Most of us have heard of cyber crime, such as stealing identities, reading private information from your computer’s hard drive and using your credit card numbers. And many of us have heard of the problem of electronic waste that we think is being recycled properly ending up in toxic dumping grounds in third-world countries like Ghana.

But cyber crime from e-waste? It happens when computers donated for recycling or reuse make it to places like Ghana, which the State Department lists as one of the top sources of cyber crime in the world.

A PBS Frontline episode chronicles the problem, showing not only how children in poverty-stricken towns dangerously burn plastic computers and TV casings to retrieve and sell metals inside, but how your personal data may also be at risk.

Before computers and other electronics make it to the toxic dumping grounds, they are sorted to determine which pieces can be resold. And guess what happens to your computer hard drives, even if you think you have deleted your data? “I can get your bank numbers and retrieve all your money from your accounts,” says a Ghanaian computer scientist Enoch Kwesi. “It happens through a backup on your hard drive.” In other words, the data still exists, even if you thought you deleted it.

And everyone, including large government intelligence agencies, is susceptible. A team of university researchers purchased hard drives in Ghana that still contained sensitive files from United States intelligence agencies, NASA, the Transportation Security Administration, and military contractor Northrup Grumman. Can you say national security breach?

So how can you be sure to properly “wipe” a hard drive of all the data? Here are some Dos and Don’ts:

• Don’t just delete files. You’re only deleting the location, not the data.
• Don’t just reformat the disc. Reformatting is better than deleting, but some data remains and can be reassembled.
• Don’t use a magnet. Some recommend this to magnetize the drive, but some data may still be available. And how do you really know it worked?
• Do use a good data-wiping program. Some are free and available over the Internet. There’s a CNET video on the DBAN (Darik’s Boot and Nuke) software, and a good guide to properly wiping your hard drive of data can be found here.

But the best way to be sure data can’t be retrieved from a hard drive? Literally smash it to pieces, an expert on the Frontline episode demonstrates, so it can no longer spin. Then bring it to a responsible recycler, preferably one that belongs to e-Stewards or has taken the Basel Action Network pledge.

Steven Castle - Contributing Writer

Steven Castle is Electronic House's managing editor. he has been writing about consumer electronics, homes and energy efficiency topics for two decades. He is also the co-founder of GreenTech Advocates.