Comments on the Proposed Effluent Guidelines for Concentrated Animal Feeding Operations, EPA Docket No. Docket Number OW-00-27

We appreciate the opportunity to comment on the proposed effluent regulations for Concentrated Animal Feeding Operations (CAFOs), as published by the Environmental Protection Agency (EPA). These comments focus specifically on issues of pathogens and antibiotics in livestock waste, which EPA fails to address in its proposal. (Separate comments submitted to this docket by some of the signatories to these comments address additional issues in the CAFO proposal.)

The scientific literature demonstrates that pathogens and antibiotics from CAFO wastes currently pollute surface and ground waters of the United States and represent a public health threat. As EPA notes, "the stated goal of the Clean Water Act is to eliminate the discharge of pollutants into the Nation’s waters" (Preamble to Proposed Rule (hereinafter cited as "Preamble"), section VIII, 66 Fed. Reg. 3052). It would be arbitrary and capricious for EPA to fail to address pathogens and antibiotics in the final CAFO effluent guidelines. We strongly encourage the agency to develop appropriate provisions for inclusion in the final rule, as described in section VII below.

II. Description of commenters

Environmental Defense is a nonprofit advocacy organization with over 300,000 members. Founded in 1967, Environmental Defense has a longstanding interest in environmental issues affecting human health, including agricultural use of antibiotics. Environmental Defense members live, work, and recreate in communities affected by CAFOs, including but not limited to exposure from pathogens and antibiotics released from CAFOs.

Physicians for Social Responsibility is a nonprofit organization representing more than 20,000 physicians and health care providers who are concerned about the nontherapeutic use of antibiotics in healthy animals in CAFOs leading to increased development of antibiotic resistance in humans. Antibiotics are some of the most powerful tools that health care providers have to combat serious infections. Eliminating practices which lead to increased development of antibiotic resistance is a priority.

The Humane Society of the United States is the nation’s largest animal protection organization, with more than seven million constituents. We advocate for humane sustainable farming systems that protect the well-being of animals, while being sensitive to impacts on family farmers, rural communities, public health and the environment. Together with consumers, farmers, legislators, and other non-profit organizations, we are working to address problems associated with Concentrated Animal Feeding Operations including, but not limited, to antimicrobial use and antimicrobial-resistant pathogens

Food Animal Concerns Trust (FACT), organized in 1982, is a non-profit organization that advocates for animal husbandry practices that will improve the safety of meat, milk and eggs. FACT's Food Safety Program makes recommendations to the federal regulatory agencies based on its review of the scientific literature. FACT's On-Farm Research Program develops husbandry methods that improve food safety, are humane, and reduce pollution.

The Institute for Agriculture and Trade Policy (IATP) defines its mission as working globally to promote resilient family farms, rural communities and ecosystems through research and education, science and technology, and advocacy. IATP works toward local, regional, national and international policies that will: shape a more equitable and democratic world economy; promote socially and ecologically sustainable development; ensure environmental protection, biodiversity and food security; value human rights; and strengthen local and regional economies.

Consumer Federation of America (CFA) has been providing consumers a voice in decisions that affect their lives since 1968. CFA’s 285 member organizations from throughout the nation have a combined membership exceeding 50 million people. CFA conducts a variety of advocacy and educational initiatives on health, agricultural, environmental and other issues.

Center for Science in the Public Interest (CSPI) is a non-profit consumer advocacy organization that conducts innovative programs in health and the environment. It provides objective information to the public; represents

citizens' interests before legislative, regulatory, and judicial bodies; and works to ensure that advances in science are used for the public's good. CSPI is supported in part by more than 800,000 subscribers to its Nutrition Action Healthletter, the nation's largest-circulation health newsletter.

