Overload

Silver poisoning

Category: Illness or disabilities

Type

Involuntary

Introduction and description

 

Silver is a metallic element with symbol Ag and atomic number 47. The symbol Ag stems from Latin argentum, derived from the Greek ὰργὀς (literally "shiny" or "white").

It is a soft, white, lustrous transition metal, and exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal.

The metal is found in the Earth's crust in the pure, free elemental form ("native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a by product of copper, gold, lead, and zinc refining. Silver is more abundant than gold, but it is much less abundant as a native metal.

Medically, silver has been found to be toxic to some bacteria.  In this capacity it has thus found a use in vitro [external to the body].  Just as Copper-alloy touch surfaces have been found to have natural intrinsic properties to destroy a wide range of microorganisms (e.g., E. coli O157:H7, methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus, Clostridium difficile, influenza A virus, adenovirus, and fungi), so silver is a natural anti-bacterial agent.  Not an anti-biotic, an anti-bacterial agent for external use.  But as we shall see, even this application has its problems.

The Problems with silver

 

Toxicity to humans and other animals

The principle problem in relation to silver is the completely erroneous belief that silver if ingested is an antibiotic – or as it is sometimes promoted a ‘natural antibiotic’. 

And it isn’t, it is poisonous. 

There are two main types of silver that are causing concern in relation to health. 

  • Silver nanoparticles - The use of Silver and silver nanoparticles in healthcare, domestic and many other applications is an extreme cause of concern.  Nanoparticles are proving to be a problem in general, not just silver nanoparticles.
  • Colloidal silver - The other problem area is the promotion by some so-called ‘health companies’ of colloidal silver.

Colloidal silver (a colloid consisting of silver particles suspended in liquid) and formulations containing silver salts were used by physicians in the early 20th century. 
This is no recommendation. 
Physicians then, were as gung-ho about administering poisonous products as they are now.  The early 20th century saw doctors happily using mercury to treat syphilis for example, hence it is no wonder this stuff was discontinued in the 1940s. 
But, since the 1990s, colloidal silver has again been marketed as an ‘alternative’ medicine, often with extensive "cure-all" claims. Colloidal silver products remain available in many countries as ‘dietary supplements’, although they are not effective in treating any known condition and carry the risk of both permanent cosmetic side effects such as argyria and more serious ones such as death.  We will look at these problems under the heading of Symptoms.

Toxicity to the Environment

 

There are additional problems.  Most of Nature is dependent on a complex web of micro-organisms, many of which are bacteria. 

Simply put, the release of so much silver in particle form into the environment is a major threat to all benign soil organisms. 

We could be facing an ecological disaster of catastrophic proportions by dumping so much silver into the sea, lakes, rivers and on land.

Symptoms

Whether ingested or inhaled, silver has the capability of damaging the heart, the brain – causing brain damage [dementia, autism, bipolar disorder, schizophrenia etc], the skin, the reproductive organs, the thyroid glands and other endocrine glands, the liver, the stomach, the intestine [where it attacks the natural fungal and bacterial flora of the intestine and thus leads on to IBS etc], the lungs, the blood circulatory system as a whole, and so on and so on, for example:

Orally administered silver has been described to be absorbed in a range of 0.4-18% in mammals with a human value of 18%. Based on findings in animals, silver seems to be distributed to all of the organs investigated, with the highest levels being observed in the intestine and stomach. In the skin, silver induces a blue-grey discoloration termed argyria. Excretion occurs via the bile and urine. The following dose-dependent animal toxicity findings have been reported: death, weight loss, hypoactivity, altered neurotransmitter levels, altered liver enzymes, altered blood values, enlarged hearts and immunological defects. Substantial evidence exists suggesting that the effects induced by particulate silver are mediated via silver ions that are released from the particle surface.   PMID:  24231525

Kidney damage

 

Although this study showed no effects on the bone marrow, it showed kidney damage:

