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1.
Bull Environ Contam Toxicol ; 112(2): 29, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38281207

RESUMO

Little is known about microplastics (MPs) in adult frogs. We investigated MPs in adult Common River Frogs (Amietia delalandii) from Potchefstroom, South Africa. Five kinds of samples were analysed: natural water, water used to rinse the skin, skin, intestine, and the remainder of the body (corpus). Tissues were digested. Microplastics occurred in all frogs and sample types (1128 MPs counted). Fibres were the most prevalent MP. Fibre lengths were between 28 and 4300 µm, either polyester or polyvinyl alcohol. MPs in skin were likely derived from the ambient, and MPs in the corpus from translocation via the skin. Fibres in tissues were significantly shorter in larger frogs, a phenomenon we provisionally assign to in situ biodegradation. Microplastics in frogs can potentially be transferred through the food web to higher trophic levels. This study provides the first evidence of MPs in adult frog tissues and avenues for further investigations.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Plásticos , Poluentes Químicos da Água/análise , Rios , Anuros , Água , Monitoramento Ambiental
2.
Arch Environ Contam Toxicol ; 81(3): 347-366, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34480207

RESUMO

There is little information on how POPs in eggs of different terrestrial, wetland, and aquatic birds share a large urban and rural landscape relate. We collected and analysed 64 eggs belonging to ten species of six feeding guilds, and compared organic chlorinated pesticide (OCP), polychlorinated biphenyl (PCB), and brominated flame retardants (BFR) residue concentrations and compositions. The eggs were collected in the Gauteng and the northern part of the Free Sate provinces of South Africa, one of the largest economic hubs in Africa. White-breasted Cormorant and African Darter eggs (at the highest trophic level as large aquatic predators) had the highest ΣOCP and ΣPCB concentrations, and Cape Sparrow and Southern Masked Weaver (granivores) eggs had the lowest concentrations, corresponding to the lowest trophic level in our collection. The highest percentage p,p'-DDT were in eggs of the terrestrial insectivore Crowned Lapwing (24%) and the scavenging African Sacred Ibis (17%), and the lowest in African Darter (1.0%) and White-breasted Cormorant (0.9%) eggs, suggesting that recency of DDT releases in a region cannot be gauged by this metric. African Sacred Ibis and Southern Masked Weaver eggs had the highest ΣBFR concentrations, with Crowned Lapwing, Cattle Egret, and White-breasted Cormorant eggs the least. Based on feeding guilds, the mean ΣPOP concentrations increased from granivore, aquatic omnivore, scavenger, terrestrial insectivore, small aquatic predator, to large aquatic predator. Mean ΣPOP concentrations in eggs increased from terrestrial, to wetland, to aquatic habitat birds. Interesting patterns were observed with multivariate analyses. There were no significant regressions between egg size and any summed POP classes. ΣBFR concentrations were not correlated with ΣOCPs or ΣPCBs. Eggshell thinning of African Darter eggs was associated with p,p'-DDE and ΣPCB suggesting risk. Other metrics also suggest risk. Therefore, different species of terrestrial and aquatic birds from the same area acquire and deposit POPs in different proportions and quantities in their eggs. Trophic levels and habitat explain the overall patterns, but detailed differences were found, some of which we are unable to explain. Based on POPs residues in terrestrial, wetland, and aquatic bird eggs, different POPs classes behave differently in a shared large inland industrial area, complicating deductions about POPs and associated risks based on one or few species.


Assuntos
Poluentes Ambientais , Hidrocarbonetos Clorados , Bifenilos Policlorados , África Austral , Animais , Aves , Bovinos , Ecossistema , Monitoramento Ambiental , Poluentes Ambientais/análise , Hidrocarbonetos Clorados/análise , Bifenilos Policlorados/análise , África do Sul
3.
Ecotoxicology ; 27(3): 336-351, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29404865

