Cleaning cat litter is not a job for the faint of heart. The smell alone can leave your eyes watering. However, as unpleasant a job it is, you shouldn't take shortcuts by pouring cat litter into a toilet. Although at first, you won't notice any issues, in time, the buildup of cat litter and cat feces in your toilet will cause a blockage.
Most Cat Litter Is Made of Clay
Pipes burst for all sorts of reasons. Perhaps you have faced a cold snap and the resulting sub-zero temperatures have made ice form inside the pipe, causing it to expand. Maybe the water pressure to your home or work premises is too high and the joints in your plumbing system have faced too much strain. There again, you might simply have an old section of pipework which has deteriorated over the years until it has finally allowed water to escape.