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Pfiesteria and Related Harmful Blooms: 97-1047 ENR CONTENTS FOR THIS SECTION
A Larger View
Other Specific Elements of the Federal and Congressional Response. In addition to these coordinated activities, federal agencies and departments also are pursuing specific actions, and Congress has begun to address the issues in several ways. Department of Agriculture Agencies in the USDA are helping Maryland collect information and providing assistance to agricultural producers. These producer assistance programs address agricultural wastes and by-products largely by implementing BMPs. The Natural Resources Conservation Service (NRCS) reportedly will provide an estimated $300,000 under the new Environmental Quality Incentives Program (EQIP) for producers in affected watersheds to develop and implement multi-year conservation plans to implement BMPs and other conservation practices. Agriculture agencies also may give more attention to evaluating the effectiveness of these BMPs. Another action is the October20, 1997, federal approval of Maryland's proposal for the first Conservation Reserve Enhancement Program in the country. The enhancement program, a subset of the Conservation Reserve Program (CRP), is administered by the Farm Service Agency and offers annual rental payments to producers who retire eligible cropland from production for 10 years or more and cost-sharing assistance to install protective vegetation on those lands.9 The enhancement program offers large financial incentives to attract lands that have especially high environmental values. Producers can enroll at any time, in contrast to the CRP, where most land can only be enrolled during designated periods. Under Maryland's enhancement program, the federal government will pay up to 50% of the land value (but not exceeding $600 per acre) to install conservation practices. Maryland will pay up to 37.5% of the land value. Participation targets include 70,000 acres of riparian buffers, up to 10,000 acres of restored wetlands, and up to 20,000 acres of highly erodible land located within 1,000 feet of a water body. Maryland will identify 100,000 eligible acres by the end of 2002. In addition to paying the maximum annual rental rate allowed for these lands under the CRP, USDA will also increase these payments by 70% for land in riparian buffers and by 50% for other land in the enhancement program. Maryland will provide technical support to all applicants, and will establish a program to purchase perpetual easements for these lands as long as the easement terms are consistent with participation in the enhancement program. USDA estimates that the enhancement program will cost the federal government $170 million and Maryland $25 million over the next 15 years. Political leaders view this as a landmark effort, while the farm community is optimistic, but more cautious. Department of Health and Human Services Three agencies in the Department of Health and Human Services are conducting projects and initiating programs relating to Pfiesteria-complex organisms and their human health problems. The Food and Drug Administration's (FDA's) Pfiesteria program consists of two parts. FDA is funding research on testing methods for Pfiesteria toxins. FDA officials hope to characterize the toxins in order to develop methods for testing water at bloom sites. FDA is also assisting both states and foreign countries (e.g., Chile, the Philippines) in developing voluntary "environmental watch" programs among interested citizens that would sound an alert when natural toxins affect water quality and the health of finfish and shellfish. With trained volunteers throughout certain states, FDA is hoping to avoid expensive and, at times, fruitless water and fish sampling. Rather, FDA officials hope to use data collected by volunteers to focus laboratory tests where problems arise from Pfiesteria and other natural toxins. In addition, FDA laboratories respond to state requests for assistance in characterizing natural toxins found in seafood. The Centers for Disease Control and Prevention (CDC) is using a $7 million FY 1998 appropriation to award grants to seven states that have experienced Pfiesteria-related human health effects, so that they can begin to address emerging issues surrounding these health effects. Congressional conferees directed that this funding be used to develop and implement a multi-state disease surveillance system that will identify