Hard PFAS Quiz

Incorrect.

PFAS levels have decreased in the general population since the 2000s. This is partly because of the phase-out of PFAS. More and more actions to decrease the general population’s exposure to PFAS have led to these results, too!

Incorrect.

It’s six: PFOA, PFOS, PFHxS, GenX, PFNA, and PFBS.

Incorrect.

This one’s complicated, but this is false.

There’s very strong evidence that certain types of PFAS compounds, like PFOA and PFOS, can cause cancer. However, for the vast majority of other PFAS compounds, scientists have not yet evaluated whether they can lead to cancer. Because many PFAS are chemically similar to PFOS and PFOA, scientists suspect that other PFAS may have similar health effects.

Incorrect.

A maximum contaminant level, or MCL, is an enforceable water standard. A health advisory level, or HAL, is not technically a standard. It's an non-enforceable level recommended by the Environmental Protection Agency or others. In March 2023, EPA proposed a PFAS MCL, which are expected to come into effect by the end of 2023.

Incorrect.

One debate in the PFAS world is whether certain pharmaceuticals should be considered PFAS or not. Certain medicinal compounds have similar carbon-fluorine parts that do not break down easily.

All definitions of PFAS include PFOA and PFOS. The other two answers are incorrect.

Incorrect.

It’s false.

PFNA, PFHxS, and GenX each have a standard of 10 parts per trillion. The group limit for PFNA, PFHxS, PFBS, and GenX combined is a unitless measure known as a hazard index. The hazard index is a relatively novel approach to address PFAS as a mixture of co-occurring chemicals.

Incorrect.

PFOA and PFOS are the two most common PFAS in drinking water and people’s blood. Although major U.S. manufacturers have agreed to phase out PFOA and PFOS in consumer products, other countries still produce them, and many companies have been replacing them with other PFAS, such as GenX, that raise similar health concerns.

Incorrect.

EPA’s CompTox database currently identifies over 12,000 compounds as PFAS. You can sometimes see the count as “>4700” or “>9000.”