III. CAFO wastes contain enormous quantities of both pathogens and antibiotics

The amount of animal waste produced by CAFOs each year is prodigious, exceeding two trillion pounds annually by some estimates. Bacterial and other human pathogens isolated in fecal matter produced by animal facilities include E. coli, Salmonella, Campylobacter, Enterococci, Streptococcus faecium, Streptococcus faecalis, Cryptosporidium parvum, and Giardia lamblia (Sobsey, 2001; Krapac et al., 2000; Utah Department of Environmental Quality 1999; Center for Disease Control 1998; Khachatourians 1998; Krapac et al., 1998). Concentrations of fecal indicator bacteria and some enteric bacteria, such as fecal coliforms and Salmonella, in swine waste can be higher than levels found in human feces (Sobsey, 2001). Hill and Sobsey (1998) found that fecal coliforms in effluent from an anaerobic manure lagoon had a geometric mean concentration of 3.3 x 10⁵ colony forming units (cfu) per 100 ml of effluent; this level exceeds federal guidelines for the land application of municipal wastewater. The concentration in raw swine wastewater was even higher. In short, CAFO wastes contain enormous quantities of potentially harmful pathogens.

CAFO wastes also contain substantial quantities of antibiotics. The vast majority of the antibiotics used in the United States are used in animal production (Mellon et al., 2001) and the presence of antibiotics in livestock waste is well documented. Meyer et al. (2001) detected tetracyclines in the 13 liquid hog lagoon samples that these scientists screened. Thurman and Hostetler (2000) found antibiotics in animal feedlot wastewater and groundwater near lagoons, and the Centers for Disease Control and Prevention (1998) identified four different types of antibiotics in liquefied manure from seven earthen swine waste lagoons. As discussed later in these comments, the presence of antibiotics in CAFO wastes contributes to human health threats from antibiotic resistant pathogens.

Microbes demonstrating resistance to antibiotics have also been isolated from livestock waste. For example, the Utah Department of Environmental Quality (1999) isolated Enterococci from swine sewage lagoons that were significantly more antibiotic resistant than those from a river or private wells. Antibiotic resistant E. coli have been detected in manure from intensive livestock operations (Khachatourians 1998). Some of these antibiotic resistant bacteria may be human pathogens, while others may transfer their resistance genes to human pathogens and thus contribute to human health threats from antibiotic resistant pathogens.

Pathogens and antibiotics from CAFO wastes enter both surface and ground waters, and constitute pollutants subject to control under the Clean Water Act. Although the Clean Water Act focuses on surface water, we strongly support EPA’s interpretation of the Act as providing the Agency with jurisdiction over surface water and ground water that has a direct hydrologic connection to surface water (Preamble, section VII, 66 Fed. Reg. 3015). As noted by the United States Geological Survey (USGS, 1998), nearly all surface water interacts with ground water and it is "increasingly important to manage ground water and surface water as a single entity."

As EPA notes in the preamble to the proposed CAFO rules, pathogens and antibiotics from livestock waste can reach surface waters by a number of different pathways (Preamble, section V, 66 Fed. Reg. 2979). These include runoff from feedlots and land to which manure has been applied, spills from lagoons, and leaching from lagoons to groundwater. Rain events magnify the probability of CAFO waste reaching surface waters because they increase runoff from land to which wastes have been applied and the possibility of discharges from waste lagoons. Bacterial runoff to surface waters increases after rain events (Sobsey 2001; Mallin 2000) and can be positively correlated with the density of cattle on nearby land (Baxter-Potter and Gilliland 1988). As EPA discusses, some discharges from CAFOs are not the result of rain events, but rather are from other runoff and leaking lagoons (Preamble, section V, 66 Fed. Reg. 2979-2980).

A growing number of studies illustrate the ability of pathogens and antibiotics from CAFOs to contaminate surface and ground water. The Centers for Disease Control and Prevention (1998) found both antibiotics and pathogens in groundwater near hog waste lagoons and pathogens in nearby surface water. Chee-Sanford et al. (2001) detected antibiotic resistant bacteria in groundwater beneath two Illinois swine farms. Krapac et al. (1998) found E. Coli and fecal Streptococci in groundwater near Illinois hog lagoons. After a swine-manure lagoon ruptured in North Carolina, fecal coliform concentrations in surface waters were found to exceed 1x10⁶ cfu/100ml – 15,000 times the level considered safe for human contact by the state of North Carolina (Burkholder et al., 1997; Mallin, 2000). Similarly, after Hurricane Bonnie in 1998, North Carolina surface waters near CAFOs had fecal coliform concentrations 250 times greater than surface waters in a relatively pristine stream basin (Mallin 2000). Likewise, the Utah Department of Environmental Quality (1999) detected in Utah surface waters bacteria that appear to have originated from cattle feedlots.

