by Shannon Piecuch

Raising food naturally is not a new concept. For years, farmers have been taking a stand against commercial food producers by refusing to use pesticides, chemical fertilizers, artificial growth hormones, and other conventional methods of raising crops and animals. All-natural and organic foods are promoted as being healthier than regular food, and are generally viewed as being environmentally-friendly. But sustainable farming is a step beyond simply not using chemicals in food production. In addition to producing food in a way that mimics nature, that is, without using lots of chemicals and artificial substances to increase production, this method of farming tries to create a system that is as self-sustaining as possible. In the 1990 Farm Bill, the official definition of sustainable agriculture used by the U.S. Department of Agriculture (USDA) is:

an integrated system of plant and animal production practices…that will, over the long term, satisfy human food and fiber needs, enhance environmental quality and the natural resource base upon which the agricultural economy depends, make the most efficient use of nonrenewable resources and on-farm resources and integrate where appropriate natural biological cycles and controls, sustain the economic viability of farm operations, and enhance the quality of life for farmers and society as a whole. (USDA, 2007)

In other words, sustainable agriculture takes into account the environment that produces the food and the society that eats the food, as well as actually producing the food.

It might be easiest to think of sustainable farming as it applies to growing crops, but it’s just as important to transfer these practices to raising livestock too. This means raising the animals solely on pasture instead of the conventional practice of sending them to feedlots before slaughter. Animals raised solely on pasture are termed ‘grass-fed’, as opposed to the ‘grain-fed’ animals on the feedlots that produce the majority of the meat that consumers buy.

The beef industry is a large factor in issues of feeding livestock grain versus feeding them grass, partly because beef operations are among the country’s largest livestock operations, and also because of the huge popularity of beef in this country. All cattle are initially raised on pasture, but almost all are sent to feedlots before slaughter, where they spend “100-200 days” (Umberger, Feuz, & Calkins, 2002, p 492) eating a high-energy, concentrated grain-based (usually corn) diet that rapidly puts on weight. This is called ‘finishing’, and it gets the cattle up to slaughter weight. The difference between grass-fed and grain-fed is that grass-fed cattle are never sent to a feedlot, but are instead finished on pasture on a grass-based diet. This might seem like simply a matter of preference, two different ways of doing things, but grass-fed beef has significant advantages over grain-fed beef. It has distinct health benefits, and the sustainable farming practices used to produce grass-fed beef are much better for the environment. It’s also much more economically feasible than might be assumed. For these reasons, the beef industry should shift towards using sustainable farming to maintain pastures and produce grass-fed beef instead of running feedlots and producing grain-fed beef.

The three main health advantages that grass-fed beef has over grain-fed beef are higher amounts of omega-3 fatty acids in relation to omega-6 fatty acids, a higher conjugated linoleic acid (CLA) content, and a much reduced risk of E. coli contamination. According to Leheska et al. (2008) in a study of the nutritional differences between grass-fed and grain-fed beef, omega-3 fatty acids “protect against coronary heart disease…and help lower blood pressure” (p. 3583), promoting overall heart health. In his book The Omnivore’s Dilemma, Michael Pollan (2006) states that omega-3 fatty acids have also recently been shown to play a role in the development and overall health of brain cells (p. 267). Omega-6 fatty acids, on the other hand, have been linked to increasing the risk of heart disease (Manning, 2009, p 49), essentially the opposite of omega-3 fatty acids. Leheska et al. (2008) briefly discuss the need for a balance between the two, as they both belong to the essential fatty acids group (p. 3583). As with cholesterol, some amount of omega-6 is necessary, but too much causes problems. Both Leheska et al. (2008) and Pollan (2006) mention the omega-6:omega-3 ratio as an easy way to examine the levels and balance of these two fatty acids (Leheska et al., 2008, p 3583), and that sometimes this ratio might be more important than the actual amounts of each fatty acid (Pollan, 2006, p 268). Grass-fed beef contains more omega-3 fatty acids and less omega-6 fatty acids (McCluskey et al., 2005, p 1), thus lowering the ratio from 10:1 or higher in grain-fed beef to around 2:1 (Pollan, 2006, p 269). CLA is a fatty acid that reduces the risk of heart disease (Manning, 2009, p 49). Recent studies have shown that it also has cancer-fighting properties (Long 2000). Grass-fed beef has much higher levels of CLA than grain-fed beef, which often contains no CLA at all (Long 2000). The significantly higher content of omega-3 and CLA makes grass-fed beef much more heart-healthy than grain-fed beef, and gives it the additional benefit of boosting the body’s defenses against cancer.

Pollan (2006) also describes cows as acting as a natural defense against E. coli infection in humans. The pH in a cow’s rumen, the part of their stomach that breaks down food, is neutral, so any E. coli bacteria present in their stomachs is adapted to that neutral pH. If humans ingest these E. coli, the acidity of our stomachs kills the bacteria. This only works, however, when the cows are fed grass. Feeding cattle only corn for any length of time increases the acidity of the rumen until it’s almost as acidic as human stomachs. Any E. coli bacteria that survive a corn-fed cow’s stomach are now acid-resistant, and will most likely survive the acid in our stomachs, going on to infect whoever ingests them. (Pollan, 2006, p 82). Breaking this natural defense mechanism means that while the contamination of beef with harmful E. coli bacteria can happen at any point along the production line of the beef, a major source is the cows themselves: because of their diets on the feedlot, harmful E. coli can already be in their guts, and if it makes it into the beef when the cattle are slaughtered, the contamination is in the meat from the beginning. Therefore, keeping cows on pasture and finishing them on grass instead of at feedlots eliminates a major source of E. coli bacteria contaminants.

The main environmental benefits of grass-fed beef come from converting cropland into permanent pasture. However, one of the first arguments against grazing large numbers of cattle is that they damage the land. In an article in Mother Earth News about converting cropland to pasture, Richard Manning (2009) stresses that overgrazing should not be confused with intensive grazing. Beef cattle consume massive amounts of corn; over half of the country’s grain crop is used to feed livestock. So, converting a large number of cattle from grain-fed to grass-fed necessitates converting cropland to pasture, otherwise farmers would quickly run out of land and the amount of excess corn would increase drastically, destroying the market. Overgrazing is a valid concern, but intensive grazing uses rotational grazing to divide the total pasture area into smaller segments, allowing each segment to recover after grazing before being used again. Grazing the land this way stimulates new grass growth, promotes biodiversity of plant species, and helps control weeds. (Manning, 2009, pp 50-51). This improves the quality of the grass, which in turn improves the quality of the beef.

