Is There a Difference Between Aluminum That Is Injected vs. Ingested?

Paul A. Offit, MD, explains the difference between aluminum injected in a vaccine and aluminum ingested through food and water.


Is there a difference between aluminum that is injected vs. ingested?

Paul Offit, MD: Hi, my name’s Paul Offit. I’m talking to you today from the Vaccine Education Center here at The Children’s Hospital of Philadelphia. There’s a question that comes up about one of the adjuvants that’s used in vaccines, which is called aluminum. There are aluminum salts that are used as adjuvants.

What adjuvants do is they lessen the number of shots that you need to get, or lessen the amount of the active ingredient in a vaccine that you need to get, or both. And, you know, people wonder whether aluminum, which is an abundant light metal, can do harm. Well certainly we’re exposed to large quantities of aluminum in the food that we eat or in the water, or anything made from water, that we drink. But people could reasonably ask, “Isn’t there a difference then between when you inject somebody with aluminum versus when you ingest aluminum, or eat it?” And the answer is yes.

It’s actually, you’re much more likely to have aluminum in your circulation if you inject it than if you ingest it. But the point is that there’s so much more aluminum in the environment, either in the food you eat or the water you drink, than you would ever get as a shot in vaccines. That even though there is that difference between injection and ingestion, there’s logarithmically so much more aluminum that you ingest that you actually have far more aluminum in your circulation because of what you eat and drink than you would ever get from vaccines.

Then again, usually when people have problems with aluminum, it’s because they have kidneys that don’t work well or don’t work at all. And, or are getting large quantities of antacids, which contain a lot of aluminum. Or they’re getting intravenous fluids that contain aluminum.

So it’s really not an issue and hasn’t been. I mean, a number of groups have looked at the data on aluminum as to whether or not it’s harmful. And we’ve been using aluminum in vaccines now for 70 years. And the answer is no, aluminum salts contained in vaccines are safe.


Related Centers and Programs: Vaccine Education Center

Last Reviewed on Aug 11, 2015