RESUMO

Soweto and Lenasia, the most densely populated area of South Africa, is simultaneously a thriving metropolis, with a fair share of people still living in squalor conditions directly dependant on the natural resources. Because of industrialisation the populace and environment in this urban area are exposed to various pollutants. The aquatic environment was selected as a proxy to study the effect of industrial pollution in this area. The concentrations, source identification, and various environmental risks of polycyclic aromatic hydrocarbons (PAHs) were determined in sediments of the upper reaches of the Klip River. Composite sediment samples collected in low-flow conditions in 2013 and 2014 ranged from 270-5400 ng/g. The PAHs in this aquatic ecosystem were dominated by 4-ring congeners and could be attributed to combustion of organic fuels by chemical mass balance. Heavy traffic and industrial complexes in the northern part of the study area were responsible for the PAH fingerprints. Probable adverse effects such as toxicity to benthic biota were proven after comparison with international sediment quality guidelines (SQG) both survey years. Toxic equivalence quotients (TEQs) calculated for the sediments using fish potency factors (FPFs) were up to 30 times greater than the Canadian guideline for dioxin-like compounds, indicating high probability of carcinogenic effect to fish mediated through the aryl-hydrocarbon receptor. Finally, sediments in the area posed moderate to high ecological risk, which corroborates the other toxicity assessments. The advantage of investigating multiple risk endpoints, is the comprehensive results obtained that allows for a more realistic representation of the study area. Consequently more aspects are kept into account that results in better conclusions.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Animais , Sedimentos Geológicos/análise , Invertebrados/efeitos dos fármacos , Neoplasias/induzido quimicamente , Medição de Risco , Rios/química , África do Sul , Vertebrados
4.
Ecotoxicol Environ Saf ; 104: 393-402, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24703242

RESUMO

Repeated annual episodes of Nile crocodile deaths in two isolated areas of the Kruger National Park prompted the investigation of possible organohalogen pollutant involvement. Crocodile eggs were collected close to one of the mortality sites (Gorge) as well as from a crocodile farm (CF) as reference. ∑DDT was significantly higher in Gorge (450ng/g wm) than in CF eggs (85ng/g wet mass). Percentage DDT of ∑DDT was significantly higher in CF (14 per cent) than in Gorge eggs (5 per cent). Mean ∑DDT was almost 70 times higher than mean ∑PCB in Gorge eggs. HCB, ß-HCH, mirex, brominated flame retardants (BFRs), and perfluorinated compounds (PFCs) occurred at lower concentrations. We believe that the BFR and PFCs data represent the first published results for any crocodile egg. Thickening of the outer eggshell layer of Gorge eggs was significantly associated with higher concentrations of ∑DDT. Concentrations of ∑DDT and other pollutants were in the same range as eggs from elsewhere, where there were no mortalities. Concentrations of ∑DDT in eggs from healthy Australian crocodiles were of the same orders of magnitude as the current study, making it highly unlikely that the concentrations of pollutants measured in the present study would have caused or substantially contributed towards the mortalities observed. Concerns about reproduction and behaviour remain. As large predators, crocodilians are at the apex of the freshwater aquatic food web. More research is needed to guide measures to manage African freshwater systems so that it will also sustainably accommodate these large, long-lived animals.


Assuntos
Jacarés e Crocodilos , Compostos Orgânicos/análise , Poluentes Químicos da Água/análise , Zigoto/química , Animais , Austrália , África do Sul
5.
Mar Pollut Bull ; 202: 116371, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38657492

RESUMO

Comparative microplastic (MP) data for cephalopods between oceans is scarce. Our aim was to quantify, characterise, and compare MPs in gills, digestive gland, and mantle of chokka squid from the South Atlantic Ocean (SAO) and Indian Ocean (IO) off the coast of South Africa. South African squid had more MPs compared with other studies (means = 2.0 and 0.4 in SAO and IO squid mantle, respectively). Blue fibres were dominant. Identifiable MPs were polyethylene. Despite IO water having higher MP concentrations than the SAO, SAO squid had higher MP concentrations. Dilution by growth is the likely reason for the lower MP concentrations. Fibres were shorter in SAO than IO squid. However, we could not explain why fibre and mantle lengths from both oceans were positively correlated. Squid may not be the best indicator of marine MPs. The characteristics of MPs in squid can be used to track stocks and migrations.


