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In 1999, per capita pork consumption was about 51 pounds, continuing a steadily-rising trend. The US also exported 438,683 metric tons, the second-leading exporter to Canada. It is also the second-leading producer; China produces more than four times the pork the US does, which is twice as much as Germany, the third-greatest producer, does. However, the US also imported 375,000 metric tons of pork in 1999.


Scientific Origins

Domesticated swine, commonly called hogs or pigs (the latter more properly reserved for younger swine) are cloven-hoofed mammals having long, mobile snouts, thick, bristly hides, and small tails.

  • Species: Scrofa (Latin) a breeding sow.
  • Genus: Sus (Latin) a pig.
  • Family: Suidae
  • Suborder: Suina
  • Order: Artiodactyla (Greek) artios, complete, of numbers even; daktulos, a finger or toe. The Order Artiodactyla is the most successful order of terrestrial ungulates (see definition below) today. There are 3 suborders:
    • Suborder Suina: pigs, peccaries & hippopotami: primitive artiodactyls.
    • Suborder Tylopoda: camels & llamas: intermediate artiodactyls.
    • Suborder Ruminantia: cattle, antelopes, deer and giraffes: advanced artiodactyls.
  • The Artiodactyla did not undergo a major adaptive radiation until the end of the Eocene epoch, some 35 million years ago, even though the first artiodactyls appeared some 20 million years earlier. The three suborders had all separated by the early Oligocene. The Suborder Suina contains the earliest and most archaic artiodactyls. There are 3 families alive today:
    • Family Suidae: pigs
    • Family Tayassuidae: peccaries
    • Family Hippopotamidae: hippopotamii.

Arrival in America

It is believed that the majority of the breeds we now know are descended from the Eurasian
Wild Boar (Sus scrofa). However the two forms are still considered one species. The Eurasian wild boar was described by Linnaeus in 1758. Archaeological evidence from the Middle East indicates that this wild boar was domesticated into what we know as the pig over 9,000 years ago (~7,000 B.C.E.). From the Middle East the pig spread across Asia, Europe and Africa. Swine were probably brought over to the Americas by the first Spanish Settlers.


Food Web/Trophic Levels

Wild Diet:
Seeds, roots, tubers, fruit, nuts, carrion, eggs, insects. In short - ANYTHING.
Farm diet:
Hogs are raised with corn and soybeans.
Main Predators:
Humans, wolf, tiger, lion, leopard, snow leopard.

Hogs provide about one-quarter of the meat eaten in the United States. Hogs are adapted to temperate and semitropical climates and are found in many different areas of the world. The leading countries in numbers of animals in the late 1980s were China, with nearly 335 million hogs; the Union of Soviet Socialist Republics, with more than 77 million; the United States, with more than 53 million; and Brazil, with 33 million. Other leading countries, in descending order, included West Germany, Poland, Mexico, Spain, Romania, the Netherlands, France, East Germany, Vietnam, and Japan. Worldwide, the hog population was estimated at more than 823 million.

In the United States, the swine industry is concentrated in the Midwest in the corn belt. The leading states are Iowa, with about 14 million hogs; Illinois, with 5.7 million; and Minnesota, Indiana, and Nebraska, each with more than 4 million. Other major hog-producing states include Missouri, North Carolina, Ohio, South Dakota, Kansas, Michigan, Wisconsin, and Georgia.


Health Risks

Hogs are highly susceptible to many diseases transmissible to humans, among them trichinosis, actinomycosis, and swine fever.

Trichinosis is a parasitic disease caused by infection with the larvae of the nematode worm Trichinella spiralis, following ingestion of raw or inadequately cooked meat, especially pork. The minute trichina worm is almost worldwide in distribution. The larvae mature in the intestines and are carried by the bloodstream to muscles, where they become embedded and remain. The host experiences irregular fever, profuse sweating, and muscular soreness; these symptoms usually subside soon after infestation, although vague muscle pain and fatigue may persist.

Animals are infected with trichinosis by eating flesh in which the larvae of the trichina worm are encysted. The larvae are freed from their cysts by the digestive juices of their host's intestine; two days after entering the intestinal tract, they become adults and mate. The females burrow into the lining of the intestine and, after six days, begin to bear numerous larvae. Seven days after the encysted larvae have been ingested by the host, the newly born larvae migrate into the lymph channels of the intestine, from which they enter the bloodstream.