Furthermore, the plains grasses that are native to most of the areas in the Midwest that now grow corn have deeper root systems than the row crops that replaced them (Manning, 2009, p 53). Repeatedly growing row crops year after year has depleted the topsoil of nutrients and organic matter. The soil of the grassland in the Midwest was originally around 10% organic matter, a percentage that has been cut in half over the last century (Manning, 2009, p 53). The grasses build a large root system to support the plant, and when cattle graze and eat the top part of the grass, there is no longer enough energy to support this root system, so it sheds the root system for a smaller one and grows back the larger roots as the plant grows back. The discarded root system adds to the organic matter in the soil and enriches it. (Manning, 2009, p 53). The deeper root system of grasses allows it to reach beyond the depleted topsoil so it can grow in the first place, then starts replenishing the organic matter and nutrients in the soil as the pasture is grazed, slowly increasing the quality of the soil. One critical advantage of better quality soil is the soil’s ability to absorb more water. Plowed fields can only absorb about 1.5 inches of rain per hour, whereas permanent pasture can absorb up to 7 inches of rain per hour (Manning, 2009, pp 52-53). Converting plowed fields to pasture would greatly reduce the risk of damaging floods in the Midwest.

Another important aspect of converting cropland to pasture is the potential to significantly decrease carbon emissions, and thereby to help reduce global warming. Carbon emissions are a big concern for agriculture: Pollan (2006) estimates that as much as one third of the greenhouse gases released into the atmosphere by human activity can be attributed to agriculture (p. 198). Manning (2009) explains how this happens by discussing the carbon cycle in pastures. The organic matter content of soil indicates its carbon content: the higher the organic matter content, the more carbon is in the soil. Tilling fields for planting adds oxygen to the soil, which decays organic matter in the soil and releases it as carbon dioxide. Annual crops such as corn do absorb large amounts of carbon dioxide, but they release most of it right back into the atmosphere when they’re harvested and the downed stalks decay. Permanent pasture, on the other hand, absorbs large amounts of carbon dioxide and keeps it because the plants aren’t harvested and cut every year. (Manning, 2009, p 53). By replenishing the soil’s organic matter, pasture grasses essentially pull carbon dioxide from the atmosphere and store it in the soil as carbon in organic matter. According to Pollan (2006), “if the sixteen million acres now being used to grow corn to feed cows in the United States became well-managed pasture [for those cows], that would remove fourteen billion pounds of carbon from the atmosphere each year, the equivalent of taking four million cars off the road” (p. 198). Also, the net release of carbon from croplands per year is about equal to the net storage of carbon in pasture per year (Manning 2009, p 54). Therefore, even turning some of the cropland into permanent pasture would make a huge dent in carbon emissions.

Converting cropland into pasture would also decrease fuel consumption. Raising cattle on grass uses less fossil fuel than the current feedlot system, and Pollan (2006) says that organic farming in general uses one third less fossil fuel than conventional methods (p. 183). He points out that when calculating the amount of fuel that beef productions use, the amount of fuel that goes into producing the corn used to feed the cows on the feedlot must also be considered. There’s the fuel used to make the pesticides and operate the machinery to grow, harvest, and process the corn; the natural gas used to make the chemical fertilizer; and the fuel used to transport everything. Adding these together equals about .25-.33 gallons of oil for each bushel of corn, or about 50 gallons per acre (Pollan, 2006, p 45). And that’s just the corn that the cows eat at the feedlot. On top of that is the fuel used to ship the cows from the farm to the feedlot, and the fuel used to operate all the machinery on the feedlot, such as the machines that mix the feed (Pollan, 2006, p 74), the machines involved in manure removal and management (Pollan, 2006, p 79), and the machines used to spray the pens with water to try to minimize the dust kicked up because there are so many cows on the feedlot (Pollan, 2006, p 80). Pollan (2006) estimates that between the fuel used to produce the corn the cow eats and the fuel used to manage the cow, sending one cow through the conventional feedlot system consumes the equivalent of 35 gallons of oil, which is almost a barrel of oil (p. 84). Judging by these numbers, it’s no surprise that the food industry as a whole consumes almost one fifth of all the petroleum used in the U.S., which is about the amount consumed by the automobile sector (Pollan, 2006, p 183). Grass-fed beef farms use a fraction of the fuel that grain-fed beef operations do, just by grazing the cattle and not feeding them any corn. In addition, they don’t need to use fertilizer or pesticides on the pastures, and the cows are only shipped to the slaughter house instead of from the farm to the feedlot and then from the feedlot to the slaughterhouse. Changing beef productions from grain-fed to grass-fed could be used as an important factor in reducing the nation’s fuel consumption.

With so much evidence proving the extensive benefits of grass-fed beef, one would expect that farms that raised grass-fed beef would be much more common, and grass-fed beef wouldn’t be viewed as a specialty food but as an important segment of the beef industry. But grass-fed beef faces two major obstacles: consumers accustomed to the taste of corn-fed beef and consumers who want extremely cheap and convenient food. In contrast to popular belief, converting to grass-fed beef is definitely economically feasible. According to Manning (2009), many farmers who raise grass-fed cattle can finish about two cows per acre of pasture, which is almost exactly the acreage needed to grow the corn that those cows would eat at a feedlot. Also, once the pasture is established, many farmers see a higher profit from the grass-fed cattle than they did when they were growing corn. One main reason is a drastic reduction in costs for machinery, fuel, fertilizer, and pesticides. The only problem is that it takes 1-2 years for the cropland to recover from intensive use for crops and develop grass sufficient to finish high-quality beef; before the land is fully recovered it can’t be grazed at full capacity. (Manning, 2009, p 51) This means the farmers need an alternative means of income until the pasture is ready. Government programs to supplement income might be the answer, but the government isn’t going to initiate these programs by themselves. The beef industry, with its industrialized farming practices, is very good at producing very cheap meat and making it very convenient. A push for anything different needs to come from the consumers.