Additional relevant data are available from several other ongoing studies. For example, USGS et al. (1999) detected antibiotics in 16 of 31 Iowa stream samples. Thurman and Hostetler (2000) detected antibiotics in ground water near waste lagoons. Preliminary results from an Arkansas investigation (Funkhouser et al., 1999) indicate that dairy farm runoff can contain a very high concentration of fecal coliforms. Isbister et al. (1999) found evidence that sediments from the Pocomoke River in Maryland contain antibiotic resistant bacteria, which apparently originated in runoff from fields to which chicken manure was applied.

At least two European studies have identified antibiotics used in animal agriculture in surface waters. Zuccato et al. (2000) detected tylosin and erythromycin, antibiotics used as livestock growth promoters in an Italian river. Alder et al. (2001) found sulfamethazine and other antibiotics used in veterinary medicine in surface water in Switzerland, and concluded that the source of the antibiotics was runoff containing manure, including land-applied manure.

Chee-Sanford et al. (2001) conducted a particularly important study in which they isolated antibiotic resistant genes in bacteria in waste lagoons and ground water near the lagoons. The concentration and diversity of the resistance genes formed a decreasing gradient from near the lagoons to 250 meters "downstream." The dominant fecal bacteria detected were Enterococci, although resistant soil-dwelling bacteria were also identified. These bacteria may have developed resistance through selective pressure while living in the livestock or the lagoons. Alternatively, they may have evolved in response to selective pressure from antibiotics that seeped directly into the soil from the lagoons.

The second scenario is reasonable given that substantial quantities of antibiotics are known to be excreted unaltered in waste, and to persist in the environment. Specifically, 25-75% of antibiotics administered to livestock are excreted (i.e., not metabolized) by the animals. Once excreted, antibiotics may remain viable for significant periods. Galvalchin and Katz (1994) determined that antibiotics can remain viable in soil for days to weeks and Zuccato et al. (2000) found that erythromycin and other commonly used antibiotics can persist in the environment for up to a year. Even antibiotics that degrade fairly rapidly are in effect persistent, because new quantities of antibiotics are continually released from CAFO wastes (Daughton, 1999).

In either case, the discovery of antibiotic resistant soil bacteria near a waste lagoon is significant because it demonstrates that soil bacteria can provide a reservoir of resistance genes arising from the use of antibiotics in agriculture. Even though soil bacteria are not usually pathogenic, such a gene reservoir is of concern because, as discussed later in these comments, bacteria can transfer resistance genes to unrelated bacterial species. The presence of a gene reservoir also makes it more likely that resistant bacteria will reach surface waters through runoff (Baxter-Potter and Gilliland 1988; Sobsey 2001).

The study by Chee-Sanford et al. also suggests other possible avenues of surface water contamination by resistant bacteria. For example, the identification of resistant bacteria in ground water 250 meters from a lagoon indicates that antibiotic resistant pathogens developed through animal husbandry may reach surface waters via ground water. Similar to the second scenario in Chee-Sanford's study, exposure to antibiotics from CAFO wastes that pollute rivers might lead waterborne bacteria to evolve resistance to these drugs.

The studies cited above demonstrate that wastes from intensive animal operations are polluting surface and ground waters with antibiotics and pathogens, including antibiotic resistant pathogens.

Waterborne pathogens have repeatedly caused outbreaks of infectious disease in the U.S. The Centers for Disease Control and Prevention (2000) provides information on over a dozen disease outbreaks that were attributed to either contaminated surface or ground water. The largest documented U.S. outbreak of a waterborne disease, in Milwaukee in 1993, was caused by contamination of drinking water from Lake Michigan with the protozoan Cryptosporidium, quite possibly from cattle manure (Mackenzie et al., 1994). Similarly, Gallaher et al. (1989) documented a waterborne Cryptosporidium outbreak in New Mexico, attributed to livestock waste. The New Mexico outbreak was due to both contaminated drinking water and recreational exposure to contaminated surface water.

Likewise, pathogens from animal waste recently caused the largest "multi-bacterial waterborne outbreak" in Canada’s history (Health Canada, 2000). E. coli and Campylobacter spp. from cow manure in runoff reached surface water with a direct hydrologic connection to groundwater that served two wells, which became contaminated (Health Canada, 2000; American Academy of Microbiology 2001).