From the blood, the larvae penetrate the striated, or voluntary, muscles about 14 days after birth. Within these muscles the larvae mature until they are 16 days old; they then cease developing and form a capsule about themselves from the sheath, or sarcolemma, of the host's skeletal muscle. The host secretes lime salts that are deposited in the capsule, eventually transforming the capsule into a completely calcified cyst.

Trichinosis is most often contracted in humans by eating infected pork. Despite rigid standards of meat inspection in the U.S., infected pork can sometimes pass inspection because the disease is extremely difficult to recognize. Trichina cysts in pork may be destroyed completely by freezing the meat at -15° C (+5° F) for 21 days or -30° C (-22° F) for about 25 hours. Trichina larvae that are not encysted are destroyed when the meat is heated to 66° C (150° F). Ordinary curing and smoking processes do not render pork safe for consumption.

During the stage of infection after the immature trichina worms are freed from their cysts, the maturing larvae cause severe irritation of the intestinal tract. Symptoms of infection include abdominal pain, nausea, vomiting, and watery stools. With the release, or migration, of the larvae into the bloodstream, the face very often becomes puffy and swollen, especially around the eyes, and headache and even delirium occur; the heart muscles also are often damaged. The invasion stage is marked by muscle spasms and pains in the joints. People with trichinosis usually recover in about six months, after the mature larvae become encysted.

Actinomyosis is an infectious disease of horses, cattle, swine, and humans, also called lumpy jaw or big jaw.

Undulant (see definition below) Fever, also known as brucellosis, is an infectious disease caused by various species of bacteria of the genus Brucella, transmitted to humans from lower animals, especially cattle, hogs, and goats. Human beings acquire the disease through contact with infected animals or by drinking their raw milk. The disease has been known as Malta fever, Bang's disease, Mediterranean fever, rock fever, and goat fever. In animals the disease generally can cause partial sterility, decreased milk supply, and abortion of a fetus. In humans, undulant fever assumes acute and chronic forms. The acute form is characterized by weakness, chills, and high night fevers and often results in central nervous system disorders, painful joints, and miscarriage. Chronic undulant fever is difficult to diagnose, as the symptoms are exceedingly varied and vague. Common to almost all cases, however, are remittent fevers and disorders of the central nervous system. A diagnostic blood agglutination test is available. As a rule human beings suffering from undulant fever respond favorably to the administration of broad-spectrum antibiotics. The pasteurization of milk is essential to the control of undulant fever. In addition, the development in the 1950s of a vaccine called Strain 19, with which calves can be inoculated against the disease, has reduced greatly the incidence of bovine undulant fever in the U.S. The organism causing the disease was discovered in 1887 by the British physician and pathologist Sir David Bruce.

The word 'ungulate' comes from the Latin 'ungula', meaning hoof. It has long been used as a term to describe any hooved herbivorous mammal, but the ungulates have not been thought to constitute a single group of closely related animals until recently. The 'ungulates' were considered to comprise the Artiodactyla (even-toed ungulates like pigs or cattle), the Perissodactyla (odd-toed ungulates like horses or tapirs) and various fossil groups of primitive ungulates. The aardvark, elephants and hyraxes were referred to as 'subungulates'. All modern ungulates are descended from Condylarthra, an extinct order of hoofed mammals from the upper Cretaceous period (65 million years ago). A total of 19 orders of hoofed mammals have been identified (including Cetacea), of which only seven have survived to the current day. Ungulates have developed hoofs - specialized claws or toe-nails - as an adaptation for running. They are one of the most successful and diverse groups of mammals, having colonized nearly every habitat.


Ecological Impact

The Facts on Farm Jobs: The Small, Independent Farmer Is Losing the Farm

In North Carolina, the hog industry is an important part of the state's economy, a $2 billion industry and the largest sector in agriculture. Having a viable industry is important to the state's economy, but claims about the hog industry's jobs and other economic contributions must be looked at fairly.

Consider these changes over the last decade:

The number of pigs in North Carolina has exploded from about 2.5 million in 1987 to over 10million in 1997, but the number of hog farms has decreased over 75% from 24,000 individual farms to less than 6,000 farms in 1997.

Since 1983, about three quarters of North Carolina hog farmers have left the business. The industry trend is overwhelmingly towards mega-farms -- industrial-sized hog factories which employ fewer workers and have far more hogs per farm.

Figure 1: The problem with hog production in the US: small farms to mega-factories.

Figure 2: The number of these small farms has been decreasing.

