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1.
Int J Environ Health Res ; : 1-13, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711212

RESUMO

Several coal-fired power plants (CFPPs) were built in South Africa, mainly in the central Mpumalanga Province, due to an increase in the demand for Eskom, the national power utility, to keep up with socio-economic growth. The CFPPs, of which 90% are owned by Eskom, generate a significant share of the country's electricity but contribute to the air pollution experienced in the country. The paper discusses sulphur dioxide (SO2), nitrogen dioxide (NO2) and particulate matter of size less than 10 micrometre (µm) in diameter (PM10), using data from 2014 to 2018. The statistics revealed higher PM10 concentrations during winter than in summer and spring at the Kriel and Komati sites; associated with the higher contribution of domestic burning. The study's results could influence legislation and policies and help to understand the source of poor ambient air quality by assessing the three pollutants within the area of the selected power plants.

2.
Sci Total Environ ; 825: 154011, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35192810

RESUMO

Worldwide, numerous rural communities and low-income groups depend on fish harvested by subsistence fishers from local rivers and its impoundments as a source of protein. The aim of the present study was to determine the trace element bioaccumulation (As, Cd, Cr, Cu, Ni, Pb, Pt, Zn) in three edible fish species (Cyprinus carpio, Clarias gariepinus, Oreochromis mossambicus) from two impoundments in the Hex River system, South Africa, as well as the chronic health risk these trace elements pose to regular fish consumers. Trace element concentrations in the Hex River are naturally high (geogenic source), however, increased anthropogenic activities, such as intensive platinum mining activities, elevate the already high background concentrations. Concentrations of As, Cr, and Pt in C. carpio and C. gariepinus, as well as Ni and Zn in O. mossambicus were significantly higher in the impacted impoundment as compared to the reference impoundment. Concentrations of Cr and Cu were at both sampling sites the highest in O. mossambicus. From the human health risk assessment, As poses non-carcinogenic (HQ = 2-7) and carcinogenic risks (33-93 out of 10,000 people), while Cr (3-10 out of 10,000 people) and Ni (2-6 out of 10,000 people) pose only carcinogenic risks for the regular consumption of all three fish species from both impoundments, indicating a high probability of adverse human health effects. For As, Cr and Ni, also the sediment concentrations exceeded the levels of concern within the consensus based sediment quality guideline (CBSQG), while Cd, Cu, Ni and Zn exceeded the water quality guideline values. Thus, the CBSQG approach could be a promising tool for predicting human health risk associated with fish consumption. Since the present study only focused on the individual trace element risks, mixed toxicity of these trace elements and possible other pollutants within these fish species may pose an even greater risk to people who consume these fish regularly.


Assuntos
Carpas , Metais Pesados , Oligoelementos , Poluentes Químicos da Água , Animais , Cádmio , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Medição de Risco , Rios , Oligoelementos/análise , Poluentes Químicos da Água/análise
3.
Sci Total Environ ; 703: 134738, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31731169

RESUMO

South Africa is the world's main supplier of Pt. The Bushveld Igneous Complex in South Africa contains 75% of the world's Pt resources. Mining of this precious metal requires large volumes of water for production and removal of waste products. Most of this wastewater is discharged into river systems. Although the source of contamination with Pt in aquatic systems due to mining activities is known, little to no information is available about the impact of Pt on aquatic organisms. Additionally, other metals are released as byproducts of Pt mining, which might also be discharged into the environment. Therefore, concentrations of Cr, Ni, Cu, Zn, Cd, Pt and Pb were determined in water, sediment and macroinvertebrate samples from a reference site (Site 1), a highly impacted site (Site 2) and a moderately impacted site (Site 3) along the Hex River, South Africa. Aquatic invertebrate families representing different functional feeding groups i.e. scraper-grazers (Lymnaeidae), collector-gatherers (Potamonautidae, Hydropsychidae, Tubificidae and Chironomidae), shredders (Baetidae) and predators (Coenagrionidae and Libellulidae) were studied. In the sediments, the concentrations of Cr and Pt were significantly higher at Site 2 than at Sites 1 and 3, respectively, whereas concentrations of Ni, Cu, Cd, and Pb showed no significant differences between the sites. Depending on the metal, the aquatic invertebrate families showed different grades of bioaccumulation. The results from especially Lymnaeidae, Baetidae, Tubificidae and Chironomidae showed great promise for the use of these taxa for biomonitoring of metal contaminations. The macroinvertebrates accumulated metals associated with Pt mining, with epi-benthic dwelling taxa (Tubificidae) accumulating higher concentrations of Pt and Cr than other families (e.g. Potamonautidae, Coenagrionidae and Lymnaeidae). These results provide valuable information on the behavior of metals related to Pt mining in aquatic ecosystems and therefore can contribute to the risk assessment of these intensive mining activities.