The antibacterial effect of silver nanoparticles has resulted in their extensive application in health, electronic, and home products. However, while the population exposed to silver nanoparticles continues to increase with ever new applications, silver nanoparticles remain a controversial research area as regards their toxicity to biological systems. In particular, the oral toxicity of silver nanoparticles is of particular concern to ensure public and consumer health. Accordingly, this study tested the oral toxicity of silver nanoparticles (60 nm) over a period of 28 days in Sprague-Dawley rats ….the present results suggest that silver nanoparticles do not induce genetic toxicity in male and female rat bone marrow in vivo. Nonetheless, the tissue distribution of silver nanopaticles did show a dose-dependent accumulation of silver content in all the tissues examined. In particular, a gender-related difference in the accumulation of silver was noted in the kidneys, with a twofold increase in the female kidneys when compared with the male kidneys.  PMID: 18444010

Liver damage

 

This study reaffirmed the finding above of kidney damage, but also found extensive liver damage:

The antibacterial effect of silver nanoparticles has resulted in their extensive application in health, electronic, consumer, medicinal, pesticide, and home products; however, silver nanoparticles remain a controversial area of research with respect to their toxicity in biological and ecological systems…. This study tested the oral toxicity of silver nanoparticles (56 nm) over a period of 13 weeks (90 days) in F344 rats …. There was a significant decrease (P < 0.05) in the body weight of male rats after 4 weeks of exposure, ….. Histopathologic examination revealed a higher incidence of bile-duct hyperplasia, with or without necrosis, fibrosis, and/or pigmentation, in treated animals. There was also a dose-dependent accumulation of silver in all tissues examined. … The target organ for the silver nanoparticles was found to be the liver in both the male and female rats.  PMID:  20691052

Lung and liver damage [from inhalation]

 

The subchronic inhalation toxicity of silver nanoparticles was studied in Sprague-Dawley rats. …The animals were exposed to silver nanoparticles (average diameter 18-19 nm) for 6 h/day, 5 days/week, for 13 weeks in a whole-body inhalation chamber. In addition to mortality and clinical observations, body weight, food consumption, and pulmonary function tests were recorded weekly. At the end of the study, the rats were subjected to a full necropsy, blood samples were collected for hematology and clinical chemistry tests, and the organ weights were measured. Bile-duct hyperplasia in the liver increased dose dependently in both the male and female rats. Histopathological examinations indicated dose-dependent increases in lesions related to silver nanoparticle exposure, including mixed inflammatory cell infiltrate, chronic alveolar inflammation, and small granulomatous lesions. Target organs for silver nanoparticles were considered to be the lungs and liver in the male and female rats. PMID:  19033393

Lung and blood circulatory system damage [from ingestion]

 

This interesting study showed that damage to the lungs is possible even if the silver particles are ingested and not inhaled

Blood levels, tissue distributions, and excretion of silver (Ag) were measured in male Sprague-Dawley rats (n = 5) up to 24 h after a single oral administration of silver nanoparticles (AgNP) and silver ions (Ag(+)), respectively. …. Tissue distribution of Ag in liver, kidneys, and lungs was higher when Ag(+) was administered compared to AgNP. Orally administered AgNP were predominantly excreted through feces, suggesting low bioavailability. … decreased red blood cell counts, hematocrit, and hemoglobin were found in the Ag(+)-treated groups, while increased platelet counts and mean platelet volume were noted in the AgNP-treated rats. PMID:  24283396

Brain and blood brain barrier damage

Military personnel are often subjected to sleep deprivation (SD) during combat operations and the researchers here attempted to show that a wider model of stress in general could result in brain damage and BBB breakdown. In effect, since SD produces severe stress and alters neurochemical metabolism in the brain, a possibility exists that acute or long-term SD will influence blood-brain barrier (BBB) function and brain pathology. But they found out a bit more which is very interesting:

 

