Mounir Kassir

Synthetic dyes, such as methylene blue (MB), constitute a major category of environmental pollutants due to their toxicity, persistence, and resistance to standard treatment methods. In this study, Bacillus cereus BC WW Saida was isolated from the heavily polluted Saida dumpsite in Lebanon and evaluated for its MB degradation efficiency. The isolate was identified through whole-genome sequencing, which revealed the presence of key enzymatic systems involved in azo dye degradation. Under optimized conditions, the strain achieved 82% decolorization, as determined by optical density measurements using a microplate reader. The process was further examined using High-Performance Liquid Chromatography (HPLC), which revealed a significant reduction in the original dye peak and the emergence of new intermediate products. These findings suggest the strong biodegradation capability of B. cereus BC WW Saida isolated from contaminated environments and highlight its potential application in the eco-friendly treatment of azo dye-contaminated wastewater.

Laurus nobilis belongs to the family Lauraceae and is characterized by its evergreen nature. It is well known because of its traditional use in cooking and folk medicine. Many studies have been performed regarding its chemical composition and the pharmacological potential it exhibits. It has been reported to have antioxidant, antibacterial, antifungal, antiviral, biocidal, antidiabetic, antiulcerogenic, neuroprotective, analgesic, anti-inflammatory, and anticholinergic properties, making this plant of great clinical importance. The main chemical compounds that show bioactive properties in L. nobilis are terpenoids, phenolics, and fatty acids. The purpose of this review is to describe the main use of L. nobilis, notably of the leaves and fruits, and to relate their metabolite content with their pharmacological and toxicological properties.

Chronic dietary aluminum (Al) exposure can have various negative effects on health. The aim of our study is to (1) assess the contamination level of Al in infant formulas (n = 41) and baby food products (n = 76) available in the Lebanese market, and to (2) evaluate the margin of exposure of Al through the consumption of these foods among children under the age of five in Lebanon. Flame atomic absorption spectrometry (FAAS) was used to evaluate all of the samples. Al levels in all tested children’s food items were below the limit of detection. The highest Al level was detected in cornflakes (0.361 ± 0.049 mg/kg) and pureed foods (0.362 ± 0.079 mg/kg). Among infants aged 0–23 months, the average Al exposure due to the daily intake of infant formulas and baby foods was 0.01 and 0.0104 mg/kg BW/day for males and females, respectively. Babies aged 8–10 and 3–5 months had the highest and lowest levels of Al exposure, respectively. Additionally, the toxicological contribution of Al exposure determined for several age groups to a provisional tolerated weekly intake (PTWI) set by JECFA was <6% and <7% for males and females, respectively. The total Al exposure through the consumption of infant formulas and complementary foods among all ages in both males and females was below the values of weekly tolerable intakes (2 mg/kg/BW/W) set by JECFA. However, the values of hazard quotient (HQ) exceeded 1 in both male and female Lebanese infants. As a result, the risk of infants being exposed to Al in baby foods needs to be continuously considered.

This paper addresses the residual toxicity of waters after photocatalysis treatments. The initial waters contain 7 mg L^-1 of sulfaquinoxaline (SQX) which is a sulfonamide antibiotic generally recorded inside the water. The contaminated waters are treated by photocatalytic degradation process with bare titania and titania covered with polyaniline (PANI) conducting polymer. The degradation of SQX is conducted at different pH in order to find the optimal condition to obtain SQX concentration relatively equal to zero in the shortest amount of time. This occurs for PANI/TiO₂ at pH 12 and TiO₂ at pH 4. Toxicity assays (concentration of biomass, pigmentation tests, and cells counting) are undertaken on the microalgae Chlorella vulgaris in order to evaluate the residual toxicity of the 2 treated waters. The toxicity results highlight that the water treated by PANI/TiO₂ at pH 12 is the less toxic towards the algae cells. The water processed by bare titania at acidic pH displays unneglectable toxicity towards the algae cells which is larger than the toxicity of the original SQX solution.