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Hudson Sustainability Report, part 2
Pesticides
The use of agricultural pesticides has long been one of the most hotly
debated issues in environmental and agricultural circles. The claim is that
they are unsustainable due to their impact on the environment, wildlife, and
human health, and the development of resistance in the pests. But a careful
and thorough look at these issues fails to support the claims.
In fact, there is tremendous evidence that the chemicals greatly enhance
farming’s sustainability.
Sustaining High Yields: The assertion that agrichemicals have damaged the
environment to the extent that future production has been decreased is
refuted by the ever increasing yields on our fields. Every high-yield farm
is a long-term testament to the viability and sustainability of today’s
agricultural practices, including pesticide and fertilizer use. The
University of Illinois’ Morrow plots and the Rothamstead Plots in England
which go back many decades, along with other objective scientific studies of
long-term farm productivity support this assertion.
The point is often raised that pest damage worldwide has increased
dramatically despite pesticide use. But the real question is how high crop
losses would have mounted without pesticides and how much extra land would
have been needed to compensate for the losses.
(We must also note that organic producers also use large quantities of
“organic” pesticides. Would pest damage decrease without organic pesticides?
Are organic pesticides exempt from the accusations of environmental impact
leveled against synthetic pesticides?)
Pest resistance to pesticides is also raised in discussions of pesticides
and sustainability. But pests will always adapt to overcome obstacles. Our
only solution to pest adaptation is constant development of new pest
resistant crops, pesticides with new or altered modes of action, and prudent
approaches to slowing the development of resistance in the pests. There is
every reason to believe that we can continue to stay ahead of pest and
disease organisms, especially in light of the potential of biotechnology. We
cannot sit still on any broadly-used pest controls, even organically derived
pyrethrins.
The claims that agricultural pesticides wreak havoc on natural ecosystems
are unrealistic for today’s highly specific, low-volume, and short-lived
pesticides. In addition, today’s chemicals are applied very carefully so
that virtually all of their impacts are within the fields where they are
applied. For example, less than 1 percent of the herbicides applied in the
U.S. leave the root zone of the fields. The fields are far from being
pristine natural environments; we can hardly burden our farmers with the task
of creating ideal wildlife habitat within their fields while still demanding
they protect the real wildlands from the plow with high yields.
SIDEBOX:__________________________________________________________
The Latest Charge: Estrogen Imitators
Environmental activists are running out of credible objections to
agricultural chemicals. Their claims, as a result, have become more nebulous
and difficult to prove (or disprove.) The latest of these claims is that
pesticides and other chemicals are “mimicking” estrogen, bioaccumulating, and
disrupting the endocrine systems in both humans and wildlife.
One environmental writer used this sinister imagery: “Sneaking into [the
endocrine system], in which timing and dose of hormones are so crucial,
chemical hormone copycats lurk, waiting to ambush the endocrine system.”
(From Fertility on the Brink: The Legacy of the Chemical Age, a report by the
National Wildlife Federation, Washington, D.C., 1994.)
The health problems attributed to this phenomenon are supposedly “subtle” or
“sub-clinical,” and may appear as “gender confusion,” reduced sperm counts
and smaller sex organs.
The wording of their argument is telling: “scientists speculate that ...,
scientists theorize ..., What is new is the understanding that ...” (emphasis
added.)
The eco-activists have deliberately lumped safe and short lived herbicides
such as atrazine and 2,4-D (which are weak estrogen imitators), with
extremely harmful chemicals like PCBs and heavy metals (lead, mercury and
cadmium). They’re trying to prove guilt by association. But lumping proven
health threats like PCBs with farm chemicals is no more rational or
scientifically valid than condemning garter snakes because cobras are
venomous.
Unfortunately for the eco-activists, not much of the evidence for this theory
holds up to scientific scrutiny. A critical review of this theory, by Dr.
Stephen Safe of Texas A&M University, appeared in Environmental Health
Perspectives and discusses in detail the theory’s shortcomings. As example,
the reports of a reduction in human sperm count and quality over the past 40
to 50 years, which garnered lots of publicity, have been refuted by prior
and subsequent reports, as well as a reanalysis of the data used in the
original study.
