Project on Weed

1. i
COVER PAGE
DETERMINE THE TRACE METAL IN URINE OF WEED SMOKERS AND NON
WEED SMOKERS
BY
FAVOUR NADERE
CST20NDEV2350
AND
ALASI FEMI RAYMOND
CSTND20EV3060
DEPARTMENT OF APPLIED CHEMISTRY
COLLEGE OF SCIENCE AND TECHNOLOGY,
SCHOOL OF APPLIED SCIENCE,
KADUNA POLYTECHNIC,
KADUNA.
NOVEMBER, 2023.

2. ii
TITLE PAGE
DETERMINE THE TRACE METAL IN URINE OF WEED SMOKERS AND NON
WEED SMOKERS
BY:
FAVOUR NADERE
CST20NDEV2350
AND
ALASI FEMI RAYMOND
CSTND20EV3060
THIS PROJECT IS SUBMITTED TO,
THE DEPARTMENT OF APPLIED CHEMISTRY,
COLLEGE OF SCIENCE AND TECHNOLOGY,
KADUNA POLYTECHNIC, KADUNA.
IN PARTIAL FULFILLMENT OF THE REQUIREMENT
FOR THE AWARD OF NATIONAL DIPLOMA (ND)
IN SCIENCE LABORATORY TECHNOLOGY
KADUNA POLYTECHNIC,
KADUNA
DEPARTMENT OF APPLIED CHEMISTRY
COLLEGE OF SCIENCE AND TECHNOLOGY,
SCHOOL OF APPLIED SCIENCE,
KADUNA POLYTECHNIC,
KADUNA.
NOVEMBER, 2023.

3. iii
DECLARATION
We hereby declared that this project work has been carried out solely by us under the guidance
and supervision of MRS. HAUWA UMAR of Applied Chemistry Department, Kaduna
Polytechnic, Kaduna. All literature cited are acknowledged by way of reference.
___________________________
FAVOUR NADERE DATE
CST20NDEV2350
___________________________
ALASI FEMI RAYMOND DATE
CSTND20EV3060

4. iv
DEDICATION
This project work is dedicated to God the creator of the universe, the owner and giver of
knowledge.

5. v
APPROVAL PAGE
This is to certify that this project is an original work undertaken by FAVOUR NADERE
CST20NDEV2350 and ALASI FEMI RAYMOND CSTND20EV3060, has been prepared
in accordance with regulation governing the preparation and presentation of project in Kaduna
Polytechnic, Kaduna.
______________________________ __________________________
Mrs. Hauwa Umar DATE
Project Supervisor
______________________________ ___________________________
Mrs. Hauwa Umar DATE
Chairman Committee
_________________________________ ___________________________
Dr. Idris Muhammad Kangiwa DATE
Head of Department
____________________________ ____________________________
External Examiner DATE

6. vi
ACKNOWLEDGEMENT
First of all, our appreciation goes to Almighty God who has given us the privilege to complete this
course successfully irrespective of the challenges.
Secondly, we acknowledge the contribution of our amiable supervisor (MRS. HAUWA UMAR)
who always created time to read through this work, made necessary corrections and helpful
suggestions. May God reward him abundantly (Amen). We equally appreciate the Head of
Department of Applied Chemistry (Dr. Idris Muhammad Kangiwa) and the entire SLT (Chemistry)
Lecturers.
We also want to thank our parent for their support in all ramifications towards the success of
our program. May God bless you all.
Concisely, we wish to extend our gratitude to our friends and our fellow colleagues. Thank you
all.

7. vii
TABLE OF CONTENTS
COVER PAGE.......................................................................................................................................i
TITLE PAGE ........................................................................................................................................ ii
DECLARATION.................................................................................................................................. iii
DEDICATION...................................................................................................................................... iv
APPROVAL PAGE .............................................................................................................................. v
ACKNOWLEDGEMENT................................................................................................................... vi
ABSTRACT.......................................................................................................................................... ix
CHAPTER ONE ...................................................................................................................................1
1.0 Introduction...............................................................................................................................1
1.1 Statement of Problem ...............................................................................................................2
1.2 Aims............................................................................................................................................2
1.3 Objective of study .....................................................................................................................2
1.5 Justification of study.................................................................................................................2
CHAPTER TWO ..................................................................................................................................3
2.0 Literature Review .....................................................................................................................3
2.1 Effects of Cannabis on Human Health....................................................................................6
2.2 Trace Metals and their Health Effects ..........................................................................................8
2.3 Empirical Review......................................................................................................................9
2.4 Analytical Techniques for Trace Metal Analysis.................................................................10
CHAPTER THREE............................................................................................................................12
METHODOLOGY .............................................................................................................................12
3.1 Reagent.....................................................................................................................................12
3.2 Procedure.................................................................................... Error! Bookmark not defined.
3.3 Sample Collection....................................................................... Error! Bookmark not defined.
3.2 Sample Analysis ......................................................................... Error! Bookmark not defined.

