How much PFAS are we talking about here? What’s a “ppt”?

While PFAS are literally everywhere on the planet, there is not very much of them in most places.  We typically measure them in parts per trillion (a fraction with one on the top and a trillion on the bottom).  This range is so small that it’s really challenging to even think about.  Here are some of my favorite metaphors for ppt:

• One drop in twenty olympic sized swimming pools

• A day and a half in the 4.5 million age of the earth

• The weight of one person’s hand compared to the weight of every human being alive right now.

We are putting a million tons of PFAS into the environment each year. If that million tons spread out evenly over all the oceans on the planet (1,300,000,000 cubic kilometers or 350,000,000,000,000,000 gallons), that’s about a part per trillion. Yes, if we took all the PFAS we are emitting right now and polluted the entire ocean, we would be raising the concentration by about a ppt every year.

Whew. I need a nap after that one.