Verizon Communications Inc (VZ  ) announced launching an investigation to clarify the extent of potential lead contamination probably linked to its aging phone cables.

The telecom operator is testing various sites where lead was reported to be leaching into the ground from wiring dating back to the early 20th century, as per Bloomberg.

Notably, according to a recent report by the Wall Street Journal, several prominent telecommunications companies possess underground cable networks that contain hazardous lead substances. Over time, as the lead deteriorates, it presents a significant environmental risk.

The report noted Verizon saying that lead in the environment may come from various industrial uses other than telecom.

The old landline networks were built during the late 1800s, with lead starting to be phaseout in the 1950s, and most of the legacy networks were owned by several national carriers, including AT&T Inc (T  ).

As per the report, the lead issue-related uncertainty can push the cleanup costs, leading to a further difficult year for telecom operators.

Price Action: VZ shares are trading higher by 1.49% at $31.93 premarket on the last check Tuesday.