8. viii
CHAPTER FOUR...............................................................................................................................13
4.0 RESULTS ................................................................................................................................13
CHAPTER FIVE ................................................................................................................................15
DISCUSSION, RECOMMENDATION AND CONCLUSION......................................................15
5.1 DISCUSSION..........................................................................................................................15
5.2 RECOMMENDATION..........................................................................................................15
5.3 CONCLUSION .......................................................................................................................15
REFERENCE......................................................................................................................................16
APPENDIX............................................................................................. Error! Bookmark not defined.

9. ix
ABSTRACT
The proximate composition and analysis of cucumber and spinach leaves was to assess the
nutritional value of cucumber and spinach leaves by analysis the amino acid profile and
mineral constituents. The results showed that cucumber have the moisture content of 3.2% and
spinach 2.7%, fat content 13% on cucumber while spinach leaves 22.6%, crude fiber content
on cucumber 12% and spinach 1.15%, Ash content of cucumber 9.9% and spinach leaves 19%
respectively. Base on these finding, cucumbers and spinach are good source of vitamins and
minerals needed for building of the body.

10. 1
CHAPTER ONE
1.0 Introduction
Cannabis Sativa commonly known as weed, is one of the most widely used
psychoactive substances worldwide. The increasing legalization and decriminalization
of cannabis sativa in many regions have led to a rise in its consumption. While the
immediate effects of cannabis use are well-documented, there is growing concern about
the potential long-term health effects associated with its consumption. One area of
interest is the accumulation of trace metals in the body as a result of weed smoking
(Clarke R, et al, 2013).
Trace metals are elements present in the environment and can enter the body through
various sources, including air pollution, diet, and smoking. Weed smokers may be
exposed to trace metals through multiple routes, including the combustion of plant
material and the use of metal-based smoking paraphernalia. These metals can
potentially accumulate in the body and pose health risks over time (Johnson K. R. D et
al, 2020).
The determination of trace metal concentration in urine typically involves analytical
techniques such as atomic absorption spectrometry (AAS), inductively coupled plasma-
mass spectrometry (ICP-MS), or inductively coupled plasma optical emission
spectrometry (ICP-OES). These techniques offer high sensitivity and accuracy,
allowing for the detection and quantification of trace metals at low concentrations
(Jensen B & Chen J. et al, 2015).
Several trace metals are of particular interest in the context of weed smoking, including
lead (Pb), cadmium (Cd), Zinc (Zn), and Copper (Cu). These metals have been

11. 2
associated with various adverse health effects, such as neurotoxicity, cardiovascular
disease, and cancer. Evaluating their concentration in the urine of weed smokers can
provide insight into the potential risks associated with long-term cannabis use (J. Moore.
C & Weiss SR et al, 2009).
1.1 Statement of Problem
The determination of trace metal concentration in the urine of weed smokers faces
several challenges, which contribute to the overall problem of understanding the extent
of metal accumulation and potential health risks associated with cannabis consumption.
1.2 Aims
 This aim of this study is to determine the trace metal in urine of weed smokers and
non-weed smokers.
1.3 Objective of study
i. To determine trace metal concentrations in the urine of weed smokers.
ii. To compare between the levels of these metals in the urine of weed smokers
and non-weed smokers.
1.5 Justification of study
The determination of trace metal concentration in the urine of weed smokers is justified
due to the need to assess the potential health risks associated with metal exposure from
cannabis smoking. The study provides valuable insights into the specific risks, exposure
sources, and comparative analysis with non-smokers. The findings can inform public
health interventions, guidelines, and personal decision-making regarding weed
smoking, ultimately promoting safer practices and minimizing potential health
consequences.

