The diaphragm helps in the flow of the air to and from the lungs. The diaphragm moves down as one inhales, and then up as one exhales. The movement is controlled by the phrenic nerves. Whenever there is irritation on these nerves, it induces diaphragm spasm.
Titanium dioxide is used as a UV filter in sunscreen products to protect the skin from harmful UV rays when exposed to sunlight.
Exposure to titanium often happens by way of titanium compounds that are added to cosmetics, sunscreens, paints, and food. Titanium dioxide nano particles is usually the compound in question and safety concerns have been expressed.