Two studies, Sitz et al. (2005) and Umberger et al. (2002), examined American consumers’ willingness to pay premiums for the beef they preferred, comparing domestic grain-fed beef with imported grass-fed beef; Sitz et al. (2005) compared domestic grain-fed beef with imported grass-fed beef from Australia, and Umberger et al. (2002) compared domestic grain-fed beef with imported grass-fed beef from Argentina. About 60% of the consumers in each study preferred the domestic beef and were willing to pay up to $2.23 more per pound for it (Sitz et al., 2005, p 2867; Umberger et al., 2002, p 491). There was, however, a sizeable portion that preferred the grass-fed beef, about 20% of the consumers in each study, and they were willing to pay as much as $1.38 more per pound (Sitz et al., 2005, p 2867; Umberger et al., 2002, p 491). Both studies note that factors such as the amount of marbling (intramuscular fat) in the meat, varying aging periods, the genetics and/or breed of the cattle, and different feeding practices contribute to and affect the flavor of the beef (Sitz et al., 2005, p 2868; Umberger et al., 2002, p 492). Common U.S. practice is to feed cattle corn and age the meat for a relatively short amount of time, which contributes to the particular corn-fed taste of domestic beef (Umberger et al., 2002, p 492). Management or production practices that differ from this will produce meat that tastes different. Some of the differences in these practices result from the meat needing to be stored and shipped internationally; for example, the grass-fed beef from Australia was aged for approximately seven times as long as domestic meat is normally aged because it had to be shipped internationally and stored longer (Sitz et al., 2005, p 2867). Raising grass-fed beef domestically would eliminate many of these differences and make the flavor differences between grass-fed and grain-fed beef solely due to feeding practices.

According to Sitz et al. (2005), American consumers prefer corn-fed beef because “a steady supply of corn-fed beef is available to most consumers in the United States, [so] consumers have become accustomed to the flavor of corn-fed beef” (p. 2868). We’re willing to pay $2 more for beef that we think tastes better but we’re not willing to pay more for beef that is healthier for us, and on top of that is better for the environment? Granted, the environmental benefits are more abstract than the health benefits that we can relate directly to our personal lives, but with all the buzz these days about ‘going green’, the environmental benefits should be a rallying point as well. It all comes down to one thing at which our economy excels: choice. The options are presented, but we each individually still have to make the choice. Choose to know where the food comes from and what happens to it between there and the dinner table. Choose to spend a little more for food that is of better quality and doesn’t come with so many hidden costs. Choose to support local farmers who grow and raise food naturally and help them stand up to the big corporate farms that are preventing the current system from changing. Choose to have beef three days a week instead of four to offset the cost of paying more for grass-fed beef. We have done so many detrimental things to the land that we are so dependent on, we can certainly afford to make a small sacrifice to work towards repairing the damage. Saying that the consumers drive the market might be oversimplifying things, but a large part of our economy is based on giving the consumers what they want. If we the consumers say we want the healthier, more environmentally friendly, more naturally produced grass-fed beef, then something’s got to give.

References

Leheska, J. M., Shriver, B., Brooks, J. C., Miller, M. F., Hoover, L., Howe, J. C., et al. (2008). Effects of conventional and grass-feeding systems on the nutrient composition of beef. Journal of Animal Science, 86(12), 3575-3585. Retrieved from Agricola, IND44131411.

Long, C. (2000). Factory farming is fouling our food. Organic Gardening (1988), 47 (6), 12-13. Retrieved from Biological & Agricultural Index, BBAI00070417.

Manning, R. (2009). The amazing benefits of grass-fed meat. Mother Earth News, (233), 48-56. Retrieved from GreenFILE, 40221543.

McCluskey, J. J., Wahl, T. I., Li, Q., & Wandschneider, P. R. (2005). U.S. grass-fed beef: Marketing health benefits. Journal of Food Distribution Research, 36, 1-8. Retrieved from Agricola, IND43887360.

Pollan, Michael. (2006). The omnivore’s dilemma: A natural history of four meals. New York, NY: Penguin Books.

Sitz, B. M., Calkins, C. R., Feuz, D. M., Umberger, W. J., & Eskridge, K. M. (2005). Consumer sensory acceptance and value of domestic, Canadian, and Australian grass-fed beef steaks. Journal of Animal Science, 83, 2863-2868. Retrieved from Agricola, IND43759770.

Umberger, W. J., Feuz, D. M., & Calkins, C. R. (2002). U.S. consumer preference and willingness-to-pay for domestic corn-fed beef versus international grass-fed beef measured through an experimental auction. Agribusiness, 18(4), 491-504. Retrieved from Biological & Agricultural Index, BBAI02113905.

USDA, Alternative Farming Systems Information Center. (updated August 2007). Sustainable agriculture: Definitions and terms. [Ed. Mary V. Gold]. National Agricultural Library Cataloging Record. Retrieved from www.nal.usda.gov

by Corey Lynch & Kathryn Liddell

In 2007 the U.S. Environmental Protection Agency estimated that “294,000 sites will need to be cleaned up over the next 30 years. This includes 77,000 known sites and an estimated 217,000 sites yet to be discovered. Total clean-up costs are estimated to be $209 billion” (Coker, 2007, p. 28). With a task of this scale, efficient and cost-effective soil remediation techniques are essential. Implementing these remediation techniques involves thorough research of the contaminated site’s characteristics and the remediation technique’s abilities, advantages, and disadvantages. For soil remediation technologies to be most effective and applicable, biological, chemical and physical remediation technologies must be combined based upon contaminated sites’ characteristics.

Bioremediation Techniques

In the past, the only option for the remediation of toxic chemicals was the incineration of the contaminated areas. Today, more responsible techniques, such as bioremediation, are being employed. Bioremediation is the use of biological agents, such as bacterium or plants, to convert dangerous organic compounds into more stable carbon dioxide, methane, water or inorganic salts. As stated by the EPA in the Superfund annual report in 2001 “[b]ioremediation is being used with increasing frequency to remediate contaminated media at hazardous waste sites…” (Environmental Protection Agency, 2001, p. 1).

Brian Timmins, director of Environmental Technologies, states that, “…if it is soluble, it is likely biodegradable and it is just a function of establishing the right microbial conditions” (Personal Communication, 2009). To create these conditions, you can either follow the in situ, above ground, or the ex situ, underground, techniques. In situ techniques are utilized on site, and are far less costly to conduct. This approach involves five steps. First is bio-venting, when contaminated unsaturated soils are aerated as to stimulate biodegradation. Second is the slurry lagoon aeration phase, in which contaminated soils come into contact with natural air in a lagoon to promote biological degradation. Next is biosparging, in which forced air is added to a ground water system to improve biodegradation and volatilization of contaminants. The final phase occurs under both aerobic and anaerobic conditions to complete the breakdown of the contaminant.

Unlike in situ techniques, ex situ methods can be conducted off site, but can be far more costly, not only in dollars and cents but in risk of further site contamination. Because of the great risk, the ex situ method is still often conducted on site. The ex situ method is done in four phases. The first phase is general land treatment, in which the first excavation of contaminated soils happens. The contaminated soil is removed and deposited in lined beds and periodically turned over to ensure aeration. The next phase is composting, in which the contaminated soils are mixed with “bulking agents” to add surface area to the mixture. Next is the bio-pile phase, in which the bulked soil is placed in above ground enclosures. The last phase is the slurry-phase treatment. According to the EPA in 2001, “[a]n aqueous slurry is created by combining soil, sediment, or sludge with water and other additives. The slurry is mixed to keep solids suspended and microorganisms in contact with the contaminants. Treatment [of the contaminants] usually occurs in a series of tanks” (Environmental Protection Agency, 2001, p. 4).

