4.3. Future directions
We have determined that cyanotoxin-producing species are present in water impoundments in both urban and rural environments; that cyanotoxins accumulate in both drinking and irrigation water as well as in the soil horizon; and that the mode of transportation and tank material correlate with toxin accumulation. Although a pilot study, the findings warrant more extensive research efforts to determine cyanobacterial and toxin bioaccumulation hot spots in the water treatment process from desalination to the tap. Specifically, samples should be taken of seawater abstracted and used in the desalination plant as well as brine that is disposed of and returned to the sea. Drinking water in water treatment plants, storage reservoirs and main water storage tanks in compounds should be consistently sampled and tested.
Sewage effluents and wastewater should also be sampled at point sources and all throughout their purification process. The resulting TSE is used in Qatar to irrigate plants in parks and landscaped corridors of highways. Analysis of this water along with that of groundwater well samples will allow us to accurately determine the cyanotoxin bioaccumulation potential in ornamental plants and in crops destined for human and animal consumption.
Finally, a more elaborate scheme that covers the whole geographical area and extends over a year will enable us to obtain a better resolved picture of the spatio-temporal and diurnal variation of toxin accumulation, when combined with microbial metagenomic analysis, water chemistry and environmental parameters will provide a better understanding of cyanobacterial abundance and the environmental factors that control it.
Collectively, elucidation of these missing links will help in taking appropriate actions to limit human exposure to cyanobacteria and cyanotoxins, and in making managerial decisions that best preserve and conserve this natural resource and to develop a sustainable local economy as is envisioned in the QNFSP 2008 and Qatar National Vision (QNV) 2030 (QGSDP, 2008 and QGSDP, 2011).