Upon random web surfing, I noted several animals which were made permanently green and photoluminescent by being injected with something while they were still in the womb.

Was this actual GFP, or was it some DNA coding which produced the GFP? Would green pigs produce green ham?

Is GFP toxic to humans? If not, would it be practical for novelty usage, such as being used to color the ocular tissue or epidermis?

Actually what you saw was AGS artificial genetic splicing. Where hyperluminscent genes were used as a gene therapy in prenatal pigs as a test for other prenatal gene therapies. The gene was obtained from a deep water specimen that could glow naturally or produce light. Its not toxic to humans and is now part of the pig's genome and will be passed down.