and monitor health effects in people who may have been exposed to estuarine waters likely to contain Pfiesteria or Pfiesteria-like organisms, to initiate case-control studies when new incidents of illness purported to be due to exposure to the toxins are identified, and to develop a biological test of human exposure (biological marker) so that when the structures of these toxins are identified, a rapid response can be assembled between the CDC and state health departments. The National Institute of Environmental Health Science has begun a $400,000 research project to isolate and chemically characterize Pfiesteria-toxins so that critical exposure levels for health effects associated with human environmental exposures can be estimated and the potential risks to human health can be determined. Department of the Interior. The U. S. Fish and Wildlife Service is targeting state-selected sites for inclusion in an ongoing National Wild Fish Health Survey. Fish collected will be examined for a suite of pathogens and parasites that may be contributing to Pfiesteria-associated problems. The U.S. Geological Survey is seeking to better understand the movement of nutrients into waterways and the relationship between nutrient input from watersheds and water quality in Chesapeake Bay. In addition, recent studies of Chesapeake Bay sediment cores by USGS scientists have confirmed that Pfiesteria-like organisms have existed in the area for at least several thousand years. Congressional Action Congress has taken several steps to address scientific and policy questions concerning Pfiesteria and other potentially harmful aquatic blooms. An oversight hearing on Pfiesteria and its impact on fishery resources was held on October 9, 1997, by the House Resources Subcommittee on Fisheries, Conservation, Wildlife, and Oceans. The House Government Reform and Oversight Subcommittee on Human Resources held an oversight hearing on the federal and state public health response to Pfiesteria on September 25, 1997. Also Representatives Gilchrest (who represents Maryland's eastern shore) and Stenholm hosted a bipartisan forum on phosphorus and water quality at the House Committee on Agriculture on November 3, 1997. Members used information from these sessions to develop legislation authorizing a Pfiesteria research program and research grants (H.R. 2565/S. 1219). The research program proposed in these bills would be administered by EPA, the Department of Commerce, USDA, and Department of Health and Human Services. The Senate Environment and Public Works Committee reported S. 1219 on November 4, 1997 (S. Rept. 105-132). In addition, in appropriations bills for FYI 998, Congress has provided specific funding for Pfiesteria research and related activities. In the bill providing funding for EPA (P.L. 105-65: Departments of Veterans Affairs and Housing and Urban Development, and Independent Agencies Appropriations Act, 1998), Congress appropriated $3 million - $1.5 million for external research, and $1.5 million to support response and monitoring efforts, public information, and cross-agency coordination and analysis. Additionally, that bill earmarked $2 million in grants for sewage treatment plant improvements at plants on the Pocomoke River, Maryland, in response to concerns about pollutants that may be associated with fish kills in that waterbody. Funding to deal specifically with Pfiesteria and related blooms was included in other FY1998 appropriations measures as well. NOAA was provided $3.5 million for Pfiesteria monitoring and assessment activities as well as research on Pfiesteria and other harmful blooms (P.L. 105-119; Departments of Commerce, Justice, and State, the Judiciary, and Related Agencies Appropriations Act, 1998). As previously mentioned, P.L. 105-78 (Departments of Labor, Health and Human Services, and Education, and Related Agencies Appropriations Act, 1998) provided $7 million for CDC's activities to address emerging issues of human health effects from exposure to Pfiesteria. In these FY1998 appropriations measures, Congress sought to develop an appropriate balance between providing funds for defining the Pfiesteria problem (e.g., monitoring waterways) and money appropriated for addressing the concerns arising from Pfiesteria-like events (e.g., culturing the organisms, isolating and characterizing the toxins, developing diagnostic tests). Altogether, about $13.5 million was appropriated for Pfiesteria-related activities in FY1998.