Additionally, as the table below indicates, humans are exposed to a vastly
greater amount of estrogen-mimicking compounds in the form of natural food
flavonoids, than from environmental pollutants. The natural flavonoids
represent 40 million times more daily estrogen equivalent than the traces of
environmental organochlorine pesticides to which we are exposed.
Table 3. Estimated mass balance of human exposures to environmental and
dietary estrogens.*
Source Estrogen Equivalents (*g/day)
Estrogens
Morning after pill (RU 486) 333,500.0
Birth control pill 16,675.0
Post-menopausal therapy 3,350.0
Flavonoids in foods (1,020mg/day x 0.0001)
102.0
Environmental organochlorine estrogens (2.5 x 0.000001)
0.0000025
*Adapted from Environmental and Dietary Estrogens and Human Health: Is There
a Problem?, Environmental Health Perspectives vol. 103, num. 4: 346-351,
April, 1995.
________________________________________________________________________
Wildlife: Agrichemicals are not a documented threat to the survival of a
single species. We aren’t seriously threatening even the species we are
deliberately trying to eradicate, like the cotton boll weevil. Habitat
destruction is undoubtedly the greatest threat to wildlife, and, as such, it
is the acres not plowed that are important. By allowing us to produce food
and fiber from fewer acres, pesticides and fertilizers help us leave acres
uncultivated as habitat for wild organisms.
Heavy emphasis has been placed on wild ecosystems and their role in
sustainability without acknowledging modern agriculture’s contribution in
protecting them. High yields are all that stands between habitat and
plowdown for huge tracts of the world’s wildlands.
Several studies have been conducted to determine the yield differences
between farming with and without pesticides. Yields in field crops would
drop between 24% and 57% without pesticides according to a study from 1990.
Wheat yields would be harmed the least at 24%, but corn yields would be cut
by 32% and rice by 57%. One study on fruit and vegetable production
concluded that yields would drop from between 50% and nearly 100% depending
on the crop and location. (In fact, many areas wouldn’t economically
produce the crops they currently do, because pesticides are the only
protection against near total crop loss from pests and disease, such as
Georgia’s famous peach crop.) Another study concluded fruit and vegetable
consumption would decrease by 11% due to higher prices and that acreage
required for production would increase by 44%. Whether yields fall 100% or
25%, more land would be necessary to produce the current food output. That
means more habitat plowed down and higher prices for the fruits and
vegetables needed by poor children.
This is not, of course, a blanket endorsement of complete environmental
safety for each and every individual farm chemical in use in all applications
today. Nor is it an excuse for overusing such chemicals. It is only a
recognition of the overall safety of synthetic pesticides and their
contributions to productivity.
There are certainly examples of pesticides harming wildlife. Where
significant patterns of harm are documented, specific chemicals or uses
should be (and are) eliminated.
Recently, the Wallace Institute for Alternative Agriculture published a
critical report on the environmental consequences of high-yield farming
systems. However, their worst example of wildlife harm from pesticides has
disappeared. “Researchers in the James River area of Virginia estimate that,
even as late as 1991, at least six percent of the breeding population of bald
eagles was being killed annually from secondary insecticide poisonings.”
Apparently the Wallace Institute was unaware that the eagle deaths had
been caused by a single pesticide, or that this pesticide had been removed
>from the market in 1992 in response to the eagle deaths -- the result of
efforts by wildlife groups, Virginia state regulators, and the manufacturer.
Note also how many environmental writers lump DDT and PCBs with modern
pesticides. We know that PCBs are some of the most virulent chemical
mutagens and have major impacts on wildlife and ecosystems; no one can defend
their environmental safety. But PCBs were never used as farm chemicals. We
banned DDT because it might have been a culprit in raptor population
declines. Our modern pesticide compounds are far safer than these chemicals,
and there is no scientific or policy justification for lumping them together.
Human Health: Obviously we don’t want farming sustainability at the cost of
human health. However, our pesticides are getting safer and safer, for
people as well as wildlife. Farmers once used lead arsenate, mercury, copper
sulfate and elemental sulfur to protect their crops. Many organic producers
still use copper sulfate and elemental sulfur. These chemicals adversely
affect plant health and, possibly, yields. They also persist in the
environment for relatively long periods and may actually offer more health
risks to humans than modern pesticides.
