Scientists at the Ecology Center bought the 36 most popular cell phones and smartphones dating back to 2007, and tested them for a variety of hazardous materials, such as lead, mercury, cadmium, heavy metals, and chlorine. The verdict? There wasn’t a single phone that was 100% free of hazardous materials, says Jeff Gearhart, research director at the Ecology Center. “These are very chemical-intensive products,” he says. “Overall, the industry seems to be improving,” he adds, but “there’s still a lot we need to do to reduce the overall lifecycle impacts.” More from Prevention: Do You Need A Media Diet?   Newer phones tended to fare better than older phones, they found, but two of the most popular phones on the market right now, Apple’s iPhone 5 and the Samsung Galaxy S III, were beaten by older models, despite the fact that both manufacturers have made pledges to phase out toxic chemicals, like chlorine. [sidebar] Here’s the final list of the top five (and the five worst) phones tested: Best:

  1. Motorola Citrus2. LG Remarq3. iPhone 4S4. Samsung Captivate5. iPhone 5 Worst:
  2. iPhone 22. Palm m1253. Motorola MOTO W233 Renew4. Nokia N955. Blackberry Storm 9530 For the complete ranking of all 36 phones, click here to read the full report online. Gearhart says that, most likely, you wouldn’t be exposed to any hazardous chemicals while using your phone. But where it really matters is with disposal. Americans toss 141 million cell phones and other mobile devices each year, just 8% of which get recycled. That means these chemical-filled gadgets either get sent to a landfill, where their components can leach chemical waste into groundwater, or they’re sent to incinerators, which burn them, releasing a whole variety of pollutants into the air that winds up in your lungs. So your best bet, regardless of which phone you have, is to ensure your old phone has as little a post-life impact as possible:

Replace, but only when needed. Sure, it’s tempting to buy the latest and greatest, but if your old phone still has a lot of life left, keep it around until it permanently bites the dust.Recycle it! Cell phone recycling programs are popping up all over the place. But not all are created equal: Some will disassemble your phone carefully and make sure hazardous materials are treated with care, while other programs ship phones abroad, where people working in unsafe conditions will take them apart. The Best Buy chain, which recycles cell phones, just announced that it’s partnering only with recyclers who’ve been certified to e-Stewards Standards, the most stringent international recycling standards out there. If you don’t have a Best Buy near you, you can find an e-Steward–certified recycler online.  

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