Pesticides in South African fresh waters

  • TM Ansara-Ross
  • V Wepener
  • PJ van den Brink
  • MJ Ross

Abstract

Public concern has recently escalated over pesticide contamination of South African aquatic ecosystems. This review of published literature on the occurrence of pesticides within South African freshwater systems indicates that fewer than 50 studies of selected pesticides have been undertaken, with emphasis being on organochlorines. Extensive historical usage has led to the widespread persistence of selected organochlorines. Few studies have established linkages between pesticides, exposure pathways, environmental concentrations and the monitoring of toxicological effects on non-target organisms. Emphasis is now being placed on developing more field-relevant assessments, including microcosm and mesocosm studies, in situ bioassays and field studies. There are few data relating to the extent of exposure and effects of pesticides in South African aquatic environments, and thus further research is needed. Research should focus on multidisciplinary approaches that increase effective decisionmaking in data-poor circumstances. A pesticide risk assessment programme for aquatic ecosystems needs to be implemented in South Africa, which could feed into the National Toxicity Monitoring Programme. Preliminary risk assessment models should be used to detect pesticides posing possible or definite risks, whereafter more detailed chemical, toxicological and biological monitoring assessments should be performed if risks are predicted.

Keywords: aquatic ecosystems, pesticide monitoring, review, risk assessment

African Journal of Aquatic Science 2012, 37(1): 1–16

Author Biographies

TM Ansara-Ross
Centre for Aquatic Research, Department of Zoology, University of Johannesburg, Auckland Park, PO Box 524, Johannesburg 2006, South Africa
V Wepener
Centre for Aquatic Research, Department of Zoology, University of Johannesburg, Auckland Park, PO Box 524, Johannesburg 2006, South Africa
PJ van den Brink
Department of Aquatic Ecology and Water Quality Management, Wageningen University and Research Centre, PO Box 8080, 6700 AA Wageningen, The Netherlands; current address: Alterra, Wageningen University and Research Centre, PO Box 47, 6700 AA Wageningen, The Netherlands
MJ Ross
Centre for Aquatic Research, Department of Zoology, University of Johannesburg, Auckland Park, PO Box 524, Johannesburg 2006, South Africa
Section
Articles

Journal Identifiers


eISSN: 1727-9364
print ISSN: 1608-5914