Assuntos
Decapodiformes , Monitoramento Ambiental , Brânquias , Microplásticos , Poluentes Químicos da Água , Animais , Oceano Atlântico , Brânquias/metabolismo , Poluentes Químicos da Água/análise , Oceano Índico , Músculos/metabolismo , África do Sul , Sistema Digestório
6.
Environ Res ; 126: 240-53, 2013 10.
Artigo em Inglês | MEDLINE | ID: mdl-23850145

RESUMO

We investigated the presence, levels, relationships, and risks of HCHs, DDTs, chlordanes, mirex, PCBs, and brominated flame retardants (BFRs) in terrestrial and aquatic bird eggs from an area in South Africa where DDT is used for malaria control. We found one of the highest ΣDDT levels reported this century; 13,000 ng/g wm (wet mass) in Grey Heron eggs which exceeds critical levels for reproductive success (3000 ng/g wm) calculated for Brown Pelicans, with a no-effect level estimated at 500 ng/g wm. Even higher ΣDDT levels at 16,000 ng/g wm were found in House Sparrow eggs (possibly the highest ever recorded for sparrows), with a maximum of 24,400 ng/g wm. Significant eggshell thinning in Cattle Egrets (33% between thickest and thinnest) was associated with increased levels of p,p'-DDT and p,p'-DDE. There were indications of unknown use of DDT and lindane. Relative to DDT, PCBs and BFRs levels were quite low. Ordinated data showed that different terrestrial pollutant profiles converged to a homogenised aquatic profile. Converging profiles, high levels of DDT in heron and sparrow eggs, and thinning eggs shells, indicate risk and impacts at release, in the aquatic environment, and in between. If characteristic life-strategies of birds in warm areas (e.g. longer-lived and fewer eggs per clutch) increases the risk compared with similar birds living in colder regions when both experience the same environmental pollutant levels, then malaria control using DDT probably has more significant impacts on biota than previously realised. Therefore, risk assessment and modelling without hard data may miss crucial impacts and risks, as the chemical use patterns and ecologies in Africa and elsewhere may differ from the conditions and assumptions of existing risk assessment and modelling parameters. Consideration of other findings associated with DDT from the same area (intersex in fish and urogental birth defects in baby boys), together with the findings of this study (high levels of DDT in bird eggs, eggshell thinning in the Cattle Egrets, and the apparent absence of breeding piscivore birds in the sprayed area) are strongly suggestive of negative impacts from DDT spraying for Malaria control. Our data presents strong arguments for an expedited process of replacing DDT with sustainable methods.


Assuntos
Aves , Poluentes Ambientais/análise , Hidrocarbonetos Halogenados/análise , Óvulo/química , Animais , Análise Multivariada , África do Sul
7.
Environ Res ; 118: 53-64, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22694834

RESUMO

We report for the first time levels of persistent organic pollutants in marine bird eggs from an oceanic island in the Indian Ocean, the world's third largest ocean. Ten eggs each of the Common Noddy, also known as the Brown Noddy (Anous stolidus), and Sooty Tern (Sterna fuscata) were collected from Ile Cocos off the coast of the island of Rodrigues, located 560 km east of the island of Mauritius. ΣPCBs had the highest levels (2.2 and 2.6n g/g wm, wet mass; 20 and 19 ng/g lm, lipid mass) for common Noddy and Sooty Tern, respectively (and following), then ΣDDT (1.9 and 3.1 ng/g wm; 17 and 23 ng/g lm), and mirex (0.96 and 0.69 ng/g wm; 8.7 and 5.0 ng/gl m). ΣChlordanes (0.094 and 0.15 ng/g wm; 0.48 and 0.73 ng/g lm) and Σtoxaphenes (0.26 and 0.61 ng/g wm; 2.4 and 5.9 ng/g lm) are rare data for these compounds from this ocean. Brominated flame retardants were low (0.08 and 0.07 ng/g wm; 0.7 and 0.7 ng/g lm). Multivariate analyses indicated different contamination patterns in the prey items as Sooty Terns had significantly higher levels of mean Σchlordanes and Σtoxaphenes, as well as CB105, -108 and -157. p,p'-DDE had an association with thinner eggshells in the Sooty Tern. Although the contaminant levels were in all respects low, industrialisation, development on the periphery, commercial exploitation of the marine environment, and pollutants transferred over long distances by marine debris is likely to add to chemical pressure in this region. Monitoring changes in background levels of pollutants in remote regions will indicate such trends, and marine bird eggs from Rodrigues would be an excellent site.


