Parts Per Trillion

The unit of measure commonly used for dioxins and furans is "parts per trillion," or "ppt."

The action standard used by the U.S. government and many states is 1,000 ppt.

To put "parts per trillion" into perspective, one part per trillion can be considered equal to:

• One inch in 1.6 million miles
  
• One second in 32,000 years
  
• One cent in $10 billion
  
• One square foot of the state of Indiana