Can it be helpful to disperse diatomaceous earth to fight bedbugs? No, that's not true: Breathing in particles of diatomaceous earth can cause severe health damage like silicosis or even lung cancer, according to experts.
The claim appeared in a video (archived here) on TikTok by @user0170270600 on November 6, 2023. It began (translated from Korean to English by Lead Stories staff):
Diatomaceous earth absorbs water. If you sprinkle it in various spots, a bedbug falls into it and gets back to their home, finally all of them will be dead due to dehydration.
This is what the post looked like on TikTok at the time of writing:
(Source: TikTok screenshot taken on Wed Dec 6 15:56:37 2023 UTC)
As the outbreak of bedbugs in South Korea is considered a public health problem, people have started to look for pest control measures other than conventional pesticides. In this context, diatomaceous earth moved into the spotlight as an alternative pesticide.
However, pest control professionals and researchers told media, for example here and here, that using diatomaceous earth to kill bedbugs is highly discouraged since it can damage the human lung or other parts of the respiratory system, even though it can be efficient to kill bedbugs to a certain degree.
In an interview (archived here) with the news outlet The JoongAng, Professor Kim Ju-hyun from Seoul National University College of Medicine said:
Diatomaceous earth is not inefficient for bedbug control, but there is more harm than good. It is dangerous for the human body and still less efficient than pesticides.
Researchers have confirmed here, here and here that inhaling diatomaceous earth can cause silicosis and lung cancer, as the inhaled particles remain in the lung tissue.