Assuntos
Mineração , Animais , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos , Invertebrados , Platina , Rios , África do Sul , Poluentes Químicos da Água
4.
Int J Parasitol Parasites Wildl ; 10: 207-210, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31667083

RESUMO

This study reports on the first evidence of genomic material of the causative agent for epizootic ulcerative syndrome (EUS), Aphanomyces invadans, from fish in the Limpopo River system and the Kruger National Park, South Africa. Fourteen fish species were collected from various depressions in the floodplains of the Limpopo and Luvuvhu Rivers in the Makuleke Wetlands during 2015 and 2017. A single individual of Clarias gariepinus was found to have a suspected epizootic ulcerative syndrome (EUS) lesion. Samples were collected and evidence of A. invadans DNA in the samples was found through PCR and amplicon sequencing. The spread of EUS into this premier conservation area is of concern as it could potentially spread across borders and into other naïve river systems with important conservation statuses.

8.
S Afr Med J ; 51(20): 722-4, 1977 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-877789

RESUMO

A case of multiple facial fractures complicated by subcutaneous emphysema, pneumomediastinum and pneumoretroperitoneum, in the absence of intra-abdominal, neck or chest injuries, is described.


Assuntos
Enfisema/etiologia , Fraturas Mandibulares/complicações , Fraturas Maxilares/complicações , Enfisema Mediastínico/etiologia , Adulto , Humanos , Masculino , Espaço Retroperitoneal , Enfisema Subcutâneo/etiologia
10.
Onderstepoort J Vet Res ; 44(1): 29-38, 1977 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26901

RESUMO

A brief survey of the literature on gamma-glutamyl transpeptidase (gamma-GT) activity is included in this study. The levels of activity in the serum of normal Merino sheep (13,6-32,4 mI.U/ml) were ascertained as a preliminary to following the activity through the entire course of experimentally induced ovine lupinosis, a hepatotoxicosis caused by Phomopsis leptostromiformis (Kühn) Bubák. The response of the serum level of gamma-GT activity to the course of the disease was compared with that of glutamate oxaloacetic transaminase (GOT) and 2 liver function tests for the purpose of assessing its potential application in the study of this mycotoxicosis. Because the levels of activity of gamma-GT were more valuable for the early diagnosis of low grade acute intoxication and the detection of chronic liver involvement while those of GOT gave better information on the development of severe acute hepato-cellular damage, these 2 enzymes, considered together, were found to give the best information on the course of the toxicosis. The changes in gamma-GT activity during various stages of intoxication were also related to the histopathological lesions in the liver.


Assuntos
Fígado/enzimologia , Micotoxinas/toxicidade , Doenças dos Ovinos/enzimologia , Ovinos/sangue , gama-Glutamiltransferase/sangue , Animais , Feminino , Fígado/patologia , Masculino , Fungos Mitospóricos , Doenças dos Ovinos/patologia
11.
S Afr Med J ; 50(51): 2026-31, 1976 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-795056

RESUMO

The development of the flap transfer technique in plastic and reconstructive surgery has evolved to the stage where free transplantation of a full-thickness skin flap, by means of microvascular anastomosis, has become posssible. For the first time in South Africa, a case is documented where such a free graft was used successfully to reconstruct a severe burn contracture of the neck. Experience with this and subsequent cases has taught valuable lessons about the procedure.


Assuntos
Artérias/cirurgia , Transplante de Pele , Cirurgia Plástica , Veias/cirurgia , Adolescente , Queimaduras/cirurgia , Contratura/cirurgia , Feminino , Humanos , Métodos , Pele/irrigação sanguínea , Transplante Autólogo
12.
J S Afr Vet Assoc ; 47(1): 29-33, 1976 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-4617

RESUMO

A study was made of the acid-base status of Babesia canis infected dogs judged unlikely to recover after specific babesicidal drug therapy despite the use of blood transfusion and other conventional supportive measures. Such cases were invariably acidotic and responded well and often dramatically to supportive intravenous sodium bicarbonate administration. Elevated blood urea nitrogen, also responded gratifyingly to this procedure. The rationale is discussed in some detail.


Assuntos
Acidose/veterinária , Babesiose , Doenças do Cão , Acidose/diagnóstico , Acidose/tratamento farmacológico , Animais , Babesiose/sangue , Bicarbonatos/uso terapêutico , Nitrogênio da Ureia Sanguínea , Dióxido de Carbono/sangue , Doenças do Cão/diagnóstico , Doenças do Cão/tratamento farmacológico , Cães , Feminino , Concentração de Íons de Hidrogênio , Masculino
13.
S Afr Med J ; 49(5): 147-52, 1975 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-1091992

RESUMO

The more common injuries to the skin of the male external genital organs are described; some of these mutilations are unique to the African continent. The extent of trauma ranges from small penile skin defects after circumcision to complete avulsion of the skin of the penis and scrotum. The techniques of reconstruction are described.


Assuntos
Pênis/lesões , Escroto/lesões , Pele/lesões , Adolescente , Adulto , África Austral , Negro ou Afro-Americano/história , População Negra , Castração/história , Comportamento Ritualístico , Criança , Circuncisão Masculina/efeitos adversos , História do Século XV , História do Século XVI , História do Século XVII , Humanos , Masculino , Transplante de Pele , África do Sul , Cirurgia Plástica , Transplante Autólogo
15.
Plast Reconstr Surg ; 47(3): 269-71, 1971 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-5544845
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