Assuntos
Aves , Ovos/análise , Poluentes Ambientais/análise , Hidrocarbonetos Bromados/análise , Hidrocarbonetos Clorados/análise , Biologia Marinha , Animais , Geografia , Oceano Índico , Análise Multivariada , Especificidade da Espécie
8.
Reprod Domest Anim ; 47 Suppl 4: 327-32, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22827388

RESUMO

This study deals with disorders of sexual development in humans, wildlife and animals in an urban nature reserve (RNR) and a currently DDT-sprayed malarial area. High levels of oestrogenic chemical residues in water, sediment and tissue; skewed sex ratios; reduced biodiversity; gonadal malformations in sharptooth catfish and freshwater snails; intersex in catfish; and impaired spermatogenesis in catfish and striped mouse are of serious concern in the RNR. Persistent eggshell thinning in African darter eggs, intersex in male Mozambican tilapia, follicular atresia in females and impaired spermatogenesis in males following laboratory exposure of parent fish to environmentally relevant DDT and DDE concentrations, and abnormalities in freshwater snails were found in the DDT-sprayed area. Human studies related to DDT exposure indicated impaired semen quality, a weak association with sperm chromatin defects and higher risks for external urogenital birth defects in those who were born to mothers whose houses were sprayed and those who were homemakers (stay at home mother) instead of being employed. These findings indicate that diseases of sexual development occurred in both human and wildlife populations exposed to environmental endocrine disruptor chemicals in South Africa. The chemical mixtures, possibly related to disorders of sexual differentiation (DSD), were very different between the two. However, DSD occurred concurrently in the malarial area, possibly indicating that humans and wildlife shared exposures. Moreover, it emphasizes the importance of suspecting disease in the other when disease is found in either human or wildlife populations.


Assuntos
Animais Selvagens , DDT/toxicidade , Transtornos do Desenvolvimento Sexual/induzido quimicamente , Poluentes Ambientais/toxicidade , Inseticidas/toxicidade , Animais , Antílopes , Doenças das Aves/induzido quimicamente , Doenças das Aves/epidemiologia , Aves , Conservação de Recursos Energéticos , Transtornos do Desenvolvimento Sexual/epidemiologia , Feminino , Doenças dos Peixes/induzido quimicamente , Doenças dos Peixes/epidemiologia , Peixes , Humanos , Masculino , Óvulo/efeitos dos fármacos , África do Sul/epidemiologia , Anormalidades Urogenitais/induzido quimicamente , Anormalidades Urogenitais/epidemiologia , Anormalidades Urogenitais/veterinária , Poluição da Água/efeitos adversos
9.
Mar Pollut Bull ; 185(Pt B): 114345, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36410201

RESUMO

Elevated metal concentrations can become harmful to marine organisms and to humans that consume them. Metal concentrations at multiple sites around Algoa Bay, South Africa, were last investigated in the 1980s. We collected wild brown mussels (Perna perna) from seven sites around Algoa Bay, and quantified metallic elements using ICPMS. Metallic element concentrations differed significantly among the sampling sites and correlated with pollution sources at specific sites. The concentration of Pb in mussels at one site slightly exceeded South African limits. Based on the South African estimated daily intake, the target hazard quotient, and South African metal limits, mussels from Algoa Bay are safe for human consumption, except possibly from one site. However, combined with data on bisphenols and benzophenone UV filters in P. perna from the same sites, we suggest a possible health concern to consumers.


Assuntos
Poluentes Ambientais , Perna (Organismo) , Humanos , Animais , Baías , Metais , Alimentos Marinhos
10.
Sci Total Environ ; 806(Pt 2): 150346, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34601177

RESUMO

South Africa has the highest number of people living with the human immunodeficiency virus (HIV). High usage of HIV-antiretroviral drugs (ARVs) for the treatment of the acquired immunodeficiency syndrome (AIDS) leads to the presence of ARVs in the environment. Wastewater is a major contributor of pharmaceuticals in surface and drinking water as wastewater treatment plants (WWTPs) are not designed to remove these compounds. Pharmaceuticals in the environment pose risks and the effects of ARVs on non-target organisms are largely unknown. The concentrations of ARVs in surface water upstream and downstream from WWTPs in rivers were determined. The samples were extracted by solid-phase extraction and analysed by using liquid chromatography coupled with a quadrupole time-of-flight mass spectrometer. Five ARVs were quantified, mostly in downstream samples of the WWTPs, indicating wastewater as a source of ARVs, but this was not apparent in all cases. Nevirapine, lopinavir, and efavirenz were frequently detected; the highest concentrations being lopinavir and efavirenz at 38 µg/L and 24 µg/L, respectively. Aquatic ecosystems are at risk due to the constant input of pharmaceuticals that include large amounts of everyday use and the release of ARVs. This study highlights the potential of increased water pollution worldwide should more people consume increased quantities of pharmaceuticals.


