Fear of fires, especially from lit cigarettes, helped ignite the decades-long practice of adding fire retardant chemicals to furniture and other household items. But evidence that some of the chemicals could cause cancer or other health problems eventually led to a protracted fight to get them out of furniture. Now couches made in 2014 could hit the market flame retardant–free. Their chemical cousins, however, are still routinely doused on today’s electronics.

A smorgasbord of synthetic chemical retardants came of age in the era of boxy cathode-ray tube television and their bulky, flammable casings. Although electronics are now much smaller and thinner, flame retardants are still infused into or onto electronic circuit boards and casings. Less plastic casing means less fuel for a fire, but the use of highly flammable lithium ion batteries represents other risks, contend flame retardant proponents. And yet in recent years it’s become apparent that flame retardants used on furniture provide no meaningful protection. Is the story the same for our televisions, cell phones and laptops? The replies from experts continue to be divisive.

The chemicals coating our electronics sometimes come with a disturbing profile. One common flame retardant used in the plastic casings of electronics, decabromodiphenyl ether, was voluntarily phased out by industry at the end of 2013 due to health and environmental concerns, including that it could potentially cause cancer or impact brain function. But some of the many alternatives that the U.S. Environmental Protection Agency anticipates will be used could degrade into tetrabromobisphenol A—itself a flame retardant that was labeled as a carcinogen by the National Institute of Environmental Health Sciences last year.

Such chemicals are attractive because they are effective and cheap. Tapping more inherently fire resistant metals like titanium or steel for enclosures comes with a higher price tag, and companies may fear such products would be less attractive to users. Flame retardants have different chemical compositions and work in varying ways to slow a burn: some react to displace oxygen needed for a fire; others bind with molecules that would help feed the flames; others form a protective sheath on the surface of material that would otherwise be flammable.

Flame retardants are chemically bound to the circuit boards of personal electronics during production—helping to keep any chemicals from seeping into the environment or possibly causing health repercussions for consumers (although it’s a different story for workers who process discarded electronics). The function of circuit boards is to transmit electrical current, so flame retardant proponents say fire protection is an obvious necessity.

Flame retardants are also embedded in the plastic shells that encase circuitry and electronics, with potentially more alarming health impacts. They are added to the plastics during a late stage of manufacturing without bonding to or reacting with the product material, making it easier for them to leach into the environment.

In general, industry is responsible for regulating its own acceptable fire risk in electronics. In the U.S. the electronics industry abides by voluntary consensus standards for keeping electronics from bursting into flames but there is no specification about what compounds must be used nor any limit (other than economics) on maximum use. Thanks to the Consumer Product Safety Act, the federal Consumer Product Safety Commission says it has the ability to enforce action on risky products if it hears about it. Indeed, the industry as a whole, or perhaps a company’s competitors, have an incentive to report unsafe products given that fires fueled by laptops or phones make for bad press, but this system is still self-policing.

It is difficult for outside groups to gain insight into risk because companies typically do not share information on which flame retardants they use. “No manufacturer will tip their hands on what are in their products more than they have to,” for fear of competitors undercutting or reverse-engineering products, says Alexander Morgan, a fire scientist at the University of Dayton Research Institute and a member of the American Chemical Society . Even companies that say they are using one flame retardant may, even unbeknownst to them, be using small quantities of others if international subcontractors adulterate the products, he says.

So are consumers being exposed to a smattering of flame retardants every time they whip out their phones or plop down in front of the television? The jury is still out. To date there is very little data on chemical leaching from these products. Some companies have preemptively turned to alternatives. Apple says it phased out all of its brominated flame retardants (BFRs) in 2008 (some of which are linked with maladies including cancer and adverse effects on fetal and child development); so newer iPads, iPods and iPhones should be free of such chemicals—but not all companies have followed suit. Apple says it instead uses a mix of more inherently fire resistant materials or safer flame-retarding alternative chemicals. Motorola says its products are BFR-free, too, and Sony says it has phased BFRs out of select products released after July 2013. Still, five other companies did not respond to requests for information from Scientific American by press time.

There is no easy way for consumers to find out which products are free of flame retardant or to track the amount of retardants poured into or coating their electronics. EPA, for one, does not monitor the amount of flame retardants used in electronics.

Moreover, the extent to which flame retardants are truly necessary to safeguard electronics is unclear. It’s difficult to discern who is right, especially when the stakes of being wrong could lead to serious consequences. “Maybe people don’t realize how flammable modern plastics are—even more than wood,” Morgan says.

Yet “there has never been any valid statistical demonstration that flame retardant chemicals of the types and concentrations used in consumer products have resulted in death or injury reduction,” says Vytenis Babrauskas, the fire scientist whose work was distorted and cited for years as the grounds for flame retardant use in furniture.

The Bromine Science and Environment Forum, a Brussels-based industry group, maintains that flame retardants in consumer products can save lives by preventing fires from starting or spreading. The argument is playing out in peer-reviewed literature as each study prompts fresh criticism. Arlene Blum, a longtime advocate on limiting flame retardant exposures and a visiting scholar in chemistry at the University of California, Berkeley, says there is no reason to use them in electronics casings.*

For now the issue remains one in which the cure may be as hazardous as the illness it supposedly fights. “Ultimately,” Morgan says, “everyone has to live with some margin of risk.”

*Clarification (1/28/14): This sentence was edited after posting to clarify Blum's statement.