Problem with Poop
The Satya Interview with Amy R. Sapkota
Hen in a manure pit. Photo courtesy of
Industrial animal production has not only consolidated
sentient individuals into intensely concentrated areas, but also their
1.4 billion tons generated annually. With the rise of Concentrated
Animal Feeding Operations or CAFOs, animal waste has become a big environmental
and health problem.
At the Center for a Livable Future at Johns Hopkins University, Dr.
Amy R. Sapkota is researching how different agricultural practices
affect the environment and public health. As research director of the
Industrial Animal Production Project,
she is looking at the impacts of animal waste from CAFOs, particularly hog farms.
The project was inspired by animal activist Henry Spira and collaborates with
the factory farm project at GRACE (Global Resource Action Center for the Environment),
which helps communities confront CAFOs. The goal of this project is to address
the impact of industrial animal production and apply these research findings
to the development of good public policy initiatives.
While currently in France doing research on transgenic plants, Dr. Amy
Sapkotaspoke with Sangamithra Iyer about her research.
How did you get involved in studying Concentrated Animal Feeding Operations or
There are many different reasons why I’ve pursued this research. There
hasn’t been a lot of rigorous research conducted that has looked at the
specific environmental and public health effects associated with CAFOs. And part
of this is due to the fact that it is hard to gain access to these facilities,
as well as the communities around them. Producers don’t want researchers
negatively impacting their livelihood if the research findings are not in favor
of their production methods, and sometimes communities are also reluctant to
get involved with research activities.
I wanted to come from a rigorous scientific approach, studying what we need to
understand in terms of air emissions and waste emissions from these facilities,
and what specific ways they are affecting the environment and human health. I
also wanted to generate hard data that demonstrates what is really going on with
these facilities, instead of being clouded by public perceptions and misconceptions.
I think we can only move forward with better policies regarding the regulation
of CAFOs if we have good science to back them up.
Can you talk about the impact of animal waste from factory farms on the environment
First, animal waste is not a bad thing. In sustainable agriculture it is something
that is used for fertilizer for crop production. From my perspective the problem
lies in the concentration of these facilities. If they were more strategically
located, further away from each other and also smaller in size, we wouldn’t
have such a concentration of waste in just one area. For example, we are not
really producing that many more hogs than we were in the 1950s, but they are
all produced in very concentrated regions in the U.S. versus being scattered
over the roughly three million hog farms that existed in the 50s.
With CAFOs, there is just so much waste produced that there really isn’t
a sustainable way to manage it. Also, because of some of the production methods
used in CAFOs, the waste can contain things that are harmful like heavy metals
such as arsenic. Through our research, we are also finding high levels of antibiotic
resistant bacteria in this waste as well. We believe this is largely due to the
non-therapeutic use of antibiotics in these facilities.
What are some of the differences or similarities among pig and poultry CAFOs?
Poultry are a lot smaller than hogs, so in your average poultry house, you can
have 30,000 to 40,000 birds, versus a typical swine house that can have 2,500
to 3,000 hogs.
With respect to waste, poultry waste is usually a lot drier. Poultry houses are
cleaned out once every one or two years—not too often. The poultry waste
is then stored in what is called a windrow, which is essentially a very large
pile of waste that is generally stored in some sort of large shed. That waste
is then either land applied, incinerated, or pelletized for future use as a fertilizer
Pig waste is more of a liquid product and is either stored in lagoons or pits
beneath barns. It is usually siphoned off with some sort of truck or piping system
and sprayed on fields either onsite or offsite. In the lagoons and pits, solid
material settles to the bottom. In theory there is anaerobic decomposition of
the solids, but if a large amount is being dumped into these lagoons, the question
is, is there enough time for the decomposition to take place?
I was wondering if you could comment on chicken waste and its impact on the Chesapeake
One of the problems is the physical location of a lot of the poultry operations.
Many are in ecologically sensitive areas, such as the Delmarva Peninsula, which
is essentially the eastern shore of the Chesapeake Bay that is shared by Delaware,
Maryland and Virginia. The whole Delmarva Peninsula is not only one of the largest
poultry producing areas in the country but also [part of] Chesapeake Bay watershed.
Therefore, much of the poultry waste that is produced and land applied in this
sensitive ecological watershed can ultimately end up in the Bay.
What do you find to be the biggest human health risks of factory farming?
Based on the research I’ve conducted, the problem of antibiotic resistant
bacteria developing in these operations is one of the key issues. The resistant
bacteria can end up on food products, as well as in the air and water surrounding
I also believe that the use of arsenic, a known human carcinogen, in both poultry
and swine production is a significant issue. Producers are using an arsenical
compound known as Roxarsone as a feed supplement for our poultry and swine. Arsenic
is not only a food safety issue, but also an environmental issue, as it could
potentially end up in our surface waters and groundwater. Because it is a heavy
metal, you can’t get rid of it. For example, even if you incinerated the
waste, you are just going to be releasing the arsenic into the air.
What are the other risks that CAFOs pose in terms of air pollution?
Many different compounds are emitted from CAFOs. For example, in swine air emissions,
there are over 160 compounds that have been characterized. Those include particulate
matter such as dust, particles of skin, and particles of fecal matter. There
are also gases, including methane, hydrogen sulfide, and ammonia. Volatile organic
compounds that haven’t been fully characterized are emitted as well.