Figure 3: All of the hog inventory is not in the small farms, but rather in the mega-factories.

Source of charts:


Although small farms pollute less, and most of the operations are still small, the number of small farms are decreasing. Most importantly - the bulk of the inventory of hogs are in large 'mega-factories' that pollute a lot.


Why do small farms pollute less?

Large scale hog factories dispose of hog waste in open-air pits called waste lagoons. Some are lined with clay but most of the older ones aren't. The waste is only minimally treated before being sprayed out onto fields.

  • Microbial pathogens
  • Antibiotic resistance
  • Heavy metals
  • Odor

For assistance with general agricultural statistics or further information about NASS or its products or services, contact the Agricultural Statistics Hotline at 800-727-9540, 7:30 a.m. to 4:00 p.m. ET, or e-mail

Hog waste contains more concentrated organic matter than human waste...Nitrates, copper, antibiotics, and other chemicals harmful to humans in large doses.

Yet, none of the safeguards and regulations applicable to the smallest city waste disposal system apply to hog factory lagoons.


Where is the pollution coming from?

Table 1: 1997 Hog Waste Summary
of Heads
of Waste
(106 tons/yr)
of Waste
(106 tons/yr)
in Waste
(106 tons/yr)
Nitrogen Lost
to Atmosphere
(106 tons/yr)
in Waste
(106 tons/yr)


Hog Waste Trends

  • Iowa increased by 13% since 1987
  • North Carolina increased by 282% since 1987
  • Minnesota increased by 35% since 1987
  • Illinois decreased by 17% since 1987
  • Indiana decreased by 10% since 1987


Rearing Practices

Swine are raised under more intensive conditions than cattle and sheep. Such enterprises fall into three broad groups: production of purebred breeding stock, production of feeder pigs, and growing and finishing of feeder pigs for sale and slaughter. Some producers carry out all three activities, and recently many of them have formed cooperatives and built large farrowing units, where up to 1000 sows can give birth. When the young feeder pigs are weaned at these large units, the individual members of these cooperatives buy them back for feeding and finishing.

Intensive production requires expert management and the cooperation of several different specialists, such as veterinarians and nutritionists. Feed costs account for about 75 percent of the total production costs, so careful selection of feeds for their nutritional adequacy and economy is important. Many other important elements must also be controlled when swine are raised under confined conditions. Newborn pigs are highly sensitive to cold. In addition, pigs have no sweat glands, so larger pigs must have facilities for keeping cool in warm environments. Proper ventilation also removes toxic gases, primarily hydrogen and ammonia from waste products. In addition, because the animals are confined in intensive production units, they must each be allotted a given amount of space. This ranges from about 0.3 sq m (about 3 sq ft) for each young pig to approximately 1.4 sq m (about 15 sq ft) for brood sows.

Under confinement, disease is controlled by vaccination, control of wildlife carriers of disease, antibiotics, and, in some cases, eradication of the disease-producing organisms. Compounds that can control the reproductive cycle, the length of the gestation period, and the timing of births have made it possible to control the breeding and farrowing so that a minimum of labor is required during weekends, when such labor is more expensive.



One hog produces three times the waste a person does. The current method to dispose of all this hog waste is primitive. Unlike human sewage, which is treated and disinfected, hog waste is collected in open-air pits (called waste lagoons), where it is minimally treated then sprayed on land.


Polluted Soils, Rivers, and Shorelines

Hogwaste contains large amounts of nitrogen and phosphorus, nutrients which can cause excess algae growth, rob the water of oxygen, and kill fish when too much is present. Hog waste pollutes North Carolina's waterways and soils through waste spills, leaking waste lagoons, and run-off from fields where waste is sprayed.


Air Pollution

Huge quantities of ammonia nitrogen escape into the air from hog operations and come back down on waters and soils downwind. Preliminary analyses indicate that hog factories pour more nitrogen pollution through the air alone into North Carolina estuaries than all of the discharges from municipal waste water treatment plants and industrial factories combined! Other studies have found that air pollution from hog factories can cause respiratory illnesses in neighbors living up to two miles away.


Contaminated Groundwater and Drinking Wells

Leaking waste lagoons and runoff from sprayfields (land near the hog lagoon on which the hog waste is applied by high-powered spray guns which spray the hog waste high in the air, allowing it to drift back onto the land) can contaminate groundwater. Recent state analyses found abnormally high levels of nitrates in 10% of the drinking wells near hog and chicken operations. Nitrates are nitrogen-containing compounds that are water soluble and mobile in the environment. Nitrates are toxic at elevated concentrations (public health standard set at 10 parts per million). Groundwater nitrate contamination can present a threat to public health.