Assuntos
Infecções por HIV , Preparações Farmacêuticas , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , África do Sul , Águas Residuárias/análise , Água , Poluentes Químicos da Água/análise
11.
Environ Toxicol Chem ; 40(6): 1726-1739, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33646628

RESUMO

We explored metal concentrations in wasps from 4 sites near Harare, Zimbabwe, on a 106 km west-east transect. We found elevated concentrations at 2 presumed-polluted sites (a platinum [Pt] mine and a known polluted lake) located near a metal-enriched geological feature (the Great Dyke). A site in urban Harare and a nature reserve served as reference. Only wasps from the 2 presumed-polluted sites had quantifiable Pt. For Cr, Ni, Mg, Se, Fe, Mn, and V, we report the highest concentrations in wasps yet published. Wasps from the presumed-polluted sites had significantly higher concentrations of most metals when compared with wasps from the reference sites, suggesting pollution as a source. Geology, however, differs between the sites. It is probable, therefore, that both geology and pollution contributed to the differences in metal concentrations. Because of its long and narrow dimensions (550 km long and 4-11 km wide), the Great Dyke offers opportunities for comparative studies. Because wasps form a complex part of the food web and ecology, studies on the transfer of metals to wasps' predators are needed, especially given that some birds specialize in feeding on hymenopterans. The rich diversity of wasps (>145 000 species worldwide) occupying multiple different trophic levels is a good indicator, and wasps have a rich potential to join other invertebrates as terrestrial indicators. Environ Toxicol Chem 2021;40:1726-1739. © 2021 SETAC.


Assuntos
Metais Pesados , Vespas , Animais , Monitoramento Ambiental/métodos , Invertebrados , Metais , Metais Pesados/análise , Zimbábue
12.
Chemosphere ; 262: 127716, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32799137

RESUMO

For the first time the occurrence of 25 organic micropollutants (OMPs) including; 11 personal care products (PCPs), six phthalate ester plasticizers (PEPs) and eight organophosphorus flame retardants (OPFRs) was investigated in 72 water samples obtained from five bays in the Uganda sector of Lake Victoria. In addition, an assessment of the potential ecotoxic risk of the target OMPs to aquatic organisms was conducted. Water samples were analyzed for the target OMPs using gas chromatography coupled with mass spectrometry (GC/MS). All the target PCPs were found in all the water samples with the exception of musk ketone and 2,6-di-tert-butylphenol. Triclosan (89-1400 ng L-1), benzophenone (36-1300 ng L-1), and 4-methylbenzylidine camphor (21-1500 ng L-1) were the most predominant PCPs. All the six plasticizers were found in all the water samples with dibutyl phthalate (350-16 000 ng L-1), and bis-(2-ethylhexyl) phthalate (210-23 000 ng L-1) detected at the highest concentrations. Five OPFRs out of the eight targeted were found in all the water samples. Tricresyl phosphate (25-8100 ng L-1), tris-(2-chloroethyl) phosphate (24-6500 ng L-1) and triphenyl phosphate (54-4300 ng L-1) were the most dominant OPFRs. The highest concentrations of OMPs were recorded in Murchison and Thurston Bays, presumably due to industrial wastewater effluents from the highly industrialized localities of the two Bays. Ecotoxicological risk assessment showed that PCPs (triclosan, musk ketone, and 4-MBC), plasticizers (dibutyl phthalate, bis-(2-ethylhexyl) adipate and bis-(2-ethylhexyl) phthalate) and OPFRs (tricresyl phosphate, triphenyl phosphate and tris-(2-chloroethyl) phosphate) pose a high ecotoxic risk to lives of aquatic organisms (risk quotients, RQ > 1).