This hypothesis was examined in young adult rats (age 12 to 14 weeks) using an inverted flowerpot model. Rats were placed over an inverted flowerpot platform (6.5 cm diameter) in a water pool where the water levels are just 3 cm below the surface. In this model, animals can go to sleep for brief periods but cannot achieve deep sleep as they would fall into water and thus experience sleep interruption. These animals showed leakage of Evans blue in the cerebellum, hippocampus, caudate nucleus, parietal, temporal, occipital, cingulate cerebral cortices, and brain stem. The ventricular walls of the lateral and fourth ventricles were also stained blue, indicating disruption of the BBB and the blood-cerebrospinal fluid barrier (BCSFB). Breakdown of the BBB or the BCSFB fluid barrier was progressive in nature from 12 to 48 h but no apparent differences in BBB leakage were seen between 48 and 72 h of SD.
Interestingly, rats treated with metal nanoparticles, e.g., Cu or Ag, showed profound exacerbation of BBB disruption by 1.5- to 4-fold, depending on the duration of SD.   PMID:  26133300

The possibility that diabetes aggravates nanoparticles induced blood-brain barrier (BBB) breakdown, edema formation and brain pathology was examined by these researchers, who found that indeed, diabetes hastens the brain damage .

Engineered nanoparticles from metals Ag and Cu (50-60 mn) were administered …once daily for 7 days in normal and streptozotocine induced diabetic rats. On the 8th day, BBB permeability to Evans blue and radioactive iodine (131I-sodium) was examined in 16 brain regions. …. Nanoparticles treatment in diabetic rats showed much more profound disruption of the BBB to Evans blue albumin (EBA) and radioiodine in almost all the 16 regions examined as compared to the normal animals. In these diabetic animals reduction in regional cerebral blood flow (CBF) was more pronounced than in normal rats. Edema development as seen using water content and increase in Na+ and a decrease in K+ ion were most marked in diabetic rats as compared to normal rats after nanoparticles treatment. Cell changes in the regions of BBB disruptions were also exacerbated in diabetic rats compared to normal group after nanoparticles treatment. PMID:  21121280

Skin and spleen damage

 

This paper describes the results of tests to see if nanosilver was capable of being absorbed through the skin [dermal] and if so what damage it could do

In this study, we analyzed the potential toxicity of colloidal nanosilver in acute and subchronic guinea pigs. ….. For toxicological assessments, male guinea pigs weighing 350 to 400 g were exposed to two different concentrations of nanosilver (1000 and 10,000 μg/mL) in an acute study and three concentrations of nanosilver (100, 1000, and 10,000 μg/mL) in a subchronic study. … In all experimental animals the sites of exposure were scored for any type of dermal toxicity and compared with negative control and positive control groups. In autopsy studies during the acute test, no significant changes in organ weight or major macroscopic changes were detected, but dose-dependent histopathologic abnormalities were seen in skin, liver, and spleen of all test groups. In addition, experimental animals subjected to subchronic tests showed greater tissue abnormalities than the subjects of acute tests. It seems that colloidal nanosilver has the potential to provide target organ toxicities in a dose- and time-dependent manner.  PMID:  21720498

Heart and bone damage

 

This additional paper also describes the results of tests to see if nanosilver was capable of being absorbed through the skin [dermal] and if so what damage it could do:

Present study compares the tissue levels of Ag NPs in different organs of guinea pigs quantitatively after dermal application and analyses the morphological changes and pathological abnormalities on the basis of the Ag NPs tissue levels. …. For toxicological evaluation, male guinea pigs were exposed to three concentrations of Ag NPs (100, 1000 and 10000 ppm) according to acute pretests for further assessments in subchronic model in a period of 13 weeks. …A close correlation between dermal exposure and tissue levels of Ag NPs was found (p < 0.05) and tissue uptakes happened in dose dependent manner with the following ranking: kidney>muscle>bone>skin>liver>heart >spleen. In histopathological studies, severe proximal convoluted tubule degeneration and distal convoluted tubule were seen in the kidneys of the middle and high-dose animals. Separated lines and marrow space narrow were determined as two major signs of bone toxicities which observed in three different dose levels of Ag NPs. Increased dermal dose of Ag NPs caused cardiocyte deformity, congestion and inflammation. The three different Ag NPs concentration gave comparable results for several endpoints measured in heart, bone and kidney, but differed in tissue concentrations and the extent of histopathological changes. It seems that Ag ions could be detected in different organs after dermal exposure ,which has the potential to provide target organ toxicities in a time and dose dependent manner.   PMID: 24250657