Chemical and Physical Remediation Techniques

Other remediation technologies include chemical remediation and physical processes, which, among numerous options, can also be divided into in situ and ex situ techniques. In situ is performed at the contamination site, minimizing the exposure pathways. Ex situ techniques involve the removal of contaminated soil. The soil is either treated on-site or moved to another location for treatment (Sparks, 2003).

In situ techniques include volatilization and isolation and containment. Volatilization is based upon air venting through the soil by injecting or inducing a draft fan in the soil. This results in airflow through the soil. Soil particle movement is restricted but air movement can freely occur. The volatilized contaminant is then recovered using treatments such as activated carbon. Volatilization is limited to volatile organic compounds, but is relatively low-cost (Sparks, 2003). When considering volatilization it is important to note that “[volatilization] of hazardous chemicals is both a public health and air quality concern” (Coker, 2007, p. 29). In isolation and containment, subsurface physical barriers are installed to minimize lateral migration of contaminates. These barriers can be things such as clay liners and slurry walls (Sparks, 2003). The addition of surfactants to clay minerals is another method of minimizing contaminant movement. Surfactants can enhance the retention of organic pollutants, further minimizing the mobility of pollutants (Sparks, 2003).

Ex situ techniques include solidification/stabilization, excavation, and chemical extraction. In solidification/stabilization, an additive is added to the removed contaminated soil, encapsulating the contaminants. The soil mixture is then landfilled so the contaminants cannot move freely (Sparks, 2003). The accepting landfills are usually lined to minimize the mobility of the contaminants and are located in a region of low soil permeability. Excavation and disposal costs are high, and can include long-term liability (Sparks, 2003).

Remediation of soils contaminated with heavy metals can be expensive therefore the immobilization of a heavy metal can be a cost-effective solution (Alpaslan & Yukselen, 2001). A study by Alpaslan and Yukselen (2001) showed that lime and cement are effective in lead immobilization, while activated carbon and clay are not very efficient in lead immobilization. Determining the best chemical additive for the contaminant(s) present is important in developing an efficient remediation plan. In the chemical extraction technique, “the soil is mixed with a solvent, surfactant, or solvent/surfactant mixture to remove the contaminants” (Sparks, 2003, p.28). Lead, “the most frequently found metal at U.S. hazardous waste sites,” can be extracted using Water-Soluble polymers (WSP) (Sauer, Ehler, & Duran, 2004, p.585). When lead is bound to the WSP it can easily be concentrated by ultrafiltration to allow for the recycling of the extraction agent and the disposal of lead (Sauer, et al. 2004). In a study by Sauer, Ehler, and Duran (2004), WSP removed more than 97% of lead from contaminated Superfund soil samples. As this study demonstrates, chemical extraction can be an effective technique for the remediation of soils contaminated with heavy metals.

Other newly developed chemical and physical remediation technologies have only been proven on a laboratory scale. Ultrasound remediation has shown to be successful on a laboratory scale, but applying ultrasound in industry requires considering the costs of larger scale application (Shrestha, Duong, & Sillanpaa, 2009). In a study by Shreshtha, Pham, and Sillanpaa (2009) ultrasonication was shown to reduce concentrations of persistent organic pollutants (POPs) such as hexachlorobenzene (HCB) and phenanthrene (PHE). High-frequency ultrasound has also been shown to effectively remove DDT from sand slurries (Thangavadivel, et al., 2009). Intensity limitations in currently available equipment and low volume coverage make the practicality and affordable application of high-frequency ultrasonication currently only possible in laboratory settings (Thangavadivel, et al., 2009).

Superfund Overview

In the 1970s there were many abandoned toxic sites scattered across the country with no one organization, governmental or private, willing to take charge of the cleanup actions. In the late seventies to early eighties, Congress passed the Comprehensive Environmental Response, Compensation and Liability Act (also known as Superfund) in the wake of the discovery of many of the toxic sites, and the EPA began organizing the cleanup of 114 of the worst sites across the country. Superfund sites range from national disaster areas such as Love Canal in Niagara, New York, to smaller, yet equally important sites such as the Buzzards Bay PCB cleanup and the Hatheway & Patterson site, located in Mansfield Massachusetts, which is a 56 year old time capsule of largely unknown contamination. The EPA, with Superfund as its back, now has the power necessary to “compel responsible parties to perform cleanups or reimburse the government for… [these] cleanups” (Environmental Protection Agency, 2009, p. 1).

Combining Remediation Techniques for More Effective Results

Understanding the biological, chemical and physical remediation techniques discussed above is important in determining the most effective remediation plan for a contaminated site. As stated by Mark Brusseau, a Professor at the University of Arizona in the Department of Soil, Water and Environmental Science, in 2009, “[e]ach technology is suitable for only a subset of site types…[the] most effective [technologies] are very site specific depending on the nature of the site and the remediation objectives. … [N]o single technology will be the perfect solution. At most sites, multiple technologies are used, either simultaneously or sequentially” (personal communication). The combination of remediation techniques is exemplified in the Superfund site Hatheway & Patterson, in Mansfield, Massachusetts. Hatheway and Patterson Company is a former wood preserving facility comprising approximately 40 acres. It is bordered by residential properties, forested and wetland areas, and a welding and masonry supply company. Releases of chemical compounds have impacted fisheries and wetlands and threaten ground water of municipal and private drinking water wells (Environmental Protection Agency, 2009). Hazardous compounds located at the site include dioxins, furans, arsenic, chromium, copper, PCP and PAHs (Environmental Protection Agency, 2009). The Record of Decision, signed in 2005, states that remediation components will include excavation, stabilization/solidification, and off-site disposal of soils contaminated with dioxin and oily material (Environmental Protection Agency, 2009). Clean backfill will replace the excavated soil. The excavated soils containing PCP, semi-volatile organic compounds, and arsenic will be tested for leachability then stabilization/solidification agents will be used to immobilize pollutants. The treated soil will then be disposed of on-site under a low-permeability cover (Environmental Protection Agency, 2009). The remediation approach to this site includes excavation, stabilization/solidification, containment, and off-site landfill disposal. These techniques are used for particular contaminates within the site, and combined to create the most effective clean-up of the contaminated site. “Several factors are considered when deciding which technology to use at a particular site. An initial critical factor is the feasibility of a particular technology for that specific situation. … then several other factors are part of the evaluation – cost, long-term effectiveness, regulatory, and public acceptance” (Mark Brusseau, personal communication, November 13, 2009). Approaching site remediation with collective techniques can be more effective in extensive site remediation than the use of a single technique.

