Preventing little Susie and Jamal—as well as Fido and Fluffy-from drinking sweet—tasting but toxic antifreeze seems like a cause that would be without opponents. Antifreeze containing ethylene glycol is linked to thousands of child poisonings and tens of thousands of pet deaths in the U.S. each year. Because of this, Congress could require manufacturers of antifreeze sold to consumers to add a bitter chemical to this automotive fluid. Proponents of such a law, who include Republicans and Democrats, say this will prevent children and animals from drinking antifreeze.
But some Democrats, while heartily endorsing the protection of youngsters and pets, oppose antifreeze-bittering bills pending before the House and Senate. They cite concerns over whether the bittering agent specified in the legislation will deter animals from swallowing antifreeze. They also wonder whether wide use of the bitterant in antifreeze could render drinking-water supplies unpalatable. And some are attacking the bills' liability protections.
The measures specify that manufacturers be required to add a single chemical, denatonium benzoate (DB), as a bittering agent to ethylene glycol-based antifreeze sold in retail establishments to consumers. DB is a powerful bittering agent that has been used in consumer goods for more than 40 years. The legislation would also provide a liability shield for companies that add DB to their antifreeze.
Following a subcommittee hearing on May 23, the House Energy & Commerce Committee on July 12 approved its version (H.R. 2567) of the antifreeze-bittering bill. The Senate Environment & Public Works Committee adopted similar legislation (S. 1110) in March. The measures are pending on the Senate and House floors, and Congress could pass final legislation before the end of 2006.
Ethylene glycol-based antifreeze, the type most widely sold in the U.S., is toxic to the kidneys of humans and other animals. According to the Doris Day Animal League, which has spearheaded the push for bittering legislation, a teaspoonful of this type of antifreeze can kill a cat, and 1-2 tablespoons can kill a 100-lb dog.
Concerns about adding DB to antifreeze aren't about the bittering agent's potential toxicity-people and animals are unlikely to ingest enough DB to make them sick. And cost isn't a big issue. The Consumer Specialty Products Association (CSPA), which represents antifreeze manufacturers, estimates that adding an appropriate amount of DB to make the automotive fluid bitter carries a price tag of 3-4 cents per gal.
Very low concentrations of DB taste horribly bitter to most humans, making it highly effective in deterring people of all ages from drinking common household chemicals, such as nail polish remover. But tests on whether DB will deter dogs and cats from lapping up antifreeze have given mixed results.
Mandating the addition of DB in the absence of solid data on whether it discourages animals from consuming antifreeze will give pet owners a false sense of security, Rep. Hilda L. Solis (D-Calif.) said at the July 12 hearing. Sara Amundson, legislative director for the Doris Day Animal League, told C&EN, "We are abiding by the precautionary principle," referring to the concept that governments should act on the basis of credible but incomplete information. Given that some evidence suggests DB is effective on animals, addition of the substance to antifreeze may prevent many animal deaths at a very low cost, she said. This is in addition to halting accidental ingestion of antifreeze by children and use of the substance in suicides and murders, Amundson said.
CSPA wants a national standard on bittering agents. Three states—California, New Mexico, and Oregon—already have laws requiring the addition of bittering agents to antifreeze, and other states are considering similar bills. The pending legislation would preempt any state law requiring a bitterant in ethylene glycol antifreeze.
"We simply can't have a patchwork of laws," said Phil Klein, CSPA senior vice president for legislative and public affairs. The trade group represents the five major antifreeze manufacturers in the U.S.: Honeywell, Old World Industries, Shell, ChevronTexaco, and Valvoline. Together, they have annual retail sales of 150 million to 200 million units, which are mainly 1-gal containers of antifreeze, Klein told C&EN.
Federal preemption of state action on bittering agents in antifreeze has gained the proposed legislation some opponents. Rep. John D. Dingell (D-Mich.), ranking minority member of the House Energy & Commerce Committee, said that with this provision, "no state will be able to use a more effective or environmentally safer bittering agent in the future." Dingell, like a number of other Democrats in the House and Senate, said many questions remain unanswered about the environmental impact of DB.
The American Water Works Association, whose member utilities supply more than 80% of U.S. drinking water, worries that if widely used in antifreeze, DB will end up fouling wells.