12. 3
CHAPTER TWO
2.0 Literature Review
Cannabis Sativa also known as weed among other names, is a psychoactive drug from
the cannabis plant. Native to Central or South Asia, the cannabis plant has been used as
a drug for both recreational and entheogenic purposes and in various traditional
medicines for centuries. Tetrahydrocannabinol (THC) is the main psychoactive
component of cannabis, which is one of the 483 known compounds in the plant,
including at least 65 other cannabinoids, such as cannabidiol (CBD). Cannabis can be
used by smoking, vaporizing, within food, or as an extract (Schulz Chris et al, 2022).
Fig 1: Cannabis Sativa (Weed)
Cannabis sativa (weed) has a long history of human use. Cannabis Sativa (weed) has
been cultivated for its fibers and medicinal properties since ancient times. The earliest
evidence of cannabis use dates back to around 4000 BCE in Central Asia, where it was
likely used for its fibrous material in the production of textiles and ropes. Cannabis
played a significant role in ancient Chinese civilization (Ren, M., & Tang, Z. et al,
2005). The Chinese used hemp fibers to make clothing, paper, and fishing nets. The

13. 4
medicinal properties of cannabis were also recognized, and it was used in traditional
Chinese medicine for various ailments.
Cannabis sativa (weed) has various mental and physical effects, which
include euphoria, altered states of mind and sense of time, difficulty
concentrating, impaired short-term memory, impaired body movement (balance and
fine psychomotor control), relaxation, and an increase in appetite. Onset of effects is
felt within minutes when smoked, but may take up to 90 minutes when eaten (Curran,
H & Celia J.A et al, 2014). The effects last for two to six hours, depending on the
amount used. At high doses, mental effects can include anxiety, delusions
(including ideas of reference), hallucinations, panic, paranoia, and psychosis. There is
a strong relation between cannabis use and the risk of psychosis, though the direction
of causality is debated. Physical effects include increased heart rate, difficulty
breathing, nausea, and behavioral problems in children whose mothers used cannabis
during pregnancy; short-term side effects may also include dry mouth and red
eyes. Long-term adverse effects may include addiction, decreased mental ability in
those who started regular use as adolescents, chronic coughing, susceptibility
to respiratory infections, and cannabinoid hyperemesis syndrome (Ashton C. Heather
et al, 2012).
Cannabis sativa (weed) is mostly used recreationally or as a medicinal drug, although
it may also be used for spiritual purposes. In 2013, between 128 and 232 million people
used cannabis (2.7% to 4.9% of the global population between the ages of 15 and 65).
It is the most commonly used largely-illegal drug in the world, with the highest use
among adults in Zambia, the United States, Canada, and Nigeria. Since the 1970s, the

14. 5
potency of illicit cannabis has increased, with THC levels rising and CBD levels
dropping.
While cannabis plants have been grown since at least the 3rd millennium BCE,
evidence suggests that it was being smoked for psychoactive effects at least 2,500 years
ago in the Pamir Mountains, Asia. Since the 14th century, cannabis has been subject to
legal restrictions (Mathre ML, ed. Et al, 2010).
In the Middle East, Cannabis Sativa (weed) was cultivated for its fibers and seeds,
which were used for food and oil. Cannabis Sativa (weed) arrived in the Americas
during the colonial era. European settlers brought hemp seeds to the New World for
fiber production. Hemp was widely grown in North America, and it played a vital role
in early American colonies for producing ropes, textiles, and paper (Booth, M. et at,
2003).
In the 19th century, Cannabis Sativa (weed) was widely used in Western medicine.
Doctors prescribed cannabis extracts and tinctures to treat various conditions, including
pain, muscle spasms, epilepsy, and insomnia. Cannabis-based medicines were available
in pharmacies, and its therapeutic potential was widely recognized. The early 20th
century saw a shift in attitudes towards cannabis. Concerns about its psychoactive
effects, moral implications, and racial prejudices led to the criminalization of cannabis
in many countries. The United States enacted the Marihuana Tax Act in 1937,
effectively criminalizing cannabis at the federal level (Lee, M. A. et al, 2013).
In the 1960s and 1970s, Cannabis Sativa (weed) became associated with the
counterculture movement and was used recreationally by many. The social and political
movements of the time, including opposition to the Vietnam War and calls for civil

