Rinkaichū (燐壊虫, Literally meaning: Phosphorus Destruction Insect) are a breed of nano-sized, venomous insects (ナノサイズの毒蟲, nanosaizu no dokumushi, English TV: Nano-sized Venomous Beetles) hosted by a select few members of the Aburame clan. These bugs destroy their enemies' cells, causing excruciating pain in the process.
Unlike the standard kikaichū, which are able to act independently of the user, the nano-sized insects can seemingly only be transferred onto a victim's body by direct physical contact; though only a mere touch from the user's skin is required as the bugs can circumvent most forms of clothing. However, this apparently does not apply to the user's own clothes, who must instead remove items in order to effectively increase their chances of hitting the target.
The rinkaichū are akin to viruses, spreading rapidly and multiplying as they thrive on living cells. They require living flesh to survive on, and will die shortly if their hosts do, or if they leave a body for a period of time.
The two known users of these bugs: Torune Aburame and Shikuro Aburame, are also the only known Aburame to possess the antibodies for the insects. These insects are considered to be rare, even amongst the Aburame clan.
- In the anime, Shino bred the poisonous insects, feeding them with his insects. After many years, and generations of insects, some insects with antibodies against the poisonous insects were born.