Anthropogenic nitrate in Chinese groundwater ... - ACS Publications

Reports of a “toxic soup” flooding the streets of New ... center of New Orleans as well as from outside parishes ... Service, points out that the ...
0 downloads 0 Views 309KB Size
Environmental t News New Orleans soils get clean bill of health—almost

6868 n Environmental Science & Technology / November 15, 2006

© 2006 American Chemical Society

USGS

R

eports of a “toxic soup” for fragrances, newer pesticides, pears in mine tailings, and it has the flooding the streets of New and cholesterols, they used novel potential to oxidize, leading to acidOrleans and the surrounding methods. Zinc, PCBs, and DDT, ic runoff. Plumlee suggested that a region surfaced in the aftermath of among other compounds, apsmall chance exists that this could Hurricane Katrina. But a year afpeared in mud and lake-sediment occur in soils in the region, but he ter the disaster, scientists from the samples at the mouths of several added that it would take years, deU.S. Geological Survey (USGS) and canals. High concentrations at pending on how the soil is exposed. elsewhere conclude that the water many sites dissipated weeks after High levels of arsenic and lead, that coursed through the city and the soils that remain hold few surprises. They say that most contamination that could pose concerns lingered in urban areas since before the hurricane. Samples collected before and after Hurricane Katrina showed some hot spots, but overall, the region After Hurricane Katrina flooded the city, researchers looking for pollutants collected samples from seems to be below New Orleans's canals and the shoreline of Lake Pontchartrain (shown here in this satellite image toxic regulatory levels from September 2, 2005). for many of the metals and compounds tested. Even the hurricane passed. Lake Pont­ as well as cadmium and other metwater-column and sediment samchartrain “is big enough and the als, showed up in soil samples from ples from Lake Pontchartrain have circulation is strong enough in and downtown New Orleans, but many turned out to be relatively benign, out of the Gulf of Mexico” to dissiwere similar to historic levels meaaccording to research published in pate those inputs, Van Metre says. sured pre-Katrina, Plumlee said. Bill this issue of ES&T (pp 6894–6902). In some places on land, HurriForeman of USGS, also a coauthor “Compared to lake sediments cane Katrina dumped many cenon the ES&T paper, reported at the all over the country, Lake Pont­ timeters of sludge, which was the ACS meeting that dieldrin (banned chartrain sediments are similar,” consistency of chocolate frosting, in the 1970s) and other pesticides says Peter Van Metre of USGS, says Geoff Plumlee of USGS. At the used for treating termites had high who is the lead author of the ES&T September meeting of the Ameriresidues in urban areas. In some research. “There’s a lot of urban can Chemical Society (ACS), he downtown “hot spots,” Foreman contamination, and Lake Pont­ presented results from the urban said, dieldrin hit 46–92 micrograms chartrain is typical of that.” Still, center of New Orleans as well as per kilogram. Benzo[a]pyrene, a Van Metre and his colleagues from outside parishes that showed PAH from combustion, exceeded found that pollutants were cona wide range of contaminant levels. U.S. EPA levels downtown and in centrated at the mouth of the 17th In Chalmette, for example, the samsome residential areas, he said. Street Canal, through which much ples had distinct marsh-soil signaIn general, Plumlee emphaof the flood water was pumped out tures, showing that Katrina pulled sized, the levels found outside the of the city. up those soils from marshes and downtown area for metals and The team analyzed mud from dumped them inland, Plumlee said. other potentially hazardous comthe city and sediments from canals The clues to the soil’s identity pounds tended to be below federal and Lake Pontchartrain for a long included tiny framboidal (raspstandards for soil exposures. In list of possible urban contamiberry-shaped) grains of pyrite. The the urban center, lead levels were nants. In some cases, particularly iron–sulfide mineral generally apthe most elevated—the residue of

Still, Mielke sees the hurricane as an opportunity to advocate remediation that dovetails with the posthurricane cleanup. He suggests a central distribution center with clean soil to dump atop the lead-contaminated areas in the center of the city. Sven Rodenbeck, an environmental engineer and commissioned officer in the U.S. Public Health Service, points out that the historic parts of New Orleans were farthest from the levees breached. “As far as moving existing contamination, the strength of floodwaters [had] pretty much dissipated” by the time they reached those sites. Environmental groups have disagreed with EPA and other organizations on this point ever since the disaster. Still, “with the exclusion of the Murphy Oil spill,” southwest of the city, Rodenbeck says, “the floodwaters did not result in any widespread contamination of the New Orleans area.” —NAOMI LUBICK