Odor Pollution

Horrible odors from hog factories can destroy neighbors' quality of life. New studies are finding evidence of other threats to public health and the environment:



Hog waste processed by current waste treatment systems and sprayed onto land contains 100 to 10,000 times as many pathogens (disease-causing organisms), as human waste that is treated and applied to land.


Antibiotic Resistance

Frequent exposure to an antibiotic provides conditions favorable to the evolution of germs which are resistant to (i.e. not harmed by) that antibiotic The large number of hogs confined to small areas requires constant use of antibiotics in their feed to prevent disease. These are the same antibiotics used by humans for diseases that are often shared by hogs and people. Some scientists say we are "playing with fire" because overuse of antibiotics is known to encourage development of germs that are resistant to antibiotics.


Heavy Metals

A classification of elements, many of which are necessary for animal nutrition in trace quantities but which are also toxic to plants and animals in low concentrations. Hog feed is fortified with heavy metals, notably copper and zinc, which can be toxic to plants and animals, even in low concentrations. Most of these heavy metals end up in the hog waste, ultimately becoming concentrated in the solid sludge which accumulates in the waste lagoon. Often this sludge builds up in the lagoon for 10 to 20 years before it is finally removed. By that time, the concentration of heavy metals is so high that getting rid of it safely is difficult.

While hog waste contains nutrients and organic matter that historically have been the major concern of the industry and those who are trying to help the industry with waste treatment and waste management practices, there are in addition to those constituents, microbial contaminants that include disease-causing microorganisms of humans. In fact, the majority of enteric bacteria, parasites and even viruses that are caused by fecal oral transmission, that is from fecal contamination that occur in humans, the majority of them can occur in swine and other agricultural animals. We also must keep in mind that the concentration of these pathogens in hog waste is likely to be much higher than the concentration in municipal raw sewage. Raw sewage is diluted with a substantial amount of clean water that we flush down our toilets and wash our clothes with and wash our dishes with and the like. Whereas, in hog operations there is a recycling and savings of water in order to minimize water usage and, therefore, hog waste compared to human sewage is probably 10 to 100 times more concentrated. Therefore, if there are disease-causing microorganisms that are fecally shed by the hogs, they're going to be at much higher concentrations in hog waste than in human waste.

Municipal wastewater is extensively treated by processes that are designed not only to reduce nutrients and organic matter, but also to reduce pathogens. We also require that municipal wastewater be disinfected before it is discharged to the environment. In the case of hog waste and other animal waste, the treatment by comparison is considerably less. In hog waste, treatment is typically anaerobic lagoons with advertised residence times of six months, and such treatment, we have found from our research, achieves only nominal reductions of the microbial indicators of fecal contamination

We have to be concerned with the impact of those pathogens that might be land applied on the environment and what the potentials are for human exposure. What are those roots of exposure? Well, contamination of ground water would be one potential root of exposure- growth from the land-applied wastewater- as well as from leaking of the lagoons themselves. And we know that some of these pathogens are readily mobile in ground water. The viruses and bacteria in particular are small enough that in the sandy shallow water table coastal plain soils of North Carolina, there could be potential for substantial microbial contamination of groundwater. There is also the potential for contamination of surface water because the land applied waste can be washed from the surface of the land by precipitation events, rainfall that might occur shortly after application, or if the spraying is not done carefully there could be spraying directly into nearby bodies of water.

We have shown that even under best management practices for land application of animal wastes, there are impacts on nearby bodies of surface water. That is, the levels of microbial indicators of fecal contamination in streams adjacent to animal waste management operations even under best management practices can rise by an order of magnitude or more - ten to perhaps a hundred fold increase - which again shows the potential for microbial pathogens getting into those waterways. We also have to be concerned with regards to the spraying of this waste for aerosolization or airborne exposure to microbial contaminants. Studies have shown that the wastewater is aerosolized. There are microbes in the airborne state. They can be carried over great distances and certainly some of the pathogens would survive aerosolization to represent yet another source of exposure from airborne exposure. That exposure could occur over great distances. Therefore, we know that there are potential roots of transmission whereby humans could get exposed to pathogens that might be released with hog waste.

