shares have declined 13 since the investigation published july 9 revealed how telecom companies like att have left behind more than 2000 old leadencased cables across the us shares of att t 669decrease red down pointing triangle dropped to their lowest closing price in three decades extending recent losses following a wall street journal investigation into toxic lead cables left behind by telecommunications companies att’s stock fell 67 on monday to 1353 a share its lowest close since february 1993 shares have declined 13 since the investigation published july 9 revealed how telecom companies like att have left behind more than 2000 old leadencased cables across the us relics of the old bell system’s regional telephone network journal testing found numerous cables leaching lead into soil and water at levels exceeding regulatory safety guidelines wall street analysts have since raised questions about liabilities related to the cables and the potential impact on companies’ bottom lines some firms have downgraded their ratings on some telecom stocks “it’s really the fear of the unknown” said frank louthan iv a managing director and telecommunicationsservices analyst at raymond james “it’s very difficult to quantify how much of this network is out there it’s difficult to quantify the cost it’s difficult to quantify the liability” shares of verizon communications vz 750decrease red down pointing triangle pulled back 75 on monday their worst oneday performance since october 2008 and closed at their lowest level since september 2010 verizon was the worstperforming stock in the dow jones industrial average frontier communications parent fybr 1579decrease red down pointing triangle  which owns networks acquired from legacy bell companies dropped 16 lumen technologies lumn 811decrease red down pointing triangle  another telecom company with bell assets shed 81 att verizon frontier and lumen together have lost about 36 billion in market value since the publication of the wsj investigation according to dow jones market data att didn’t immediately respond to requests for comment about the share slide a verizon spokesman said in an email the company has been modernizing its network for two decades and only a small percentage of the existing network currently includes leadsheathed cable verizon has started its own testing of several sites and is “taking these concerns regarding leadsheathed cables very seriously” he said “we have not seen nor have regulators identified evidence that legacy leadsheathed telecom cables are a leading cause of lead exposure or the cause of a public health issue” a ustelecom spokesperson said in a statement “many considerations go into determining whether legacy leadsheathed telecom cables should be removed or should be left in place” wall street downgrades in the sector continued monday as analysts at citigroup on monday reduced their ratings on att frontier and telephone and data systems to “neutralhigh risk” while remaining “neutral” on verizon “the industry’s historical use of lead sheathed cabling is likely to remain an overhang for the stocks and valuation for at least a few months and potentially longer until the market can better measure the financial risk” citigroup analyst michael rollins wrote in a report new street research last week estimated removing all leadcased copper wires across the country could cost as much as 59 billion raymond james’s louthan said he believes the costs for removing lead cables are lower than some other projections on wall street he estimates the cost per mile of cable would be around 4000 factoring in environmental remediation the telecom companies are set to report quarterly results in the coming weeks with analysts and investors expecting to hear from corporate management in the aftermath of the journal investigation verizon and att are due to report earnings next week while lumen and frontier are slated for the week following “the carriers have not made much of a statement unfortunately hopefully they will correct this on their earnings calls next week and be able to get investors some color on what the exposure is from a network perspective” louthan said