Mainstream farmers are now using compounds which are targeted to specific
pests and pest physiologies and are, therefore, safer to other organisms.
(For example, most herbicides target enzymes specific to target weed
species.) These compounds, because of their specificity, are also effective
at lower and lower dosages. Most now degrade rapidly in sunlight or under
microbial activity. The already low risks to humans are decreased on three
fronts: specificity to target organisms, decreased amounts used and
decreasing persistence in the environment.
Herbicides are the only category of pesticide in which the quantity used has
increased significantly in recent decades. The revolution created by
conservation tillage practices is mainly responsible, and conservation
tillage is delivering enormous environmental gains. We are accepting tiny,
theoretical risks from herbicide traces in our ground and surface water and
getting huge reductions in soil erosion. In addition, herbicide use per acre
actually declines under continuous conservation tillage as weed pressures are
reduced.
Pesticides Protect Against Cancer
We use chemicals to prevent losses to crops but we also use them to make our
food supply safer from the natural fungal and bacterial toxins which would
otherwise pose a risk to our health. In their zeal to eliminate pesticides
>from farming, extremists fail to acknowledge and warn the public about the
danger of grains and oilseeds contaminated by natural toxins. The Food and
Agriculture Organization of the United Nations estimates that 25 percent of
the worlds grains and oilseeds are dangerously contaminated with toxins.
True, we can screen for these toxins and not utilize the foods contaminated
by them, but extensive testing is costly and making up for the loss of
contaminated grains only adds to the already high burdens placed on
agriculture.
Chemicals also make fruits and vegetables, our strongest weapon against
cancer, cheaper and available for more of the year. Five servings of fruit
and vegetables per day will cut a person’s cancer risk by 50 percent,
dwarfing any theoretical cancer risk from pesticide residues.
Health risks from agrichemicals have been proven negligible. (Note:
consumer health risks, or chronic low exposures, must be separated from
acute toxic exposures to farmers and applicators from accidents and
mishandling.) According to the American Council on Science and Health,
recent increases in cancer are due almost entirely to tobacco, diet, alcohol,
AIDS, and sun tanning. Ironically, better detection methods have also
created the appearance of sudden increases in some cancers, such as breast
and prostate cancer.
Two of the world’s top cancer experts (Sir Richard Doll and Dr. Robert Peto
of Oxford University) were retained by the U.S. Congress to assess U.S.
environmental cancer risk. They concluded, “The occurrence of pesticides as
dietary pollutants seems unimportant. There has been no increase in the
incidence of liver tumors in developed countries since the long-lasting
pesticides were introduced. Yet liver tumors are the most common form of
cancer found in animal-based toxicological studies.” The American Council
on Science and Health put it more bluntly, “ ‘Chemicals’ in food and the
environment do not have significant impact on overall cancer risk in the
U.S.”
John Graham, founding director of the Harvard Center for Risk Analysis,
summed up the human health risk from pesticides when he noted that the U.S.
regulatory safety standard for pesticide residues is no more than one
additional theoretical cancer per million people, yet a person is 5 times
more likely than that to be killed while standing on the ground by a crashing
airplane!
Environmental and Field Quality Issues
Soil Quality
Although conservation tillage and no-till are practical solutions to soil
erosion (until now farming’s biggest sustainability problem), some critics of
high-yield farming have suggested new “problems” associated with modern
farming systems.
One of the primary issues they have raised is soil quality. John Haberern
and Anthony Rodale, of the Rodale Institute, phrased it in lurid, emotional
language: “The soil provides us with life. The quality of that life depends
on the quality of the soil itself .... If we feed the soil, the soil will
feed us. It’s nature’s way.” They see pesticides and even chemical
fertilizers as contrary to this goal and contend chemical use must be reduced
or eliminated.
But fertilizers -- plant nutrients -- are essential to maintaining and
restoring soil fertility, structure and organic matter content. Fertilizers
allow plants to produce more crop and crop residues, and crop residues are
the critical factor in building the content of soil organic matter in our
fields. Long-term studies have shown that soil organic carbon and nitrogen
levels are highest when we combine conservation tillage, crop rotation, and
adequate fertilizer.
