antofagasta plc on wednesday downgraded 2022 production and cost guidance after an issue at its los pelambres project caused copper output to fall 65 in the second quarter the chilean copper miner cut fullyear production to 640000660000 metric tons down from its latest guidance of the bottom end of the 660000690000 tons rangerevised weeks after the issue at los pelambres was identified on may 31 antofagasta detected a leak in the underground pipeline that transports concentrate from its los pelambres concentrator plant to the port in addition the company on wednesday raised 2022 net cash cost guidance to 165 a pound from 155 reflecting inflation in diesel and other input prices for the second quarter the group reported copper production of 129800 tons down from 138800 tons in the first quarter net cash costs a pound jumped to 190 from 175 in the period