The use of polluted water to irrigate is an increasing problem in the developing world. Lebanon is a case in point, with heavily polluted irrigation waters, particularly in the Litani River Basin. This study evaluated the potential health risks of irrigating vegetables (radishes, parsley, onions, and lettuce) using three water sources (groundwater, river water, and treated wastewater) and three irrigation methods (drip, sprinkler, and surface) over two growing seasons in 2019 and 2020. Water, crop, and soil samples were analyzed for physicochemical parameters, pathogens, and metals (Cu, Cd, Ni, Cr, and Zn). In addition, the bioaccumulation factor, estimated dietary intakes, health risk index, and target hazard quotients were calculated to assess the health risk associated with metal contamination. The study showed that, for water with less than 2 log E. coli CFU/100 mL, no pathogens (Escherichia coli, salmonella, parasite eggs) were detected in irrigated vegetables, irrespective of the irrigation method. With over 2 log E. coli CFU/100 mL in the water, 8.33% of the sprinkler-and surface-irrigated vegetables, and 2.78% of the drip-irrigated root crops (radishes and onions), showed some degree of parasitic contamination. E. coli appeared only on root crops when irrigated with water having over 3 log CFU/100 mL. The concentrations of most metals were significantly lower than the safe limits of the FAO/WHO of the Food Standards Programme Codex, except for zinc and chromium. The trends in the bioaccumulation factor and the estimated dietary intakes of metals were in the order of Cu < Cd < Ni < Cr < Zn. The target hazard quotient values for all metals were lower than 1.0. Under trial conditions, the adoption of drip irrigation with water with less than 3 log E. coli CFU/100 mL proved to be safe, even for vegetables consumed raw, except for root crops such as onions and radishes that should not be irrigated with water having over 2 log E. coli CFU/100 mL. Treated wastewater had no adverse effect on vegetable quality compared to vegetables irrigated with other water sources. These results support efforts to update the Lebanese standards for water reuse in agriculture; standards proposed in 2011 by the FAO, and currently being reviewed by the Lebanese Institution of Standards. This research will inform a sustainable water management policy aimed at protecting the Litani River watershed by monitoring water quality.

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A field experiment was carried out in Lebanon to assess the agronomic and essential oil characteristics of cannabis as affected by sowing date and irrigation practice. The experiment consisted of a split-plot design with the water regime being the main factor (Iopt-irrigated when the readily available soil water is depleted; I50- receiving 50% of the irrigation amounts in Iopt treatments) and sowing date as the sub-plot factor (mid-April; end of April; mid-May). Biometric and seed quality parameters of the cannabis crop were determined. The essential oils (EO) of the inflorescence were subjected to a multivariate analysis such as principal component analysis (PCA) and hierarchical cluster analysis (HCA). The obtained results revealed that the aboveground fresh biomass, the dry matter, and the plant height were 55.08%, 59.62%, and 43.11% higher in Iopt than in I50, respectively. However, the EO content was neither statistically affected by the irrigation regime nor by the sowing date. Under early sowing, both the water-use efficiency (WUE) for biomass and the EO production reached their highest values. All treatments presented a similar seed composition except that the crude fat and crude protein content were more elevated in Iopt than in I50 treatments. The main extracted essential oils in cannabis inflorescence corresponded to twenty-six identified compounds representing 79.34% of the monoterpenes and 81.25% of the sesquiterpenes. The monoterpenes were highly correlated with the irrigation treatment and early-April sowing while the sesquiterpenes were better enhanced under I50 and end of April to mid-May sowing. The study reveals that agronomic practices lead to differential responses of pharmacologically useful plant compounds for improved health benefits. Further research is required to clarify the potential for cannabis cultivation in Lebanon.

Aflatoxin B1 is a carcinogenic mycotoxin that frequently contaminates crops worldwide. Current research indicates that the use of natural extracts to combat mycotoxin contamination may represent an eco-friendly, sustainable strategy to ensure food safety. Although Cannabis sativa L. has long been known for its psychoactive cannabinoids, it is also rich in many other bioactive molecules. This study examines extracts from various organs of Cannabis sativa L. to determine their ability to limit aflatoxin production and growth of Aspergillus flavus. The results indicate that flower extract is most effective for limiting the synthesis of aflatoxin B1, leading to an almost-complete inhibition of toxin production at a concentration of 0.225 milligrams dry matter per gram of culture medium. Since flower extract is rich in phenolic compounds, its total antioxidant ability and radical-scavenging capacity are determined. Compared with other anti-aflatoxigenic extracts, the anti-oxidative potential of Cannabis sativa L. flower extract appears moderate, suggesting that its anti-mycotoxin effect may be related to other bioactive compounds.