Miscarriages associated with drinking water disinfection byproducts, study says A California study associating miscarriages with drinking water has raised concerns about current EPA standards for the disinfection byproducts found in virtually all chlorinated water supplies. Conducted by the California Department of Health Services, the study was published in the March issue of Epidemiology (Vol. 9, No. 2, pp. 134-140). By following 5144 women's pregnancy outcomes and recording the quality of their tap water as well as their drinking habits, researchers showed an increased risk of first-trimester miscarriages among women who drank more than 5 glasses of cold tap water a day, if it contained more than 75 micrograms per liter of total trihalomethanes (TTHM). Nearly 16% of these women had miscarriages, but only 9.5% of women exposed to lower amounts of TTHM had miscarriages. The maximum allowable level set for TTHM by EPA is currently 100 micrograms per liter of drinking water. Trihalomethanes constitute a small group of disinfection byproducts that are measured as a group. They are the only byproducts that are widely measured in the United States. TTHM levels therefore serve as an indicator for a much larger group of byproducts that form in water when the chlorine added to destroy harmful bacteria reacts with naturally occurring organic material. "TTHMs are used as a surrogate for all other disinfection byproducts because that's what we have data for," said Frank Bove, senior epidemiologist for the Agency for Toxic Substances and Disease Registry. The trihalomethane indicator chemicals were previously associated with fetotoxicity and spontaneous abortions in human and animal studies. Another recent study, published in January by the Agency for Toxic Substances and Disease Registry, reported that pregnant women in New Jersey who drank tap water containing more than 40 micrograms per liter of TTHM had an increased
risk of having babies with neural tube defects. "Over a half-dozen human studies have consistently found an association between elevated TTHM levels and reproductive defects [including miscarriage]," said Erik Olson, a drinking water specialist for the Natural Resources Defense Council (NRDC). "We're not sure exactly which of the specific disinfection byproducts is of concern," he added. By collecting TTHM data from water-monitoring utilities, the California researchers determined that 18% of the women in their study tapped into water containing more than 75 micrograms of TTHM per liter (although not all of the women consumed tap water). The highest recorded level was 157 micrograms per liter. No data exist on how much of the nation's drinking water supply contains more than 75 micrograms per liter of TTHM, according to Tom Grubbs, regulation manager for EPA's Disinfection Byproducts Rule. The current reporting sys-
tem applies only to municipalities serving more than 10,000 people, and its "exception reporting" rules pinpoint only water systems whose annual average TTHM levels—based on quarterly measurements—exceed more 100 micrograms per liter. The American Water Works Association acknowledged this lack of data. EPA helped fund the California Department of Health Services study, and the agency is currently evaluating the correlation between disinfection byproducts and teratogenicity in other studies. "In and of itself, the [California] study was not conclusive of anything," said Grubbs. "It shows some relationships, but it doesn't prove causality." He cautioned that the levels of disinfection byproducts can vary over time and that they are based on the consumer's location within the distribution system. "Any particular level from any particular system does not necessarily reflect the actual exposure of the individuals in the study," he said. He believes the subject merits further investigation. Results from the California study will not affect the final disinfection byproducts rule antici-
TOXIC SUBSTANCES International heavy metals, POPs protocols finalized Two international protocols designed to control and reduce risks from heavy metals and persistent organic pollutants (POPs) in 43 countries are now expected to be signed in June following negotiations this February in Geneva. Negotiated under the auspices of the United Nations Economic Commission for Europe (UN/ECE), the protocols will be introduced under the UN convention on long-range transboundary air pollution. They represent "the first time that such substances have been dealt with at an international level," according to the UN/ECE, "and will set the basis for legislation in Europe and North America." Under the heavy metals protocol, which targets lead, cadmium, and mercury, signatory countries will have to reduce emissions of the three metals below 1990 levels. The protocol also aims to cut emissions from industrial sources by setting "stringent" limit values and suggesting best available techniques to be used in relevant industries. After much debate, the POPs protocol now covers 16 substances, including 11 pesticides, PCBs, and dioxins, for which signatory countries are to "eliminate discharges, emissions, and losses." One notable absence from the POPs protocol is pentachlorophenol, which is mentioned instead as an "area for research," according to the UN/ECE. Both measures are due to be formally signed at the 4th Pan-European conference of environment ministers this June in Arhus, Denmark. —Reprinted with permission from ENDS Environment Daily, Environmental Data Services, Ltd., London (http://www.ends.co.uk,