It is generally the odor associated with these plumes and emissions that is causing
people to challenge CAFOs in their areas. It is very difficult to live with that
sort of odor on a daily basis.
It seems that hog farms in general are more notorious.
You do see more attention to swine farms in terms of community health effects.
However, I don’t know whether the reason is that there has been very little
research conducted in communities that are located around poultry facilities,
or whether the people who live around hog facilities have a more powerful or
stronger voice, or are more organized. I am not exactly sure why the hog facilities
are receiving more attention. It also might be because of location. Perhaps the
hog farms are located in more densely populated areas versus the poultry facilities.
I know the factory farm project at GRACE works with communities affected by CAFOs.
Have you been directly involved with communities confronting CAFOs?
I can give you an example of one activity that I was personally involved in.
This occurred in the Peach Bottom Township in Pennsylvania where there was a
proposal for the construction of a swine CAFO in an area where there were over
3,000 homes. The community sought the advice of a number of different people.
We provided testimony regarding the public health and environmental effects associated
with such facilities. Fortunately for the time being, Pennsylvania has not approved
the construction of this particular swine CAFO.
I understand that your project inspired by Henry Spira hopes to be a “do” tank
rather than a “think” tank. What is it you hope to do?
We use our research findings to try to move forward good public policies. A good
example of this is that the director of the Center for a Livable Future, Robert
Lawrence, recently testified in front of a congressional house subcommittee.
There is a current bill in Congress that is proposing to remove animal waste
from the regulatory purview of the superfund law, which is the Comprehensive
Environmental Response Compensation and Liability Act. In response to this proposal,
Dr. Lawrence testified on the public health and environmental health effects
associated with CAFOs and his testimony included many of our research findings
coming out of the Johns Hopkins Bloomberg School of Public Health.
We are not only doing research and publishing it in peer-reviewed journals, but
we are trying to speak about our findings in settings that can actually have
an impact on federal policies.
Can you talk a bit more on some of the public policy initiatives?
Currently, the Bush administration is whittling away at some of our strongest
environmental laws, including the Clean Air Act and the Clean Water Act. In general,
we work to prevent these laws from being eroded even more. These laws are very
important in terms of controlling both airborne emissions and waste emissions
from CAFOs. The CAA covers airborne emissions, including particulate matter and
hydrogen sulfide, and the CWA has a program called the National Pollution Discharge
Elimination System, which covers waste related discharges coming from CAFOs.
We are trying to use our research findings to maintain the effectiveness of these
types of laws.
How have you found getting access to information about CAFOs?
It is difficult to gain access to these facilities to study them in the first
place. However, there are some producers who do want to be good environmental
stewards and don’t want their farming practices to be negatively impacting
the environment and public health. You have to seek out these like-minded people
and work with them.
In terms of data, it is very difficult to gain access to the types and amounts
of antibiotics being used in CAFOs. In the U.S., this important data is just
not collected. To study antibiotic resistant bacteria coming from these facilities,
it is nice to know as a starting point what antibiotics are actually being used.
Unfortunately, even some of the producers don’t know precisely what antibiotics
are in the feed, because the feed is often delivered by the larger company that
they contract with and is siphoned into their silos. Sometimes a producer is
willing to collaborate with you to do research, but they still might not have
all of the answers about what exactly is in the feed.
In contrast to the situation in the U.S., some of the European countries, like
Denmark, have excellent systems where they collect data on how much and what
types of antibiotics are being used in the feed.
You’ve mentioned the potential erosion of some of our strongest
laws. Can you comment on policy initiatives regarding animal welfare?
Unfortunately, that is also a big difference between the U.S. and Europe. Europeans
in general, and European scientists and policy makers, are more aware and interested
in animal welfare. They have more regulations on the books than the U.S. does.
In discussing the impact of antibiotic resistant bacteria, are there links being
made between the conditions in which the individuals are kept in these facilities
and the need for antibiotics?
The reason they are feeding non-therapeutic levels of antibiotics is primarily
to promote growth. It is an economic reason—getting the animals to market
as efficiently and quickly as possible. There is a question as to whether animals
can be raised under confined conditions in the U.S. without the use of any antibiotics.
We know that this is being done in Europe where the usage of non-therapeutic
levels of antibiotics has been replaced by better management and hygienic practices.
Researching factory farms, you probably have some interesting stories. Is there
anything in particular you feel compelled to share?
It’s hard to make overall statements because each of the facilities we’ve
visited has had their own quirks. However, the odor of swine is probably one
of the most intense odors I’ve ever smelled. As an example of this, the
odor truly sticks to our notebooks and our equipment for years after sampling
in the facilities. It is a very sticky, intense smell that really stays with
you even after your research is finished.
Has working on these issues affected your own personal dietary choices?
Well, I’ve been a vegetarian my whole life almost. I grew up in a family
where my mother was vegetarian. So, no.
To learn more about the Center for Livable Future visit www.jhsph.edu/clf. To
find out more about factory farms and what to do if a CAFO comes to your town
go to www.factoryfarm.org.