ABSTRACT
In this research work, Quality assessment of varieties of toothpastes used in Nigeria was investigated in this study. Ten different brands of toothpastes were purchased from the open market in Kaduna, Nigeria and their physicochemical properties, bacterial load, fluoride, heavy metal levels, titanium, saccharin and sodium lauryl sulphate (SLS) concentrations were determined using Standard methods. The pH of these toothpastes was found to range from between 5.20 to 8.42. 60% of the sampled toothpastes fell within the NAFDAC recommended pH range of 6.5 to 7.5. The moisture and volatile constituents of the toothpastes were between 28.03% and 46.19%, which is within the range set by NAFDAC. The fluoride concentration of the sampled toothpastes ranged from 770 ± 13.46 ppm to 1220 ± 5.00 ppm. Although none of the toothpastes was above the maximum limit of 1500 ppm fluoride as set by NAFDAC, three were found to be below the minimum set value of 850 ppm as required by NAFDAC. The results from the microbial load of the toothpastes showed that they were all sterile as no bacterial or fungal isolates were identified in any of the sampled toothpastes. Traces of titanium metals were found in all the sampled toothpastes ranging from 1.44 to 6.25 mg/g. While traces of heavy metals like Cd, Mn, Ni, Co and Zn were detected in the toothpaste samples. Lead was absent in all the sampled toothpastes. The concentration of saccharin in the analyzed toothpastes ranged between 83.3 ± 17.29 to 232.86 ± 11.47 mg/g while SLS ranged between 15.64 ± 10.11 to 21.30 ± 10.22 mg/g. The concentrations of the heavy metals and saccharin in the sampled toothpastes where compared with the level for their acceptable daily intake. It was deduced that users of this products were likely to be exposed to high risk of health issues if toothpaste which was meant for brushing the tooth is swallowed mistakenly.
vii
A comparative study of the concentration of heavy metals in local toothpastes with the foreign toothpastes showed that foreign toothpastes contained higher concentration of these heavy metals and may pose greater health problem to consumers. Therefore there is the need to sensitize consumers on the dangers involved in swallowing toothpastes and based on the results obtained from this research work, it is recommended that the importation of foreign toothpastes should not be encouraged.
TABLE OF CONTENTS
Title Page………………………………………………………………………………i
Declaration…….………………………………………………………………………ii
Certification………..……………………………………………………..…………….iii
Acknowledgement…………………….……..……………………………..………….iv
Abstract……………………..………..…..……………………………………….……v
Table of Content………………………………………………………………………………………….…..vii
List of Figures…………………….……………………………………………..….…xii
List of Tables……………………………………………………………………………….xiii
List of Appendices……………………………………………………………………..xiv
Abbreviations ……………………………………………………………………..……xv
1.0 INTRODUCTION………………………………………………………..……1
1.1 Preamble….……………………………………………………………….……..1
1.2 Research Problem……………………..……………………………………….5
1.3 Aim……………………………………………..………………………….……6
1.4 Objectives…………………………………………………………….………….6
1.5 Justification of Research…………………………………………….…………7
2.0 LITERETAURE REVIEW……………………………….….……..….……..8
ix
2.1 Saccharin……………………………………………………………………………………….……8
2.1.1 History…………………………………………………………………………………………………8
2.1.2 Chemistry…………………………….…………….……………………………….9
2.1.3 Biochemical data…………………………….…………….………..….……..10
2.1.4 Research works on saccharin……………..………………….…..………….….12
2.2 Sodium Lauryl Sulphate (SLS)………………………………….…………..16
2.2.1 Side effect of SLS…………………………………………………..…….……17
2.2.2 Analysis of SLS…………………………………………………………….….20
2.3 Fluoride…………………………………………………………………………21
