PITTSBURGH — Moody’s Investors Service has lowered the bond rating of the Pittsburgh-based West Penn Allegheny Health System even further into junk bond status because the hospital network may file for bankruptcy protection.

Highmark has proposed a $475 million takeover, but wants West Penn to file Chapter 11 as part of that process in hopes of trimming the network’s debt. West Penn has $750 million in bond debt and $280 million in unfunded pension liabilities.

Moody’s knocked the rating down from ‘Caa’ to ‘Ca’ on Tuesday, its next-to-lowest bond rating. West Penn has the lowest rating of more than 400 health agencies rated by Moody’s.

West Penn tried to nix the Highmark deal over the insistence that it file for bankruptcy, but a county judge wouldn’t let West Penn walk away.

Vehicles recalled for steering defectsTOKYO — Toyota says it’s recalling 2.77 million vehicles around the world for a steering shaft defect that may result in faulty steering and a water pump problem.Japan’s top automaker said no accidents have been reported related to these two problems announced today.Some 1.51 million vehicles are being recalled for the steering defect in Japan and 1.25 million vehicles abroad, including 670,000 in the U.S.Affected models include the Prius hybrid, Corolla, Wish and other models produced in Japan from 2000 to last year, and from 2000 to 2009 overseas.Toyota is also recalling 630,000 vehicles spanning five hybrid models, including the Prius, for a defective water pump.

Environmentalists to appeal drilling rulingERIE — The Sierra Club and the Allegheny Defense Project have filed notice that they’re appealing a federal judge’s September ruling that says the U.S. Forest Service can’t regulate gas or oil drilling or other efforts to access mineral rights in the Allegheny National Forest.U.S. District Judge Sean McLaughlin’s upheld an earlier decision that lifted a de facto ban on drilling in the northwestern Pennsylvania forest.The judge found that the Forest Service had no more right than any other surface land owner to deny access to underground mineral rights owned by others.The Forest Service owns the surface of the 513,000-acre forest, but only 7 percent of the mineral rights.

Home Depot 3Q results edge upNEW YORK — Home Depot’s net income rose slightly in the third-quarter, as glimmers of a housing market recovery and storm-preparation added to sales and offset costs related to closing stores in China.Results beat expectations and the company also raised its forecast for the year. Shares rose nearly 4 percent.Home improvement companies have long been under pressure due to the weak housing market, as consumers cut back on large-scale renovation projects. But they stand ready to benefit as evidence mounts that the housing market is slowly improving.