By Tan Luck Pheng & Eddie Lee Kong Soon

INTRODUCTION

In our daily use of cosmetics and toiletries, we discharge vast amounts of chemicals ingredients, antiseptics and preservatives into our environment. Although the more harmful chemicals such as phenols, parabens, formaldehyde, pyrithione, trichlocarban, triclosan and others are used in small amounts, normally below 0.3%, we worry about their possible cumulative effect on our ecological system and our health. In the search for a natural and safe replacement for antiseptic and preservative compounds, silver offers a suitable substitute. The urgency of making such substitution is even more compelling in view of the abuse on antibiotics due to:-
(1) Over prescription of antibiotics.
(2) Patient not completing full dosage
(3) Use of antibiotics in animals.
(4) Increase in cost of antibiotics.

We all know antibiotics never affect virus, yet 3 million pounds of antibiotics are given in USA to patients affected by viral infections. About 80% of antibiotics in US are used in animal feed. In fact, the whole world is pouring away antibiotics with no apparent purpose. This results in breeding more resistant bacteria such as killer E.Coli, “Flesh-eating” staphylococcus aures, multiple antibiotic resistant tuberculosis bacteria and chloroquine resistant malarial parasites.

THE USEFULNESS OF SILVER

Silver wares were used by ancient Greeks Romans to store perishable liquid and to prevent spoilage, while the ancient Chinese warriors used silver preparations to threat arrow wounds long before they knew the existence of infectious microorganisms. Early American settlers threw silver dollars into milk to delay spoilage during long distant delivery. During the outbreak of plaque in Europe, the royal and noble families used silver wares to handle foods and were saved from the deadly disease. Their children were given silver spoon to suck; hence the saying of “born with a silver spoon” is used today to refer to the rich and noble families. Some of them ingested so much silver that they even developed mild argyria characterized by bluish skin, hence the terms “blue blood” or “royal blue” were originated. In early days, silver sulphadiazine was used to cure syphilis and other infectious diseases.

THE CREATION OF SILVER BULLET

In 1923 Western Reserve University of Clevel and used silver nitrate to combat harmful microorganisms and in 1970 NASA found that silver ions could kill infectious agents over 2 hours at part per billion (ppb) concentration. More recent test at Brigham Young University, Utah demonstrated that below 5 ppm nanosilver solution could inhibit or kill bacteria, yeast and fungi. In our preparations, we confirm that at 10 ppm, they kill 99.5% of E. Coli and straphylococus aureus within 10 minutes of exposure. Nanosilver solution at such a low concentration as 10 ppm is considered as food or mineral water as certified by our Ministry of Health. Indeed, the accumulation of information on its antiseptic property and environmental safety, triggers us to the idea of developing a natural, safe and effective “silver bullet” against harmful microorganisms. Recent progress in nanotechnology enables us to examine the possibility of creating this silver bullet.

Pure silver bar (99.999%) is subjected to high voltage electrolysis to yield silver aggregates which are in turn repeatedly drawn apart into smaller aggregates and eventually into ultrafine aggregates of below 30 atoms of less than 10nm diameter. During this process, some of these atoms acquire positive charge due to the loss of as much as 3 electrons, from the outermost shelf. Charged and uncharged silver atoms and ions suspend in water known as silver colloid as they do not precipitate. We went on to standardise our preparations using electron-microscopy to monitor the size and used the Siemens micro-conductivity meter to monitor the charge.

Being ultrafine aggregates as shown under the electron-microscopy and positively charged, they are extremely active in attacking microorganisms like bacteria, yeast, fungi, mould and possibly virus whose cell walls are negatively charged. After standardizing the charge, size and concentration of nanosilver of our preparations, we investigated the effectiveness of our preparations on various health problems.

We have found that our nanosilver preparations are effective in the relieving and healing of wounds, insect bites, burns, bed sore, sore-throat, ENT infections, diarrhea and animal farm diseases caused by microorganisms in chicken, goat and pig.

THE ENVIRONMENTAL FRIENDLINESS OF SILVER

American EPA (Environment Protection Agency) rules that there is no risk at all for consuming 7x5ml (teaspoons) of 10 ppm nano-silver solution for 70 years. WHO estimates that most people consume between 20 to 50ug of silver per day. Even more remarkable is the reports that at such a low concentration nanosilver could destroy pathogenic organisms but give no harm to the non-pathogenic flora. In other words, it does not interfere with bifidobacteria.

Studies on animals like mice, rats, monkeys and dogs by oral, intravenous and intraperitoneal routes, show that 90% of the nanosilver animals has less that 1% of the initial dose after 1 week. In one study, Roger Altman reported that 75% of orally consumed silver was eliminated via urine in man on the same day. The discharged silver atoms replenish the natural cycle to form bigger silver aggregates which gradually increase in size and can be harvested by man. In larger sizes, they are inert and do not pose as a hazard or risk.

