Update, July 18, 2017:
More than 25 years after the state determined that 1,2,3-TCP causes cancer, the State Water Resources Control Board voted to approve a standard for the chemical in drinking water. They set the limit at 5 parts per trillion, a level supported by clean water and pesticide reform advocates. The state will now start water systems to test all of their wells every month starting in January.
Board chair Felicia Marcus called the vote, “a very important day for public health.”
“It’s a very serious public health threat,” agreed board Vice-Chair Steven Moore. “California officially determined that this is a carcinogen. And when you look at the science and the experiments and all that was done to show it, it is disquieting how serious and insidious this chemical is.”
Update, June 20, 2017:
The state water board has proposed a standard for 1,2,3-TCP and held a hearing to receive public comment. The state is proposing that the maximum contamination for 1,2,3-TCP in drinking water be set at 5 parts per trillion. The nonprofit Community Water Center, which advocates for safe, clean drinking water in the San Joaquin Valley, testified in support of the proposed standard.
State water officials have not yet formally implemented the standard, but they have issued an updated map showing contaminated wells.
The Fresno City Council has authorized a study to find out how to remove 12,3-TCP from the city’s water supply.
Update, January 2, 2017:
In January, The State Water Resources Control Board is expected to roll out the draft of a first-ever enforceable standard for 1,2,3-TCP in California drinking water.