Colon and liver damage

 

This study evaluated two widely used in vitro cell culture models, human liver HepG2 cells and human colon Caco2 cells, as tools for assessing the potential cytotoxicity of food- and cosmetic-related nanoparticles. The two cell culture models were utilized to compare the potential cytotoxicity of 20-nm silver. The average size of the silver nanoparticle determined by our transmission electron microscopy (TEM) analysis was 20.4 nm. The dynamic light scattering (DLS) analysis showed no large agglomeration of the silver nanoparticles…. Our ICP-MS and TEM analysis demonstrated the uptake of 20-nm silver by both HepG2 and Caco2 cells. …
Significant concentration-dependent cytotoxicity of the nanosilver in HepG2 cells was observed in the concentration range of 1 to 20 µg ml(-1) and at a higher concentration range of 10 to 20 µg ml(-1) in Caco2 cells compared with the vehicle control. A concentration-dependent decrease in dsDNA content was observed in both cell types exposed to nanosilver but not controls, suggesting an increase in DNA damage. ….A concentration-dependent decrease in mitochondria membrane potential in both nanosilver exposed cell types suggested increased mitochondria injury compared with the vehicle control. …… Our results suggest that cellular oxidative stress did not play a major role in the observed cytotoxicity of nanosilver in HepG2 and Caco2 cells and that a different mechanism of nanosilver-induced mitochondrial injury leads to the cytotoxicity.
The HepG2 and Caco2 cells used in this study appear to be targets for silver nanoparticles. The results of this study suggest that the differences in the mechanisms of toxicity induced by nanosilver may be largely as a consequence of the type of cells used.
Published 2014. This article is a U.S. Government work and is in the public domain in the USA.  PMID: 24522958

Cytotoxicity

A cytotoxic agent is any agent or process that kills cells. Chemotherapy and radiotherapy are forms of cytotoxic therapy. They kill cells. The prefix cyto- denotes a cell.

…. The dimension of silver nanoparticles is close to silver ions and some reports have proved that they could translocate in body, so it is suggested that silver nanoparticles should induce the same toxicity with silver ions. …. silver nanoparticles have shown cytotoxicity in some experiment in vitro. But the mechanisms of its cytotoxity are not clear; it may attribute to the silver ions that release from silver nanoparticles or to the silver nanoparticles that permeate through cell membrane. Hence, there are some potential anxieties for the biological safety of silver nanoparticles.  PMID:  18788318

DNA damage

 

Nanoparticles can potentially cause adverse effects on organs, tissue, cell levels, and protein levels because of their physicochemical properties. Silver nanoparticles (AgNPs) are being used on a wide scale in world consumer markets; their potential hazards for humans remain largely unknown. …. Apoptosis … in liver tissue and DNA strand breaks… in lymphocytes revealed that a concentration of 78 mg of AgNPs per kg body weight can cause significant apoptosis and DNA damage. …. Significantly more alterations were induced in the hepatocytes of animals exposed to AgNP doses than in the control animals. PMID: 25674004

Immune system destruction

Macrophages are the large white blood cells, occurring principally in connective tissue and in the bloodstream, that ingest foreign particles and infectious microorganisms by phagocytosis.  In other words, since silver nanoparticles are cytotoxic to these cells, they destroy our immune systems

