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dc.contributor.authorViljoen, Ignatius Michaelen_US
dc.descriptionThesis (M.Sc (Environmental Science))--North-West University, Potchefstroom Campus, 2011.
dc.description.abstractWith parts of SA in a malaria endemic area, a preventative way of fighting malaria is with the use of pesticides such as 1,1,1–Trichloro–2,2–bis(pclorophenyl) ethane, also known as DDT. DDT is listed under the persistent organic pollutants (POPs) and considered an endocrine disruptive compound (EDC) under the Stockholm Convention. SA registered an exemption to use DDT as means to fight malaria. DDT and its isomers are, however, known EDCs. Combined with their ability to persist in the environment while not being target specific motivates further studies into possible detrimental effects. The present study aimed to establish if ED was present by comparing the male reproductive organs from snails from an area currently sprayed with DDT (for malaria control) to an area not sprayed with DDT in the Limpopo Province. A possible endpoint (the penis sheath/preputium length ratio or PSPLR) was identified for the freshwater snail Bulinus tropicus. B. tropicus and sediment samples were collected from DDT–sprayed and nonsprayed areas located close together. The snails were dissected and various morphometric parameters measured. Sediments from the sites where the snails were collected were analysed for DDT using GC–MS. Statistical analysis showed significant differences in PSPLR (and therefore possible ED) between snails from the two areas. The difference in PSPLR values was mainly due to a relatively shorter preputium for the snails from the DDT–sprayed area. Even though the sediment samples showed that DDT was present in most of the DDT–sprayed sites and not in the non–DDT sprayed sites, causality of the possible ED could not be established from this field study. This study indicated the possibility of using the PSPLR as endpoint for ED. Recommendations are made for further development of the PSPLR and B. tropicus as biological indicators for endocrine disruption, but causality must first be established.en_US
dc.publisherNorth-West University
dc.subjectPersistent organic pollutantsen_US
dc.subjectEndocrine disruptionen_US
dc.subjectEndocrine systemen_US
dc.subjectLimpopo Provinceen_US
dc.subjectPenis sheathen_US
dc.subjectMalaria controlen_US
dc.subjectPersisterende organiese besoedelstowween_US
dc.subjectEndokriene versteuringen_US
dc.subjectEndokriene stelselen_US
dc.subjectLimpopo Provinsieen_US
dc.subjectMorfometriese afmetingsen_US
dc.subjectPenis skedeen_US
dc.subjectMalaria beheeren_US
dc.titlePossible endocrine disruption in molluscs from the Limpopo Provinceen

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  • ETD@PUK [6956]
    This collection contains the original digitized versions of research conducted at the North-West University (Potchefstroom Campus)

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