Unlike the Hatheway & Patterson Superfund site, the Buzzards Bay clean up could have employed more responsible techniques. Before being banned by the EPA in 1979, polychlorinated biphenyls, or PCBs, along with hundreds of other industrial and municipal wastes, were dumped directly into the Acushuet River and deposited in the bay. Today the sediment beneath Buzzards Bay is contaminated with layers of industrial waste and PCBs. PCBs were known to be above allowable concentrations all through the 1970s, and in 1979, the same year the bay was closed to commercial and recreational fishing and lobstering, they were found in concentrations “high as 100,000 ppm” (Environmental Protection Agency, 2001, p. 1) (the maximum allowable concentration is 50 ppm). Instead of applying the more widely accepted chemical, physical, or bio remediation techniques, the established group simply dredged the bay, and incinerating the contaminants. Instead of incinerating the PCBs, which reintroduces them into the environment in a different form, ex-situ remediation could have been performed.

Examination of remediation techniques reveals the wide availability of biological, chemical, and physical technologies that may be utilized to create an efficient clean-up process. The Hatheway & Patterson Superfund site is an example of combining techniques for responsible cleanup, while sites such as Buzzards Bay exemplify weak remediation strategies. “The innovation… to interconnect physical, chemical, and … biological technologies into a unified site-specific, coordinated system” (p. 36) avoids the “standard industry practices” (p. 36) in which “these technologies would normally have been deployed as standalone systems and prone to significant deficiencies or failure” (Vigneri, Adams, Scrudato, 2007, p. 36). The remediation challenges facing Americans require the re-evaluation of available remediation technologies in order to create the most efficient, cost-effective plan for each contaminated site.

References

Alpaslan, B. & Yukselen, M.A. (2002) Remediation of lead contaminated soils by stabilization/solidification. Water, Air, and Soil Pollution, 133(1-4), 253-263. doi: 10.1023/A:1012977829536

Buzzards Bay National Estuary Program (1992) Comprehensive Conservation and Management Plan the 1991 CCMP (8/91 version approved by EPA in 1992) (Chapt. 6)

Coker, C. (2007). Clean-up methods without chemicals. In Business, 29(1), 28-29. Retrieved from ebscohost.com

Sauer, N.N., Ehler, D.S., & Duran, B.L. (2004). Lead extraction from contaminated soil using water-soluble polymers. Journal of Environmental Engineering, 130(5), 585-588. doi:10.1061/(ASCE)0733-9372(2004)130:5(585)

Shrestha, R. A., Pham, T. D., & Sillanpää, M. (2009). Effect of ultrasound on removal of persistent organic pollutants (POPs) from different types of soils. Journal of Hazardous Materials, 170(2), 871-875. doi:10.1016/j.jhazmat.2009.05.048

Sparks, D.L (2003). Environmental Soil Chemistry, 2^nd ed. Boston: Academic Press.

Thangavadivel, K. et al. (2009). Application of high frequency ultrasound in the destruction of DDT in contaminated sand and water. Journal of Hazardous Materials, 168(2-3), 1380-1386. doi:10.1016/j.jhazmat.2009.03.024

U.S. Environmental Protection Agency. (October 2009). Waste Site Cleanup & Reuse in New England: Hatheway & Patterson. Retrieved from epa.gov

U.S. Environmental Protection Agency. (September 2001) Use of Bioremediation at Superfund Sites. Retrieved from epa.gov

Vigneri, M., Adams, R., & Scrudato, R. (2007). Remediation for those hard-to-reach places. Pollution Engineering, 39(6), 36-40.

by Jacob Hiller & Amy Gifford

Introduction

Milo Vaccaro is an 11-year old boy with autism who frequently had severe outbursts in public and often tried to run away from his parents. It was only a matter of time before his family realized that they could not deal with his disability on their own. A few weeks later Chad, an autism service dog, walked through the door. The relationship between Milo and Chad developed rapidly, and soon Milo’s mother noticed significant positive changes in her son’s ability to communicate and be comfortable in social or public situations. Milo has progressed so well that the Vaccaros are thinking about lowering his medication (Baranauckas, 2009). This is just one of many recent examples demonstrating the mental and physical benefits of animal-assisted therapy in treating children with diseases and disabilities.

Pets are so often integrated into the American lifestyle that we tend to overlook the benefits that our interactions with them may have on our emotional well being. However, when suddenly deprived of our pets, for instance when taking a vacation, going to college, or staying in a hospital, we notice their absence considerably. In the latter situation, mental health can drastically decrease due to stress, fear, pain, and loneliness, which in turn can directly affect physical health. Interactions with animals can benefit a patient’s mental state by alleviating some of the emotional strain that comes from being sick.

Animal-assisted therapy (AAT) is now used throughout the country in nursing homes for elders with dementia or in pediatric hospitals for children with acute illnesses. It is used in physical rehabilitation facilities where patients with physical debilitations interact with animals on an active level such as riding a horse and in community centers where teenagers with learning and behavioral disabilities learn to care for animals. Some of the most positive results have come from animal therapy with children.

History

In their article “Pet Therapy Research,” therapy nurses Hooker, Freeman, and Stewart (2002) state that the first known account of animal assisted therapy was in England in 1792, where the belief promoted by an asylum-like facility, the York retreat, was that the use of birds and rabbits in the treatment of mentally ill patients was better than then-current treatment techniques, which according to Wikipedia were painful blistering, whipping, and long-term restraint (Hooker et al., 2002). Hooker et al. (2002) state that the systematic study of animal assisted therapy, with recorded observations, did not begin until the 1960s. Dr. Boris Levinson, a child psychologist, concluded that, “the use of a dog in psychiatric care was determined to be a positive focus in beginning communication, allowing defenses to soften, building a rapport, and initiating therapy” (p. 18). An explosion in animal assisted therapy research followed Dr. Levinson’s findings.

Current Examples

Many studies have been done looking at the effects of AAT on children with diagnosed mental disorders, hypothesizing that the animal interactions would improve social and behavioral functioning. In their article, “Animal-assisted Therapy for Children with Pervasive Developmental Disorders” Martin and Farnum (2002) conducted an experiment involving AAT with children diagnosed with “pervasive developmental disorder (PPD), disorders characterized by a severe impairment of social functioning and interactions…” (p. 657). This included children with diagnoses of autism and Asperger’s. Children with PPD are often unable to form relationships because they are socially withdrawn and disconnected. This study was conducted in the belief that animals can provide a stepping stone of sorts for children with social disabilities, allowing the children to form relationships with the animals first and then be able to expand their boundaries and form relationships with other humans (Martin & Farnum, 2002).

