Bioaccumulation of DDT and other organochlorine pesticides in amphibians from two conservation areas within malaria risk regions of South Africa

Wolmarans, Nico J.; Bervoets, Lieven; Gerber, Ruan; Yohannes, Yared Beyene; Nakayama, Shouta M.M.; Ikenaka, Yoshinori; Ishizuka, Mayumi; Meire, Patrick; Smit, Nico J.; Wepener, Victor

doi:10.1016/j.chemosphere.2021.129956

Cited by 21 publications

(16 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…DNA damage can result in cancerforming changes (De Souza et al 2020;Hassan and Nemr 2020). Due to the high toxicity and ability of bioaccumulation, this group of pesticides is now largely banned in the world (Trang et al 2018), but in some parts such as Africa, it is still widely used (Wolmarans et al 2021). An important point limiting the production and use of organochlorinated pesticides was the drafting of the Stockholm Convention, which was adopted in 2009 (Stockholm Convention 2009).…”

Section: Pesticidesmentioning

confidence: 99%

Does aquatic sediment pollution result in contaminated food sources?

2021

View full text Add to dashboard Cite

The sediment pollution of the aquatic environment by waste due to anthropogenic activity is of an increasing concern. The contaminants coming from the aquatic environment can enter the aquatic food chain and accumulate in the tissues of fish and shellfish used for human consumption. The aim of this study was to sum up the current level of knowledge concerning the pollution of aquatic sediments and its transfer to aquatic foods as well as to indicate whether such contamination has the potential to affect the health and welfare of aquatic organisms as well as the quality and safety of the species intended for human consumption. Based on the results of scientific studies, the European Food Safety Authority, and the Rapid Alert System for Food and Feed, contamination of fish and seafood occurs predominantly through their diet and the levels of bioaccumulative contaminants are higher in fish which rank higher in the food chain. Contamination of aquatic habitats can not only significantly affect behavior, development, and welfare of aquatic organisms, but it can also affect the safety of fish and seafood for human consumption.

show abstract

Section: Pesticidesmentioning

confidence: 99%

Does aquatic sediment pollution result in contaminated food sources?

2021

View full text Add to dashboard Cite

show abstract

“…More generally, benthic invertebrate communities were driven by the concentrations of phosphates, sulphates, ammonium and organic matter and by substrate characteristics. can still drift over long distances, their bio-accumulation potential in aquatic organisms of conservation areas is correlated with their proximity to pollution sources (Wolmarans et al 2021). This means that river reaches further downstream from pollution sources should show a better ecological status.…”

Section: Introductionmentioning

confidence: 99%

“…However, to measure, protect and restore natural river integrity in the KNP, it would be more relevant to include multiple biological indicators of water quality (Rogers & Biggs 1999). Pollutants not only alter the chemistry of the water column but also persist in sediments (Gerber et al 2015) and within tissues of organisms (Gerber et al 2016;Seymore 2014;Wolmarans et al 2021). The consequences of altered environmental conditions have been found to translate into conspicuous modifications of the structure of bacteria, diatom, fish and insect communities in KNP water (Farrell et al 2019;Rasifudi et al 2018;Riddell et al 2019;Shikwambana et al 2021).…”

Section: Introductionmentioning

confidence: 99%

Diversity and distribution of benthic invertebrates dwelling rivers of the Kruger National Park, South Africa

Majdi

Necker

Fourie

et al. 2022

KOEDOE - African Protected Area Conservation and Science

View full text Add to dashboard Cite

Meiobenthos (or meiofauna) are microscopic invertebrates that inhabit biofilms and interstitial spaces in rivers. They are diverse and extremely abundant, and they perform essential ecological functions by linking microbial production to higher trophic levels (e.g. macrobenthic invertebrates and fishes). However, meiobenthic communities remain poorly studied in Africa. Here, we sampled meio- and macrobenthic invertebrate communities associated with biofilms and sediments across an upstream–downstream gradient along the Olifants, Sabie and Crocodile rivers flowing through the Kruger National Park (KNP). We expected to link differences in community structure to environmental gradients as those rivers show different degrees of anthropogenic stress as they enter the park. Both meio- and macrobenthic communities differed across rivers and also structured along an upstream–downstream gradient. The upstream sites, which were the closest to the park borders, consistently showed a lower diversity in all three rivers. There, the invasive snail Tarebia granifera strongly dominated (making up 73% – 87% of the macrobenthos), crowding hard substrates, while concomitantly the abundances of biofilm-dwelling meiobenthos like nematodes and rotifers were substantially reduced. Nevertheless, the diversity and evenness of communities then tended to increase as water flowed downstream through the park, suggesting a beneficial effect of protected river reaches on benthic invertebrate diversity. However, for the Crocodile River, which makes up the southern border of the park, this trend was less conspicuous, suggesting that this river may experience the greatest threats. More generally, benthic invertebrate communities were driven by the concentrations of phosphates, sulphates, ammonium and organic matter and by substrate characteristics.Conservation implications: Meiobenthic organisms are very abundant in KNP rivers and react to environmental gradients; thus, they should be more considered for bio-monitoring or conservation of comprehensive assemblages of animals. Interestingly, protected reaches tended to show a reduced dominance of the invasive T. granifera and a higher diversity of benthic invertebrates.