…The cytotoxicity of the prepared nanosilver with respect to murine macrophages is assessed in vitro because these cells are among the first to confront nanosilver upon its intake by mammals. ….. Smaller nanosilver particles release or leach larger fractions of their mass as Ag⁺ ions upon dispersion in water. This strongly influences the cytotoxicity of the nanosilver when incubated with murine macrophages. The size of the nanosilver dictates its mode of cytotoxicity (Ag⁺ ion-specific and/or particle-specific). The toxicity of small nanosilver (<10 nm) is mostly mediated by the released Ag⁺ ions. The influence of such ions on the toxicity of nanosilver decreases with increasing nanosilver size (>10 nm). Direct silver nanoparticle-macrophage interactions dominate the nanosilver toxicity at sizes larger than 10 nm.  PMID:  23418027

 

Causes/Sources

Where is silver used?  Where does it come from and how can it accumulate, by ingested or breathed in?

Dental fillings

Silver is used in two sorts of dental fillings – amalgam fillings and in some specialised precious metal alloys.:

  • Amalgam  - is an alloy of mercury (50%), silver (~22-32% ), tin (~14%), copper (~8%), and other trace metals.
  • Precious metallic alloys – normally  use gold (high purity: 99.7%) and gold alloys (with high gold content), but there is also silver-palladium alloy

If these fillings leak or are old, or you suffer from teeth grinding, then nanoparticles of silver may be leaching into the body.

 

Food

An observation has been provided providing fuller details - Toxic nanoparticles and the human food chain – but in brief, silver is used in farming and thus enters the food chain.  For example, farmers have used silver nanoparticles as a pesticide :

Lin and his colleagues, including MU scientists Azlin Mustapha and Bongkosh Vardhanabhuti, studied the residue and penetration of silver nanoparticles on pear skin. First, the scientists immersed the pears in a silver nanoparticle solution similar to pesticide application. The pears were then washed and rinsed repeatedly. Results showed that four days after the treatment and rinsing, silver nanoparticles were still attached to the skin, and the smaller particles were able to penetrate the skin and reach the pear pulp.

But there is a much more sinister addition to this, as it appears that nanoparticles are being added to food

The use of silver nanoparticles in food, food contact materials, dietary supplements and cosmetics has increased significantly owing to their antibacterial and antifungal properties. As a consequence, the need for validated rapid screening methods to assess their toxicity is necessary to ensure consumer safety.
Published 2014. This article is a U.S. Government work and is in the public domain in the USA.  PMID: 24522958

One would have thought that the tests for safety should have been completed before they were added, but it would seem this is not the case.

Medical equipment

Silver is used in some urinary catheters (where tentative evidence indicates it reduces catheter-related urinary tract infections) and in endotracheal breathing tubes (where evidence suggests it reduces ventilator-associated pneumonia). The silver ion (Ag+) is bioactive and in sufficient concentration readily kills bacteria in vitro [external to the body]. BUT, there are worries about this approach:

…. some reports have proved that many medical devices loaded with silver could release silver ions (Ag+) which could translocate in blood circulation and cumulate in some organs such as liver and kidney. It may induce hepatotoxicity or renal toxicity and may lead to death in some situation extremely exposed to a certain dose of Ag+. PMID:  18788318

So, here there is justifiable caution about employing medical devices inside the body.

Bandages and wound dressings

Dilute silver nitrate solutions and other silver compounds are used as disinfectants and added to bandages and wound-dressings.  Wound dressings containing silver sulfadiazine are used to treat external infections. The use of such dressings has become more widespread as a consequence of antibiotic resistance to microorganisms, which has gradually become one of the major problems faced in the field of wound care in burns patients.  But a burn or an open wound is a point of entry into the body and there is some concern that the use of Silver nanoparticles may not be safe, they are effective at promoting wound healing, but may not be safe in the long term as the particles seep into the body:

