The worries over nanoparticles are understandable. One study found that when mice were exposed to nanoparticles their drinking water at concentrations up 50 times what humans experience on average - it impacted good bacteria within gut walls. But this was only after being given an extremely high daily dose; we don't know how much people would be afflicted by these particles without continued exposure over time or how different types react with our bodies differently.
The concern over nanoparticles in sunscreen applied topically to the skin was raised in 2013 when workers installing roofing products showed signs of premature weathering, as well as contact with car paint and other consumer products.
Should i be worried about nanoparticles in topical products like sunscreen and toothpaste?
Campaigners are warning that new research into the safety of nanoparticles is not enough. They point out there have been many studies that show potential health risks for these particles, but environmental groups say more work needs to be done before we can rest easy with our topical products that contain them.
Nano-particles are most often used in the form of zinc oxide to improve sunscreen protection from UVA, and in toothpaste in the form of nano-hydroxyapatite to remineralise enamel. Nanoparticles such as these, when applied repeatedly over time can damage living cells and organs due to their size; they're too small for our body's natural immune system or enzymes that break down harmful molecules like cancerous growths on skin cells!
Should i keep using products with nano particles?
It's important to do your research and decide what is right for you.
“Current research indicates that exposure via inhalation and skin contact can result in nanoparticles entering the body. Nanoparticles are tiny particles that can be inhaled or ingested and may pose a possible problem both medically and environmentally.” - News-Medical.
“The position of the Australian Therapeutic Goods Administration (TGA), based on several published papers (up to May 2013) as well as reviews of international authorities, is that nanoparticles are safe. ‘Several in vitro and in vivo studies using both animal and human skin have shown that these NPs do not penetrate the underlying layers of skin, with penetration limited to the stratum corneum. This suggests that systemic absorption is unlikely.’ A further study published in 2014 found that when exposed to zinc oxide nanoparticles, human immune cells (called macrophages) effectively absorbed the nanoparticles and broke them down. Based on current evidence, neither zinc oxide nor titanium dioxide nanoparticles are likely to cause harm when used as ingredients in sunscreens. There are more risks associated with avoiding sunscreens (sunburn, skin cancers) than those posed by nanoparticles.” - www.science.org.au
Hydroxyapatite Toothpaste (no nano particles)