NANOSILVER PRODUCTS

After going through all the safety data, we are more confident with our products. Last year, 2007, we manufactured and marketed three products in three different brands:-
(1) Nanosilver transparent soap, 10 ppm
(2) Nanosilver normal and nasal spray, 10 ppm.
(3) Nanosilver gel, 25 ppm for skin care purpose.

This year, more brands and varieties of such products are going into the market. We have incorporated nanosilver as a natural ingredient in our cosmetic and toiletry products to:-
(1) Improve the product safety and performance particularly on its antiseptic effect.
(2) Improve the stability of product in place of chemical preservatives.
(3) Reduce skin allergy by avoiding chemical compounds.
(4) Reduce chemical pollution in our environment with this natural non-toxic and safe element.

The marketing of nanosilver preparations as medical products is more complicated as medical claims require clinical data to substantiate them. In Malaysia, it is extremely difficult to collaborate with clinical researches in hospitals or research institutes to carry out meaningful research programmes. The staff are overloaded with work while the establishments are either not interested or not equipped for such studies. It will be very sad indeed, if we are unable to benefit at first hand from the great potential of nanosilver in medicine.

THE USE OF OTHER NANO PARTICLES IN COSMETICS

It would be a disaster if we were to assume that the conversion of inert and safe big particles like silver into ultrafine particles like nanosilver will have the same safety profile without careful evaluation of its safety data. In cosmetics, nano particles such as silicone and titanium dioxide are used extensively. Nano particles of silicone are used as thickener or as sealing or coating agents. While nano particles of titanium oxide is used as whitener in toothpaste or as a UV protector in sunscreen cream. Recently, EPA in North Caroline reported that titania (nano particles of titanium dioxide) provokes the microglia in cultured mice cells, to produce reactive oxygen species (ROS) which normally are useful to oxidize the harmful foreign substances. Long term production of ROS will create oxidative stress to the cells and neighbouring cells like the nerve cells which are meant to be protected by these microglias. In the same system, they also reported that tinatia nano particles can trigger the death of nerve cells. If the nerve cells in the brain are placed under long term oxidative stress, it can cause neurodegenerative diseases such as Parkinson’s or Alzheimer’s disease.

This example warns us to be cautious in the application of nano particles of compounds which are safe to use at larger sizes. In the nano size, their reactivity, rate and extent of penetration into the body must be properly assessed. The blood-lymph and blood-brain barrier can no longer restrict the access of these nano sized chemicals. The hazard of less that 100nm ultrafine particles comes from inhalation, ingestion, transdermal absorption and these fine particles allow for uptake into the cells and by transcytosis across epithelial endothelial cells into the blood, lymph circulation to reach the potentially sensitive target sites like bone marrow and brain. They can be translocated along neuroaxons and dendrites to the neural cell bodies. The greater surface area per mass compared with large-sized particles of the same property, renders them more active biologically.

In our assessment on the margin of safety for a substance to be used in cosmetics, we only need to know the No Observable Adverse Effect Level (NOAEL) and the amount presence in the blood or Systemic Exposure Dose (SED). With the introduction of ultrafine particles, we need to know that level of these ultrafine particles at the subcellular level. The toxicological difference between the ultrafine particles and its big parent particles is not only its intrinsic chemical properties but to a large degree to its different kinetics in vivo.

Unlike its parent titanium oxide, titania can enter central nervous system and translocate to the nerve cell bodies in the brain or spinal cord via the axons. We, therefore, require toxicological data at sub-cellular level to work out a more meaningful margin of safety.

NANO PRODUCT IN ELECTRONIC INDUSTRY

We are more worried about the 10nm quantum dots consisting of cadmium and lead used in semi-conductor metal compounds. When these semi-conductors are used and discarded, these micro dots are released and they get into our water source which is consumed by all of us. Nothing is known about its effect on the sub-cellular structures, ecological system and our health. Will these ultrafine particles interfere with our genetic materials? Will they interfere with the development of our offsprings? Will they affect our health directly or indirectly through the food chain?

Once these ultrafine particles are released, there is no way to retrieve them. They are invisible and undetectable. It would, therefore, be necessary to address their environmental impact and weigh the benefit and potential risk carefully before use.

CONCLUSION

Although the lack in toxicological data of engineered ultrafine particles does not allow for adequate risk assessment, we cannot stop the progress of nanotechnology by simply believing that all engineered nano particles are too risky and harmful. On the other hand, the government and regulatory agencies do not consider nanotechnologically converted substances to be different from its conventional substance. This simply reflects the lack of people in the regulatory agencies who have the first hand knowledge in nanotechnology to realize that the nanonising of a substance may render it extra toxic in comparison to its original size.

Under such circumstances, we as nano product producers should be more cautious and we call upon the government to support and hasten research in universities and institutions in order to increase our data base from more intensive sub-cellular and ecotoxicological studies of nano particles, so as to enable us to perform proper scientific risk assessment before the release of a nano base product. We also have to strive for the establishment of a correct procedure for the risk management on these products because we cannot live with too many of such mistakes.