Researchers at the University of Utah, Department of Pharmacotherapy, have studied the effects of commercially available colloidal silver in healthy volunteers between 18 and 80 year of age.
Testing of Colloidal Silver
Previously, testing of colloidal silver has been performed by in vitro testing (work performed outside of a living organism), and it was considered important to understand whether in vitro findings would translate to in vivo (research done within an entire living organism) findings in relation to possible toxicity. The results indicate that no detectable toxicity was seen in various comprehensive assays and tests for 10 ppm colloidal silver at a daily ingestion rate of 100 µg/day
To minimise risk to study subjects, a dose-time escalation dosing scheme was employed. Study one used 10 ppm oral silver particle dosing with 3-, 7-, and 14-day time periods. After the completion of each time period, an independent Data Safety and Monitoring Board (DSMB) reviewed every measurement for evidence of toxicity.
No clinically important changes in metabolic, hemotalogic, urinalysis measures were identified. No morphological changes were detected in the lungs, heart or abdominal organs. No significant changes were noted in pulmonary reactive oxygen species or pro-inflammatory cytokine generation.
Nanoscale colloidal silver is an increasingly deployed engineered nanomaterial, with potential nutraceutical and therapeutic properties, increasingly found in consumer product and medical devices. The study demonstrates that 14-day monitored human oral dosing of a commercial oral nanoparticle silver colloidal product does not produce observable clinically important toxic effects.