^You guys should chill out. Not only is it off topic but it's pretty clearly a pointless argument. You are right by the way psychedelic jay, but I really don't think it's worth pursuing, at least not in such a heated way.
In response to the OP-
If by "bad for you" you mean neurotoxicity, here's what wikipedia has to say about it, it's fairly straightforward I think. PCP is an NMDA antagonist, as are ketamine and DXM. I believe PCP to be more neurotoxic then DXM and a bit more neurotoxic then ketamine. Also, a note about Olney's lesions, DXM doesn't cause them at any dose (in rats), I'm not sure about Ketamine or PCP. It would be kinda silly to compare the toxicity of PCP to the toxicity of crack and meth. They cause different kinds of brain damage and pose different physical threats. If you're going to compare the toxicity of PCP to another drug, compare it to another NMDA antagonist.-
Exposure to NMDA receptor antagonists may cause serious brain damage in the cingulate cortex and retrosplenial cortex regions of the brain, but evidence towards this hypothesis is not very strong at the moment. The experimental NMDA receptor antagonist MK-801 has been shown to cause neural vacuolization in test rodents that later develop into irreversible lesions called "Olney's Lesions."[19][20] Many drugs have been found that lessen the risk of neurotoxicity from NMDA receptor antagonists. Centrally acting alpha 2 agonists such as clonidine and guanfacine are thought to most specifically target the etiology of NMDA neurotoxicity. Other drugs acting on various neurotransmitter systems known to inhibit NMDA antagonist neurotoxicity include: anticholinergics, diazepam, barbiturates,[21] ethanol,[22] 5-HT2A serotonin agonists,[23] and muscimol.[24]