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The presence of pharmaceutical compounds in the whole environment is a growing concern. These compounds might be present in the effluents of wastewater treatment plants and, hence, irrigation with treated sewage may be a source of groundwater pollution. The volcanic aquifer that lies NE of Gran Canaria (Spain) was studied to address the relationship of the occurrence of pharmaceutical compounds and a golf course that has been irrigated with regenerated water since 1973. Of the 14 analyzed groundwater samples, five wells were chosen to perform annual monitoring. Irrigation water and soil leachate were also evaluated. The target analytes were atenolol, metamizole, fluoxetine, ibuprofen, nicotine, permethrin, caffeine, and their metabolite paraxanthine. The environmental risk is limited as the concentrations of the pharmaceuticals measured in the sampled wells were always below 60 ng·L−1 (lower than the detected caffeine and nicotine concentrations). Wide variations for the same wells were measured among sampling campaigns, and also among the different wells. The study points to the importance of sample conservation during transport and the need to perform analyses immediately, or to follow an in-situ extraction procedure to carry concentrated samples under better conditions. [ABSTRACT FROM AUTHOR]

Cape Verde, which has agricultural land that is mainly rainfed, will be severely affected by climate change due to increased drought conditions. Scarce water availability makes this country highly dependent on imports for its food supply, resulting in more than 80% food importation. Improving water use efficiency, implementing precision irrigation could help achieve sustainable use of water resources. Cereal production reusing treated water could contribute to strengthening resilience and adaptation to climate change in Cape Verde. Our pilot project demonstrates that the safe and profitable reuse of water produced by Cape Verde's water treatment plants is possible by avoiding water and plant contact using Subsurface Drip Irrigation (SDI), obtaining food yields between 10,000 and 7000 kg of cob/ha, with a water consumption of about 300 L/kg Dry-Matter and a Water-Use-Efficiency of about 3 g/L. These studies also showed that it is necessary to provide training to farmers and to conduct further studies to help solve present challenges. This project identif installation failures as water shortages can compromise farmers' profitability. To guarantee the sustainability of water reuse, it is also necessary to consider economic and social factors, including that all water that is not reused is poured, increasing environmental and sanitary risk and decreasing the possibility of recovering water treatment costs. [ABSTRACT FROM AUTHOR]

In the Canary Islands, there is a hydrological imbalance between water consumption and renewable water availability. To provide more water resources, reverse osmosis (RO) from seawater is used. As boron (B) contents in irrigation water higher than 0.7 mg/L may be dangerous for sensible plants, B concentration in RO water (ROW) may be one of the key factors of irrigation sustainability. Some orchards have been studied after they have used drip irrigation using different water qualities for 30 years. B in water, soils, and banana leaves was determined to check the sustainability of ROW irrigation. When irrigating with ROW, in which B concentration varies between 1.0 and 1.4 mgB/L, B content in banana soils seems to be stabilized at 5–7 mg/kg, and no toxicity has been observed in banana leaves. The proper water and soil management used by the local farmers probably prevent the accumulation of higher B levels in soils. Considering water consumption of 9000 m3∙ha−1∙year−1, 8−11 kgB∙ha−1∙year−1 is applied to the soil. The banana plant removes approximately 1 kgB∙ha−1∙year−1; therefore, only 10% of the total B added gets exported. This raises the following question: is it better to use membranes that are able to reduce B in ROW, increase the leaching fraction, or blend water? [ABSTRACT FROM AUTHOR]