Formaldehyde in vaccines

[cartersmom]

The formaldehyde in vaccines is a synthetic version of the type that is naturally produced in our bodies and not the type that is in embalming fluid and building materials correct?? How do we know this synthetic version is not harmful??

[Spy]

We don't. :D We just can't claim that it is harmful based on it being the same thing as embalming fluid which it is not exactly.