2.3.1 Cavity prevention………………………………………………………..……..21
2.3.2 Toxicology………………………………………………………………..…….22
2.3.3 Fluoridated toothpaste……………………………………………………..…..23
2.3.4 Analysis of fluorides in toothpastes……………………………………………24
2.4 Heavy Metals…………………………..………………………………….…..25
2.4.1 Sources and toxicology of selected heavy metals………………………………………27
2.5 Other Research Works on Toothpastes…..…………..………..…………….36
2.6 Analytical Techniques…………………..…………………………….……….37
x
2.6.1 Theory of X-Ray spectrophotometer……………………..………….………..37
2.6.2 Theory of uv -spectrophotometer…………………………………….…… ..38
2.6.3 Theory of AAS……………………………………………………….………40
2.6.4 Principle of operation of HI 83200 photometer………………………..….…40
3.0 MATERIALS AND METHODS……..…………….…..…………….……42
3.1 Materials / equipment………..…………………..………….……….…..…42
3.1.1 List of apparatus and equipment…………………………………………….42
3.1.2 List of reagents and chemicals (Analar grade)…………….………………….43
3.2 Reagent and Preparation of Solution………………….……..…..………..44
3.2.1 Sodium nitrite solution ………………………………………………………..44
3.2.2 Diazotization of 4-nitroaniline ………………………………………………..44
3.2.3 Alizarin solution ……………….…………………………………………….45
3.2.4 Zirconyl acid …………………………………………………………..…….45
3.2 Sampling………………………………………………………………..……45
3.3 Analysis of Physical Parameters……………………………………….……45
3.3.1 Colour…………………………………………………………………………45
3.3.2 Moiture and Volatile Content…………………………………………..…….45
xi
3.3.3 pH Value……………………………………………………………..………46
3.4 Microbial Purity Test……………………………………………………….46
3.5 Determination of Fluoride Content……………………………………….46
3.6 Determination of Titanium………………………………………………….47
3.7 Heavy Metal Analysis……………………………………………..…….…..47
3.8 Determination of SLS…………………………………………….….………48
3.9 Determination of Saccharin……………………………………….….……48
4.0 RESULTS AND ANALYSIS……………………….……………….…….49
4.1 General Characteristics of Samples………………………………………..49
4.2 Bacteriological Examination……………………………………….………49
4.3 Physicochemical Parameters of samples…………………….…………….49
4.4 Analysis of Fluoride Concentration in Toothpaste……………….………52
4.5 Analysis of Titanium and Other Heavy Metals in Toothpaste.……..……52
4.6 Analysis of Saccharin and SLS Concentration in Toothpaste…….……..62
4.7 Statistical Analysis of Data……………………….…………..……….……62
5.0 DISCUSSION…………………………………………………….…………71
6.0 CONCLUSION AND RECOMMENDATIONS…………………………81
xii
6.1 Conclusion…………………………………………………………………81
6.2 Recommendation………………………………………………………….84
REFERENCES…………………………………………………………….……..85
APPENDICES………………………………………………………………..…..99
CHAPTER ONE
INTRODUCTION
1.1 Preamble
Toothpaste is a substance in molten form used with a toothbrush as an accessory to clean and maintain the aesthetics and health of teeth. Toothpaste is a personal hygiene product used on daily basis by children and adults. The chemical composition of toothpaste varies from one brand to another and even among several presentation of the same brand. They are composed of substances which act as abrasive, pigment, foam inducer, humectants, thickener, stabilizer, solvent, sweetener, therapeutic agent and enamel hardener.
The primary purpose of brushing the teeth with a dentifrice (toothpaste) is to clean the accessible tooth surface of dental plaque, stains and food debris. Tooth cleaning with dentifrices dates back over 2000 years, while cleaning of teeth with toothpicks and brushes is an older practice. Abrasive dentifrice materials came to be used when it was found that brushes while facilating the cleaning of soft deposit from teeth, were inadequate for the removal of harder deposits and stains. Dentifrices have been prepared in several forms such as powder, paste and gels. The most popular forms are the pastes and gels with over 5 billion tubes used worldwide each year (Eric, 1994).