The quality of life in rural farming communities has dramatically changed for many people. Many property owners, long accustomed to the everyday smells associated with farming, are now plagued by unbearable odors from neighboring hog factories. Others can no longer drink their own well water. Although odor is difficult to measure, scientists have recognized that it can be harmful to people, causing problems ranging from psychological stress to respiratory illness.


Hog Farms

Don't be misled by the term "hog farm." The modern-day hog factory has little in common with the traditional family farm of yesteryear. The modern hog farm is a large scale, highly-mechanized operation, much like a typical industrial factory. In hog factories, hogs live their entire lives packed together in big warehouses the size of football fields, called "hog houses." A single hog house can contain 800 to 1,000 hogs. One "farm" in the state actually has capacity for 68,000 hogs. Those 68,000 hogs could produce nearly as much waste as all the people living in Raleigh.

In North Carolina, factory-size farms have become the norm. About 9 out of every 10 hogs in the state are raised on factory farms. What's more, North Carolina leads the nation in mega-factories housing more than 5,000 hogs. North Carolina has 480 of these mega-factories, over twice as many as any other state. Sadly, many small independent farms have been forced out of business. North Carolina has lost more than 50% of its smaller family hog farms in the last 15 years. Small hog farmers are simply unable to compete with the market clout of mega-industry. The message? Get big or get out.


In 1991, Smithfield Foods built the world's largest hog slaughterhouse and packaging plant in eastern North Carolina. This plant, capable of slaughtering 24,000 hogs each day, paved the way for the construction of hundreds of new factory hog farms. In fact, the state's hog population has more than doubled since the slaughterhouse was built, prompting state officials this year to deny the plant's request to expand.


Few Regulations

Most of North Carolina's explosive growth occurred before hog factories were even regulated. New laws and rules have done little to slow this growth -- even with a moratorium on construction of new farms in place, the state's hog population grew by 750,000 in 1998.

The North Carolina pork industry is a $2 billion business. And, from 1990 to 1997, overseas demand for US pork skyrocketed. US pork exports quadrupled from 82,187 metric tons to 324,507.

Hog factories and traditional family hog farms are two very different animals. But for the most part, North Carolina law treats them as though they were the same. In fact, before 1993, North Carolina had almost no regulations whatsoever in place to reduce pollution from the millions of hogs grown on factory farms. In recent years some progress has been made, but the new laws have not gone far enough.

  • Thousands of hog factories are exempt from newer siting restrictions, zoning ordinances, and other rules.
  • Even under the current laws and regulations, new factories are still allowed to use primitive open-air waste lagoons and sprayfields to dispose of vast amounts of hog waste.
  • There are virtually no rules in place to limit the concentration of hog factories in environmentally sensitive or important watersheds, or in populated areas. Some rural residents are literally surrounded by hog factories!
  • Hog factories are still not required to monitor groundwater or surface water, defined as water flowing on surfaces such as rivers, streams, lakes, estuaries, and oceans.
  • Odor is still entirely unregulated.
  • Hog factories are allowed to spray waste within 75 feet of their neighbors' property and nearby streams.
  • The companies who own the majority of the state's 10 million hogs are not held responsible for environmental violations which occur at the contract farms where their hogs are raised.
  • The pork industry boasts that fewer than 1% of factory farms have trouble complying with state environmental rules.
  • Let's get serious. In the first nine months of 1998, state inspectors found 1,293 violations and deficiencies at hog factories. Over 900 of these violations were serious and included 86 discharges from waste lagoons, 221 instances of applying too much waste on the land, 585 cases where waste lagoons were too full, and 8 cases where hog factories located too close to neighbors or environmentally sensitive areas.
  • Factory hog farms are inspected only twice a year, and state officials give the hog factory advanced notice that they're coming. Thus the actual number of violations is probably much higher than the data indicates.
  • Even factories that comply with all current rules still pollute the environment through unregulated emissions of ammonia and offensive odors. We now know that air emissions of ammonia put more nitrogen into coastal North Carolina than all municipal and industrial sources combined. Agricultural runoff, including runoff from fields saturated with hog waste, continues to be the number one source of nutrient pollution in North Carolina - by far.


Nutrient Pollution

Pollution containing nitrogen and/or phosphorus which stimulates aquatic algal growth, thus robbing waters of oxygen and killing fish and other aquatic organisms. Nutrient pollution comes from runoff of excess fertilizers, animal waste, and other diffuse sources, as well as from waste water treatment plants and some industries.