15. 6
rights, further propelled the popularity of cannabis use. Since the late 20th century,
there has been a growing recognition of the medicinal potential of cannabis. Many
countries and states have legalized medical cannabis to treat a range of conditions,
including chronic pain, multiple sclerosis, epilepsy, and nausea associated with
chemotherapy (Campbell, E. et al, 2012).
In recent years, there has been a significant shift in attitudes towards Cannabis Sativa
(weed). Several countries and states have legalized or decriminalized recreational
cannabis use. The cannabis sativa (weed) industry has also seen tremendous growth,
with increased research, product development, and regulation.
2.1 Effects of Cannabis on Human Health
The effects of Cannabis Sativa (weed) on human health can vary depending on various
factors, including the dosage, frequency and duration of use, individual susceptibility,
and the specific compounds present in cannabis.
i. Psychoactive Effects: Cannabis Sativa (weed) contains compounds called
cannabinoids, with delta-9-tetrahydrocannabinol (THC) being the primary
psychoactive component. When consumed, THC binds to cannabinoid receptors in the
brain, leading to various psychoactive effects. These can include euphoria, relaxation,
altered perception of time, and heightened sensory experiences (Shufman E & Witztum
E et al, 2005).
ii. Short-Term Cognitive Effects: Acute Cannabis Sativa (weed) use can affect cognitive
function. Short-term effects may include impaired memory, attention, and
concentration, making tasks requiring cognitive skills more challenging. These effects
are generally temporary and may subside as the acute effects of cannabis wear off.

16. 7
iii. Respiratory System: Smoking Cannabis Sativa (weed), like smoking tobacco, can
have adverse effects on the respiratory system. Regular cannabis smoking can lead to
respiratory symptoms such as chronic cough, phlegm production, and bronchitis.
Additionally, cannabis smoke contains harmful compounds and carcinogens, which
may increase the risk of respiratory problems and lung cancer (Johnson BA et al, 2014).
iv. Mental Health: Cannabis Sativa (weed) use has been associated with various mental
health effects, although the causal relationship is complex and not fully understood.
Some individuals may experience heightened anxiety, paranoia, or panic attacks after
using cannabis. For those predisposed to mental health conditions, cannabis use,
particularly in high doses or during adolescence, may increase the risk of developing or
exacerbating psychiatric disorders such as schizophrenia.
v. Addiction and Dependence: Cannabis Sativa (weed) use can lead to the development
of dependence and addiction, particularly in individuals who use it regularly and
heavily. Cannabis Sativa (weed) use disorder, characterized by impaired control over
cannabis use, withdrawal symptoms upon cessation, and negative impacts on various
areas of life, can occur in susceptible individuals.
vi. Cardiovascular Effects: Acute Cannabis Sativa (weed) use can cause an increase in
heart rate and temporary blood pressure elevation. For individuals with pre-existing
cardiovascular conditions, cannabis use may pose a higher risk, potentially leading to
adverse cardiovascular events such as heart palpitations, heart attack, or stroke.
vii. Therapeutic Potential: Despite potential risks, cannabis and its derivatives have
shown promise in medical settings. Cannabidiol (CBD), another compound found in
cannabis, has been studied for its potential therapeutic effects in conditions such as

17. 8
epilepsy, chronic pain, multiple sclerosis, and nausea associated with chemotherapy.
However, further research is needed to establish the efficacy, safety, and optimal dosing
of cannabis-based medicines (Baler, R. D, 2014)
2.2 Trace Metals and their Health Effects
Trace metals are elements present in very small amounts in the environment, food, and
human body. While these metals are essential for various biological processes at low
concentrations, excessive exposure or accumulation can lead to adverse health effects. Here
are some common trace metals and their potential health effects:
i. Lead (Pb): Health Effects: Lead exposure can cause neurological, cognitive, and
developmental impairments, particularly in children. It can lead to learning disabilities,
reduced IQ, behavioral problems, and delayed growth. Lead exposure in adults can
result in high blood pressure, kidney damage, and reproductive issues.
ii. Cadmium (Cd): Health Effects: Cadmium exposure primarily affects the kidneys and
can lead to kidney dysfunction and damage. Prolonged exposure may also cause lung
damage, bone mineral density loss, and increase the risk of certain cancers, such as lung
and prostate cancer.
iii. Copper (Cu): Health Effects: Copper is an essential trace element required for various
enzymatic processes in the body. However, excessive copper levels can lead to copper
toxicity, causing gastrointestinal symptoms, liver damage, and neurological disorders.
iv. Zinc (Zn): Health Effects: Zinc is also an essential trace element involved in numerous
physiological processes. While excessive zinc intake from supplements or certain
sources can lead to gastrointestinal disturbances and copper deficiency, zinc toxicity is
relatively rare.