Several studies have shown that toothpaste has a key role in helping to remove dental plaque, the major cause of dental caries and periodontal diseases (Forward, 1991). Apart from aiding cleaning of teeth directly, tooth paste has a role in encouraging people to clean their teeth. Modern developments in toothpaste formulation have led to the addition
2
of agents to provide therapeutic, as well as cosmetic benefits. Frequently used modern toothpaste can help prevent dental caries and limit the re growth of dental plaque.
A typical chemical composition of toothpaste includes: abrasives (20% – 50%), flavor (20%) which is pleasant and must be associated with a clean feeling e.g. mint flavor, colouring (<1%), sweetening agents (2%) and water (20% – 40%).
Modern toothpaste is a heavy mix of chemical and other synthetic materials to clean, polish and maintain healthy teeth and gums. Most commercial toothpaste has ingredients such as sodium lauryl sulphate, sodium saccharin, titanium oxide, and fluoride and in some cases, heavy metals and microbial contamination, which may cause health challenges with time.
Saccharin (1,2-benzisothiazolin-3-one-1,1-dioxide) is an artificial sweetener. It is believed to be an important discovery, especially for diabetics, as it goes directly through the human digestive system without being digested. Although saccharin has no food energy, it can trigger the release of insulin in human and rats, presumably as a result of its taste (Just et al., 2008; Lonescu et al, 1988; Berthoud et al, 1980), as can other sweeteners like aspartame. Consumption of saccharin and other artificial sweeteners have been shown to increase the risk of bladder cancer in humans (Howe et al, 1977; 1980; Hoover and Hartge, 1982). It has also been tied to a variety of allergic reactions including headaches, breathing issues, skin rashes and diarrhea (Stewart, 2011). Recent studies show that saccharin can actually increase body weight (Polyak et al., 2010). In infants, it can cause irritability and muscle dysfunction (Tulika, 2011). Pregnant women have also been advised to avoid the use of saccharin in pregnancy, as saccharin has the ability to pass through the
3
placenta and it may remain in the fatal tissue, which is harmful for the unborn child (Janet, 2002).
Sodium lauryl sulphate (SLS) is a surfactant, detergent and emulsifier, used in thousands of cosmetic products, as well as in industrial cleaner. It is present in nearly all shampoos, scalp treatments, hair color and bleaching agents, toothpaste and body washes.
Studies on SLS shows that it can cause irritation of the skin, eyes, respiratory system if inhaled (Lee et al., 2004). SLS in mouth rinses can cause desquamation of oral pithelium and a burning sensation in humans (Babich and Babich, 1997). SLS is associated with increased aphthous ulcers (cancer sores) due to the denaturing effect and irritation of the oral mucosa (Herlofson and Barkvoll, 1994).
Fluoride, a key ingredient in toothpaste has broad benefits for people, both young and old. The fluoride in toothpaste heals and remineralizes microscopic cavities as they form, it hardens the tooth surface, making it more resistant to the acid attack of bacteria and slows down the action of these acid producing bacteria. Though a small amount of fluoride is beneficial, it has been shown to cause mottled teeth and bone damage at about 5mg/L in water (Tokalioglu et al., 2004). Studies have shown that bone cancer in male children and uterine cancer deaths are linked to water fluoridation due to fluorides gradual build up in the bones, thereby causing adverse changes to the bone structure (Varner et al., 1998). Fluoride has also been reported to cause birth defects and perinatal deaths, impaired immune system, acute adverse reaction, severe skeletal fluorosis at high levels, osteo- arthritis, acute poisoning and contributes to the development of repetitive stress injury (Holistic, 2009).
4
Titanium dioxide is widely used to provide whiteness and opacity to products such as paints, plastics, papers, ink, food and toothpaste. It is also used in cosmetic and skin care products. It has been reported that high concentration of titanium dioxide dust may cause coughing and mild, temporary irritation, long-term inhalation of high concentration of pigmentary (powdered) or ultrafine titanium dioxide may cause lung cancer based on animal evidence (Han et al., 2012).