Assuntos
Cosméticos/análise , Retardadores de Chama/análise , Lagos/análise , Compostos Organofosforados/análise , Plastificantes/análise , Poluentes Químicos da Água/análise , Animais , Cosméticos/toxicidade , Ecotoxicologia/métodos , Retardadores de Chama/toxicidade , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Organofosforados/toxicidade , Plastificantes/toxicidade , Medição de Risco , Análise Espaço-Temporal , Uganda , Águas Residuárias/química , Poluentes Químicos da Água/toxicidade
13.
Sci Total Environ ; 771: 145348, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33540163

RESUMO

We report the concentrations of persistent organic pollutants (POPs) in seabird eggs from St. Brandon's Atoll, a tropical island system in the western Indian Ocean. Ten eggs each of sooty terns (Onychoprion fuscatus), fairy terns (Gygis alba), and common noddies (Anous stolidus) were collected from the atoll. For a terrestrial reference, we analysed three feral chicken (Gallus gallus domesticus) eggs from the same location. Sooty tern eggs contained the highest mean concentrations of three chemical classes: Æ©CHL3 (0.21 ng/g wm; wet mass), Æ©PCB10 (1.5 ng/g wm), and Æ©PBDE6 (1.1 ng/g wm). Fairy tern eggs contained the highest mean concentrations of HCB (0.68 ng/g wm) and Æ©CHB5 (0.83 ng/g wm). The chicken eggs contained the highest mean concentrations of Æ©DDT3 (2.6 ng/g wm), while common noddy eggs contained the highest mean concentrations of Æ©HCH2 (0.5 ng/g wm). We surmise that the differences in chemical composition between species reflect different pollutant compositions in prey from the bird's different foraging ranges. The sooty terns foraging offshore contained higher POPs concentrations than the nearshore-foraging common noddies. Fairy tern eggs contained intermediate concentrations, commensurate with their intermediate foraging. Inter-island differences in contaminant concentrations were seen between eggs of the common noddies from St. Brandon's Atoll and Rodrigues Island, 520 km to the south-east. Concentrations of contaminants found in this study were lower than values quantified by other studies, making St. Brandon's Atoll an ideal reference site to monitor background concentrations of POPs in the tropical Indian Ocean.


Assuntos
Poluentes Ambientais , Poluentes Orgânicos Persistentes , Animais , Aves , Monitoramento Ambiental , Poluentes Ambientais/análise , Oceano Índico , Ilhas
14.
Chemosphere ; 264(Pt 1): 128368, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33007566

RESUMO

Mass Nile crocodile (Crocodylus niloticus) deaths in Africa's premier conservation area, the Kruger National Park (KNP), prompted numerous studies to determine possible causes of the sudden die-offs. The majority highlighted the involvement of the anthropocene to crocodile mass mortalities. One of the potential causative agents was identified as legacy compounds such as organochlorine pesticides (OCPs) present in the various aquatic ecosystems of the KNP. Thus, this study aimed to quantify OCP levels in wild crocodiles from the aquatic systems associated with the KNP. As part of a larger study, muscle tissue samples were collected from tails of 12 wild crocodiles. Results indicated that eight of the 19 OCPs analysed for were quantifiable. These included DDTs (2130-167968 ng/g lw), chlordanes (BD - 7583 ng/g lw) and cyclodeines (BD - 872 ng/g lw). Measured concentrations indicated spatial- and sex-related differences in accumulation patterns. DDT and its metabolites, paricularly p,p'-DDE accumulated to the highest concentrations of the OCP groups. Levels of the different groups of OCPs were the highest recorded in recent history from any crocodilian tissue. The different measured OCP residues were between 2.5 and 120 times higher than levels reported in literature, depending on the compound. These results are of ecotoxicological significance and have several management implications. In view of individuals being sampled from a conservation area it emphasizes the fact that pollutants know no boundaries and that premier conservation areas such as the world renowned KNP may be some of the most contaminated areas of the world.


Assuntos
Jacarés e Crocodilos , Hidrocarbonetos Clorados , Praguicidas , Poluentes Químicos da Água , Animais , Ecossistema , Monitoramento Ambiental , Humanos , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Poluentes Químicos da Água/análise
15.
Chemosphere ; 267: 129316, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33352370

RESUMO

Persistent halogenated compounds (PHC) are of concern for human and environmental health. Persistent Organic Pollutants (POPs) are regulated by international treaties, but alternative compounds such as novel brominated flame retardants (NBFRs) and Dechlorane Plus (DP) are not-yet they are increasingly used. There are no data on PHCs in coral reef biota from tropical islands in the western Indian Ocean (WIO). For this assessment, three hard coral genera, two soft coral genera, and ember parrotfish (Scarus rubroviolaceus) were collected from the remote Rodrigues, Agalega, and St. Brandon's Atoll (Republic of Mauritius) in the Mascarene Basin of the WIO. Five compounds - Pentabromotoluene (PBT), γ-HCH, p,p'-DDE, HCB, and BDE-47- were quantifiable in all samples. Hard coral consistently contained the lowest concentrations of PHCs, except for NBFRs. The presence of BDE-47 suggests long-range aerial transport. We quantified DP, currently a candidate POP, in coral reef biota. PBT was measured in all samples also suggests long-range transport. Because the hard coral, soft coral, and fish had differing concentrations and patterns of PHCs, future surveys should stratify sampling accordingly. Agalega and St. Brandon's Atoll can be considered as locations to monitor changes in background concentrations of pollutants due to their remoteness.