Water Quality Management Issues From a water quality perspective, specific pollution problems such as Pfiesteria, where they occur, may reflect a larger set of issues. if the scientific theories regarding the organism are proven to be correct, some of the water quality conditions that may be associated with its emergence - nutrient enrichment, in particular - also contribute to water pollution problems generally in the same areas and others nationwide. Nutrient over-enrichment of waters and algae blooms can depress oxygen levels and lead to fish kills, even where Pfiesteria is not present. From that perspective, Pfiesteria is not a singular problem. It is only one example of the challenge to improve quality in waters that experience nutrient enrichment, often from numerous sources. It does, however, represent the first instance where the public has associated human health risks with elevated nutrient levels in estuaries. Data reported by states to EPA indicate that nutrients and bacteria are the leading causes of pollution in estuaries, where Pfiesteria has primarily been found, and that the principal sources of that pollution are urban runoff (discharges from storm sewers), municipal sewage treatment plants, septic systems, air deposition (motor vehicle exhaust and smokestacks, for example), and agriculture. It is difficult to determine which specific sources may be contributing to the conditions where Pfiesteria apparently thrives and other water quality problems exist. Thus, the first challenge for water quality managers is to assess point and nonpoint sources to quantify environmental effects of particular discharges, on a case-by-case basis. However, because many scientists consider the linkage between nutrient pollution and Pfiesteria outbreaks to be uncertain, most scientists and resource managers do not believe that nutrient reduction alone will eliminate Pfiesteria problems. Nutrients alone may not be causing the problem, but they are one possible factor that humans can control through technology and management practices which affect land use. Further reduction in nutrient loads to aquatic systems may be beneficial for multiple reasons, but such actions do not guarantee solving the complex Pfiesteria problem. Thus, while nutrient reduction may be significant to achieving overall water quality improvements, it is too soon to know with any certainty how significant nutrient reduction might be in specifically addressing Pfiesteria and problems similar to it. If sewage treatment plant discharges are implicated, permitting officials may tighten existing discharge limits in National Pollutant Discharge Elimination System (NPDES) permits which will result in added technological controls. If runoff from farms or city streets is implicated, management is more complicated because, under current federal law (the Clean Water Act), these sources are regulated either by permitting or other programs, depending upon the size of the source. Generally, runoff from large animal feedlot operations (those with more than 1,000 animal units) and larger cities (those with populations greater than 100,000 persons) are regulated by NPDES permits. Runoff from other farms and smaller animal feedlot operations and cities are subject primarily to state-run management programs that rely largely on voluntary efforts to minimize runoff The runoff from animal feedlot operations and smaller cities can be subject to NPDES permit requirements if the permitting authority so desires; however, many state NPDES authorities still use voluntary state-run programs for these sources. Reauthorization of the Clean Water Act, which could occur in the 2nd Session of the 105th Congress, may give policymakers opportunities to consider what role that Act, and possible amendments to it, might play in addressing Pfiesteria-related and similar water pollution problems.10 In particular, the effectiveness of voluntary programs to manage nonpoint sources of pollution may be an issue. Similarly, policymakers may consider whether changes to the law's existing regulation of municipal, industrial, and agricultural point sources are needed to remedy coastal water quality degradation and conditions that may be associated with Pfiesteria outbreaks.
Runoff or discharge of nutrients from animal production facilities (both open and confined) have been implicated in "Pfiesteria problems" in Maryland and North Carolina waters. Prior outbreaks in North Carolina have occurred in rural watersheds where agriculture dominates. In Maryland, suspicion is widespread that areas with concentrated livestock operations and large volumes of waste, particularly poultry farms on Maryland's eastern shore, may be important contributors of dissolved nutrients that could trigger rapid population growth by toxin-producing dinoflagellates. Manure is not the only possible agricultural source, since excessive application of commercial fertilizers can also cause nutrient enrichment of water. The Maryland Department of Agriculture has gathered information to characterize agriculture in the Pocomoke River drainage, the largest of the "Pfiesteria problem"watersheds, more precisely. 