18. 9
It's important to note that the health effects of trace metals depend on the dose, duration
of exposure, individual susceptibility, and the specific form of the metal. Environmental
regulations, occupational safety measures, and dietary guidelines aim to minimize
exposure to harmful levels of trace metals and ensure human health and safety (Morton,
J., Mason, L.Lee, M. R., 2020).
2.3 Empirical Review
While there is limited research specifically focused on trace metals in cannabis users,
studies have explored the presence of heavy metals, including trace metals, in cannabis
and its related products. Here are a few previous studies that have investigated trace
metal content in cannabis:
"Heavy metal and cannabinoid content of medicinal cannabis products" (2018) this
study analyzed the heavy metal content, including trace metals, in various medicinal
Cannabis Sativa (weed) products available in Canada. The researchers found detectable
levels of several heavy metals, including lead, cadmium, although the concentrations
were generally below regulatory limits.
"Analysis of metals in cannabis and cannabis smoke" (2013) this study examined the
presence of heavy metals, including trace metals, in Cannabis Sativa (weed) plant
material and the smoke generated from burning cannabis. The researchers found
measurable levels of several metals, such as lead, cadmium, arsenic, and nickel, in both
the plant material and the smoke.
"Evaluation of metals in cannabis pipes and smoke" (2018) this study investigated the
presence of metals, including trace metals, in Cannabis Sativa (weed) pipes and the
smoke generated from smoking cannabis. The researchers found that cannabis pipes

19. 10
made from certain materials, such as brass or copper, released measurable amounts of
metals, including lead, into the smoke.
"Heavy metals exposure and marijuana" (2011) This study examined the levels of heavy
metals, including trace metals, in marijuana samples obtained from illicit markets in the
United States. The researchers found varying levels of several metals, such as lead,
cadmium, arsenic, and nickel, in the tested samples.
2.4 Analytical Techniques for Trace Metal Analysis
The choice of technique depends on factors such as the nature of the sample, the
required sensitivity, the target elements, and the desired analytical parameters. Here are
some commonly employed techniques for trace metal analysis:
i. Atomic Absorption Spectroscopy (AAS): AAS is a widely used technique for
determining the concentration of specific metals in a sample. It operates based on the
absorption of light by the analytic atoms in the ground state. AAS can be used for both
flame and graphite furnace atomization, offering good sensitivity and selectivity for a
range of metals.
ii. Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES): ICP-OES
utilizes an inductively coupled plasma to atomize and excite the sample. The resulting
emission spectra are then analyzed to determine the elemental composition. It offers
excellent sensitivity, multi-element capability, and a wide dynamic range for metal
analysis.
iii. Inductively Coupled Plasma-Mass Spectrometry (ICP-MS): ICP-MS combines an
inductively coupled plasma with a mass spectrometer to provide simultaneous multi-
element analysis. It offers exceptional sensitivity and low detection limits, making it

20. 11
suitable for trace metal analysis. ICP-MS can quantify a wide range of elements and
isotopes.
iv. Atomic Emission Spectroscopy (AES): AES measures the emission of light from
excited atoms to identify and quantify the elemental composition of a sample. It is
commonly used for qualitative and quantitative analysis of metals. Flame or plasma
sources can be employed depending on the sample and analytical requirements.
v. X-ray Fluorescence Spectroscopy (XRF): XRF measures the characteristic X-ray
fluorescence emitted by a sample when it is irradiated with X-rays. It can provide semi-
quantitative to quantitative analysis of major and trace elements. XRF is non-
destructive and suitable for solid, liquid, and powdered samples.
vi. Voltammetry: Voltammetry involves measuring the current flowing in an
electrochemical cell as a function of the applied voltage. Techniques like differential
pulse voltammetry (DPV) and anodic stripping voltammetry (ASV) are employed for
trace metal analysis. They offer good sensitivity and can be used for both qualitative
and quantitative analysis.
These techniques represent a selection of commonly used methods for trace metal analysis.
Each method has its strengths and limitations, and the choice of technique depends on the
specific requirements of the analysis (Lin, L., & Zheng, Y. 2019).