Assuntos
Antozoários , Retardadores de Chama , Animais , Recifes de Corais , Monitoramento Ambiental , Retardadores de Chama/análise , Éteres Difenil Halogenados/análise , Humanos , Oceano Índico , Ilhas
16.
Chemosphere ; 239: 124784, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31520976

RESUMO

Little knowledge exists on the state of metal contamination in corals from the Western Indian Ocean (WIO). Fragments of four soft and five hard coral genera were collected from five sites in the WIO- Sodwana Bay and Aliwal Shoal from South Africa, and Agalega, Rodrigues, and St. Brandon's Rock from the Mascarene Basin. Fragments were analysed for 31 metallic elements using inductively coupled plasma mass spectrometry. Corals from the WIO contained lower concentrations of most metals than corals from the Red Sea. South African corals contained higher concentrations of most of the metallic elements than the Mascarene corals. Sinularia was the coral with the most elements at the highest mean concentrations. A very high concentration of Ni was found in Sinularia (1300 mg/kg dm) from Sodwana Bay. Corals from the Mascarene Islands, especially Agalega, had comparatively low concentrations and could serve as a benchmark for corals from other regions.


Assuntos
Antozoários/química , Metais/análise , Poluentes Químicos da Água/análise , Animais , Monitoramento Ambiental , Oceano Índico , Ilhas do Oceano Índico , África do Sul
17.
Chemosphere ; 239: 124642, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31521936

RESUMO

The occurrence of 24 pharmaceuticals (including 15 antibiotics, three analgesic/anti-inflammatory drugs, three anti-epileptic/antidepressant drugs, two beta blockers, and one lipid regulator) was investigated in 75 water samples collected from four bays in the Ugandan part of Lake Victoria. In addition, the potential environmental risk of the target pharmaceutical compounds to aquatic organisms in the aquatic ecosystem of Lake Victoria was assessed. Water samples were extracted using solid phase extraction and analyzed for pharmaceuticals using high-performance liquid chromatography coupled with triple quadrupole mass spectrometry (LC/MS/MS). Eighteen of the 24 pharmaceuticals occurred at quantifiable concentrations. Sulfamethoxazole (1-5600 ng L-1), trimethoprim (1-89 ng L-1), tetracycline (3-70 ng L-1), sulfacetamide (1-13 ng L-1), and ibuprofen (6-780 ng L-1) occurred at quantifiable concentrations in all water samples. Sulfamethazine (2-50 ng L-1), erythromycin (10-66 ng L-1), diclofenac (2-160 ng L-1), and carbamazepine (5-72 ng L-1) were only quantifiable in water samples from Murchison Bay. The highest concentrations of pharmaceuticals were found in Murchison Bay, the main recipient of sewage effluents, industrial and municipal waste from Kampala city via the Nakivubo channel. Ecotoxicological risk assessment showed that sulfamethoxazole, oxytetracycline, erythromycin, and diclofenac pose a high toxic risk to aquatic organisms in the lake, while ciprofloxacin, norfloxacin, and ibuprofen pose a medium risk. This study is the first of its kind to report the levels and ecotoxic risks of pharmaceutical compounds in Lake Victoria waters, of Uganda, and East Africa as a whole.


