Silicon dioxide particles and small intestine function in lab tests
What it found
In lab tests on human intestinal cells, tiny silicon dioxide particles changed how iron, zinc, glucose and fat were taken up, weakened the cell barrier and damaged the cell surface.
The particles clumped together in the test liquid.
What they found
Animal and lab studies
Nutrient absorption
Iron transport across the cell layer dropped after both short and long exposure. Zinc transport did not change, but zinc uptake rose after long exposure. Glucose transport rose after long exposure to medium and high doses, while fat uptake fell after long exposure to the low dose.
Barrier function
After two days of long exposure, the electrical resistance of the cell layer dropped significantly, meaning the barrier became leakier. Short exposure had no effect on resistance.
Oxidative stress and inflammation
The particles raised reactive oxygen species in the cells after both short and long exposure. Genes for the inflammatory signals IL-8, TNF-alpha and NF-kB were switched on more strongly after long exposure.
Cell surface damage
The area of the cell surface covered by tiny finger-like projections (microvilli) was significantly reduced after high short and long exposure. This shrinks the surface available for absorbing nutrients.
Alkaline phosphatase
The activity of the brush border enzyme intestinal alkaline phosphatase rose after medium short exposure and after medium and high long exposure. The authors suggest the cells may have raised it to help keep the barrier working.
Other findings
Particle clumping
In water and cell culture medium the particles clumped into larger groups, with sizes from about 219 to 1072 nm. The authors say this clumping may have stopped the particles from entering the cells.
What the authors conclude
“SiO 2 NP exposure at physiologically relevant doses ultimately caused adverse outcomes in an in vitro model.”
Also in their conclusions
- They conclude that exposure to silicon dioxide particles at doses similar to real-life intake caused harmful effects in their lab model of the small intestine.
- They say the particles affected iron, zinc, glucose and fat absorption as well as barrier function.
How it was done
Tiny silicon dioxide particles are common in food and food packaging, and the authors say the health effects of these swallowed particles are still unknown.
They grew human intestinal cells (Caco-2 and HT29-MTX) on permeable supports for 16 days to form a model of the small intestine. The cells were exposed to 30 nm silicon dioxide particles at low, medium and high doses for 4 hours (acute) or 5 days (chronic).
What it can’t tell you
- This was a lab study using human intestinal cells grown on a membrane, not people or whole animals. It cannot show what happens when someone eats food containing these particles.
- The cells were exposed to particles in liquid, without the chewing, stomach acid and food mixing that happen during normal digestion.
- The study did not measure whether the particles pass into the bloodstream, because transport across the cell layer was undetectable.
Who paid
- Funding
- Funded by NIEHS NIH HHS (from the PubMed record).
- Authors work at
- Binghamton University, USA; Soil and Nutrition Laboratory, USA
The paper
- Title
- Silicon dioxide nanoparticle exposure affects small intestine function in an in vitro model
- Type
- Study
- Evidence
- Animals and lab studies
- Summarised from
- Full text
- Cite
- Guo Z, Martucci NJ, Liu Y, Yoo E, Tako E, Mahler GJ (2018). Silicon dioxide nanoparticle exposure affects small intestine function in an in vitro model. Nanotoxicology. doi:10.1080/17435390.2018.1463407Free full textPubMed 29668341DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error