Tuesday Nov 26, 2013 (foodconsumer.org) -- Titanium dioxide nanomaterial is commonly used in cosmetic products and food products although it has not been proved to be safe to use and quercetin or idebenone supplements can help ameliorate the reno-toxicity of the artificial nanoparticles.  A new study in Journal of Oleo Science suggests that the artificial nanoparticles can cause damage to the kidneys.

N. M. Al-Rasheed from Pharmacology Department, Faculty of Pharmacy, King Saud University and colleagues conducted the study and found ingestion of titanium dioxide nanoparticles induced drastic changes in many biomarkers indicating renal damage.

For the study, titanium dioxide nanoparticles were orally administered in a dose of 600 mg or 1000 mg per kg of body weight for five consecutive days and a range of kidney function biomarkers were measured.

The ingestion of titanium dioxide nanoparticles increased serum kidney function biomarkers including urea, creatinine and uric acid and serum immuno-inflammatory biomarkers including interleukin-6 (IL-6), tumor necrosis factor- α (TNF-α), vascular endothelial growth factor (VEGF, angiogenic factor), C-reactive protein (CRP), immunoglobin g (IGg), and nitric oxide (NO) while decreasing endogenous antioxidant glutathione in the kidneys.

The high dose of titanium nanoparticles resulted in greater increase in these biomarkers.  The kidney damage can also be seen when kidney tissue was subject to histological examination.

When titanium dioxide nanoparticles were co-administered with either quercetin or idebenone in a dose of 200 mg per kg body weight daily for three weeks significantly reduced the harmful effects of the nanoparticles in both doses.

Both quercetin and idebenone have a prophylactic effect on the toxicity of titanium dioxide nanoparticles.

The study conclude "The data showed the severity in renotoxicity of TiO2-NPs (titanium dioxide nanoparticles) was dose-dependent and the protective effect of quercetin and idebenone may be related to their antioxidant and anti-inflammatory properties."

This is not the one and only study that demonstrates the toxicity of nanoparticles.  Previous studies suggest that nanoparticles can get into cells and disrupt DNA, potentially causing DNA mutation and cancer development.  Studies also show that fish exposed to high doses of nanoparticles died.

A few dietary supplements manufacturers and retailers have stopped making or selling products with titanium dioxide.  But this nanomaterial is still commonly used in dietary supplements, cosmetic products and food products.

Another commonly used artificial nanomaterial is silicon dioxide.  No evidence suggests that silicon dioxide nanoparticles are safer than titanium dioxide.

A person eating a normal diet may not ingest so much of nanoparticles each day.  But that does not indicate that a lower dose is safe even though it must be safer. (David Liu, PHD)