Understanding ppm vs. ppb vs. percent — what do the terms “parts per million,” and “parts per billion” mean?
2021 | Background Science | Background Science for Lead | Keystone Article | Math Class | Science Class
For those new to this website: Tamara Rubin is a multiple-federal-award-winning independent advocate for childhood Lead poisoning prevention and consumer goods safety, and a documentary filmmaker. She is also a mother of Lead-poisoned children (two of her sons were acutely Lead-poisoned in 2005). Since 2009, Tamara has been using XRF technology (a scientific method used…