Anthropogenic nitrate in Chinese groundwater Tracing nitrate contamination to its source often proves difficult and requires sophisticated methods. New research published in this issue of ES&T (pp 6928–6933) combines multiple isotope ratios to identify local sources of nitrate in an aquifer in southwest China. The method allowed scientists to tease apart two very different sources of nitrate in groundwater by considering which dominates in winter and which in summer. They could also conclude that karst aquifers cannot recover quickly from human sources of nitrogen. Nitrate is highly water-soluble and can easily enter groundwater, which is a major source for drinking water. Elevated concentrations

of nitrate in drinking water have been of concern because of its human health effects. “Nitrate content of only 5 times above that of natural background [levels], about 2 milligrams per liter [mg/L], can be toxic to infants and create longterm health problems in adults,” says Samuel Panno, with the Illinois State Geological Survey. Longterm exposure through drinking water can lead to human health impacts that include diuresis and hemorrhaging of the spleen, for example. Therefore, Panno says, “understanding the nitrate cycle is important for understanding where nitrate is coming from, how it is being transported, and how it evolves and reacts in the

News Briefs Earth as a different planet

Earth is the warmest it has been in the past 10,000 years, according to a new analysis that warns of serious changes ahead. Global surface temperature has increased by about 0.2 °C per decade in the past 30 years, researchers note in the September 25 issue of Proceedings of the National Academy of Sciences (2006, 103, 14,288–14,293). The paper, by James Hansen of NASA’s Goddard Institute for Space Studies and colleagues from Columbia University Earth Institute, predicts that if temperatures rise 1 °C, changes will occur rapidly and result in a “different” planet. “Given that a large portion of human-made CO2 will remain in the air for many centuries, sensible policies must focus on devising energy strategies that greatly reduce CO2 emissions,” the team concludes.

U.S. offers a plan for climate technologies

After a 4-year wait, the Bush Administration released its plan to encourage voluntary reductions of climate-affecting gases. Introduced mid-September, the U.S. Climate Change Technology Program Strategic Plan takes a long-term view of technological development and describes Bush’s $3 billion program for encouraging technology that might slow climate change. Several programs are already under way at U.S. Department of Energy labs. One such project is the $1 billion FutureGen, a plan for a coal-fired plant based on coal gasification that is nearly emission-free. Critics, including those on Capitol Hill, point out that Bush’s plan lacks short-term initiatives as well as mandatory requirements. To view the final report, go to www.­ climatetechnology.gov.

November 15, 2006 / Environmental Science & Technology n 6869

JUPITERIMAGES

decades of industrial activity, left behind in historic deposits from paint, industrial applications, and leaded gasoline. In the past decade, Howard Mielke of Xavier University and co-workers showed that the lead in New Orleans’ soil caused high blood-lead levels in children who played on contaminated dirt in the city. By chance, Mielke’s group took soil samples the week before Hurricane Katrina, partly to check the success of a remediation program that included dumping lead-free soil onto those sites. Some tests already had showed a decrease in the blood-lead levels of children playing on the treated sites. With more sampling post-Katrina, Mielke and co-­workers showed that Katrina did not change those historic lead levels. The hurricane neither dumped sediments to cover up the leadbearing soils, nor did it carry them away. The results will appear in ES&T (doi 10.1021/es061294c).

Environmentalt News

COURTESY OF CONGQIANG LIU

tion, or waste. From the isotope the similarities indicate a possible environment.” ratios, they conclude that the main direct and immediate connection The U.S. EPA has set the maxinitrate sources during summer between water above and below mum contaminant level for nitrate are agricultural activities, whereground, or later mixing of fertilizin drinking water at 10 mg/L. The as during winter the main input er-bearing rain with groundwater, limit is 20 mg/L in China, where comes from untreated municipal the authors say. on average about 20% of drinking sewage. The group has conducted rewater comes from groundwater. search on nitrate cycling In northern parts of the in Guiyang for about 4 country and in urban years and found no sigareas, the percentage is nificant variation. “The much higher, says lead big change in nitrate conauthor Congqiang Liu of the State Key Laboratory tent in the groundwater of Environmental Geois just controlled by the chemistry in the Chinese local environment of the Academy of Sciences. sampling sites,” Liu says. Liu and colleagues foBiological denitrificacused on identifying the tion—in which microbes local sources of nitrate break down nitrate—can within and around the occur, to some extent, in rapidly developing city aquifers. However, the of Guiyang, in southwest new research “shows China. Karstic landforms convincingly that the resuch as carbonate limeduction of nitrate loads Summer agricultural runoff sends nitrate into the groundwater stone surround Guiyang, by denitrification is that feeds this spring near Guiyang, China. and these rocks are well quite insignificant in the known to be sensitive karstic terrains,” remarks to pollution. The limestone is disThe researchers also meaBernhard Wehrli, a professor in solved by rain and groundwater, so sured concentrations of chloride aquatic chemistry at the Swiss that sinkholes and underground and other elements, such as magFederal Institute of Aquatic Sciconduits are created through nesium and calcium, comparing ence and Technology (Eawag). which surface water can flow relathese levels in surface water and Human activities, Wehrli notes, tively unhindered. groundwater to those in an unsuch as “the production of nitroTo fingerprint the nitrate in treated wastewater sample. The gen-[based] fertilizers and the oxithe karst groundwater, Liu’s team chloride concentrations, in pardative nitrogen fixation by burning analyzed nitrogen and oxygen isoticular, were similar in all three fossil fuels, have doubled the protopes, which differ according to source types. The nitrate/chloride duction of bioavailable nitrogen their source, whether from biologiratio in groundwater mirrored surspecies on a global scale.” cal activity, atmospheric deposiface-water ratios in the summer; —THANH WANG

