors. The transformation was successfully performed in BL21 and DH5α competent cells. The full length of the merA gene was confirmed to be 1,425 bp. This study is the first research on identifying mercury‐resistant Streptomyces and cloning the full‐length merA gene in Indonesia.

scholarly journals Mercury Contamination from Dental Amalgam

2019 ◽  
Vol 9 (22) ◽  
Author(s):  
Anita Vazquez Tibau ◽  
Blanche D. Grube
Keyword(s):  
Sewage Sludge ◽  
Gold Mining ◽  
Negative Impact ◽  
Developed Countries ◽  
The United States ◽  
Dental Amalgam ◽  
Mercury Pollution ◽  
Mercury Contamination ◽  
Small Scale ◽  
The European Union

Background. Mercury in dental amalgam is a hidden source of global mercury pollution, resulting from the illegal diversion of dental mercury into the artisanal and small-scale gold mining sector, to crematoria emissions from the deceased and sewage sludge that is sold to farmers. These significant mercury sources result in air, water, and food contamination that consequently have a negative impact on human health. Objectives. The aim of the present study was to investigate and report on all of the various pathways mercury in dental amalgam can enter the environment. Methods. The present study searched the electronic data bases of PubMed and Google Scholar. Peer reviewed journals and references of studies included for full-text review were examined for potentially relevant studies. Articles published between 2000 to 2018 were searched and specifically screened for articles that referenced “Dental Amalgam,” and the following key words in various combinations: “Minamata Convention on Mercury Treaty,” “Sewage Sludge,” “Cremation,” and “Artisanal and Small-Scale Gold Mining.” Data were included on the most populous countries of China, India, the United States, Brazil, and the European Union collectively. We also included data on cremation statistics and current global trends, looking at populations where cremation is a common practice, such as Japan and India. Discussion. Dental amalgam represents a significant, but understudied area of global mercury pollution that includes cremation, sewage sludge, burial, and small-scale gold mining. Conclusions. Mercury used in products and processes, including dental amalgams, is a global pollutant. Even after the last mercury dental amalgam is placed, its toxic legacy will continue for decades, because of its pervasive bioaccumulation in the environment. Government regulatory agencies should make it mandatory to utilize available technologies, not only in developing countries, but also in developed countries, to reduce mercury contamination. Competing Interests. The authors declare no competing financial interests.

scholarly journals An Integrated Approach to Assess the Environmental Impacts of Large-Scale Gold Mining: The Nzema-Gold Mines in the Ellembelle District of Ghana as a Case Study

2021 ◽  
Vol 18 (13) ◽  
pp. 7044
Author(s):  
Dawuda Usman Kaku ◽  
Yonghong Cao ◽  
Yousef Ahmed Al-Masnay ◽  
Jean Claude Nizeyimana
Keyword(s):  
Environmental Impacts ◽  
Large Scale ◽  
Gold Mining ◽  
Vegetation Index ◽  
Agricultural Land ◽  
Small Scale ◽  
Bare Area ◽  
Double Phase ◽  
Gold Producer

The mining industry is a significant asset to the development of countries. Ghana, Africa’s second-largest gold producer, has benefited from gold mining as the sector generates about 90% of the country’s total exports. Just like all industries, mining is associated with benefits and risks to indigenes and the host environment. Small-scale miners are mostly accused in Ghana of being environmentally disruptive, due to their modes of operations. As a result, this paper seeks to assess the environmental impacts of large-scale gold mining with the Nzema Mines in Ellembelle as a case study. The study employs a double-phase mixed-method approach—a case study approach, consisting of site visitation, key informant interviews, questionnaires, and literature reviews, and the Normalized Difference Vegetation Index (NDVI) analysis method. The NDVI analysis shows that agricultural land reduced by −0.98%, while the bare area increases by 5.21% between the 2008 and 2015 periods. Our results show that forest reserves and bare area were reduced by −4.99% and −29%, respectively, while residential areas increased by 28.17% between 2015 and 2020. Vegetation, land, air, and water quality are highly threatened by large-scale mining in the area. Weak enforcement of mining policies, ineffective stakeholder institution collaborations, and limited community participation in decision-making processes were also noticed during the study. The authors conclude by giving recommendations to help enhance sustainable mining and ensure environmental sustainability in the district and beyond.

Sign in / Sign up

Export Citation Format

Share Document