Single and combined effects of metal-based fungicides on Eisenia andrei in different scenarios of climatic change.

This study evaluated the ecotoxicity of metal-based fungicides under the current scenarios of global climatic change (20 °C and 25 °C) and moisture content (30% and 50%) in single and binary mixtures of copper oxychloride (CuOx) [200, 500 and 1000 mg/kg] and mancozeb (MnZn) [44, 850 and 1250 mg/kg]. Endpoints assessed included mortality, changes in biomass, avoidance behaviour, and reproduction utilising standardised protocols (ISO and OECD). The changes in biomass and mortality tests lasted 28 days, followed by a 28-day reproduction test and a two-day avoidance test.

Ecotoxicological Effects of Aflatoxins on Earthworms under Different Temperature and Moisture Conditions.

Aflatoxin contamination remains one of the most important threats to food safety and human health. Aflatoxins are mainly found in soil, decaying plant material and food storage systems and are particularly abundant during drought stress. Regulations suggest the disposal of aflatoxin-contaminated crops by incorporation into the soil for natural degradation.

Do Endemic Soil Fauna Species Deserve Extra Protection for Adverse Heavy Metal Conditions?

The concept of Ecotoxicological Species Sensitivity Distributions, as used in EU and US, to derive environmental standards for contaminants, starts from the assumption that by protecting the majority of species (95% confidence interval) all species will be protected. Nevertheless, 5% of the species outside the confidence interval might become harmed; half of it being the most sensitive for the particular compound tested. With respect to protection of rare endemic species it is not clear, however, if contamination is a driving factor for endemicity.

Global Trends of Green Pesticide Research from 1994 to 2019: A Bibliometric Analysis.

The fast-growing world population places food production under enormous pressure to ensure food security. One of the most common methods to increase food production is the use of pesticides, but the continuous use thereof has numerous detrimental effects on the environment. The interest in biopesticides for a possible substitute has grown over the past two decades.

Aflatoxins in the soil ecosystem: an overview of its occurrence, fate, effects and future perspectives.

Aflatoxins are secondary metabolites produced by specific strains of fungi, especially Aspergillus spp. These natural toxins are mainly found in soil, decaying vegetation and food storage systems and are particularly abundant during drought stress. Aflatoxin contamination is one of the most important threats to food safety and human health due to its toxic, mutagenic and carcinogenic properties.

Structural and functional differentiation of bacterial communities in post-coal mining reclamation soils of South Africa: bioindicators of soil ecosystem restoration.

Soil microbial communities are suitable soil ecosystem health indicators due to their sensitivity to management practices and role in soil ecosystem processes. Presently, information on structural and functional differentiation of bacterial communities in post-coal mining reclamation soils of South Africa is sparse. Here, bacterial communities in three post-coal mining reclamation soils were investigated using community-level physiological profiling (CLPP), enzyme activities, and next-generation sequencing of 16S rRNA gene.

Heavy Metal Threats to Plants and Soil Life in Southern Africa: Present Knowledge and Consequences for Ecological Risk Assessment.

In recent times there has been remarkable development in the field of soil ecotoxicology and risk assessment (RA) models. It is, however, debatable if these RA models are robust representatives for worldwide relevance. In order to investigate this, the current overview aims to address heavy metal threats to soil life in southern Africa by investigating present knowledge and consequences for RA using research in southern Africa as a case.

Sublethal Effects of Ionic and Nanogold on the Nematode .

The nematode is used as an ecotoxicological model species in both aqueous medium and solid substrates. It is easy and of low cost to maintain in the laboratory and it produces hundreds of offspring within a short period of time. It also has a small body size (1 mm), making it possible for assays to be conducted in 12-well plates.

Effect of Bacillus cereus on the ecotoxicity of metal-based fungicide spiked soils: Earthworm bioassay.

Soil microorganisms exhibit varying levels of metal tolerance across a diverse range of environmental conditions. The use of metal-based fungicides such as mancozeb and copper oxychloride could potentially result in increased levels of manganese, zinc and copper which may adversely affect soil mesofauna. Under standardized earthworm bioassay conditions (temperature, pH, soil type and water content), we investigated the effect of Bacillus cereus on mancozeb and copper oxychloride ecotoxicity towards Eisenia andrei.

Tolerance and growth kinetics of bacteria isolated from gold and gemstone mining sites in response to heavy metal concentrations.

