When the Food and Drug Administration unveiled proposed regulations for electronic cigarettes back in April, it was an announcement five years in the making. Now several months later little has happened, and a group of senators fear that the failure to quickly finalize the rules has led to the perpetration of misleading health warnings created by tobacco companies themselves.

In the letter sent to the FDA on Thursday senators Barbara Boxer of California, Dick Durbin of Illinois, Richard Blumenthal of Connecticut, Jack Reed of Rhode Island, Sherrod Brown of Ohio and Edward Markey of Massachusetts urged the agency to adopt stronger warning labels for e-cigarettes and to quickly finalize proposed regulations.

The group expressed their concern that the proposed warning label does not adequately communicate the health consequences of e-cigarette use based on scientific facts.

“We further urge the FDA to adopt aggressive warning labels that correctly communicate the health consequences of e-cigarette use and to take this opportunity to review and update warning labels for all tobacco products, including those that have long been on the market, to ensure that consumers are aware of their risks,” the senators write.

Under the proposed rules, the warning label on the electronic products must read: “WARNING: This product contains nicotine derived from tobacco. Nicotine is an addictive chemical.”

In addition to asking for a more defined warning label, the senators pushed for the FDA to quickly finalize regulations for fear that in the absence of clear federal standards, e-cigarette manufacturers are beginning to concoct their own health warnings about their products.

The group referenced the inconsistency between warning labels from well-known cigarette manufacturers Reynolds American and Altria.

The Reynolds label states that their product is not intended for those “who have an unstable heart condition, high blood pressure, or diabetes; or persons who are at risk for heart disease or are taking medicine for depression or asthma.” On the other hand the Altria label states, “Nicotine is addictive and habit forming, and is very toxic by inhalation, in contact with the skin, or if swallowed.”

“These two examples show the lack of uniformity of information across companies and highlight how voluntary health warnings often leave out known dangers from nicotine use – such as risks to adolescent brain development and pregnant women, as well as the dangers posed by additives and other chemicals that may be in e-cigarettes, such as benzene and formaldehyde,” the senators’ letter reads.

Thursday’s letter marks the second time the group of senators has appealed to the FDA to finalize rules.

In late April, the FDA announced it was ready to begin regulating e-cigarettes and unveiled plans to finalize the regulations within one year.

The proposed regulations, which would also impose restrictions on nicotine gels and pipe tobacco, require manufacturers to register their products with the FDA within two years. In the meantime, companies could continue to sell new and existing devices without FDA approval.

However, before the regulations can become legal they must go through a public comment process and prevail over potential legal challenges before coming into effect.

It’s that process the senators say is taking too long and could be hurting the eventual effectiveness of any kind of regulation.

The FDA previously came under fire from consumer advocates and political figures for its slow progress in regulating the e-cigarette industry. Back in early April, senators at a Congressional budget hearing told FDA Commissioner Hamburg that the agency’s failure to issue regulations was unacceptable.

In 2009, the FDA sought to impose restrictions on the devices, which it described at the time to be medical devices designed to deliver nicotine, but a federal court struck down that attempt. The following year, the agency declared it had the power to regulate the devices under its authority to regulate tobacco products.

E-cigarettes, and their potential health risks, have been at the center of heated debate between supports and opponents of the devices.

Companies who manufacture the devices believe they should be exempt from FDA regulations, contending it would stifle innovation, damage small business and hurt consumers trying to quit smoking.

Still, there is no clear data on the health impact associated with the devices. Supporters contend that the devices help consumers stop smoking traditional cigarettes, while opponents argue the devices are attractive to teenagers and secondary risks, such as poisoning and a tendency for the devices to explode, could be more deadly than traditional cigarettes.

Earlier this year, the New York Times explored one of the deadliest attributes of e-cigarettes: liquid nicotine. When ingested or absorbed even small amounts of the toxin could prove deadly.

The Centers for Disease Control and Prevention released a new report [PDF] in April that showed the number of calls to poison centers involving e-cigarette liquid containing nicotine rose from one per month in September 2010 to 215 per month in February 2014.

The popularity of e-cigarettes grown immensely in recent years, with sales of the devices reached more than $1.5 billion in 2012.

But even as more consumers use the devices, some cities have banned the products from being used in public places, such as parks or on the subway.

Senators call on FDA to protect consumers by adopting stronger warning labels for e-cigarettes [Senator Barbara Boxer]

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