When asked about Silver, the first thought is often with
regards to the precious shiny white metal that is used in making
jewelleries. Silver, in disinfection,
refers to colloidal nanoparticles of silver that are stabilized by chelating
molecules. This can range from solutions of silver nitrate in water to silver
dihydrogen citrate that is a more stabilized form in comparison. Silver
containing disinfectants have been used extensively for topical wound
applications and other medical surface antisepsis such as catheter surfaces and
gauzes for covering burns and wounds. In addition, silver has long been used in
water treatments as an additive. In terms of its application for general
surface disinfection, in the past decade the use of silver disinfecting agents
has increased dramatically.
regards to the precious shiny white metal that is used in making
jewelleries. Silver, in disinfection,
refers to colloidal nanoparticles of silver that are stabilized by chelating
molecules. This can range from solutions of silver nitrate in water to silver
dihydrogen citrate that is a more stabilized form in comparison. Silver
containing disinfectants have been used extensively for topical wound
applications and other medical surface antisepsis such as catheter surfaces and
gauzes for covering burns and wounds. In addition, silver has long been used in
water treatments as an additive. In terms of its application for general
surface disinfection, in the past decade the use of silver disinfecting agents
has increased dramatically.
From a cleaning perspective, almost none of the
generally-used silver containing solutions has cleaning abilities better than
pure water. For use as an environmental surface disinfectant, cleaning ability
needs to be taken into consideration both for removal of soils and bioburden
from surfaces to be disinfected, but also with respect to any effect that soils
may have on the disinfection capability of the product being used.
generally-used silver containing solutions has cleaning abilities better than
pure water. For use as an environmental surface disinfectant, cleaning ability
needs to be taken into consideration both for removal of soils and bioburden
from surfaces to be disinfected, but also with respect to any effect that soils
may have on the disinfection capability of the product being used.
With respect to disinfection efficacy, silver containing
disinfectants are bactericidal, virucidal, and fungicidal and some formulations
have also been reported to show inactivation against Mycobacteria. Microbial resistance to silver containing
disinfectants have been reported in numerous studies along with detailed
descriptions of the mechanisms microbial resistance.
disinfectants are bactericidal, virucidal, and fungicidal and some formulations
have also been reported to show inactivation against Mycobacteria. Microbial resistance to silver containing
disinfectants have been reported in numerous studies along with detailed
descriptions of the mechanisms microbial resistance.
Oral administration of silver is generally considered to
induce minimal toxicity; however this can depend on the type of silver
containing compound and its concentrations. For example, extended uses of
silver containing agents on topical and nasal routes can cause Argyria, which
is a blue-grey darkening of the region’s skin.
induce minimal toxicity; however this can depend on the type of silver
containing compound and its concentrations. For example, extended uses of
silver containing agents on topical and nasal routes can cause Argyria, which
is a blue-grey darkening of the region’s skin.
Silver is considered as an environmental hazard because
of its toxicity, persistence and bioaccumulative potential. Ionic silver is
known to be one of the most toxic metal residues to aquatic organisms. An
example could be silver nitrate, which has high aquatic toxicity at even low
concentrations. Silver nanoparticles could enter the sewage plants and
seriously challenge the biological purification process during water treatment.
Soils and waters contaminated with silver ions are often viewed as low in
concentration when compared to other metal ions present; however silver is a
rare metal in nature and thus its perceived low concentrations are still higher
than its natural safe concentration in nature. Ultimately, silver’s toxicity to
living organism is limited by the exposure concentration and bioavailability.
The uptake level of silver ions, or silver containing compounds, by the
organisms’ cells is highly influenced by the form of silver.
of its toxicity, persistence and bioaccumulative potential. Ionic silver is
known to be one of the most toxic metal residues to aquatic organisms. An
example could be silver nitrate, which has high aquatic toxicity at even low
concentrations. Silver nanoparticles could enter the sewage plants and
seriously challenge the biological purification process during water treatment.
Soils and waters contaminated with silver ions are often viewed as low in
concentration when compared to other metal ions present; however silver is a
rare metal in nature and thus its perceived low concentrations are still higher
than its natural safe concentration in nature. Ultimately, silver’s toxicity to
living organism is limited by the exposure concentration and bioavailability.
The uptake level of silver ions, or silver containing compounds, by the
organisms’ cells is highly influenced by the form of silver.
Here’s how we would score silver-based disinfectants on
the key decision making criteria:
the key decision making criteria:
• Speed of
Disinfection – B to C
Disinfection – B to C
o Contact times
range from minutes to hours depending on the type of silver-containing solution
used
range from minutes to hours depending on the type of silver-containing solution
used
• Spectrum of
Kill – B to C
Kill – B to C
o Silver
disinfectants can kill a selection of bacteria, virus, and fungi; however
performance in this criteria is tied to type of silver-containing solution
disinfectants can kill a selection of bacteria, virus, and fungi; however
performance in this criteria is tied to type of silver-containing solution
o Some
nanoparticle solutions have shown the ability to provide residual activity on
surfaces
nanoparticle solutions have shown the ability to provide residual activity on
surfaces
• Cleaning
Effectiveness – D
Effectiveness – D
o Most
formulations do not contain surfactants making their cleaning efficacy no
better than water
formulations do not contain surfactants making their cleaning efficacy no
better than water
• Safety Profile
– C - D
– C - D
o Silver is
generally considered to induce minimal toxicity; however this is dependent upon
the type of silver containing compound, its concentrations and bioavailability.
generally considered to induce minimal toxicity; however this is dependent upon
the type of silver containing compound, its concentrations and bioavailability.
o Ionic Silver
is one of the most toxic metal residues to aquatic organisms
is one of the most toxic metal residues to aquatic organisms
• Environmental
Profile – D
Profile – D
o Silver is
considered as an environmental hazard because of its toxicity, persistence and
bioaccumulative potential
considered as an environmental hazard because of its toxicity, persistence and
bioaccumulative potential
• Cost
Effectiveness – B to C
Effectiveness – B to C
o Cost is
dependent on the formulation of the
disinfectant and thus the concentration at which silver ions are used.
dependent on the formulation of the
disinfectant and thus the concentration at which silver ions are used.
**For more in-depth scientific information about Alcohol
and other disinfectant chemistries, stay tuned to www.infectionpreventionresource.com .
and other disinfectant chemistries, stay tuned to www.infectionpreventionresource.com .
Bugging Off
Nicole
