"We did move a couple of supply chains around to make sure we were protected." he said on "Squawk on the Street.
"If we add everything up from the quarter, [tariffs] affected about $50 million of our business," he estimated, which "in the scheme of our numbers is nothing." Prices were raised a bit to cover it, he added.
On Thursday morning, DowDuPont announced better-than-expected third-quarter adjusted earnings of 74 cents per share. Revenue of $20.1 billion was slightly below estimates. The company also unveiled a new $3 billion stock buyback program.
Shares of DowDuPont were up about 6 percent by midday. But they're still down about 20 percent year to date.
"With the stock trading where it's at, we wanted to get going on the share repurchase," Breen said. "We were waiting to get our capital structures done for the three companies."
He predicts the stock will rebound over the next five months when the buyback program gets underway and DowDuPont makes its first company split.
Michigan-based DowDuPont plans to break up into three companies in 2019. The materials science unit is expected to go first in the first quarter, followed by the agriculture and specialty products units.
After the spinoff, Breen will become executive chairman of specialty products. The current COO of the unit, Marc Doyle, will become its chief executive officer.
Last year's $130 billion merger of Dow Chemical and DuPont created the world's largest chemical maker.