Higher Plastics Costs Are Becoming the Next Inflation Headache

US plastic suppliers say they are running out of room to absorb high costs of raw materials, raising the prospect of price increases for consumer goods ranging from groceries to cars later this year.

A gauge of wholesale prices of plastic resins and materials jumped by 14% to an almost four-year high last month as the Iran war choked off supplies of key components. For producers like Shawn Gross, whose Corry, Pennsylvania-based company supplies molded parts used in automotive and heating systems, the squeeze is reaching a breaking point.

“We are going to need to pursue the price increases with ...