Particles have infinite render distance. They are rendered, regardless of which way they're facing and how far away they are from the particle. This hurts performance unnecessarily, especially if multiple people are playing on a world/realm/server and a person loads an area with lots of high resolution particles.

Attached are screenshots of a demonstration of infinite particle render distance. A fog remover resource pack was used to make the results more visible, along with a custom particle resource pack.

Screenshot 1 shows what was used to test the bug. The repeating command block contained a /particle command, summoning a large particle every 10 ticks. The command block was in a ticking area.

Screenshot 2 shows the same area, but from such a distance that the zombie entities are not rendered. The particle is still rendered and visible.

Screenshot 3 shows the same area, but from such a distance that the particle is starting to get obscured by fog. The particle is still rendered and visible.

Screenshot 4 shows the same area, but from over 300 blocks away and well out of render distance. The particle is still rendered in its entirety, only it's obscured by fog. The particle is still rendered and visible.

Screenshot 5 shows that the render distance is set to 12 chunks.

This bug was experienced on Windows 10 devices too, with considerable lag when large amounts of particles were spawned out of render distance.