Response and growth kinetics of microbes in contaminated medium are useful indices for the screening and selection of tolerant species for eco-friendly bio-augmentative remediation of polluted environments. In this study, the heavy metal (HM) tolerance, bioaccumulation and growth kinetics of seven bacterial strains isolated from mining sites to 10 HMs (Cd, Hg, Ni, Al, Cr, Pb, Cu, Fe, Mn and Zn) at varied concentrations (25-600 mgL) were investigated. The isolates were phylogenetically (16S rRNA gene) related to Lysinibacillus macroides, Achromobacter spanius, Bacillus kochii, B.

Heavy metal tolerance traits of filamentous fungi isolated from gold and gemstone mining sites.

Increased environmental pollution has necessitated the need for eco-friendly clean-up strategies. Filamentous fungal species from gold and gemstone mine site soils were isolated, identified and assessed for their tolerance to varied heavy metal concentrations of cadmium (Cd), copper (Cu), lead (Pb), arsenic (As) and iron (Fe). The identities of the fungal strains were determined based on the internal transcribed spacer 1 and 2 (ITS 1 and ITS 2) regions.

Amelioration of iron mine soils with biosolids: Effects on plant tissue metal content and earthworms.

The achievement of environmentally sound and economically feasible disposal strategies for biosolids is a major issue in the wastewater treatment industry around the world, including Swaziland. Currently, an iron ore mine site, which is located within a wildlife sanctuary, is being considered as a suitable place where controlled disposal of biosolids may be practiced. Therefore, this study was conducted to investigate the effects of urban biosolids on iron mine soils with regard to plant metal content and ecotoxicological effects on earthworms.

Preliminary evidence of differences in cadmium tolerance in metal-free stocks of the standard earthworm test species Eisenia andrei (Oligochaeta).

To test whether metal-tolerant and metal-sensitive earthworm specimens could be an inherent part of metal-free earthworm populations, (i) we used DNA barcoding to identify and categorize earthworms from 8 populations of the standard test species Eisenia andrei, and (ii) the earthworms carrying three of the identified COI haplotypes (named Hap1, hap3 and Hap3) were paired up and exposed to Cd in order to assess the difference in Cd sensitivity between the breeding pairs. A total of six breeding pairs were exposed to 0, 25, 50 and 100 mg Cd/kg for 4 weeks at 20 °C. The survival of the breeding pairs, their change in biomass and cocoon production were assessed.

A greenhouse trial to investigate the ameliorative properties of biosolids and plants on physicochemical conditions of iron ore tailings: Implications for an iron ore mine site remediation.

An iron ore mine site in Swaziland is currently (2015) in a derelict state as a consequence of past (1964-1988) and present (2011 - current) iron ore mining operations. In order to control problems associated with mine wastes, the Swaziland Water Services Corporation (SWSC) recently (2013) proposed the application of biosolids in sites degraded by mining operations. It is thought that this practice could generally improve soil conditions and enhance plant reestablishment.

Utilizing an earthworm bioassay (Eisenia andrei) to assess a South African soil screening value with regards to effects from a copper manufacturing industry.

Metal contamination of soil due to industrialization has become an increasingly important problem in South Africa. This study aimed to investigate the potential impact of a copper (CuSO4·5H2O) production company on the soil environment. Bioassays using Eisenia andrei were performed to assess changes in biomass, reproduction and a biomarker, neutral red retention time, over a 28 day period.

The enchytraeid reproduction test (ERT): A potentially quick and affordable tool for the assessment of metal contaminated soils in emerging economies.

The enchytraeid reproduction test (ERT) was used to assess the ecotoxicity of selected mine tailings and agricultural soils from South Africa. The mine tailings had higher cumulative metal concentrations than agricultural soils. The most contaminated mine tailings significantly reduced the survival of the oligochaete Enchytraeus doerjesi whose reproduction was suppressed in all mine waste substrates.

Effects of Cry1Ab transgenic maize on lifecycle and biomarker responses of the earthworm, Eisenia andrei.

A 28-day study was conducted to determine the effects of the Bacillus thuringiensis Cry1Ab toxin on the earthworm Eisenia andrei. Previously, investigations have been limited to life-cycle level effects of this protein on earthworms, and mostly on E. fetida.

Utilizing Eisenia andrei to assess the ecotoxicity of platinum mine tailings disposal facilities.

South Africa is an important platinum mining country which results in environmental impacts due to the construction of tailing disposal facilities (TDFs). It is unclear what the effects of ageing are on the ecotoxicity of TDFs and whether it increases or decreases over time. The aim of this study was to determine the ecotoxicity of differently aged TDFs by investigating earthworm (Eisenia andrei) responses viz.