11 Evaluators surveyed 129 of the 543 agricultural producers in the drainage. These producers manage more than 50,000 acres, less than a third of the 170,000 acres of cropland in the drainage. The survey revealed that corn or soybeans are grown on more than 80% of the crop acreage covered in the survey. Two-thirds of the producers in the drainage (366) raise poultry; these farmers raise 29 million birds annually. In addition, there are 17 swine, 17 livestock, and 2 dairy operations. Conservation practices are widely followed by the surveyed producers. More than 75% of crop producers have a soil conservation and water quality plan, and more than 70% cultivate their cropland under conservation or no-till systems. About 56% of the survey participants use nutrient management plans (about the statewide average), making these plans the third most common BMP after crop rotation and animal waste storage structures. On-site evaluations of the surveyed producers showed that almost 90% receive federal and/or state cost-sharing to implement BMPs in accordance with their plans. Most BMPs have been installed during the past decade. On-site evaluators concluded that 68% of the farmers were providing comprehensive protection to their farms using BMPs, and did not have any readily identifiable pollution problems. Regarding animal waste management, the survey found that manure was being applied on 42% of the cropland, and that 85% of the crop producers were applying manure to cropland. Almost two-thirds of the producers receive at least a portion of their manure from someone else, and 22% of the farmers transfer all their manure to others. Almost three-quarters of the livestock producers use an animal waste storage facility; the remainder apply it directly to the fields or temporarily stockpile it. The top factor influencing a farmer's decision about when to apply manure to crops was the nutrient management plan, identified by 42% of the participants. These data indicate relatively widespread conformance with accepted conservation practices and participation in conservation programs. If it is determined that excessive nutrients from farm activities are significant in causing the Pfiesteria related problems, then it seems unlikely that the current approach to BMPs and voluntary participation would provide a satisfactory reduction in nutrients. Nutrient management plans on most farms reportedly have focused on managing nitrogen, under the assumption that effectively managing nitrogen means that phosphorous is managed as well. But research indicates that soils can become saturated with phosphorous as a result of applying animal manures to meet nitrogen need, and that phosphorous can be lost to surface and ground water when soils are saturated with this element, even when nitrogen guidelines are being met. The NRCS is revising its nutrient management policy to address all nutrients rather than just nitrogen. The new policy will require access to adequate amounts of land to dispose of the phosphorous. This change will result in less manure being applied to some fields where phosphorus is already excessive. 12 This, in turn, will increase the supply of surplus manure in some watersheds. Group and community action, and probably some innovative approaches, may be required to address some of these problems. Approaches that scientists are examining include long-distance shipping, composting, burning, and using biotechnology to improve animal feeds. On October 29, 1997, the poultry industry announced a 4-year research program costing $1 million and aimed at curbing pollution from agriculture. 13 This proactive proposal has reportedly been greeted with skepticism by some who believe that the magnitude of the effort is less than commensurate with the magnitude of poultry's role in nutrient enrichment. As discussed above, large confined animal feeding operations (CAFOs, feedlots with more than 1,000 animal units) are subject to discharge permit requirements under the Clean Water Act, and other animal feeding operations may be designated as CAFOs if they pose a threat to water quality or use. The regulatory requirements for CAFOs generally prohibit discharge of waste water pollutants into navigable waters. Still, unpermitted waste discharges and spills from feedlots in a number of states, and the recent attention to Pfiesteria, have raised questions about the adequacy of regulation and enforcement and whether the size threshold for CAFOs should be lowered to bring more operations under regulation. Several states have enacted or are considering measures that would impose additional waste management controls on animal production facilities, beyond current federal rules. Agricultural interests continue to hold that no scientific evidence proves that farm activities cause or even contribute to toxic dinofiagellate blooms. They also cite the Maryland Department of Agriculture survey to back their claim that most producers in these watersheds (at least in Maryland) participate in voluntary programs to implement conservation plans and properly install and maintain BMPs. But no data show how the installation, maintenance, or operation of these practices have affected water quality. Because of the lack of information about the causes of these outbreaks, agricultural interests believe that they have been unfairly