Titanium dust, has been classified by the international Agency for Research on Cancer (IARC) as an IARC group 2B carcinogen, meaning it is possibly carcinogenic to human (IARC, 2006). It has also been shown to cause respiratory track cancer in rats exposed by inhalation and intra tracheal instillation (Kutal and Serpone, 1993). Recent data indicated that TiO2-nanoparticles are cyto- and genetoxic against several lineages of cell cultures. They also present high carcinogenic potential in animal models (Huang et al., 2009; Trouiller et al., 2009). Wide spread use and its potential entry through dermal, ingestion and inhalation routes suggest that nano sized TiO2 poses considerable exposure risks to humans, livestock and eco-relevant species (Long et al., 2006).
Many heavy metals are not acceptable as ingredient in oral products, as they may pose health challenges to users. Yet, they may still be found in oral products as impurities due to the persistent nature of these substances and the fact that they are found naturally in the environment. Heavy metals, being added deliberately as ingredient in toothpaste, has been curtailed, however, the presence of these substances as impurities in toothpaste calls for concern. Popova and Marinova, 2007, in a recent research, reported that metals used in dentistry are known to cause contact dermatitis in the mouth. The metals of primary toxicological concern are lead, cadmium, titanium, nickel, manganese, copper and zinc.
5
Bacterial contamination can pose a potential health risk for humans. The illness associated with bacterial contamination includes gastro-intestinal infections and other life threatening infections. Microbial contamination can be found in food, water, cosmetics and toothpastes (Jennifer and David, 2012). Although microbial contamination in toothpaste is not common, it has recently been reported in some counterfeit toothpaste sold in the US (Jennifer and David 2012). Hence, it is necessary to test these brands of toothpaste products against microbial contamination.
1.2 Research Problem
Various companies now manufacture toothpastes under different brand names without giving the percentage composition of the ingredient used. Some toothpaste sold in Nigeria today and some imported ones do not carry the registration numbers from regulatory bodies, meaning they have not been screened. Some of the constituent chemicals used include SLS, Sodium Saccharin, Fluoride, Titanium dioxide which have been proved to be hazardous to the human health, if above a certain limit.
Recently, most manufacturers make use of plant extracts to make herbal toothpaste. This can further lead to contamination of the toothpaste by microorganisms as well as heavy metals due to their persistent nature.
Despite the health implication of the presence of these substances in food, they are still used in food products in minimum amounts.
In Nigeria, toothpaste is used by both adults and children. Reports show that children and some adults ( pregnant women especially), swallow a substantial amount of
6
toothpaste in the process of brushing , which could lead to any of the effects associated to the ingestion of these substances. (Hernandez et al., 1985)
1.3 Aim
This work aimed at assessing the quality of some selected locally and foreign manufactured toothpastes, used in Nigeria Markets.
1.4 Objectives
The aim of this research will be achieved through the following objectives;
i. Evaluation of some physical parameters of toothpaste (colour, moisture and volatile content, pH) using recommended methods.
ii. Investigation of the bacteriological and microbial status of the toothpaste, using standard methods.
iii. Investigation of fluoride concentration in toothpaste samples.
iv. Determination of Heavy metals levels (Pb, Cd, Mn, Cu, Ni and Zn) and TiO2 contamination in toothpastes using AAS and x-ray Spectrometer respectively.
v. Investigation of sodium saccharin, sodium lauryl sulphate concentration in the selected toothpaste using UV-Spectrophotometer.
vi. Carry out correlation analysis to compare the levels of these substances in the foreign and local toothpastes.
vii. Comparing the obtained results with set standards by regulatory bodies.
7
1.5 Justification of Research
Toothpaste is used on daily basis by children and adults to promote oral hygiene. Available evidence shows that children and pregnant women are exposed to high risk of health problem if they continue to consume toothpaste. There is therefore need for continuous monitoring of levels of potentially hazardous substances in toothpaste and also to check the quality of this product available to consumers. Recommendation(s) can then be made to manufactures of toothpastes on how to adjust their formulations.
8
Do you need help? Talk to us right now: (+234) 08060082010, 08107932631 (Call/WhatsApp). Email: [email protected].
IF YOU CAN'T FIND YOUR TOPIC, CLICK HERE TO HIRE A WRITER»
