Will the Chinook salmon return?

Chinook Salmon migrate from ocean to freshwater streams.

After twenty years of research scientists in Washington state, San Francisco, and Los Angeles have solved the mystery of the Coho salmon die-off. The assassin, a chemical in tires.

The slayer, known as 6PPD, is a preservative used to stop tires from breaking down. Miniscule amounts break off as tires hit the pavement. When it rains the chemical, along with every other pollutant on the road, washes into storm…