21. 12
CHAPTER THREE
METHODOLOGY
3.1 Sample Collection
The sample in this research are the urine of weed smokers and non-weed smokers. 5
weed smokers and 5 non-weed smokers’ samples were collected at different location in
Kaduna, and stored in the refrigerator ready for digestion.
3.2 Sample Digestion
20ml of the sample was measured into 250ml of breaker. They were digested with 3ml
of nitric acid and 10ml of hydrochloric acid. The samples were heated on the hot plate
and were allowed to evaporate until 6ml was left. Then the sample were allowed to cool
and 10ml of distilled water was added to the solution and stirred. This was then filtered
with wanton 0.45NM pure size cellulose nitrate membrane filter paper and the volume
was increase to 30ml with distilled water. It was then stored in the sample bottle for the
analysis using atomic absorption spectrophometry. This was repeated for all other
sample.
3.3 Sample Analysis
Reagent blanks used to zeroing while taking the reading of sample containing
respective metals.
The sample solution was then aspirated into the flame and on absorbance reading was
recorded. Calibrated curve of the absorbance reading of standard solution for each metal
was plotted. The reading of each sample was calculated by taking the average reading
of the triplicate sets.

22. 13
CHAPTER FOUR
4.0 RESULTS
Table 4.1: Concentration of Heavy metals in Weed Smokers.
SAMPLE Zn (Mg/1) Cd(Mg/1) Pb(Mg/1) Cu(Mg/1)
1 ±0.5381 ±0.007 ±0.1228 ±0.2935
2 ±0.9831 ±0.0175 ±0.0687 ±0.2688
3 ±0.6504 ±0.0179 ±0.3576 ±0.292
4 ±0.9727 ±0.0196 ±0.0464 ±0.2984
5 ±1.5639 ±0.0446 ±0.0388 ±0.3524

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Table 4.2: Concentration of Heavy metals in Non-Weed Smokers.
SAMPLE Zn (Mg/1) Cd(Mg/1) Pb(Mg/1) Cu(Mg/1)
1 ±0.9807 ±0.0256 ±0.0162 ±0.156
2 ±1.4257 ±0.0361 ±0.0379 ±0.1807
3 ±1.093 ±0.0365 ±0.3268 ±0.2039
4 ±1.4153 ±0.0382 ±0.0156 ±0.2103
5 ±2.0065 ±0.0632 ±0.008 ±0.2643

24. 15
CHAPTER FIVE
DISCUSSION, RECOMMENDATION AND CONCLUSION
5.1 DISCUSSION
The result shows the concentration of heavy metals on weed smokers and non-weed
smokers. The level of Zinc (Zn) found in the urine samples of weed smokers ranged
from 0.5381 to 1.5639, while non-weed smokers ranged from 0.9807 to 2.0065,
Cadmium (Cd) concentration level of heavy metals in weed smokers ranged from 0.007
to 0.0446, non-weed smokers ranged from 0.0256 to 0.0632. Weed smokers have the
highest level of heavy metals on Lead (Pb) which ranged from 0.1228 to 0.0388, while
non-weed smokers ranged from 0.0162 to 0.008. The Copper (Cu) concentration of
heavy metals on weed smokers ranged from 0.2935 to 0.3524, non-weed smokers
concentration of heavy metals ranged from 0.156 to 0.2643.
5.2 RECOMMENDATION
This work is recommended for all those who want to carry out further research in this
field. It is also recommended that weed smokers should adhere strictly to the warning
of World Health Organization against smoking.
5.3 CONCLUSION
Based on the analysis carried out on the determination of the level of trace metals
concentrations in the urine of cigarette weed smokers, it can be concluded that the
concentration level of lead, copper and lead were relatively higher than those values of
the control (non-weed smokers) while the concentration of zinc in the urine of weed
smokers were lower than the average urinary concentration. This report show that weed
smokers are more exposed to trace metals than the non-weed smokers.

25. 16
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