The experiment consisted of therapeutic sessions with a ball, a stuffed dog, and a live dog. The children with PPD were evaluated based on seven guidelines designed by Martin and Farnum (2002) “including imitation, perception, fine motor control, gross motor control, eye-hand coordination, cognitive performance, and cognitive verbal performance” (pp. 661). Their results provided insight that the AAT had beneficial effects on the children with PPD by overall increasing the children’s energy. This was expressed through play with the animal. The children also exhibited focused attention on the animal and were less easily distracted, something that is difficult for children with PPD. The most important evidence that AAT could help children with these diagnoses was that the children were subsequently able to stay on topic with the therapist as opposed to talking about unrelated subjects in response to questions due to an inability to communicate and interact. This result showed a direct improvement of the children’s social disorders. When the children were placed with the ball and stuffed dog the opposite result occurred. In therapy sessions the children were unfocused, unresponsive, and off-topic.

Animal-assisted therapy has also had other positive outcomes among children with behavioral conditions stemming not from a disorder but from abuse and/or neglect. In her article “Animal-assisted Therapy with Children Suffering from Insecure Attachment Due to Abuse and Neglect…” Parish-Plass (2008) discusses her experimental results implementing AAT with children removed from severely abusive and neglectful homes. Parish-Plass (2008) dictates that children who come from these types of home-lives have distrustful behaviors, especially around adults, and, as a result, are particularly hard to connect with in therapeutic sessions. Abused and neglected children also have a hard time behaving as normal children in the sense of playing pretend or using imagination, which is a tactic used by many therapists, as Parish-Plass (2008) explains, to “reach the inner world of the child” (pp. 8). In her experiment Parish-Plass (2008) used AAT with multiple children and carefully observed their resulting behaviors and the overall effects of this specific therapy. Parish-Plass (2008) concluded that AAT was effective with “children suffering from insecure attachment and the affects of trauma [from abuse and neglect]” (p. 27) because it could blend the line “between reality and play…. [and t]he child may take advantage of either play or reality, or combine the two” (p. 27). She also made several determinations as to why AAT was so effective among children from abusive backgrounds. Animal-assisted therapy requires children to form an immediate emotional connection with the animal, which in turn drives them to develop a relationship with the therapist who already has a relationship with the animal. This relationship also helps to raise the child’s self esteem and their feelings of competence and comfort because the animal has accepted them. On a more physical level, previous studies have proved that interactions with animals can reduce blood pressure and heart rate, which decreases stress and anxiety and leads to a feeling of ease. Among children who have spent their lives building defenses when in uncomfortable settings, their comfort is key to their emotional health and AAT provides a setting were this can occur. All in all, Parish-Plass made conclusion that the use of AAT with children from abusive and neglectful homes can be beneficial, which is extremely important since numerous studies have shown that abused children later become abusive parents. Animal-assisted therapy may be able help stop this pattern of violence.

Another important usage of animal-assisted therapy is for the management of pain in pediatric care settings. In the article “Animal-assisted Therapy As a Pain Relief Intervention for Children,” Braun, Stangler, Narveson, and Pettingell (2009) argue that their experiment proves that AAT can have notable effects alleviating pain in children with acute diseases. Their experiment was based off measured “pain scores” that were calculated from vital signs taken before and after children received animal therapy. These “pain scores” were then compared to scores taken from children who received no therapy. The results from Braun et al. (2009) showed that while certain vital signs seemed not to vary between the two groups there was a significant decrease in overall “pain scores” for the experimental group. This means the children receiving AAT had a significantly larger decrease in pain than the children who received no AAT. Braun et al. (2009) discussed the current reasoning behind the positive effects of animal-assisted therapy and pain level. A child interacting with an animal undergoes an emotional response which, as Braun et al. (2009) point out, in turn stimulates “the release of endorphins, which induce a feeling of well-being, and lymphocytes, which increase the immune response” (p. 107). These chemical releases in the body are directly connected to physical responses such as beneficial changes in heart rate, blood pressure, respiration rates, and temperature. These current beliefs are supported through the experiments done by Braun et al. (2009). They are important potential future uses of animal-assisted therapy with children diagnosed with both acute and chronic diseases that involve high levels of pain and stress.

Awareness of Anxiety and Training Solutions

All of these experiments have shown that AAT has beneficial physiological effects on children because their mental and emotional states improve through interactions with animals. However, there is also a possibility that AAT could sometimes have a negative emotional effect on the children the therapists are trying to help. For example, if a dog were to enter a hospital there would presumably be many children thrilled to see and to lay a hand on the dog. On the contrary, there may be children who are scared of dogs. This may be due to traumatic experiences with dogs, such as getting bitten, or because of never having been around an animal before. This may cause children to become nervous, causing an increased heart rate and blood pressure, and in turn having negative consequences such as anxiety. But, with the proper training, therapists can minimize this problem.

Maureen and Gary Ross established a company known as “Therapet” in an attempt to establish “standards of practice for use of specially trained animals in the healthcare setting” (Therapet 2009). The Therapet website (2009) suggests that any animal to be used in AAT should be a domesticated animal and should be able to complete a comprehensive certification program. The first step of their program is to go through a very intense obedience training. Therapet (2009) suggest that the owner and the animal “attend a beginner, intermediate and advanced level class before testing. Each of these levels are usually offered in 6-8 week sessions” (para. 3). In order for the animal to become “Therapet” certified, they must also pass a Canine Good Citizens Test, which Therapet (2009) explains, is a test that “evaluates the dog to see if they have basic obedience skills” (ll. 10-11). The second step of the intensive program is the skills class, a five-week long class in which, Therapet (2009) explains, the “[p]articipants learn all the special commands needed to work in a hospital environment and practice around all the equipment including hospital beds, walkers, crutches, canes and therapy tables” (para. 4). Before the final step can be completed the animals must be thoroughly examined by a veterinarian. Upon completion of the examination, the animal and owner may move on the final step, the Temperament Test. Therapet (2009) states that, “animals may only be tested twice…. [i]f the dog passes, then it is able to begin a probationary period volunteering with supervision” (para. 5). Through their training, the pets become much like nurses, caring and bringing a smile to each patient they come in contact with.

