By Katherine Hamilton

Alcoa shares were down Friday as investors worried about long-term disruptions in the Middle East, putting a damper on the alumina industry.

The stock fell 7.4% to $65.25 on Friday. Shares are still up 22% this year.

Alcoa, which produces aluminum, alumina and bauxite, on Thursday posted lower first-quarter sales and profit compared with last year. Executives told analysts the blockade in the Strait of Hormuz, an integral passage for alumina transport, resulted in a lower level of shipments in the quarter.

While Middle East customers are honoring their commitments by redirecting shipments elsewhere, investors are worried disruptions will continue, analysts say.

Alcoa reiterated its full-year outlook on Thursday, despite missing expectations for its first quarter. The company could still be facing long-term disruptions, however, as there is a risk of rising production costs, JPMorgan analysts said.

The analysts see risk from diesel, carbon-products and caustic-soda costs rising. Caustic soda accounts for about 15% of refining costs, and its cost has jumped 25% in the U.S. since the Iran conflict began, the analysts said.

If higher costs continue, the analysts believe cost pressure could show up in the fourth quarter because inventory takes five or six months to flow through.

President Trump said Friday that the U.S.'s naval blockade on Iranian ports will "remain in full force," a contrast from Iranian leadership's claims that the Strait was open.

Write to Katherine Hamilton at katherine.hamilton@wsj.com

(END) Dow Jones Newswires

April 17, 2026 12:56 ET (16:56 GMT)

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