Sewage treatment plants have been regulated for decades. Hog factories were almost entirely unregulated until 1993 and, even now, are exempt from many of the environmental rules that apply to sewage treatment plants.

The problems with hog factories actually start at the loading dock. Because corn and other hog feeds are not farmed extensively in North Carolina, to feed the state's 10 million hogs, factory farms must bring in train car after train car of grain from the Midwest. This grain is loaded with nitrogen and phosphorous, which the hogs eat, digest, and excrete. Only a small percentage of the grain is converted into meat. The remainder is turned into hog waste and disposed of in North Carolina's environment. This means much of the nitrogen and phosphorus stored in hog feed ends up in hog excrement and ends up in North Carolina's soil, air, and water.

Hog factories have nurseries, sow farms, and adult hog houses. Hog houses are the huge barns where hogs spend their entire adult lives. Hog houses can be as big as football fields, and can hold 800 to 1,000 pigs packed together. Every single hog in the hog house dumps over 10 pounds of urine and feces per day, or almost 2 tons per hog per year. This hog waste falls through steel grates underneath the hogs' cages and sits on a concrete slab underneath the hog house. Here, odor and nitrogen ammonia are carried by wind to nearby land, water, and noses.

Several times a day, hog waste is flushed with water from the hog house, carried through pipes, and dumped into an open-air pit, called a waste lagoon. Waste is held in the lagoons for up to six months, where it receives minimal treatment. Older waste lagoons are not lined -- they are simply holes dug into the earth. Newer waste lagoons are required to use a clay liner to reduce the amount of waste which can leak out of the pit.

As of October 1998, North Carolina has over 4,600 waste lagoons. These can threaten people and the environment in major ways.


Waste Lagoons

Waste lagoons produce gases that contribute to pollution. Bacteria starts to break down the hog waste sitting in the lagoon, and produces a number of gases including ammonia (a form of nitrogen) and methane. Ammonia and methane are volatile, which means they turn into gases and rise out of the waste into the air. What goes up must come down, and most of this ammonia and methane eventually fall back to earth somewhere in the coastal plain of North Carolina or beyond.

Waste lagoons house toxic sludge that may pose serious clean up problems. In the waste lagoon, solids and liquids separate. The solids form sludge that sits on the lagoon bottom for 10 to 20 years, until it is removed and land-applied. The solids contain several compounds, including heavy metals (copper and zinc that are toxic to plants and animals), and phosphorus. As of October 1998, North Carolina has 643 "inactive" waste lagoons. These "inactive" lagoons contain toxic sludge and are awaiting clean out.

Waste lagoons can leak into the ground, contaminating groundwater and drinking wells. Waste lagoons are actually allowed by law to leak, so long as the waste lagoon surface does not drop by more than 0.036 inches a day. This may not sound like a large amount, but over the course of a year, a single three acre waste lagoon could leak up to a million gallons of waste. Studies show that shallow groundwater drinking wells below hog and chicken farms have major increases in nitrates, a form of nitrogen. High levels of nitrates are dangerous to humans, especially pregnant women and babies, and can cause abortions and "blue baby syndrome" (a disease affecting the blood's ability to absorb oxygen).

As the waste lagoon fills up, its excess liquid is pumped through pipes and hoses and sprayed onto nearby land. This land, known as the sprayfield, is planted with crops or grasses intended to remove some of the chemicals present in the liquid waste.

Spraying projects large amounts of ammonia nitrogen into the air. This ammonia eventually rains down on land and water. Spraying also magnifies the odors from hog waste by sending millions of moisture droplets drifting through the air and across neighbors' properties.

Problems continue when waste settles on the field. In theory, the grasses or crops should absorb the majority of the waste and its nitrogen-loaded contents. In reality, hog waste often cannot be efficiently absorbed in such enormous quantities. So the excess often washes off during rains and flows through ditches into nearby streams and rivers. The pollution eventually finds its way downriver to North Carolina's sensitive coastal waters, leading to water quality problems in important recreation areas and fish breeding grounds.

In addition, a sprayfield is difficult to manage properly in wet climates like that of coastal North Carolina. Spraying in wet conditions virtually guarantees that the majority of the waste sprayed will run off into nearby waters. And those same rainy conditions can also fill waste lagoons with rainwater, requiring hog farmers to either spray onto wet fields or risk having their lagoons overflow. During North Carolina's rainy season, spraying onto wet fields is difficult to avoid. North Carolina law requires no monitoring to determine the amount of waste which runs off sprayfields.

