Many of the 4.1 million laptop batteries recalled by Dell on Monday will wind up in landfills around the world, but experts agree the environmental impact will be minimal.Lithium ion batteries are benign compared to the toxic ingredients in other rechargeable batteries with nickel-cadmium or small sealed lead-acid chemistries. Those heavy metals include cadmium, mercury and lead, elements that cause human and environmental health threats when they leach into groundwater or filter into the air after incineration, according to the U.S. Environmental Protection Agency.Recycling lithium ion batteries is easier to do. Dell is encouraging customers to return the potentially flammable batteries; the company will send a stamped envelope and address label to users who request a replacement battery.But many customers will never take either step\u2014claiming a new battery or returning the old one. Dell has not forecast the number of customers who will respond to the recall, but a spokeswoman suggested the 80\/20 rule would apply, with 80 percent of customers making the change."We certainly do not advise people to throw away the old batteries; we\u2019ve made it extremely easy to return them," said Anne Camden, a spokeswoman for Dell, of Round Rock, Texas.The number of people who return the batteries could be much lower."When you offer people a US$50 or $100 coupon in a mail-in rebate, you get about 50 percent compliance. When you offer them a $30 coupon, you get about 15 percent compliance. And that\u2019s when you\u2019re trying to give them cash," said Roger Kay, an analyst with Endpoint Technology Research Associates. "So if you\u2019re asking people to put a battery in an envelope, the likelihood is they probably won\u2019t do it."Even with curbside recycling programs, many homeowners don\u2019t bother to separate batteries from other trash, he said."Americans\u2019 attitudes about landfills are still pretty primitive. But Dell, like a lot of American companies, is pretty enlightened about how to handle toxic materials, so a lot of it will get recycled and purified and reused," he said.And compared to poisonous material like the arsenic derivative used in gallium arsenide microprocessors, the lithium in Dell\u2019s Sony-built batteries is nontoxic."Even if a customer places it in the trash can, and it enters the municipal solid waste stream, nothing\u2019s going to happen," said Norm England, president of the Rechargeable Battery Recycling Corp. (RBRC), which has processed faulty batteries from some of Dell\u2019s past recalls.RBRC is an arm of the Portable Rechargeable Battery Association (PRBA), a trade and lobbying group formed in 1991 by battery makers Energizer, Matsushita Battery Industrial of America (Panasonic), SAFT America, Sanyo Energy (U.S.A.) and Varta Batteries."Lithium ion batteries contain no scientifically proven toxic elements, and there are no existing laws or regulations requiring lithium ion batteries not to be placed in solid waste," England said.Environmental agencies in some states agree and do not define lithium ion batteries as toxic waste, but still recommend recycling oversight.RBRC collects batteries from many sources, amassing 2.4 million pounds of rechargeable batteries from its 35,000 public collection sites through the United States\u00a0and Canada during the first six months of 2006.Customers can find those sites at many retail stores, including Sony Style Stores, Circuit City, Rite Aid and Fry\u2019s Electronics. Customers can search for additional sites online\u00a0here and here.PRBA ships the batteries it collects to the International Metals Reclamation Co. (Inmetco) in Ellwood City, Pa., a division of Inco, one of the world\u2019s largest nickel producers. Inmetco passes the batteries to Falcon Bridge, a Canadian mining company whose workers recover the cobalt\u2014a valuable material that offsets recycling costs\u2014and recycle other materials like copper, gold and plastic.Environmental regulations outside the United States\u00a0and its trading partners can be much less stringent, but Dell bars its recycling contractors from sending electronic waste to countries with weak environmental laws."No environmental waste can be landfilled or exported to a developing nation," said Brian Hilton, a Dell spokesman.Dell has taken steps in the past to minimize the environmental impact of its products. Dell has offered free recycling since 2004 for customers who buy new Dell equipment. In June, the company expanded the program to include all Dell-branded PCs.And in July, Dell announced it would list 28 PCs and peripherals with the Electronics Products Environmental Assessment Tool, located at www.epeat.net. Government buyers use that site to ensure that the computers they buy have met the standards listed in IEEE 1680, a standard for environmentally sustainable electronics set by the Institute of Electrical and Electronics Engineers.-Ben Ames, IDG News Service (Boston Bureau)Related Links:\n\nDell to Recall 41.M Batteries Due to Fire Hazard\n\nSony Battery Issues Could Go Beyond Dell Laptops\n\nSony to Help Foot Bill for Dell Battery Recall\n\nDell Founder Tight-Lipped on Firm\u2019s TroublesCheck out our CIO News Alerts and Tech Informer pages for more updated news coverage.