We aimed in present study to test the release of nanosilver from nanosilver wound dressing and compare the dermal and systemic toxicity of nanosilver dressings in a repeated dose (21 days) model. Under general anaesthesia, a limited standard 2nd degree burns were provided on the back of each rat in all treatment, negative control (simple dressing) and 5% silver nitrate groups, each contained 5 male wistar rats. According to the analysis made by atomic absorption spectrometry, the wound dressings released 0.599 ± 0.083 ppm of nanosilver during first 24 hrs of study. Daily observations were recorded and wounds were covered with new dressings each 24 hrs. Burn healing was observed in nanosilver wound dressing group in shorter time periods than the control groups. In toxicity assessment, this dressing didn't cause any hematological and histopathological abnormalities in treatment group but biochemical studies showed significant rise of plasma transaminase (ALT) at the endpoint (21 days) of the study (P=0.027). Portal mononuclear lymphoid and polymorphonuclear leukocyte infiltrations in three to four adjacent foci were recognized around the central hepatic vein in treatment group. Mild hepatotoxic effects of nanosilver wound dressing in wistar rat emphasize the necessity of more studies on toxicity potentials of low dose nanosilver by dermal applications.  PMID:  23690097

Cosmetics and sunscreens

Given that silver nanoparticles can be absorbed via the skin and cause skin damage and then organ damage, it is rather chilling to know they are used in a number of cosmetics

“Silver nanoparticles (Ag NPs) have been widely used as new potent antimicrobial agents in cosmetic and hygienic products.

And it would appear, in sunscreens:

Nanotechnology is rapidly growing with nanoparticles produced and utilized in a wide range of commercial products throughout the world. For example, silver nanoparticles (Ag NP) are used in electronics, bio-sensing, clothing, food industry, paints, sunscreens, cosmetics and medical devices. …. A large number of in vitro studies indicate that Ag NPs are toxic to the mammalian cells derived from skin, liver, lung, brain, vascular system and reproductive organs. Interestingly, some studies have shown that this particle has the potential to induce genes associated with cell cycle progression, DNA damage and apoptosis in human cells at non-cytotoxic doses. Furthermore, in vivo bio-distribution and toxicity studies in rats and mice have demonstrated that Ag NP administered by inhalation, ingestion or intra-peritoneal injection were subsequently detected in blood and caused toxicity in several organs including brain. PMID:  20719239

Incinerators

The National Health Services in the UK spent about 25 million pounds on silver-containing dressings in 2006. Silver-containing dressings represent about 14% of the total dressings used and about 25% of the overall wound dressing costs.  Medical waste is usually incinerated, meaning that all this silver is being spewed onto the surrounding area of each incinerator.

Clothing

Silver inhibits the growth of bacteria and fungi on clothing (such as socks) and is sometimes added to reduce odours and the risk of bacterial and fungal infections. It is incorporated into clothing or shoes either by integrating silver nanoparticles into the polymer from which yarns are made or by coating yarns with silver. The loss of silver during washing varies between textile technologies, and the effect on the environment is ‘not yet known’, in other words, it has not been evaluated. 

Cloud seeding

Much the same problem occurs from cloud seeding.  Cloud seeding is a form of weather modification, is a way of changing the amount or type of precipitation that falls from clouds, by dispersing substances into the air that serve as cloud condensation or ice nuclei, which alter the microphysical processes within the cloud. The usual intent is to increase precipitation.

Wikipedia
With an NFPA 704 health hazard rating of 2, silver iodide can cause temporary incapacitation or possible residual injury to humans and mammals with intense or continued but not chronic exposure.
Several detailed ecological studies have concluded there is ‘negligible environmental and health impacts’.  But the people doing the studies were often not entirely unbiased and the cumulative effect of silver emissions has not been assessed.
Cloud seeding over Kosciuszko National Park [Australia]—a biosphere reserve—is problematic in that several rapid changes of environmental legislation were made to enable the trial. Environmentalists are concerned about the uptake of elemental silver in a highly sensitive environment affecting the pygmy possum among other species as well as recent high level algal blooms in once pristine glacial lakes.