singled out before the full dimensions of the problem and its more effective solutions are known. Even if nutrient enrichment from poultry farms turns out to be at the heart of this problem, decreased nutrient contributions from farms may not reduce the problems for several years. Critics believe that agricultural activities are either the primary cause of toxic dinofiagellate blooms or are a major contributing factor. They believe that stronger management of manure could improve water quality, and that stricter pollution control regulations combined with more effective enforcement is necessary. Given the severity of the problem, many advocate immediate action, even though research to assess the causes of this problem has not been completed. Maryland's Blue-Ribbon Panel rejected some proposals for stronger controls, such as limiting overall chicken production throughout the state, but recommended new pollution control measures that would have to be enacted by the Maryland legislature. 14
Scientists still need to document which and how many dinoflagellate species produce toxins that are potentially harmful to humans. Research is needed to determine which species may occur in high risk areas that are currently associated with fish kills, disease, and human ailments. Until scientists identify the number of toxic species involved, the active ingredients in these species' toxins, and the toxins' modes of action, and characterize the organisms' life cycles, there remain many unanswered questions about their potency and how they could affect human health. For example, no human illnesses have been reported after eating Pfiesteria-stricken fish, so it is unknown whether the toxins accumulate in seafood, affect human internal organs, or may be destroyed during cooking. There is concern that shellfish, particularly filter feeders such as oysters and clams, could harbor Pfiesteria and the toxins. Two FDA studies of oysters that were exposed for one week to heavy doses of Pfiesteria toxins established no association with the toxins. It is unclear whether the toxins break down or are diluted in the air or water. However, the toxicity appears to dissipate quickly. It is also unclear how many different dinofiagellate species or other organisms may be producing toxins. There could also be variations in the toxins. It is clear that exposure to these toxins poses a health risk, but the boundaries of that risk have not been identified. Until some of these questions are answered, it is difficult to assess the implications of these recent fish kills on human health.
Fisheries and Estuarine Ecosystem Issues
Estuarine Ecosystem. Little concern has been raised that Pfiesteria-like blooms could harm the reproductive success of economically important fish stocks, and there has been no reported reduction in menhaden or other affected fish stocks. In addition, it is unknown whether pre-existing conditions within fish populations, such as weakened immune systems, could make menhaden more susceptible to toxins from Pfiesteria-like species. Limited information is available on the habits and habitats of Pfiesteria and related species, and little is known about how this organism may spread between estuaries, particularly whether ballast water or the transport of fish products may be factors in spreading these species. Until the identity of organisms responsible for the recent fish kills is determined conclusively, considerable doubt remains as to how best to address human health and resource concerns. The life cycle of Pfiesteria-like species is not well known, and what triggers Pfiesteria-like organisms to transform between different toxic and non-toxic life stages is not well understood. In addition, potential control mechanisms have not been widely discussed, including the potential for suppressing blooms by chemical control, aeration, clay particles, or other means. Are there natural environmental features, including competing plankton populations, that could be manipulated to control Pfiesteria or cause it to return to or remain in non-toxic forms? In addition to the potential impacts of Pfiesteria-like organisms, the roles of other components of estuarine ecosystems, such as bacteria, viruses, parasites, and non-dinofiagellate planktonic organisms, may also need to be assessed. Focusing concern on one component (i.e., Pfiesteria-like organisms) of an entire ecosystem may fail to identif~ or eliminate other causes for fish kills and poor fish health. Such short-sightedness could be costly in terms of inadequate and possibly inappropriate research efforts and ineffective and misdirected corrective measures. Commercial Fishing. The main effects on commercial fishing result from the closure of sections of estuaries to minimize contact with possible Pfiesteria toxins. However, a study by the North Carolina Department of Environment and Natural Resources 15 found that, although commercial fishermen were forced to change their behavior when sections of the Neuse Rivers were closed, the economic impacts on those fishermen were minimal, because they were able to adjust harvesting location.. Retail Seafood. The retail seafood industry has been affected in two ways: 1) river closures may restrict the supply of local seafood