Speaking on behalf of the utility group, Tom Bonacquisti of the Fairfax County Water Authority, in Virginia, told the House subcommittee in May that the denatonium ion, which is responsible for the bitter taste of DB, is not easily biodegradable.
"We believe it is reasonable to expect contamination problems as DB accumulates in the groundwater supplies," Bonacquisiti said. "Given the extreme bitter properties of DB, it appears that tiny amounts of the chemical could render drinking-water supplies bitter and unpalatable."
The Environmental Protection Agency has limited information about DB and has performed only some screening-level analyses of this compound, according to Jim Willis, director of EPA's Chemical Control Division. On the basis of its structure, the substance is predicted to be water soluble and resistant to biodegradation, he told the House Energy & Commerce Subcommittee on Environment & Hazardous Materials. DB released into a sewer system would likely adsorb onto sludge and get removed before treated wastewater is released to rivers, lakes, or streams, Willis said. DB released to surface waters is expected to accumulate in sediments, he added.
"The chemical would not be predicted to readily migrate to groundwater because of its propensity to adsorb to soil," Willis said. "However, with sandy soils, potential movement to groundwater would be greater."
Amundson of the Doris Day Animal League told C&EN no drinking-water problems have been seen from DB in California, New Mexico, and Oregon, the three states that already require the bittering agent in antifreeze. Plus, DB has been used in other consumer products for more than 40 years without any reports of it fouling water supplies, she added.
Both the Senate and House bills would require the Consumer Product Safety Commission to conduct an environmental impact evaluation of DB before requiring addition of the substance to antifreeze.
Some critics challenge the legislation's mandate for the use of a particular chemical as a bittering agent. Patrice L. Simms, senior project attorney for the Natural Resources Defense Council, told the House subcommittee that the bill should "simply require the use of an effective bitterant." Simms explained, "Allowing flexibility in the use of bitterants would make it easier for industry to respond to any problems that might arise with a particular chemical or to shift to a more effective, more readily available, safer, less expensive, or otherwise more appropriate chemical if one were to emerge."
Klein of CSPA told C&EN that antifreeze makers want the mandate for a bittering agent "as prescriptive as possible." From an industry perspective, it is vital that any bitterant added to antifreeze not damage vehicles, he said. Experience in the three states with laws requiring bittering agent in antifreeze has shown that DB will not harm vehicles, he added.
Critics of the legislation also are attacking the liability shield it would provide to antifreeze manufacturers adding DB to their products.
That waiver would assign liability for antifreeze to the companies that make the automotive fluid and liability for DB to producers of the bittering agent, Klein explained. Supporters of the shield say it merely clarifies that liability from any toxicity or environmental damage from DB rests with producers of DB, not with antifreeze makers. According to Rep. Joe Barton (R-Texas), chairman of the Energy & Commerce Committee, suits could still be brought against antifreeze manufacturers for defects in the antifreeze and against bitterant manufacturers for defects in the additive.
Opponents said antifreeze makers should be responsible for their entire product, without an exception for a particular component.
Sens. Barbara Boxer (D-Calif.) and Frank Lautenberg (D-N.J.) see a pollution-prevention angle to the debate. The bittering-agent legislation benefits manufacturers that formulate their antifreeze with ethylene glycol rather than promoting existing nontoxic alternatives, Boxer and Lautenberg said in a March report from the Senate Environment & Public Works Committee on S. 1110.
Most antifreeze makers produce both ethylene glycol-based and less toxic propylene glycol-based antifreeze, Klein said. "There are issues with both types," he added, noting that the price of propylene glycol antifreeze is somewhat higher than that of antifreeze made with ethylene glycol.
The legislation would exempt ethylene glycol-based antifreeze sold in containers of 55 gal or more from the requirement to contain DB. It would also exempt antifreeze that comes with brand-new cars.
Whether or when the bills could come before the full Senate and House is in the hands of Republican leaders. If brought up for a vote, the legislation, billed as protecting puppies and toddlers, likely would pass in both houses. Passage could be a plus for incumbents in the November elections.
Although antifreeze may not rank with war, the economy, or immigration in the public eye, protecting children and pets "does resonate with voters," Amundson said.