**4.1. Environmental impact**

CNSL may be a weak promoter of carcinogenesis but no mutagenic or carcinogenic activity has been reported [64]. Epidemiological studies suggested that CNSL may contribute to oral sub-mucous fibrosis [65]. In addition, its phenolic components exerted several biological activities, including antioxidative properties [66, 67], inhibition of acetyl cholinesterase and membrane perturbation [68, 69].

There is no direct evidence regarding the toxicity of CNSL or its major phenolic components. However, the effluent generated during the processing of the cashew nut could be considered potentially harmful to the environment due to its high phenol content. The hazardous effects of phenolic compounds have been extensively studied. According to [70], a concentration above 1 mg/L can affect aquatic life, while [71] recognizes deleterious effects at concentrations as low as 1 µg/mL.

As previously mentioned, data on the chemical composition of the cashew nut industry effluent are scarce, but preliminary analysis showed high phenol content due to the cardol, cardanol and anacardic acid of CNSL. The high toxicity observed for the isolated phe‐ nols, cardol and cardanol potentially contribute to the toxicity of the cashew nut industry effluent [72].
