Researchers in Europe are examining a connection between Alzheimer's Disease and nano-sized particles that occur in sunscreen formulations. It is hypothesized that neuron links may be impacted by substances such as titanium dioxide which also occur in diesel fuels. Evidence from small animal studies implies causality, subject to future research.
"The brain itself is a very special organ. It cannot repair by replacing nerve cells – the ones you get at birth have to last all your life, which makes them peculiarly vulnerable to long-term, low-dose toxicity," said Dr. Vyvyan Howard, one of the lead scientists on the study.