The Moroccan olive oil industries generate a substantial amount of olive mill wastewater (OMW), causing a significant environmental issue. Consequently, its valorization represents a sustainable agroecological solution to the environmental problems caused by this uncontrolled discharge. In this...

This study investigated the chemical composition, antioxidant activity, and genotoxic potential of essential oils (EOs) obtained by hydrodistillation from aerial parts of four wild-growing Lamiaceae species in eastern Morocco: Spanish ziziphora (Ziziphora hispanica L.), felty germander (Teucrium polium L.), French lavender (Lavandula dentata L.), and topped lavender (Lavandula stoechas L.). Gas chromatography–mass spectrometry (GC-MS) analysis revealed eucalyptol (40.08%), thujopsene (11.25%), β-myrcene (15.82%), and fenchone (30.69%) as the major constituents in Z. hispanica, T. polium, L. dentata, and L. stoechas, respectively. Antioxidant capacity was evaluated using three complementary assays: 2,2-diphenyl-1-picrylhydrazyl radical scavenging, ferric reducing antioxidant power, and β-carotene bleaching. L. stoechas and L. dentata exhibited the strongest antioxidant activities, with IC₅₀ values ranging from 0.284 to 1.71 mg/mL across assays. Genotoxicity was assessed in rat leukocytes using the alkaline Comet assay at EO concentrations of 2.5, 5, and 10 µg/mL. All tested EOs induced statistically significant DNA damage compared to the negative control, though the extent varied by species and concentration; notably, L. stoechas at 2.5 µg/mL showed the lowest genotoxic impact. These findings highlight the dual potential of these EOs as natural antioxidants while underscoring the need for dose-dependent safety evaluation prior to therapeutic or industrial application. Given that DNA damage was detectable even at 2.5 µg/mL, a conservative practical recommendation is to keep EO levels below 2.5 µg/mL-equivalent in preliminary applications, pending further in vivo toxicology to establish NOAEL-based exposure limits.