I just read that it has been revealed that Dunkin' Donuts in America contains titanium dioxide nano particles to whiten the dough. Nano particles can be absorbed more easily into cells. Can we assume the Dunkin' Donuts in Thailand contain the same?

Of course.

But just a few days ago Dunkin in the States announced they would stop using it when some celebrity called them on it.

"However, there is no clear evidence that titanium dioxide is harmful to humans, and the U.S. Food and Drug Administration (FDA) says as long as the colorant does not amount to 1% of any product, a label is not mandatory.

“The ingredient used in our powdered donuts does not meet the definition of ‘nanomaterial’ as outlined under FDA guidance,” a Dunkin’ Donuts spokesperson told the Huffington Post.

“Nevertheless, we began testing alternative formulations for this product in 2014 and we are in the process of rolling out a solution to the system that does not contain titanium dioxide.”"

TIME

Some people would try to filter D-limonene, a solvent used in various household chemicals such as wood conditioners for furniture, paint strippers, cleaners and hand soaps from natural orange juice.