These documented instances of waterborne disease outbreaks demonstrate that livestock feces can enter surface and ground waters and become a health threat to people who use these waters for drinking or recreation.

The recent report of the Interagency Task Force on Antimicrobial Resistance, in which EPA participated, makes clear that antibiotic resistance is an emerging public health crisis:

(Interagency Task Force, 2001 (emphasis added); see also Khachatourians 1998; Levy, 1998a).

Antibiotic resistant pathogens have already had measurable consequences in the United States in terms of increased medical costs and mortality rates for certain infectious diseases (Lieberman and Wootan, 1998; Khachatourians, 1998; Levy, 1998a).

Resistant bacteria arise primarily as a result of overuse of antibiotics in human medicine and animal husbandry (Levy, 1998b). Although medical overuse of antibiotics appears the primary cause of resistance in human pathogens, antibiotic overuse in livestock agriculture plays an important role. The best estimates now available indicate that 80% of the total amount of antibiotics used in the US are used in poultry, swine, and cattle production (Mellon et al., 2001). About 70% of the total is used nontherapeutically – not administered to sick animals to treat disease, but rather given to healthy animals, usually in their feed, to promote slightly faster growth and to prevent diseases otherwise likely under the crowded, stressful, unhygienic conditions at many CAFOs. The extensive use of antibiotics eliminates drug-susceptible microbes, allowing their resistant counterparts to thrive and dominate microbial communities (Salyers 1999; Khachatourians 1998; Levy 1998a). Nontherapeutic use of antibiotics – which involves long-term exposure to low doses – is particularly conducive to the creation and spread of resistant pathogens. A leading expert has noted that this practice constitutes "the perfect formula for selecting increasing numbers of resistant bacteria in the treated animals" (Levy, 1998a).

Moreover, all resistant bacteria - not just resistant pathogens - are of concern, in light of the demonstrated ability of bacteria to transfer genes to other, unrelated bacteria. Such gene transfer is frequent: "The exchange of genes is so pervasive that the entire bacterial world can be thought of as one huge multicellular organism in which the cells interchange their genes with ease" (Levy 1998a). As a result, resistant bacteria that arise at CAFOs have the potential to infect humans directly or pass on resistant genes to other bacteria that pose a threat to human health.

Recognition of the health threat from resistant bacteria prompted the European Union and countries such as Japan, Australia and New Zealand to ban in various degrees the nontherapeutic use of antibiotics in animal production. The American Medical Association (2001), American Public Health Association (1999), and other expert groups also oppose nontherapeutic use of medically important antibiotics in animal agriculture.

EPA has in theory long required zero discharge by many CAFOs - a requirement that, as EPA admits, has often been violated. EPA proposes new Best Management Practices, such as covering lagoons and nutrient management plans that the agency argues will now be the basis of the zero-discharge requirement for swine, veal, and poultry CAFOs, and a zero-discharge to groundwater requirement for beef and dairy CAFOs. These practices will not, however, come close to achieving zero discharge of pathogens and antibiotics.

EPA projects that its proposal would only result in a 50-60% reduction in pathogens (as indicated by presence of fecal coliforms and fecal Streptococci) (Preamble, Section VIII Fed. Reg. 3069). This reduction would occur even though there are no "explicit requirements or limits for pathogen controls" in the proposal (id.). Rather, EPA expects this reduction to occur as a result of the zero-discharge requirement on CAFO production areas, and implementation of nutrient plans for the land application of manure.

EPA makes no such projection for reduction in the discharge of antibiotics. Practices such as lining and covering lagoons would, by decreasing leaks and spills, decrease the discharge of antibiotic-laden CAFO wastes. However, antibiotics would likely remain active in CAFO wastes and could spread to surface water, in spills and leaks, or when wastes are land applied.

EPA should include the following two additional Best Management Practices in the agency's final regulations in order to prevent pathogens and antibiotics released from CAFOs (directly or via land-applied wastes) from polluting surface and ground water.