Keeping up with its reputation as a leader in environmental protection, California plans to launch a biomonitoring program to measure the chemical load in residents across the state. The California Environmental Contaminant Biomonitoring Program, signed into law by Gov. Arnold Schwarzenegger (R) on September 29, will be the first statesponsored effort in the U.S. Periodically measuring certain biomarkers in humans can indicate long-term exposure to chemi-

cals, and the results can be useful when setting priorities for which chemicals to control. The data help to identify trends—for example, in at-risk populations—and to determine whether prevention methods or regulations have had their intended effects, according to the Centers for Disease Control and Prevention (CDC). Public-health specialists and epidemiologists say that biomonitoring is gaining in importance, especially as small-scale, locally

6870 n Environmental Science & Technology / November 15, 2006

BRE AST CANCER FUND

Measuring chemicals in Californians

Gov. Arnold Schwarzenegger (R) signed a bill on September 29 establishing a California-wide biomonitoring program to track chemicals in humans for publichealth and regulatory issues.

focused initiatives. A program tracking several thousand people in New York City, for example,

to provide funding for the program next year, says Gretchen Lee with the Breast Cancer Fund, a nonprofit activist organization that assisted in drafting the bill. The list of compounds to be monitored could also go beyond the 400-plus currently in NHANES, Lee says, to “look at chemicals of concern [that are] unique to California.” In the West, most states expect to find evidence of a long list of human-health-threatening compounds, including phthalates, PCBs, and pesticides, due to heavy agricultural chemical use as well as exposures in industrial and home settings, says David Mills, the head of the New Mexico state health laboratory. Mills and others suggest that California’s program, if it goes forward, will increase the laboratory capabilities of other states in the Western Tracking and Biomonitoring Collaborative, which includes the 12 westernmost states and Hawaii. It could also provide baseline data for the region. California’s legislation also requires that the data collected be made available to individuals tested, so they can see their own “body burden”. This “right to know” is not incorporated into NHANES and was important to the parties writing the California legislation, says Amy Kyle, a University of California, Berkeley, public-health professor. Despite the availability of individual data, the California program is directed more toward producing results for the state population as a whole rather than neighborhood-level snapshots, Kyle says. She adds that she and others hope the program will be implemented in such a way as to tease out focused information on smaller, highly impacted groups. The American Chemistry Council (ACC), a trade group, opposed the biomonitoring bill when it was introduced 3 years ago. But ACC removed its opposition after the approval of several amendments, including the requirement for a scientific review board. —NAOMI LUBICK

News Briefs Reporting for nanomaterials in U.K.

The British environmental agency launched a voluntary reporting scheme at the end of September to collect information on nanotechnology research from academic and industrial investigators. The program will run for 2 years, and any information submitted is subject to Freedom of Information Act (FOIA) requests. Officials say they plan to use the data to help with policy decisions on nanotechnology issues, including risks and policy controls. In the U.S., companies manufacturing nanomaterials must report their activities under the Toxic Substances Control Act, but only if the product is considered a “new chemical”. Judging whether novel nanomaterials are actually new chemicals remains controversial. If nanomaterials qualify, the U.S. EPA reviews them for toxicity and risk. The information that companies submit in the U.S., however, can be difficult to obtain by FOIA requests.

Nanotechnology knowledge gaps

Nearly 60% of U.S. residents have heard “nothing” or “just a little” about nanotechnology, according to the first nationwide poll on the subject in more than 2 years. Conducted by the independent research firm Peter D. Hart Research Associates and commissioned by the Woodrow Wilson International Center for Scholars Project on Emerging Nanotechnologies, the statistically representative poll of 1014 adults found that among all major U.S. demographic groups, most people willing to take a position on nanotechnology said its risks outweighed its benefits. It also finds that most Americans believe that the federal government (55%) and universities and independent researchers (54%) have a role in overseeing scientific and technological advancements such as nanotechnology.

