99.99 percent of the speed of light is very slow compared to ultra-high-energy cosmic rays that have already been hitting the earth for billions of years. The fastest detected ones are on the order of 99.999999999999999999995% c. That gives a single nucleon the momentum of a baseball thrown at 60 mph. If those haven’t created earth-sucking black holes then the LHC certainly won’t. There’s also two or three other reasons why the possibility can be dismissed. Hawking radiation being one: any micro black hole would almost instantly evaporate the moment it is created. Another: collisions at nearly the speed of light also rebound at that speed, so a black hole will fly through the earth and into space in a split second. Also, a black hole the mass of only a few atoms is not likely to accumulate more mass very quickly anyway.