Quantification of microcystin-producing microcystis in freshwater bodies in the Southern Mozambique using quantitative real time polymerase chain reaction

In the last decades, large number of reported cases of illnesses in Mozambique is related to drinking water. However, only a limited number of studies have focused on aquatic pollution in this country. Cyanobacterial blooms dominated by Microcystis sp are regularly identified in freshwater bodies in Mozambique. Microcystis is known to proliferate in freshwater bodies and produce microcystins which have adverse effects on animals and humans. The aim of this study was to quantify microcystinproducing Microcystis in three different freshwater bodies in Southern Mozambique. TaqMan based real time polymerase chain reaction (PCR) (Taq Nuclease Assay) was used to quantify populations of Microcystis in three aquatic ecosystems in Southern Mozambique. Total Microcystis spp  (microcystinproducing and non-producing strains) were quantified in the three selected study areas with the determination of the copy numbers of the phycocyanin (PC) operon. Microcystin-producing gene copy numbers were quantified using specific primer pair, amplifying the mcyB gene. Microcystis mcyB copy numbers varied from 4.2 x 106 to 1.6 x 109 gene copies /L in 2008, corresponding to 2.15 to 98.55% of total Microcystis, and from 9.6 x 107 to 4.5 x 109 gene copies /L in 2009, corresponding to 1.53 to 34.52% of total Microcystis. High copy numbers of mcyB occurred in Nhambavale Lake in June 2008, whereas in March 2009, high copy numbers of mcyB was observed in Chòkwé Irrigation Channels. Samples from Pequenos Libombos Dam had the lowest number of mcyB gene copies in both sampling periods. The findings of the present study show that microcystin-producing strains are common in Southern Mozambique, and that their absolute and relative numbers varies geographically and temporarily. The highest concentration of Microcystis sp. in the sampling areas occurred in samples collected in March 2009, which corresponds to the rain season with warm temperatures. To our knowledge, this is the first report of the quantification of microcystin-producing Microcystis in Mozambique using molecular techniques.Keywords: Microcystis sp, Taq nuclease assay, phycocyanin (PC), mcyB, MozambiqueAfrican Journal of Biotechnology Vol. 12(30), pp. 4850-485

Policy relevant Results from an Expert Elicitation on the Human Health Risks of Decabromodiphenyl ether (decaBDE) and Hexabromocyclododecane (HBCD)

Aim: Apply a recently developed expert elicitation procedure to evaluate the state of the current knowledge of the two brominated flame retardants (BFRs) most commonly used today; decabromo-diphenyl ether (decaBDE) and hexabromocyclododecane (HBCD) and their potential impact on human health in order to support policy considerations. This expert elicitation was organized by the HENVINET (Health and Environment Network) Consortium. Method: The HENVINET expert elicitation procedure that was used in the evaluations of decaBDE and HBCD is a rapid assessment tool aimed at highlighting areas of agreement and areas of disagreement on knowledge-related key issues for environment and health policy decision making. Results: The outcome of the expert consultation on BFRs was concrete expert advice for policy makers with specific priorities for further action made clear for both stakeholders and policy makers. The experts were not in agreement whether or not the knowledge currently available on decaBDE or HBCD is sufficient to justify policy actions, but most experts considered that enough data already exists to support a ban or restriction on the use of these compounds. All experts agreed on the necessity of more research on the compounds. Priority issues for further research were, among others: more studies on the extent of human exposure to the compounds. more studies on the fate and concentration in the human body of the compounds

Organochlorine contaminants in cormorant, darter, egret, and ibis eggs from South Africa

http://dx.doi.org/10.1016/j.chemosphere.2007.09.05

Polybrominated diphenyl ethers and HBCD in bird eggs of South Africa

http://dx.doi.org/10.1016/j.chemosphere.2008.03.02