Can laser tattoo removal cause heavy metal poisoning? I am removing a black tattoo with PicoSure.

Today, as I was getting my ink zapped away, my mouth was filled with a strong metallic taste (vaporized ink?). This got me wondering what was in the ink, where in my body the broken up pigment is going (are the particles going to be lodged in my lymph nodes forever-- can I get an MRI?), and whether I am putting myself at risk of exposure to neurotoxic metals by removing my tattoo. If I am concerned about neurotoxicity, should I stop my treatments?