Document Type


Date of Award



College of Science, Engineering, and Technology (COSET)

Degree Name

MS in Environmental Toxicology

Committee Chairperson

Bobby L. Wilson

Committee Member 1

Mahmoud Saleh

Committee Member 2

Maruthi S.B. Bhaskar

Committee Member 3

Renard Thomas


• Arsenic, Cadmium, Lead, Mercury metal toxic concentrations Cannabis oil personal care products Inductively Coupled Plasma Mass Spectrometry (ICPMS) Marijuana and hemp Tetrahydrocannabinol (THC) and Cannabinoid, Cannabidiol (CBD) medicinal and recreational use


There has been a critical need to ensure products are of required standard and safe for use; therefore, the United States and other countries have been releasing laws and regulations to moderate the safety of medicinal and/ recreational products. Marijuana and cannabis-based products are not an exception to these moderation laws and regulations that govern them, where the checks and balances are very similar to foods and pharmaceuticals consumer products. These are the existing regulatory Allowable Standard of Tolerance Level of cannabis products for Arsenic (0.2–1.5ppm), Cadmium (0.2-0.5ppm), Mercury (0.1–3ppm) and Lead (0.5-10ppm) metals.

The testing and analysis of heavy metals in cannabis products have become very crucial for moderation as some maybe toxic if ingested, inhaled or in dermal contact and its environment, and these can lead to adverse effect. With more heavy metal studies on cannabis-based oil products more awareness will be created.

The objective of this study is to identify the presence of Arsenic (As), Cadmium (Cd), Lead (Pb) and Mercury (Hg) metals in Cannabis oil, determine their concentrations, and how it compares to the set standards of different regulatory agencies. Amongst the varieties of sample matrices, an existing sample preparation procedure, analytical methods and applications, tested, proven and developed for inductively coupled plasma-based techniques, have been adopted and applied to 14 sourced Cannabis oil sample products.

The acid digested cannabis samples were analyzed using an Inductively Coupled Plasma-Mass Spectrometry instrument. This includes lower detection limits to nanogram-per-liter and / part-per trillion levels. The limits vary among states, and the results for the fourteen (14) cannabis samples showed that the concentration and standard deviation of the researched selected heavy metals are As75 (0.007786 ppm ± 0.013705) and Cd111 (0.007423 ppm ± 0.012793) relatively highest in cannabis samples 1 and 2, respectively. The Hg201 (0.000024 ppm ± 0.000053) and Pb208 0.000842 ppm ± 0.000995) are highest in samples 13 and 8, respectively.