When trying to find synonyms for the phrase "not injurious," several words and phrases come to mind. Some of them include non-harmful, non-toxic, safe, and benign. These terms all convey the message that something is not damaging or dangerous to one's health or well-being. Other potential synonyms might include words like innocuous, gentle, mild, or even therapeutic. Depending on the context in which the phrase is being used, some of these synonyms may be more appropriate than others. Overall, however, the overarching goal is to convey the message that something is not harmful or negative in any way, shape, or form.