RFID Chips and MRI

I was just curious if anyone had the answer to this. Hypothetically speaking, if the government was able to plant chips in people, through flu shots, etc.
1) Could they be made of all plastic and still work?
2) wouldn't they come out if someone had an MRI?

Thank you for your responses.

Titanium, Cobalt-Chromium, Copper, Stainless Steel and plastics are mri compatible.

Yep, I have titanium on board in the form of a 9 inch bar in my tibia and several other metal plates in my right leg and pelvis. I have been through many MRI's since and no problem at all with the Titanium Implants. I guess they are non-magnetic. I think non-ferrous (non-iron containing metals) are not magnetic, but could be wrong.

Don't be paranoid. They are not going sneak micro chip implants in vaccinations. Micro chips are the size of a grain of rice, and have you ever seen the size of a needle? Even if they did, there would be a huge pharmaceutical lawsuit, and people would stop taking vaccinations all together. I doubt that they could make micro chips mandatory in our life time. If they try, it would create a mass civil war.