First report on cyanotoxin (Mc-lr) removal from surface water by multi-soil-layering (msl) eco-technology: Preliminary results

Cyanobacteria blooms occur frequently in freshwaters around the world. Some can produce and release toxic compounds called cyanotoxins, which represent a danger to both the environment and human health. Microcystin-LR (MC-LR) is the most toxic variant reported all over the world. Conventional water treatment methods are expensive and require specialized personnel and equipment. Recently, a multi-soil-layering (MSL) system, a natural and low-cost technology, has been introduced as an attractive cost-effective, and environmentally friendly technology that is likely to be an alternative to conventional wastewater treatment methods. This study aims to evaluate, for the first time, the efficiency of MSL eco-technology to remove MC-LR on a laboratory scale using local materials. To this end, an MSL pilot plant was designed to treat distilled water contaminated with MC-LR. The pilot was composed of an alternation of permeable layers (pozzolan) and soil mixture layers (local sandy soil, sawdust, charcoal, and metallic iron on a dry weight ratio of 70, 10, 10, and 10%, respectively) arranged in a brick-layer-like pattern. MSL pilot was continuously fed with synthetic water containing distilled water contaminated with increasing concentrations of MC-LR (0.18–10 µg/L) at a hydraulic loading rate (HLR) of 200 L m−2 day−1. The early results showed MC-LR removal of above 99%. Based on these preliminary results, the multi-soil-layering eco-technology could be considered as a promising solution to treat water contaminated by MC-LR in order to produce quality water for irrigation or recreational activities. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.This research has received funding from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No 823860

Study of Seasonal variation and Index Based Assessment of Water Quality and Pollution in Semi-Arid Region of Morocco

Water resources quality assessment a basic requirement for ensuring its sustainability. Groundwater resources being restricted under the earth crust are at high risk of being polluted as compared to rivers which flow continuously. This study evaluated groundwater quality in Mohammedia prefecture, Morocco in terms of physicochemical parameters and seasonal variation. The physicochemical parameters analysed were Temperature, pH, EC, TDS, Na+, Ca2+, K+, NH4+, NO2-, NO3-, PO43-, SO42. Seasonal variation was evaluated for winter and spring seasons. The water quality was assessed in terms of overall water and Pollution index. Cation/anion ratio to TDS revealed evaporation and rock weathering dominance. Based on Pollution index, water quality of 88% samples was in excellent to good category in winter season. The pollution index during winter season was <1 for all sample locations. In Spring PI was >1 only at Location P1 which was attributed to NO2-. In Spring season 78% water samples were in Good to excellent category. The decrease in concentration during spring season was attributed to lack of soil-water interaction with reduced infiltration rate. The increase in concentration of parameters was attributed to anthropogenic activities. Further studies are needed to establish relationship between infiltration rate and pollutants concentration with respect to precipitation during monsoon season. Even though water quality in majority areas was fit for consumption and domestic use still further analysis should be carried out in terms of heavy metals and other emerging pollutants