Experts have been claiming that mobile phones carry with them health-risk chemicals but a new study now indicates that the hazardous materials inside the ubiquitous devices have whittled down considerably.
A joint report by teardown site iFixit and the U.S.-based Ecology Centre showed that handset manufacturers have increased their efforts to reduce the toxin contents of smartphones, which were manufactured and shipped to markets worldwide in hundreds of millions annually.
The recent study, according to Ecology Centre research chief Jeff Gearhart, had analysed 36 popular handsets from various brands - all of them, researchers said, "contained at least one of the following hazardous chemicals: lead, bromine, chlorine, mercury and cadmium."
Flame retardants, PVC and tin are also present on the main communication tools that consumers use, iFixit said on the report, which was published in HealthyStuff.org.
These mobile phones were mostly introduced to global markets in the past five years, Mr Gearhart pointed out, and the study has established that the most recent the handsets were made the less harmful they became.
Emerging as the greenest of them all is the Motorola Citrus, which the American phone maker had issued in October 2010, researchers said.
Adjudged as the most risky handset still in circulation is the iPhone 2G, which was initially rolled out by Apple in 2007, though production of which has since been discontinued, the report said.
The tech giant, however, has two mobile phones in the Top 5, iFixit said, and they are the blockbuster iPhone 4S and the iPhone 5, which started hitting the international market in late September and should attain a global presence in the few months ahead.
Rounding up the elite list are the LG Remarq and Samsung Captivate, the report said.
"Mobile phones are chemically intensive, and full of chemical hazards, but they've been getting a lot better," Mr Gearhart told Agence France Presse (AFP) on Thursday.
He lauded, at the same time, better regulatory precepts that were introduced in Asia and Europe over the last few years, plus the emerging trend in which "consumer interest in healthier products is driving companies to design and produce healthier products."
In a blog he wrote supplementing the new report, iFixit chief executive Kyle Wiens has confirmed that "there is a trend of less toxic (deployed with mobile phones) over time ... but it's not good enough."
The report underscored that once the process of manufacturing mobile phones has commenced, the danger of heavy metals mixing into groundwater and air also started.
"These (chemicals) are not (the things) we want in our water or air,' Mr Wiens said, adding that it's only appropriate for gadget vendors to further improve on their manufacturing and release the most environment-friendly product.
On the part of consumers, iFixit said they would help create a cleaner environment by rationalising their purchase of consumer electronic products - the more time they hold on to a gadget, the better, Mr Wiens said.
And when the need arises to dispose that outdated or non-functioning gizmo, it is best to recycle, the iFixit chief stressed.