1. Pathogen Control: Require substantial reductions in pathogens as a Best Management Practice.
Assuming that EPA’s projections of a 50-60% reduction in pathogen discharge are correct (a questionable assumption), EPA's proposed Best Management Practices are still inadequate. Simply put, pathogen concentrations in CAFO wastes are too high for a reduction of 50-60% to be sufficient to protect human health. Rather, EPA must adopt a more aggressive approach to pathogen control, by requiring substantial pathogen reductions (e.g., above 99%). A variety of animal-management practices (e.g., improved husbandry and more thorough cleaning) as well as some technologies (e.g., certain digesters and some UV systems, see EPA 2001, Sobsy 2001) can be utilized for this purpose. These requirements should apply to any waste or waste-derived products that are applied to land.

2. Antibiotics: Adopt a Best Management Practice that bars land application of CAFO wastes and waste-derived products from animals that have routinely been fed antibiotics of current or potential medical importance.
EPA’s proposal currently fails to address the problem of antibiotics in animal wastes at all, a major deficiency. The final rule must include provisions that assure that CAFO wastes do not continue to contribute to the spread of antibiotic-resistance bacteria. Because of the difficulty of setting a numeric limitation for antibiotics, EPA should bar the land application of CAFO wastes from animals that received nontherapeutic antibiotics used in human medicine, closely related to antibiotics used in human medicine, or potentially useful in human medicine. (The same restriction should apply to products derived from CAFO wastes, unless it is demonstrated that the antibiotics are removed during processing.) Such antibiotics include bacitracin, chlortetracycline, erythromycin, lincomycin, oxytetracycline, penicillin, spectinomycin, sulfadimethoxine, sulfamethazine, sulfaquinoxaline, sulfathiazole, tylosin, and virginiamycin.

Nontherapeutic use of antibiotics in food-animal production is clearly unnecessary, as a ban on this practice was adopted in Sweden in 1986 and in Denmark between 1995 and 1999. In addition, the European Union banned several (though not all) nontherapeutic antibiotics by 1999. As noted by an expert from the Swedish Animal Health Service, "it is possible to reach good and competitive production results for rearing of poultry, calves, and pigs" without nontherapeutic antibiotics (Wierup, 1999). Likewise, a recent study on the Danish poultry industry concluded that terminating use of nontherapeutic antibiotics did not decrease productivity (Emborg et al., 2001). The authors noted that this positive outcome was "unexpected" by producers, who had anticipated economic losses due to lower productivity and increased mortality.

Moreover, projections of the economic consequences in the US of banning all nontherapeutic antibiotics indicate that costs would be minimal. The National Research Council (1999) estimates that the average annual per capita cost to consumers would be $4.84 to $9.72. Hayes et al. (1999) estimate an annual per capita cost of $2.75 for pork. These costs pale by comparison to the medical and human costs that an individual would face from a resistant infection.

Eliminating nontherapeutic use of antibiotics is clearly effective in reducing levels of antibiotic-resistant bacteria in animal waste, as demonstrated by a recent study in Denmark (Aarestrup et al., 2001). The study evaluated the occurrence of resistance genes for four antibiotics in approximately 2,600 isolates of Enterococcus faecium and Enterococcus faecalis collected from broilers and swine between 1995 and 2000; nontherapeutic use of the four antibiotics was terminated during that period. For each antimicrobial/bacterium combination save one, levels of resistance genes in the isolates dropped dramatically – by 50-70% for most combinations. The one exception was apparently due to continued use of a different antibiotic that co-selected for resistance; once the latter antibiotic was removed, resistance to the former dropped substantially.

VIII. Conclusion

Pathogens, including antibiotic resistant pathogens, and antibiotics spread to water in CAFO wastes are a serious human health threat. EPA's current CAFO proposal, if adopted, will fail to adequately address health threats from pathogens and antibiotics in CAFO wastes. To address this shortcoming, EPA should adopt Best Management Practices as specified above.

Respectfully submitted,

Karen Florini
Senior Attorney, Environmental Defense
1875 Connecticut Ave., NW Suite 1016
Washington, DC 20009
202/387-3500 x118

on behalf of

Environmental Defense
Physicians for Social Responsibility
Humane Society of the United States
Food Animal Concerns Trust
Institute for Agriculture and Trade Policy
Consumer Federation of America
Center for Science in the Public Interest

LITERATURE CITED

[Copies of all items cited are included in the Appendix to these comments]

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