to retailers, ultimately resulting in higher seafood prices and less seafood sold at the retail level; and 2) decreased consumer confidence in the quality of local seafood which causes consumers to demand less seafood, resulting in a decrease in sales and a decrease in prices at the retail level. This decrease in demand may occur regardless of the ultimate findings on human health effects and quality of seafood. The intense media coverage of Pfiesteria in both North Carolina and Maryland diminished consumer confidence in seafood, despite public relations efforts of state officials. The logical conclusion would be an ambiguous effect on the retail price of seafood (depending on whether the supply or demand shock had more impact) and an unambiguous decrease in seafood retail sales. State and federal managers have generally taken a conservative approach to questions of whether Pfiesteria-like species may pose any concern for seafood safety. Maryland managers prohibited all commercial and recreational fishing in affected waters, and have advised citizens not to consume fish with lesions or those that appear to be diseased. Although no instances of tainted seafood or human illness from eating fish exposed to Pfiesteria have been reported, health officials advise caution since so little is known about Pfiesteria. Commercial and economic interests, however, remain concerned that the occurrence of Pfiesteria diminishes consumer confidence in seafood safety generally, and that consumers may make broad assumptions about seafood sanitation and quality leading them to reject safe seafood. In Maryland, anecdotal information suggests that seafood sales may have declined as much as 45-50% by late September/early October 1997.16 The issues to be addressed are whether additional efforts may be necessary to promote seafood safety when Pfiesteria is present and to assist the seafood industry in addressing consumer confidence concerns with seafood. Recreation and Tourism. River closures and concerns about water quality have negatively affected recreational users and tourism in general. As river users and tourists shift their activities away from questionable locations (unless closures are widespread), local tourism-dependent businesses experience a decline in revenues.
Concern has been expressed worldwide that harmful aquatic blooms may be increasing in frequency and severity. 17 Others question this conclusion, suggesting rather that our improved ability to detect and report such events has only made their occurrence more apparent. While many initially presumed that Pfiesteria or related organisms were the problem and that farming practices were the cause, state and federal agencies have conceptualized a coordinated response that focuses broadly on gaining the scientific data necessary to better understanding this problem and how to address its effects. Fish kills regularly occur, for numerous reasons - water quality, net dumping, infectious agents, harmful blooms, chemical contaminants, et al All of these factors are relevant and need to be considered when addressing recent fish kills. In addition, many small dinofiagellate species inhabit coastal and estuarine waters. Some of these species produce toxins that cause fish kills and pose public health risks. It is unwise to assume that Pfiesteria or morphologically similar organisms have caused all the recent events. Thus, it will likely require a multi-faceted, multi-agency approach to address all the factors related to recent fish kills, disease, and human health risks.
Selected Sites About Pfiesteria on the World Wide Web
Endnotes 9 Slightly more than 19,000 acres in Maryland are currently enrolled in the Conservation Reserve Program -- a very small portion (1.2%) of the 1.6 million acres of cropland in the state. 10 For additional information, see CR5 Report 1B97001, Clean Water Act Reauthorization in the 105th Congress. 11 Maryland Department of Agriculture. Preliminary Characterization ofAgriculture in the Pocomoke Watershed. Annapolis, MD: October 1997. 16 p. 12 Tom Simpson, coordinator of Chesapeake Bay Agriculture Programs for the Maryland Department of Agriculture, pointed out during his presentation at the House Agriculture Committee forum on Nov. 3, 1997, that more than 90% of the soils in Maryland's lower eastern shore are at or above optimum levels for phosphorous. 13 "Poultry Group Offers $1 Million for Study." Washington Post, Oct.30, 1997, p. D4. 14 The Blue Ribbon Panel's final report contains discussions of agricultural topics. In addition to the text of the report, several appendices provide additional insights. 15 Diaby, S. The Economic Impacts ofNeuse River Closures on Commercial Fisheries. North Carolina Department of Environment and Natural Resources, 1996. 16 Yost, Mark. "Pftesteria Outbreak Hurts Economies of Chesapeake Bay." Dow Jones News Service, October 7, 1997. 17 For example, see: Donald M. Anderson, "Red Tides," Scientific American, v.271 (August 1994): 62-68; Jeremy Curfews, "The Fringe of the Ocean Under Siege from Land," Science, V. 248 (Apr.13, 1990): 163-165; and Elizabeth Culotte, "Red Menace in the World's Oceans," Science, v.257 (Sept. 11, 1992): 1476-1477.
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