show abstract

“…Persistent Organic Pollutants (POPs), including organochlorine pesticides (OCPs), are resistant to biological, physical and chemical breakdown and as a result they have been banned world-wide through the Stockholm Convention in 2004 (Bouwman, 2004). Despite their banning, OCPs are still widely distributed in African ecosystems (Bouwman et al, 2014;Volschenk et al, 2019;Gerber et al, 2021). South Africa, a known user of OCPs in the agricultural sector (Wepener and Chapman, 2012), is the largest pesticide user south of the Sahara (Dabrowski et al, 2014).…”

Section: Introductionmentioning

confidence: 99%

“…The semi-volatile nature of OCPs results in their long-distance distribution to regions where there has been no direct use of these chemicals, e.g., ending up in coastal regions and remote river headwaters (Viljoen et al, 2016;Verhaert et al, 2017;Erasmus et al, 2020;Rose et al, 2020). This has led to a recent increase in studies addressing levels of OCPs in terrestrial and aquatic environments in South Africa (Thompson et al, 2017a;Volschenck et al, 2019;Gerber et al, 2021;Wolmarans et al, 2021). Due to trophic migration of compounds along the food web, the highest concentrations are usually reached at the top trophic level of a chain (Skaare et al, 2000), as seen in the study on trophic biomagnification of perfluorinated compounds in lichen, caribou and wolves (Müller et al, 2011).…”

Section: Introductionmentioning

confidence: 99%

First record of organochlorine pesticides in blood of wild and captive African leopards, Panthera pardus pardus (Linnaeus, 1758)

Smit

Wolmarans

et al. 2022

Front. Environ. Sci.

Self Cite

View full text Add to dashboard Cite

Compared to aquatic ecosystems, limited information exists on organochlorine accumulation in terrestrial ecosystems, and this is specifically true for terrestrial carnivores that have received limited attention in terms of studies on pollutant bioaccumulation. The African Leopard, Panthera pardus pardus (Linnaeus, 1758), is a popular focal species for research by ethologists and ecologists, but a noticeable knowledge gap exists with regards to toxicological aspects. To address this gap, the aim of this study was to determine baseline organochlorine pesticide (OCP) concentrations in blood of live wild and captive leopards in South Africa, and to explore the relationship between OCP levels and different conservation management strategies. Peripheral blood samples of seven captive and seven wild leopards, representing regular and melanistic individuals within the captive population, were collected while under sedation. The ΣOCP concentrations in blood serum were detected by means of GC-ECD. Statistical relationships among pesticide content in leopards from three geographical areas, different sexes, age groups and conservation status were examined. Captive leopards from this study had a slightly higher mean ΣOCP concentration (901 pg/ml) than wild leopards (768 pg/ml), and captive females had lower mean levels of ΣOCPs (797 pg/ml) than males (1,058 pg/ml). OCPs accumulated in the following order DDTs (27%) > HCHs (21%) > Heptachlors (15%) > CHLs (15%) > Drins (14%) > HCB (8%). Differences in OCP composition profiles of resampled captive individuals were also found. The sources of OCPs in the leopards can be attributed to the historic and current use of, e.g., DDT and HCHs, for malaria vector control and in insecticides/avicides in South Africa. For the captive leopards in this study the main source is possibly contaminated chicken that formed the major portion of their diet. This is the first report on OCP concentrations from leopards in Africa and highlights the need for this parameter to be considered in terms of the conservation management of healthy populations.

show abstract

Bioaccumulation of DDT and other organochlorine pesticides in amphibians from two conservation areas within malaria risk regions of South Africa

Cited by 21 publications

References 55 publications

Does aquatic sediment pollution result in contaminated food sources?

Does aquatic sediment pollution result in contaminated food sources?

Diversity and distribution of benthic invertebrates dwelling rivers of the Kruger National Park, South Africa

First record of organochlorine pesticides in blood of wild and captive African leopards, Panthera pardus pardus (Linnaeus, 1758)

Contact Info

Product

Resources

About