Using pollution indices to develop a risk classification tool for gold mining contaminated soils.

The presence of potentially toxic elements (PTEs) in soil and plants is a risk factor to human well-being and the environment. Soil and leaves from a traditional medicinal plant, known as the sweet thorn plant, were assessed to determine the extent of pollution by PTEs from gold mine tailings in a case study area of Matjhabeng Local Municipality, South Africa. A risk classification tool was developed using the different indicators of pollution quantified to describe the pollution risk at each sampling site.

Assessment of water, sanitation, and hygiene target and theoretical modeling to determine sanitation success in sub-Saharan Africa.

Unlabelled: Accessing the status of clean drinking water, sanitation, and hygiene remains a challenge in sub-Saharan Africa (SSA). The current article contributes to the progress made by the WASH initiatives in ten SSA countries in eliminating open defecation by 2030, using theoretical data from 2017 to 2019. The authors used regression trend estimation to observe that rural and urban population growth had a statistically significant detrimental influence on the elimination of open defecation by 2030.

Aquatic Environment Exposure and Toxicity of Engineered Nanomaterials Released from Nano-Enabled Products: Current Status and Data Needs.

Rapid commercialisation of nano-enabled products (NEPs) elevates the potential environmental release of engineered nanomaterials (ENMs) along the product life cycle. The current review examined the state of the art literature on aquatic environment exposure and ecotoxicity of product released (PR) engineered nanomaterials (PR-ENMs). Additionally, the data obtained were applied to estimate the risk posed by PR-ENMs to various trophic levels of aquatic biota as a means of identifying priority NEPs cases that may require attention with regards to examining environmental implications.

Will the extraction of COVID-19 from wastewater help flatten the curve?

With the potentially fatal effect of COVID-19 and its devastating impact on economies worldwide, some environmental scientist has suggested the use of waste from household sewage to trace the movement of SARS-CoV-2, within a given country. However, this approach is not without challenges where developing countries lack proper and adequate hygiene and sanitation, resulting in widespread defecation. Limited scientific research has been done to determine how many times a recently infected person can defecate and the quantification of SARS-CoV-2 found in a single expel.

Dataset of metal(loid) concentrations recorded in the tissues of two fish species from Flag Boshielo Dam, South Africa.

Metal(loid) pollution in aquatic ecosystems has become a cause for concern, particularly in areas where communities depend on services from these systems for their livelihood. This dataset presents the metal(loi) concentrations recorded in the water column, bottom sediment, and tissues of and from Flag Boshielo Dam, an impoundment in one of the most polluted river systems in Southern Africa, the Olifants River. The concentrations of metal(loid)s were measured using inductively coupled plasma-optical emission spectrophotometry (ICP-OES; Perkin Elmer, Optima 2100DV).

Metal levels in two fish species from a waterbody impacted by metallurgic industries and acid mine drainage from coal mining in South Africa.

The Loskop Dam in South Africa is the most contaminated waterbody in the Olifants River which is a transboundary river that flows into Mozambique. The present study measured selected metal concentrations in the muscle of and from Loskop Dam, and assessed the human health risks associated with consumption of these fish species. Trace metals were below detection level in the surface water whereas bottom sediment exhibited relatively higher concentrations.

The Presence of Toxic and Non-Toxic Cyanobacteria in the Sediments of the Limpopo River Basin: Implications for Human Health.

The presence of harmful algal blooms (HABs) and cyanotoxins in drinking water sources poses a great threat to human health. The current study employed molecular techniques to determine the occurrence of non-toxic and toxic cyanobacteria species in the Limpopo River basin based on the phylogenetic analysis of the 16S rRNA gene. Bottom sediment samples were collected from selected rivers: Limpopo, Crocodile, Mokolo, Mogalakwena, Nzhelele, Lephalale, Sand Rivers (South Africa); Notwane (Botswana); and Shashe River and Mzingwane River (Zimbabwe).

Development of a diatom-based multimetric index for acid mine drainage impacted depressional wetlands.

Acid mine drainage (AMD) from coal mining in the Mpumalanga Highveld region of South Africa has caused severe chemical and biological degradation of aquatic habitats, specifically depressional wetlands, as mines use these wetlands for storage of AMD. Diatom-based multimetric indices (MMIs) to assess wetland condition have mostly been developed to assess agricultural and urban land use impacts. No diatom MMI of wetland condition has been developed to assess AMD impacts related to mining activities.

