“…Of the 56 included studies, 28 were characterized as observational and descriptive studies, out of which 20 studies used whole body[56], [66], [67], [68], [69], [70], [71], [72], [73], [74], [75], [76], [77], [78], [79], [80], [81], [82], [83], [84], 3 blood cells[85], [86], [87], 3 saliva[64], [88], [89], 1 blood plasma[90], and 1 breath[91] as systems of research. The details of these studies will be reported on in future publications.…”