Pollution in general

 "In 1978, an estimated 2,740 tonnes of silver were released into the US environment. This led the US Health Services and EPA to conduct studies regarding the potential for environmental and human health hazards related to silver. These agencies and other state agencies applied the Clean Water Act of 1977 and 1987 to establish regulations on this type of pollution."  So these two bodies at least consider unregulated emission of silver into the environment to be a health hazard and an environmental one.

Pharmaceuticals

 

Early application of nanotechnology-enabled products involved drug reformulation to deliver some otherwise toxic drugs (e.g., antifungal and anticancer agents) in what the medical profession called ‘a more effective manner’.   But there is every intention of rolling out nanotechnology in an even more aggressive way.
The clinical use of combined imaging and ‘therapeutic’ nanodevices was estimated to start occurring around 2020; and changes in the way disease is diagnosed, treated and monitored using this symptom based model and extensive use of nanotechnology was anticipated.

Government

In their headlong rush to use any untested technology promoted by pharmaceutical companies and other chemical companies to solve problems which are better solved by addressing the cause as opposed to the symptoms, governments, health agencies, even charities are funding and releasing these toxins into the environment in ever increasing amounts:

 Due to continuing advances in the development of structures, devices, and systems with a length of about 1 to 100 nanometres (nm) (1 nm is one billionth of a metre), the Medical Advisory Secretariat conducted a horizon scanning appraisal of nanotechnologies as new and emerging technologies, including an assessment of the possibly disruptive impact of future nanotechnologies. The National Cancer Institute (NCI) in the United States proclaimed a 2015 challenge goal of eliminating suffering and death from cancer. To help meet this goal, the NCI is engaged in a concerted effort to introduce nanotechnology "to radically change the way we diagnose, treat and prevent cancer.  PMID: 23074489

Nanotechnology is being developed and rolled out at a spanking pace in the USA, apparently with no controls whatsoever.  The United States National Nanotechnology Initiative (NNI) is a United States federal government program for the science, engineering, and technology research and development for nanoscale projects.  At one time theoretically it was to include the ethical, legal, and cultural implications of the use of nanotechnology, but from what we have seen the only researchers that are addressing these and key safety issues are outside the USA.  And researchers outside the USA have no influence on the USA – meaning the USA poses an immense threat to both human health and environmental health in the rest of the world.