Conclusion

Animal-assisted therapy is currently integrated into numerous rehabilitation, therapeutic, and medical facilities for all types of patients, old and young, suffering from mentally and physically debilitating diseases. One particular area of AAT effectiveness is with children. Even though a great deal of research continues to be done on this type of therapy, the AAT programs throughout the country, such as the Canine for Kids program at the Schneider Children’s Hospital (Byalick, 1999) have realized that animals have a marked beneficial effect on children. In a hospital setting, children can easily become depressed or anxious especially if they don’t fully understand what is going on and often visitation from a pet is the only effective way to improve their mental state. In her New York Times article Byalick (1999) states that according to Dr. Bob Gluck, a man closely affiliated with Canines for Kids, “[t]hese dogs have a kind of primitive attraction for a lot of kids. Those who don’t respond to clowns and athletes light up when the dogs arrive” (Byalick, 1999). Children’s mental state is closely connected with their physical health and even if AAT can only provide simple companionship, it is often a significant improvement. Emily Grankowski, in charge of the pet therapy program at the Children’s Hospital of Orange County, is quoted in Baranaucka’s article, “Exploring the Health Benefits of Pets” (2009) on her personal experiences with sick children and animal-assisted therapy. She says that “some patients who have refused to speak will talk to the dogs and others who have refused to move often reach for the dogs so they can pet them” (p. 2). Children are extremely resilient both mentally and physically. However sometimes it takes that unexplainable bond between humans and animals to help them overcome their mental or physical pain.

References

Baranauckas, C. (2009, October 6). Exploring the health benefits of pets. The New York Times. Retrieved from nytimes.com

Braun, C., Stangler, T., Narveson, & J., Pettingell, S. (2009). Animal-assisted therapy as a pain relief intervention for children. Complementary Therapies in Clinical Practice, 15, 105-109. doi: 10.1016/j.ctcp.2009.02.0008

Byalick, M. (2009, April 18). When command is ‘heal,’ these dogs obey. The New York Times. Retrieved from nytimes.com

Heimlich, K. (Oct-Dec 2001). Animal-assisted therapy and the severely disabled child: a quantitative study. Journal of Rehabilitation, 67, 48-54. Retrieved from web.ebscohost.com

Hooker, S. Freeman, L. & Stewart, P. (2002). Pet therapy research: a historical review. Holistic Nursing Practice, 17, 17-23. Retrieved from ncbi.nlm.nih.gov, PMID: 12465214

Martin, F. & Farnum, J. (2002). Animal-assisted therapy for children with pervasive developmental disorders. Western Journal of Nursing Research, 24, 657-670. doi: 10.1177/019394502320555403

Parish-Plass, N. (2008). Animal-assisted therapy with children suffering from insecure attachment due to abuse and neglect: a method to lower the risk of intergenerational transmission of abuse? Clinical Child Psychology and Psychiatry, 13, 7-30. doi: 10.1177/1359194507086338.

Therapet Foundation (2009). Therapet Animal Assisted Therapy. [Ross, G. and Ross, M., co-founders] Retrieved from www.therapet.com

by Niina Heikkinen

As the H1N1 virus continues to spread around the globe, the importance of understanding zoonoses—pathogens that can be transmitted from one species to another—becomes increasingly clear. Not only do zoonoses account for 60 percent of emerging diseases, in the past quarter century about 75 percent of ‘new’ human diseases have come from animal populations (Tomley & Shirley, 2009). Although wildlife has been increasingly identified as playing an important role in zoonotic disease transmission, for the most part, responses to zoonosis transmission from animal to human populations has focused on risks associated with working with livestock and companion animals. In order to be able to effectively halt the spread of zoonoses, much greater emphasis must be placed on understanding and preventing the causes of disease transmission in wildlife populations.

Identifying Causes of Zoonotic Transmission

One of the first steps to tackling zoonotic disease transmission is identifying how zoonoses enter human populations from wildlife species. Many researchers in the field of infectious disease attribute the recent increased incidence of zoonotic disease transmission to rising urbanization, destruction of wildlife habitat, globalized trade, and the increased migration of humans and animals (Cabello & Cabello, 2008, abstract). A number of researchers have found that global warming increases the incidence of zoonotic disease transmission. Milder temperatures allow temperature-sensitive viruses and bacteria to live longer, increasing their capacity to infect wildlife. Animals and disease-carrying insects are able to travel greater distances, introducing new diseases to different geographic regions. Meanwhile, a more temperate climate has led to greater population density, and as a result, more disease transmission, (Parkinson & Butler, 2005 abstract). Also, both subsistence and highly industrialized animal management practices as well as lack of strict health standards during wildlife importation play a potentially significant role in increasing the risk of disease transmission from wildlife (Tomley & Shirley, 2009) (Pavlin et al. 2005). The wide range of factors contributing to the spread of zoonotic disease illustrates the complex global health issue facing the international health care community. Recent research in zoonosis transmission highlights the need for collaboration between agencies not directly involved in human and animal health, such as urban development groups and environmentalists.

Despite growing evidence that wildlife play a key role in zoonotic disease transmission, there is almost no scientific literature about how diseases are transmitted within wildlife populations. Even though some species such as birds, bats and small mammals have been identified as common initial or reservoir hosts of virulent zoonoses like avian influenza, rabies and plague, little is known about how diseases are transferred within these species. Zoonotic diseases in large mammals and primates can serve as a particular risk to human populations as these species often serve as a food source in developing nations, yet disease transmission is not well understood in these species either (“Survey Wild Animals,” 2009). Therefore, another key component in preventing the spread of zoonoses would be to increase funding for research on how diseases are transmitted in these species.

Part of the reason for this lack of research in wildlife may be because in the short term, addressing human outbreaks alone has often worked to control the spread of disease in human populations. Human vaccination, anti-viral and antibacterial treatments, as well as international reporting of confirmed cases of zoonoses have proven to be mostly effective in slowing the global spread of some zoonoses. (Childs & Gordon, 2009, pp. 422-423). Thus there may seem to be little motivation for international governments to invest millions of dollars in additional research projects.

However, reactive treatment to outbreaks in the human population does nothing to prevent future outbreaks of viruses that may undergo further mutation, nor does it prevent the introduction of completely new zoonoses into the human population. Dr. Nathan Wolfe, Director of the Global Viral Forecasting Initiative and known for discovering that retroviruses can spread from nonhuman primates to humans, argued in a TED conference that the global health community can no longer afford to ignore the mechanisms for cross-species disease transmission.

To illustrate his point, Wolfe discussed the origins of HIV, one of the world’s most deadly viruses, which first infected chimpanzees in the Congo. Wolfe said his research has revealed that the virus had likely infected thousands of people who hunted chimpanzees for meat in Brazzaville, Congo as early as 1929. Wolfe pointed out that had the international community discovered HIV when it had first infected humans, the current AIDS pandemic might have taken a much different and less virulent turn (“Nathan Wolfe’s Jungle…” 2009). With the rapidly growing global human population reaching approximately 6.5 billion in 2008, the percentage of cross-species disease infection is only likely to increase as humans have even greater contact with wildlife through expansion of urban areas and destruction of wildlife habitats (Tomley & Shirley, 2009).