November 15, 2006 / Environmental Science & Technology n 6871

NASA

uncovered a hidden threat from arsenic contained in illegal skinlightening products, and this led to a public-health campaign and a crackdown on importation, says Dan Kass, director of Environmental Surveillance and Policy for the New York City Department of Health and Mental Hygiene. The nonprofit Washington Toxics Coalition in Seattle has attempted an even more limited study—monitoring nine people—in an attempt to introduce the concept there. The federal biomonitoring program, part of the larger program of environmental health monitoring known as NHANES (National Health and Nutrition Examination Survey), tracks 5000 people in 15 locations around the U.S. Participants give blood samples and have a full medical exam every 2 years. NHANES, which is run by a division within CDC, “does not give regional data. One can’t say what the levels are in California, [even though] the California population may be sampled quite a bit,” says Larry Needham, an epidemiologist with CDC’s National Center for Environmental Health. The countrywide study can only give national views because of the sampling pattern and the statistically based analysis used. Local information remains necessary for epidemiological and health policy decisions, argue supporters of the California bill and other epidemiologists. The California program will be the first state-funded survey independent of the CDC program. CDC will, however, provide guidance on how to run it, including laboratory protocols to enable later comparison with NHANES data. So far, CDC has given grants to New Hampshire, New York City, and a consortium of six western states. California’s legislation doesn’t lay out any details for its program, such as which chemicals will be tracked and who will be tested. A scientific review panel will help make these decisions. The program’s first report to the state is due January 1, 2010. The state legislature is expected

Environmentalt News

Paul Anastas takes green chemistry personally, to the point that he and his wife, Julie ­Zimmerman, purchased CO2 credits for the emis­ sions created by their October wedding. As head of the Green Chemistry Institute at the American Chemical Society, Anastas instituted the same practice for the group’s annual conference. “Why give those cheap plastic trinkets,” he asks, “when the same money could go to ensuring that attendees’ carbon emissions from their travel to the meeting were offset?” Anastas’s persistence in promot­ ing sustainability in chemistry was rewarded by the Heinz Family Foundation, which honored him in October as the “Father of Green Chemistry”. When asked what he

Paul Anastas is honored as the “Father of Green Chemistry”.

JIM HARRISON / HEINZ FAMILY FOUNDATION

Anastas gets Heinz environmental award

will do with the $250,000 prize, Anastas replies half-jokingly, “All I do now with my money is promote green chemistry anyway.” Anastas coauthored the 12 principles of green chemistry in what has been called the seminal book in the field, Green Chemistry: Theory and Practice, and he was the guest editor for a special issue of ES&T on

the principles of green engineering (December 1, 2003). He gives credit to his mentor at the U.S. EPA, the late Roger Garrett, and to the late Joe Breen, the first director of the Green Chemistry Institute, for inspiring him in his work. Anastas says he has been thrilled to see the pharmaceutical industry embrace the principles of sustainability this year in its Green Chemistry Institute Pharmaceutical Roundtable, among other successes in his tenure at the institute since 2004. In January, Anastas will move on to Yale University to lead its new Center for Green Chemistry and Green Engineering. The shift in venue—and the Heinz Award— will not lead to any changes in his philosophy, he says: “You can take me out of the Green Chemistry Institute, but you can’t take green chemistry out of me.” —NAOMI LUBICK

The Essential Resource in Environmental Science and Engineering Now celebrating its 40th Anniversary, Environmental Science & Technology is the most cited journal in Environmental Engineering and the Environmental Sciences and also publishes more articles than any other journal in either category (1,282). Reporting on aspects of the environment and its protection by scientific, engineering, and political means the journal is a unique source of information for scientific and technical professionals in a wide range of environmental disciplines. Environmental Science & Technology publishes contributed material as current research papers, policy analyses, or critical reviews, and news and features providing authoritative news and analysis of the major developments, events, and challenges shaping the field.

Author Benefits and Online Features: ACS Articles on Request author-directed article access

Editor-in-Chief: Jerald Schnoor University of Iowa

ISI® Impact Factor: 4.054 Total Citations: 39,785 For more information, call Member & Subscriber Services: 1-888-338-0012 in U.S. and Canada, or (614) 447-3674 outside North America ISI® Impact Factor and Citations as reported in the 2005 ISI® Journal Citation Reports

The ACS author e-prints program has been extended to allow your article to be accessed without restriction one year after publication via author-directed links or posting on an author’s Web site. For the full ACS Articles on Request Policy, go to http://pubs.acs.org/reprints/policy.html.

Go to http://pubs.acs.org/est to: • • • • • • •

View the Top 20 most-accessed articles Sign up for E-mail Alerts Read articles ahead of the print issue via Articles ASAPSM Examine a sample issue and free abstracts Register as an author and submit your manuscript Register for ACS Publications RSS feeds View ES&T News & Features

6872 n Environmental Science & Technology / November 15, 2006