Seafood you buy at the grocery store has a thousand times that level of mercury.
Just because you can detect something at the PPB level doesn’t make it a hazard.
People tend to not truly grasp units that are in the extreme. They just see 60 and it seems like a fairly significant amount. The fact that the unit,PPB, is miniscule doesn’t always register.
And when did we start measuring things in parts per billion? IIRC, PPM was more common. I would imagine in any article trying to scare people into changing behavior that PPM just wouldn’t be the same as 1 PPM = 1000PPB.