Finding A Solution

To gain a better understanding of the transmission of zoonotic diseases in wildlife, researchers must identify high-risk areas where zoonotic disease transmission is most prevalent and then establish systematic methods for tracking the spread of disease in these areas. Early detection of virulent zoonotic disease, coupled with increased research on effective treatment methods for wildlife will greatly reduce the likelihood of new global pandemics. While researchers differ on the methods that should be employed to track these diseases, all agree that establishing more effective disease surveillance methods is essential for protecting animal and human health. One of the main concerns with establishing national and international wildlife surveillance is that since there are few organizations to build from, most projects must be established from scratch, at very high cost. In order to make costs less prohibitive, some researchers suggest limiting surveillance efforts to diseases that pose clear pandemic threats, such as H1N1. Few nationwide wildlife population estimates exist, therefore the use of target studies in combination with statistical modeling and geographical information system technology could be used in order to create maps of high-risk areas (Childs & Gordon, 2009, p. 423).

A second major challenge in controlling zoonotic disease is determining how to manage infected wildlife populations. Traditionally, infected wildlife have been subject to culling through shooting, trapping, poisoning or use of pathogenic agents (Cooper & Larsen, 2006). Such methods often involve the culling of animals that are healthy but at risk for catching the disease. Action of this kind has raised the ire of animal welfare groups. These groups demand more humane methods of population control such as vaccination and immunocontraception. Other researchers maintain that the use of immunocontraception, which creates immune resistance to the body’s own gametes, is too ineffective. Not only must every animal in the population be caught and injected individually with the vaccine, some species have been shown to be resistant to it, and most require one or more booster shots in order for the vaccine to remain effective. Critics fear that species that have natural resistance to the contraception vaccine will create inbred populations that will be exceptionally susceptible to zoonotic disease because of their lack of genetic diversity (Cooper & Larsen, 2006, p. 822). Therefore, while humane, immunocontraception seems to be am impractical solution to halting zoonosis transmission. However more research needs to be done on finding effective ways to either vaccinate or treat wildlife for zoonotic disease.

International Collaboration

In order to increase the effectiveness of cross-species disease transmission control, organizations involved in national and international health of human and animal species must increase their collaboration so that the can respond more swiftly and accurately in cases of potential zoonotic disease pandemics. One of the only models in national health for this kind of collaboration is evident is the surveillance of rabies. All hospitals, veterinary clinics and wildlife organizations in the U.S. have a national mandate to report confirmed cases of rabies to the Centers of Disease Control and Prevention. Unfortunately, rabies is the exception to the rule. It is the only disease about which the Centers of Disease Control and Prevention have gathered extensive data concerning animal as well as human transmission (Childs & Gordon 2009, p. 422). Increased collaboration between federal agencies like the Centers of Disease Control and Prevention, U.S. Department of Agriculture, U.S. Department for International Development, U.S. Department of Defense, the World Heath Organization, USAID, and private organizations such as the Wildlife Conservation Society and Wildlife Trust is necessary for fully understanding and preventing the spread zoonotic disease.

The Global Viral Monitoring Initiative, lead by Wolfe, provides an effective model for identification and surveillance of zoonotic disease on an international scale. Wolfe’s research team works mainly in field sites in Cameroon, where they follow the effects of consumption of bush meat (hunting of wild game for food) in the transmission of zoonotic disease from animals to humans. Not only do the researchers test game as well as hunters for the spread of zoonotic diseases, one of their main functions is to educate people on the dangers of acquiring diseases from the animals they hunt. In order to help hunters protect themselves and their families, the organization distributes filter papers that provide a simple test for blood and body fluids to see if an animal is infected with the disease or not. Each animal that is caught is tested for disease before it is consumed, to reduce the risk of disease transfer to humans. Their approach has proven effective in not only identifying new zoonotic diseases previously undiscovered, it has also stopped the spread of known pathogens (“Nathan Wolfe’s Jungle…” 2009).

Although Wolfe’s project is geared specifically towards identifying disease transmission from wild game to hunters, similar systematic testing of wildlife using filter papers could be implemented in wildlife conservation areas, to test wildlife caught for importation to zoos, and at animal control agencies. Also, similar field sites could be set up in countries identified as high-risk areas to monitor global spread of zoonotic disease. Once zoonotic diseases have been identified, more effort and resources must be placed on finding effective treatments for animals as well as humans so that outbreaks can be halted before they reach pandemic proportions. With the majority of emerging diseases developing from animal species and transferring into the human populations, it is essential that the international health community collaborate with veterinary and wildlife organizations to control and monitor zoonotic diseases as they develop in wildlife and livestock populations. Efforts to control disease transmission to humans from animal species will greatly reduce the likelihood of a devastating global zoonotic pandemic.

References

Cabello, C.C. & Cabello C.F. (2008). Zoonoses with wildlife reservoirs: a threat to public health and the economy. Servicio Agricol Ganchero, 136 (3), 385-393. PubMed.gov. PMID: 18575667

Childs, J. E. Gordon, & Elizabeth R. (2009). Surveillance and control of zoonotic agents prior to disease detection in humans. Mount Sinai Journal of Medicine: A Journal of Translational and Personalized Medicine, 76 (5), 421-428. doi: 10.1002/msj.20133

Cooper, D.W., & Larsen, E. (2006). Immunocontraception of mammalian wildlife: ecological and immunogenetic issues. Reproduction: The Journal of the Society of Reproduction and Fertility, 132, 821-828. doi: 10.1530/REP-06-0037

Nathan Wolfe’s jungle search for viruses (2009, March). TED.com. Retrieved Nov. 20, 2009 from www.ted.com/talks

Parkinson, A.J., & Butler, J.C. (2005). Potential impacts of climate change on infectious diseases in the Arctic. International Journal of Circumpolar Health, 64 (5), 478-86. PubMed.gov

Pavlin, B. I. & Schloegel, L. M. & Daszale, P (2005). Risk of Importing Zoonotic Diseases Through Wildlife Trade, United States. Emerging Infectious Diseases, 15, 1721-1727. doi: 10.3201/eid1511.090467

Survey Wild Animals (2009). Global Viral Forecasting Initiative. Retrieved Nov. 20, 2009 from www.gvfi.org

Tomley, F. M., & Shirley, M. W. Livestock infectious diseases and zoonoses. (2009). The Philosophical Transactions of Royal Society of Biological Sciences, 364 (1530). doi: 1530 2637-2642