[email protected])
APRIL 1, 1998 / ENVIRONMENTAL SCIENCE & TECHNOLOGY / NEWS • 1 6 9 A
pated this November, according to Grubbs. That rule will lower the maximum admissible level of TTHM, which is regulated as a chronic toxin, to 80 micrograms per liter, he said. It will also extend the requirement to all drinking water providers, not just
those supplying more than 10,000 people. Olson of the NRDC says that, in light of current studies, his organization may press EPA to reconsider TTHM's status as a chronic toxin. "We probably need to reopen the debate as to
EPA's 1999 budget request highlights climate change, water quality programs EPA administrator Carol Browner requested Congress to grant EPA a 6%, or $400 million, budget boost, which would provide the agency with $7.8 billion in 1999. The budget reflects several new policy directions for EPA, including $230.6 million for climate change, which doubles the amount Congress approved in 1998, and an additional $8 million, or $33 million total, to implement its children's health agenda. Browner said the largest increase is sought for climate change activities. "This budget reflects [President Clinton's] determination that America shall lead the world in meeting the challenge of global warming," she said. This year the agency fundamentally changed the way it prepares a budget, in keeping with the provisions of the Government Performance and Results Act. This budget is organized around 10 goals, including clean air, safe food, pollution prevention and risk reduction, and better waste management and restoration of contaminated sites. Funding for individual programs is divided among several goals. The budget request for science and technology activities remains relatively stagnant at $633 million—less than a 1% increase from the $631 million Congress approved for 1998. Browner is requesting $21 million for global change science and technology work, although Congress provided only $14 million for those activities last year. Another $1.5 million is sought for the Pfiesteria research program, which will provide grants for universities around the country. The new science and research center under construction at Research Triangle
Park, N.C., would benefit from the $35 million Browner requested. The Office of Research and Development's funding drops slightly under Browner's budget; it would be $485 million, down from the $533 million that Congress approved last year. Browner requested $2.1 billion for the Superfund program, including $91 million for contaminated urban brownfields development, and an additional $650 million, which EPA predicts will speed the cleanup of 900 superfund sites by 2001. Last year, Congress agreed to spend the $650 million only if the program was significantly overhauled, which has not happened. An additional $116 million is requested for global climate activ-
whether we need to regulate TTHMs as acute or short-term exposure risks," he said, pointing out that TTHM levels tend to increase by 1.5-2 times in the summer. "We may be totally overlooking the risk of short-term exposure." —KELLYN S. BETTS
ities, bringing the total EPA expenditure up to $230 million. Air programs would see a $17 million increase under Browner's budget: she is asking for $507 million total, including $75 million to implement the new ozone and particulate matter standards and $65.7 million to develop a national particulate matter monitoring network. The water quality programs would see one of the few drops in this request. Although Browner asked for $145 million in new funds for her clean water action plan (see story on p. 166A), the total budget request is $2.8 billion, down from the $3.1 billion Congress approved in 1998. Drinking water programs would see a $21 million increase, up to $1 billion total. Congressional hearings on the budget request were scheduled for early spring. —CATHERINE M. COONEY
WASTE MANAGEMENT EU Parliament strengthens draft landfill law The European Parliament voted on Feb. 19 to significantly strengthen a draft European Union (EU) directive on landfilling of waste. Members backed tough targets to cut the amount of biodegradable municipal waste sent to landfills, setting the Parliament on a collision course with EU environment ministers who favor less stringent targets. The draft directive requires a gradual reduction in the total proportion of biodegradable waste going to landfills. Parliament voted to limit the amount of landfilled biodegradable waste to 75% of 1993 levels by 2002, 50% by 2005, and 25% by 2010. Environment ministers have endorsed weaker targets. Last December, they informally agreed that countries should cut biodegradable waste being landfilled to 75% of 1995 levels by 2006, 50% by 2009, and 35% by 2016. The landfill directive is expected to have the largest impact on waste management practices in the United Kingdom, Ireland, and the southern EU countries, which have not already put in place measures to pretreat wastes or to reduce the quantity of biodegradable waste going to landfills. Industry observers predict that the directive would also encourage greater use of incineration. If the directive is approved by ministers, it will go into effect in June 2000. —Reprinted with permission from ENDS Environment Daily, Environmental Data Services, Ltd., London (http://www.ends.co.uk, e-mail
[email protected])
1 7 0 A • APRIL 1, 1998 / ENVIRONMENTAL SCIENCE & TECHNOLOGY / NEWS