Sadly, the fine old farming tradition of recycling waste as valuable fertilizer is often misleading in the case of hog factories in North Carolina. Hog waste can be a valuable source of important nutrients (e.g., nitrogen and phosphorus) and, as such, can be used to fertilize economically valuable crops and grasses. However, in the majority of cases, producers spray hog waste on fields of bermuda grass, which has a high nitrogen uptake but low economic value because the market is already saturated with bermuda grass. Transporting the grass to use elsewhere is economically inefficient beyond a certain distance from the field. Furthermore, if the grass is grazed by livestock animals, as little as 10% of the nutrients in the bermuda grass will actually be converted into meat -- the rest is deposited on the field as animal waste. (Put another way, about 90% of what an animal eats leaves its body as waste.) This leaves a producer right back where he/she started from -- trying to "get rid" of hog waste instead of using it to obtain a value-added product.


Common Myths about Hog Farming

Hog factories do not discharge waste into streams or rivers.
Hog factories discharge waste into streams and rivers in several ways. First, state inspectors documented more than 115 illegal discharges from hog waste lagoons in the first nine months of 1998. At least 32 of these discharges reached surface waters. Second, hog waste runs off from farm fields into nearby streams. So far in 1998, state inspectors have found that more than 200 hog factories have sprayed too much waste on their land, virtually assuring that this waste will leach into groundwater and runoff into nearby waterways. Hog factories are not required to install buffers along streams to reduce the amount of waste runoff. Third, waste can and does leak from lagoons and sprayfields into shallow groundwater which, in turn, often flows through the ground into nearby streams. Fourth, hog factories also emit into the air huge amounts of unregulated ammonia nitrogen gas. This nitrogen then is redeposited onto the landscape and waterways, choking rivers and estuaries already impaired by too much nitrogen.

Hog factories do not threaten neighbors' drinking wells.
Hog factories can and do contaminate groundwater supplies--and neighbors' drinking wells--from both leaky waste lagoons and sprayfields. For example, a 1998 analysis by the state found that more than 10% of private wells tested near factory hog and chicken farms were contaminated with excessive levels of nitrates. (Nitrates are toxic and can be especially dangerous to infants.) Follow-up investigations have linked hog production facilities with some of these contaminated wells; additional investigations are ongoing to determine the extent to which hog farms are to blame for other contaminated wells. No one knows just how much is leaking from the nearly 4,000 lagoons in North Carolina because hog factories are not required to monitor leakage from lagoons.

Only a very few "bad actors" in the hog industry violate state water quality laws. Most hog companies obey all laws and don't pollute.
In 1997, 88 percent of all factory hog farms had at least one permit or waste management plan violation. Ten percent actually had water quality violations. So far in 1998, state inspectors have found over 1,366 plan and permit violations. Of these, state officials found waste being discharged from 115 waste lagoons, 599 lagoons that were too full, and 224 cases where factories sprayed too much waste on already saturated fields. These numbers surely underestimate the actual number of problems because hog factories are only inspected twice a year!


How Hog Factories Are Affecting the Fishing and Tourism Industries

Excessive nutrients from hog factories and other agricultural sources are contributing to the severe nutrient pollution, algae blooms, fish kills, and diseases that are threatening North Carolina's tourism and fishing industries. In fact, poor water quality caused by nutrient pollution has helped contribute to the collapse of over 60% of North Carolina's commercial fish species. The impacts of these problems affect all of us in North Carolina -- from the commercial and recreational fishing industries and families dependent upon them, to the state's $2 billion coastal tourism industry, to citizens everywhere in the state who cherish North Carolina's valuable coastal resources.

Tourism is the state's number two source of revenue, bringing $10.1 billion into the economy, and employing 250,000 North Carolinians. Without the jobs created by tourism, North Carolina's 3.5% unemployment rate in 1997 would have been 8.1%. Coastal tourism alone means about $2 billion for the state.

North Carolina is considered one of the best spots in the country for vacation -- second only to Florida. Vacationers overwhelmingly select "clean healthy environment" and "natural beauty and scenic areas" as the two most important attributes in their decision for where to travel.

The coastal fishing industry is of major social and economic importance in North Carolina. Commercial fishing is a $1 billion industry, and recreational fishing brings hundreds of millions of dollars to the state. The health of waterways is clearly critical to the health of this industry.

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