References and further reading

  • Regul Toxicol Pharmacol. 2014 Feb;68(1):1-7. doi: 10.1016/j.yrtph.2013.11.002. Epub 2013 Nov 12.  Oral toxicity of silver ions, silver nanoparticles and colloidal silver--a review.  Hadrup N1, Lam HR2.
  • Inhal Toxicol. 2008 Apr;20(6):575-83. doi: 10.1080/08958370701874663 .  Twenty-eight-day oral toxicity, genotoxicity, and gender-related tissue distribution of silver nanoparticles in Sprague-Dawley rats.  Kim YS1, Kim JS, Cho HS, Rha DS, Kim JM, Park JD, Choi BS, Lim R, Chang HK, Chung YH, Kwon IH, Jeong J, Han BS, Yu IJ.
  • Part Fibre Toxicol. 2010 Aug 6;7:20. doi: 10.1186/1743-8977-7-20.  Subchronic oral toxicity of silver nanoparticles.  Kim YS1, Song MY, Park JD, Song KS, Ryu HR, Chung YH, Chang HK, Lee JH, Oh KH, Kelman BJ, Hwang IK, Yu IJ.
  • J Toxicol Environ Health A. 2013;76(22):1246-60. doi: 10.1080/15287394.2013.849635.  Toxicokinetic differences and toxicities of silver nanoparticles and silver ions in rats after single oral administration.  Park K1.
  • Sheng Wu Yi Xue Gong Cheng Xue Za Zhi. 2008 Aug;25(4):958-61.  [Status of biological evaluation on silver nanoparticles].  [Article in Chinese]  Tang J1, Xi T.
  • Onco Targets Ther. 2015 Jan 29;8:295-302. doi: 10.2147/OTT.S77572. eCollection 2015.  In vivo DNA damaging and apoptotic potential of silver nanoparticles in Swiss albino mice.  Al Gurabi MA1, Ali D1, Alkahtani S1, Alarifi S1.
  • Int J Nanomedicine. 2014 Mar 24;9:1505-17. doi: 10.2147/IJN.S56729. eCollection 2014.  Effects of intraperitoneally injected silver nanoparticles on histological structures and blood parameters in the albino rat.  Sarhan OM1, Hussein RM2.  PMID:  24711700
  • Int J Nanomedicine. 2011;6:855-62. doi: 10.2147/IJN.S17065. Epub 2011 Apr 27.  Acute and subchronic dermal toxicity of nanosilver in guinea pig.  Korani M1, Rezayat SM, Gilani K, Arbabi Bidgoli S, Adeli S.
  • Iran J Pharm Res. 2013 Summer;12(3):511-9.  Sub-chronic Dermal Toxicity of Silver Nanoparticles in Guinea Pig: Special Emphasis to Heart, Bone and Kidney Toxicities.  Korani M1, Rezayat SM, Arbabi Bidgoli S.
  • Acta Med Iran. 2013 May 7;51(4):203-8.  Toxicity assessment of nanosilver wound dressing in Wistar rat.  Bidgoli SA1, Mahdavi M, Rezayat SM, Korani M, Amani A, Ziarati P.
  • J Appl Toxicol. 2014 Nov;34(11):1155-66. doi: 10.1002/jat.2994. Epub 2014 Feb 12.  Comparative cytotoxicity of nanosilver in human liver HepG2 and colon Caco2 cells in culture.  Sahu SC1, Zheng J, Graham L, Chen L, Ihrie J, Yourick JJ, Sprando RL.
  • Toxicol Sci. 2009 Apr;108(2):452-61. doi: 10.1093/toxsci/kfn246. Epub 2008 Nov 25.  Subchronic inhalation toxicity of silver nanoparticles.  Sung JH1, Ji JH, Park JD, Yoon JU, Kim DS, Jeon KS, Song MY, Jeong J, Han BS, Han JH, Chung YH, Chang HK, Lee JH, Cho MH, Kelman BJ, Yu IJ.
  • Small. 2013 Aug 12;9(15):2576-84. doi: 10.1002/smll.201202120. Epub 2013 Feb 18.  Toxicity of silver nanoparticles in macrophages.  Pratsinis A1, Hervella P, Leroux JC, Pratsinis SE, Sotiriou GA.
  • Mol Neurobiol. 2015 Oct;52(2):867-81. doi: 10.1007/s12035-015-9236-9. Epub 2015 Jul 2.  Sleep Deprivation-Induced Blood-Brain Barrier Breakdown and Brain Dysfunction are Exacerbated by Size-Related Exposure to Ag and Cu Nanoparticles. Sharma A1, Muresanu DF, Lafuente JV, Patnaik R, Tian ZR, Buzoianu AD, Sharma HS.
  • J Nanosci Nanotechnol. 2010 Dec;10(12):7931-45.  Diabetes aggravates nanoparticles induced breakdown of the blood-brain barrier permeability, brain edema formation, alterations in cerebral blood flow and neuronal injury. An experimental study using physiological and morphological investigations in the rat.  Sharma HS1, Patnaik R, Sharma A.
  • Clin Chim Acta. 2010 Dec 14;411(23-24):1841-8. doi: 10.1016/j.cca.2010.08.016. Epub 2010 Aug 16.  Silver nanoparticle applications and human health.  Ahamed M1, Alsalhi MS, Siddiqui MK.  1King Abdullah Institute for Nanotechnology, King Saud University, Riyadh-11451, Saudi Arabia. maqusood@gmail.com
  • Ont Health Technol Assess Ser. 2006;6(19):1-43. Epub 2006 Nov 1.  Nanotechnology: an evidence-based analysis.  Health Quality Ontario.

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