An evaluation of the endocrine disruptive potential of crude oil water accommodated fractions and crude oil contaminated surface water to freshwater organisms using in vitro and in vivo approaches.

Knowledge regarding the potential impacts of crude oil on endocrine signaling in freshwater aquatic vertebrates is limited. The expression of selected genes as biomarkers for altered endocrine signaling was studied in African clawed frog, Xenopus laevis, tadpoles and juvenile Mozambique tilapia, Oreochromis mossambicus, exposed to weathered bunker and unweathered refinery crude oil water accommodated fractions (WAFs). In addition, the expression of the aforementioned genes was quantified in X.

Applying genotoxicology tools to identify environmental stressors in support of river management.

Although bioassay approaches are useful for identifying chemicals of potential concern, they provide little understanding of the mechanisms of chemical toxicity. Without this understanding, it is difficult to address some of the key challenges that currently face aquatic ecotoxicology. To overcome this, the toxicity potential of the water samples was assessed and surviving organisms (Physa acuta) were used for protein activity measurements and gene expression profiling by making use of complementary DNA amplified fragment length polymorphism (cDNA-AFLP) analysis.

The potential of selected macroalgal species for treatment of AMD at different pH ranges in temperate regions.

The metal bioaccumulation potential of selected macroalgae species at different pH ranges was study for usage as part of a possible secondary passive acid mine drainage (AMD) treatment technology in algae ponds. Two separate studies were conducted to determine the suitability of macroalgae for passive treatment when metabolic processes in macrophytes and microorganisms in constructed wetlands decrease during winter months. In the field study, the bioconcentration of metals (mg/kg dry weight) measured in the benthic macroalgae mats was in the following order: site 1.

The impacts of neutralized acid mine drainage contaminated water on the expression of selected endocrine-linked genes in juvenile Mozambique tilapia Oreochromis mossambicus exposed in vivo.

Acid mine drainage (AMD) is a global environmental concern due to detrimental impacts on river ecosystems. Little is however known regarding the biological impacts of neutralized AMD on aquatic vertebrates despite excessive discharge into watercourses. The aim of this investigation was to evaluate the endocrine modulatory potential of neutralized AMD, using molecular biomarkers in the teleost fish Oreochromis mossambicus in exposure studies.

Bioaccumulation of aluminium and iron in the food chain of Lake Loskop, South Africa.

Concentrations of total aluminium (Al) and iron (Fe) were determined in Lake Loskop over a period of four months in 2009 in samples of phytobenthos, phytoplankton, macroinvertebrates, amphibians and fish. The highest concentrations of Al and Fe were measured in the filamentous algae Spirogyra fluviatilis (Hillse) and Spirogyra adanata (Kütz), (Al=18,997.5mgkg(-1) dry weight and Fe=22,054.

Phytobenthos and phytoplankton community changes upon exposure to a sunflower oil spill in a South African protected freshwater wetland.

The occurrence of a sunflower oil spill in 2007 in the Con Joubert Bird Sanctuary freshwater wetland, South Africa, inhibited the growth of sensitive phytoplankton species and promoted that of tolerant species. The algal divisions Chlorophyta and Euglenophyta were well represented in the sunflower oil contaminated water, especially the species Euglena sociabilis, Phacus pleuronectes and Chlamydomonas africana. Young and mature resting zygotes of Chlamydomonas africana were recorded in high abundance at all the sunflower oil contaminated sampling sites.

Identification of toxigenic Microcystis strains after incidents of wild animal mortalities in the Kruger National Park, South Africa.

The eutrophic process potentially caused by a high urine and faecal load resulting from an unusually high hippopotamus (Hippopotamus amphibious) density in the Nhlanganzwane Dam, Kruger National Park, South Africa, triggered a chain of events characterised by an increase in the growth of primary producers (Microcystis aeruginosa). This increase in M. aeruginosa biomass was followed by bio-intoxication incidents in wild animals.

The influence of a toxic cyanobacterial bloom and water hydrology on algal populations and macroinvertebrate abundance in the upper littoral zone of Lake Krugersdrift, South Africa.

The biological interactions and the physical and chemical properties of the littoral zone of Lake Krugersdrift were studied for a 4-month period when a dense, toxic cyanobacterial bloom dominated by Microcystis aeruginosa was present in the main lake basin. The presence of a toxic strain of M. aeruginosa was confirmed through the use of ELISA and molecular markers that detect the presence of the mcyB and mcyD genes of the mcy gene cluster that synthesizes microcystin.