Assuntos
Monitoramento Ambiental/métodos , Lagos/química , Preparações Farmacêuticas/análise , Esgotos/química , Poluentes Químicos da Água/análise , Antagonistas Adrenérgicos beta/análise , Antibacterianos/análise , Anti-Inflamatórios não Esteroides/análise , Organismos Aquáticos/efeitos dos fármacos , Cromatografia Líquida , Cidades , Diclofenaco/análise , Ecossistema , Ecotoxicologia , Medição de Risco , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Uganda
18.
J Agric Food Chem ; 68(22): 6084-6091, 2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32378893

RESUMO

Halogenated natural products (HNPs) and persistent organic pollutants (POPs) were quantified in South African sardines (Sardinops sagax) from one site in the South Atlantic Ocean and one in the Indian Ocean. At both sites, HNPs [2,3,3',4,4',5,5'-heptachloro-1'-methyl-1,2'-bipyrrole (Q1), mixed halogenated compound 1 (MHC-1), 2,4,6-tribromoanisole (2,4,6-TBA), 2'-MeO-BDE 68 (BC-2), and 6-MeO-BDE 47 (BC-3)] were 1 order of magnitude higher concentrated than anthropogenic POPs [mainly polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT), ∼3 ng/g lipids]. MHC-1 and Q1 were the major HNPs in the samples from both sites, contributing with up to 49 and 52 ng/g lipids, respectively. The same 1,1-dichloro-2,2-bis(4-chlorophenyl)ethane (p,p'-DDE)/PCB ratio suggested that the major POPs were evenly distributed at both sites. Different ratios of Q1/MHC-1 in the samples from the Indian (∼2:1) and South Atlantic (∼1:1) Oceans indicated that the occurrence of HNPs in seafood is difficult to predict and should be investigated more in detail. The PCB levels in sardines were found to pose no risk to human consumers, whereas HNPs could not be evaluated because of the lack of toxicological data.


Assuntos
Peixes/metabolismo , Contaminação de Alimentos/análise , Hidrocarbonetos Halogenados/análise , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Animais , Oceano Atlântico , Hidrocarbonetos Halogenados/metabolismo , Oceano Índico , Poluentes Químicos da Água/metabolismo
19.
Mar Pollut Bull ; 154: 111061, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32174506

RESUMO

Per- and polyfluoroalkyl substances (PFAS) are anthropogenic fluorinated compounds of concern for human and environmental health. There is no data on PFAS concentrations in marine bird eggs from the Western Indian Ocean. We analysed eight PFAS in eggs of fairy terns (Gygis alba), sooty terns (Onychoprion fuscatus), and common noddies (Anous stolidus) from St. Brandon's Atoll. Fairy tern eggs contained the highest concentrations, followed by sooty terns and common noddies. Perfluoroundecanoic acid (PFUdA) had the highest mean concentration (2.3 ng/g wm), followed by perfluorooctane sulfonic acid (PFOS) (2.0 ng/g wm), and perfluorononanoic acid (PFNA) (0.93 ng/g wm) in fairy tern eggs. Concentrations of all PFAS were lower than values found in literature. PFOS and PFOA concentrations were three orders of magnitude lower than toxicity reference values and levels of lowest-observed-adverse-effect-level concentrations. Eggs from St. Brandon's would be useful to monitor background changes on a regional and perhaps global scale.


Assuntos
Ácidos Alcanossulfônicos , Charadriiformes , Monitoramento Ambiental , Poluentes Ambientais , Fluorocarbonos , Animais , Ovos , Humanos , Oceano Índico
20.
Mar Environ Res ; 156: 104916, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32174336

RESUMO

Shallow shipwrecks, can have severe ecological and toxicological impacts on coral atolls. In 2012, a tuna longliner ran aground on the reef crest of St Brandon's Atoll, Mauritius, broke up into three pieces which was moved by currents and storms into the lagoon. In the months following the grounding, the coral around the wreck became dead and black. Down-current from the wreck, a dense bloom of filamentous algae (Ulva sp.) attached to coral occurred. To determine the ecological effects of the wreck on the system, the marine biota around the wreck, in the algal bloom, and fish reference zones were counted in 2014. Metal concentrations in reference and affected coral was determined using inductively coupled plasma mass spectrometry (ICP/MS). A pronounced difference was seen in the metal concentration pattern between coral from the wreck- and algal zones, and the coral reference zone. While the wreck zone contained the highest abundance of fish, the fish reference zone had the highest species diversity but with fewer fish. We also counted eleven Critically Endangered hawksbill sea turtles Eretmochelys imbricata and significantly more sea cucumbers in the algal zone than the reference zones. The effects of shipwrecks on coral reefs must be considered a threat over periods of years and should be studied further.


Assuntos
Antozoários , Recifes de Corais , Navios , Animais , Biodiversidade , Quelantes/análise , Monitoramento Ambiental , Peixes , Oceano Índico , Maurício , Ulva/crescimento & desenvolvimento , Poluentes Químicos da Água/análise
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