“When’s the last time you watched TV by candlelight?” asks Arlene Blum, founder of the Green Science Policy Institute. Blum questions the logic of television sets being coated in chemicals that are either known health hazards or under-researched.

The voluntary standard governing the use of flame-retardant chemicals in electronics in the US, known as UL-94, is met by adding the chemicals not only to internal components but also to plastic outer casings, including those of TVs. Based on what’s called a “candle-flame standard,” it requires that items not ignite when they come into contact with a candle flame. Blum, a vocal opponent of flame-retardant chemicals in consumer products, thinks using flame retardants on the outer casings of electronics is unnecessary and puts consumers’ health at risk.

Consumers are often unaware of all the flame-retardant chemicals in and on electronics. While flaming laptops and even iPods – and recalls from manufacturers such as Dell, Apple, Lenovo, Toshiba and, more recently, Sony over fire safety fears – might help make the case for coating circuit boards with flame retardants, fierce debate is raging over whether they are necessary on the external plastic casings of items like televisions, stereos, computers, video game consoles and cellphones.

While public health advocates are fighting to reduce the use of flame retardants in electronics, flame retardant manufacturers routinely recommend international standards that would increase use of the chemicals across all types of electronic products.

One such standard was recently defeated by the International Electrotechnical Commission (IEC), an international industry standards group that sets voluntary standards for the electronics industry. But another is up for a vote this summer by both the IEC and the European standards commission (CENELEC). If it passes, Green Science Policy Institute research estimates it could increase the use of flame retardants in electronics by hundreds of thousands of tons. Companies are not required to disclose which chemical flame retardants they use, or how much, so it’s unclear how much is used in electronics today. But 816m pounds (roughly 370,000 metric tons) of the stuff is sold in the US annually, for use primarily in the construction, electronics, automotive and aerospace industries.

“We think coating plastic casings is a completely unnecessary use of these chemicals, and it’s one that directly impacts consumers,” says Simona Balan, who heads the electronics standards initiatives for the Green Science Policy Institute.

From 2002 to 2013, the flame retardants most commonly used in electronics, polybrominated diphenyl ethers (PBDEs), were banned or phased out in Europe and the US after researchers linked the compounds to neurotoxic effects and hormone disruption. Because electronics manufacturers do not disclose which flame retardants they use, scientists have only recently ferretted out the chemicals that have replaced PBDEs by analyzing currently available electronics.

Ana María Ballesteros-Gómez, an analytical environmental chemist at VU University Amsterdam, studied 13 products made since the phaseout and found one common flame-retardant chemical in all of them: a new, triazine-based brominated flame retardant that appears to have replaced polybrominated flame retardants. Although neither the US nor the European Union have declared this new compound toxic, researchers caution that it is very similar in structure to PBDEs and thus warrants further study. Blum has been pushing for regulation of the entire class of brominated flame retardants to avoid this sort of substitution of one, banned chemical, with another of similar structure that likely carries similar health risks.

Two of the more commonly used flame retardants – tetrabromobisphenol A (TBBPA) and tetrachlorobisphenol A (TCBPA), chemical cousins to bisphenol A (BPA) – are used internally on circuit boards and externally on plastic casings, and were recently deemed to be obesogens – which disrupt endocrines and promote obesity – by University of Houston researchers.

According to the study, about 150,000 tons of TBBPA and 10,000 tons of TCBPA are produced every year. Study author Maria Bondesson found that zebra fish exposed to doses of the chemicals for eight days developed more fat cells and were chubbier than those not exposed, despite a high-cholesterol diet for both groups. The dosed fish also remained fatter a month after exposure.

While the fish were exposed to higher doses than humans commonly would be, Bondesson, a research assistant professor of biology and biochemistry, said the size of the dosage was balanced out by the exposure time.

According to the Bromine Science and Environmental Forum, however, TBBPA have no health impacts on humans. Its fact sheet on the chemical states: “European Union studies twice have shown that exposure to TBBPA from consumer products is insignificant, or not detectable, depending on the application.”

Roughly a dozen flame-retardant chemicals are commonly used in electronics, according to the American Chemical Society. According to the North American Flame Retardant Alliance, part of the American Chemistry Council, all of them are safe.

“Consumers should know that flame retardants, like other chemicals, are subject to review by the Environmental Protection Agency and other regulatory bodies for safety,” the Alliance wrote in a recent statement about proposals to reduce the use of flame-retardant chemicals in various products.

“Flame retardants have been scientifically proven to help stop or slow the spread of fire, and they help save lives. NAFRA believes in strengthening fire safety and supports the use of flame retardants in those products where the chemistries can provide an important, added layer of protection.”

But while the chemicals are evaluated for safety, electronics manufacturers do not have to disclose which chemicals they use or how much of any one chemical, which public health advocates say makes it difficult to tell whether the chemicals are being used according to safety limits. Both the European Union and the US have regulations governing materials used in the components of electronics, but there’s currently very little regulation of any chemicals coating those components. Since the internal circuit boards of electronic devices pose a real fire danger, there’s little desire within the industry to reduce the amount used, even on external casings.

With little government or corporate incentive, Blum and Balan are focusing on two issues: defeating standards that would require the use of more flame-retardant chemicals, and raising consumer awareness – both of which are likely to be long battles.

“It took years to develop consumer awareness around flame retardants in furniture, and I don’t think most people know now that their TV cases contain flame retardants, too,” Blum says.