BP Plc said it has been made aware of potential contamination problems with some shipments of oil from Azerbaijan, Bloomberg reports.

The company said the issues relate to organic chlorides, a chemical that can damage refineries and equipment if present in significant quantities.

Italy’s Eni SpA later said that it purchased some of the contaminated cargoes and some have entered its refining system.

Large amounts of Azerbaijani crude oils are transported by pipeline to the port of Ceyhan on Turkey’s Mediterranean coast. BP operates BTC Co., which built the pipeline.

“BTC Co has been made aware of a potential quality issue related to organic chlorides in some BTC blend loadings. BTC Co is currently assessing the quality of the crude oil across all the facilities along the pipeline,” the company said in a statement.