Table 4. Heavy metal** analysis and quantification in retrieved Ayurvedic samples.

Total samples, n = 42	Detected, n (%)	Minimum*	Maximum*	Mean*	Median*	SD
Aluminum	7 (16.6%)	18.560	418.400	130.380	68.850	142.2248
Arsenic	29 (69.1%)	0.0100	119.430	13.963	0.400	33.3589
Gold	13 (30.9%)	0.0400	1.440	0.662	0.480	0.5816
Mercury	25 (59.5%)	0.0100	8.010	0.673	0.190	1.5854
Manganese	20 (47.6%)	0.640	824.170	74.031	19.720	182.0916
Nickel	33 (78.6%)	0.200	73.290	7.461	2.150	14.2936
Lead	36 (85.7%)	0.0800	73.370	7.129	1.465	13.7904
Thallium	18 (42.8%)	0.0100	2.400	0.432	0.250	0.5826

^*values in mg/kg.

^**the level below which there is low risk for human ill health for arsenic is 0.07 mg/kg; the permissible tolerable weekly intake (PTWI) for mercury is 1.6 µg/kg body weight; PTWI of aluminum is 1 mg/kg of body weight; tolerable upper limit of manganese is 11 mg per day; tolerable daily intake for nickel is 5 µg/kg body weight; permissible daily oral exposure (PDE) of gold is 134 µg/kg; PDE of lead is 5 µg per day and of thallium is 8 µg per day.

From U. S. Department of Health and Human Services Food and Drug Administration, Center for Drug Evaluation and Research (CDER) and Center for Biologics Evaluation and Research (CBER), Guidance for Industry 2015 update. Retrieved from https://www.fda.gov/regulatory-information/search-fda-guidance-documents/q3d-elemental-impurities on 3/10/2019.