Plants absorb all nitrogen fertilizers in an inorganic form regardless of
whether the nitrogen comes from organic or inorganic sources. What this
means is that organic nitrogen fertilizers, such as manures, have no
advantage over synthetic nitrogen from the plants’ perspective. Currently,
virtually all of the world’s nitrogen for synthetic fertilizer is extracted
literally from the air, which is 78% nitrogen gas. It is an entirely
sustainable practice.
More importantly, the world doesn’t have enough organic fertilizers to meet
current fertilizer needs, let alone tripling for the future. Many claim that
we’re currently wasting large quantities of organic material which could be
used on our fields. But global plant nutrient needs are huge. All of the
urban sewage sludge in the U.S. equals only 2 percent of the nitrogen
currently being applied in the form of commercial fertilizers in the U.S.
If we wasted nothing, ignoring recovery and transport costs and potential
heavy metals contamination (a chronic problem with urban sewage sludge), we
would still be roughly 70 percent short of the nitrogen fertilizer needed to
sustain current levels of production.
Organic fertilizers are produced at a heavy cost -- in land required for
pasture or green manure crops. Because of this land requirement, synthetic
nitrogen fertilizers are the only practical way to maintain soil fertility on
the majority of the world’s fields.
What about pesticides? Are they degrading the quality of our soils and
undermining agriculture’s sustainability? Evidence from long term field
studies using pesticides says not. The productivity of the fields continues
to increase as long as the soil structure and quality remains high, and these
factors are most affected by tillage and nutrient management practices.
Although soil quality is important to efficient crop production, the goal of
healthy soil is no end in itself. It is important only as it helps sustain
high crop yields. So far, there is little evidence that the quality of the
soil is degrading past a critical point in the First World. In fact,
herbicide-based low-till systems are now improving soil quality without the
animal wastes or added plant manures which are so land and resource-costly.
Soil Degradation
Soil degradation has been cited as another reason that current practices in
farming are unsustainable. These problems include waterlogging,
salinization, nutrient depletion and soil compaction. While there are lands
affected by these problems, these are localized, manageable problems with
limited global impact.
Nutrient depletion is caused by crop production without adequate
fertilization. All fields must be fertilized to replace nutrients which are
removed in the harvested crops. Nutrient deficiencies are manageable simply
through appropriate fertilization. Soil testing for nutrient presence and
availability is relatively inexpensive.
Soil compaction occurs when external pressure from farm implements
(tractors, harvesters, etc.) causes large soil pores to collapse resulting in
slow water infiltration, poor drainage, and poorly aerated soils which limit
root growth and nutrient uptake. Solving soil compaction involves
appropriate management practices and equipment. These can include no-till
and conservation tillage, deep ripping to break up hard pans where they occur
under the soil surface, permanent tracks for equipment to run on, and
low-pressure tires, multiple axles and tracked equipment which reduce the
pressure on the soil and prevent compaction from reoccurring.
Salinization and waterlogging result from irrigation and over-irrigation of
cropland, particularly in drier areas, and areas with poor drainage.
Salinization can also be caused by poor quality groundwater. It occurs when
excess water evaporates, leaving behind salts which concentrate in the top
soil. Although salinization and waterlogging are separate phenomena, they
are often linked in susceptible areas.
Prevention should be our primary goal for salinization and waterlogging
problems and is often straight-forward: more frequent light irrigation,
higher soil moisture regimes and conjunctive use of surface and groundwater.
The overuse of water is the biggest contributor to the problem. (flood
irrigation used by traditional farmers is also one of the major culprits)
Ownership of water rights and real-cost pricing of water resources would
encourage conservation and help avoid overuse.
There are after-the-fact solutions to existing salinization and water
logging, such as leaching with water and simultaneous lowering of the water
table. However, these are relatively expensive compared to prevention.
Runoff of Nutrients and Chemicals
Runoff of nutrients and chemicals into surface waters has become a prominent
issue as efforts to restore the quality of our rivers and streams have
progressed past the obvious sources of point-source pollution such as
factories, paper mills, etc. The concerns include such plant nutrients as
nitrogen and phosphorus as well as pesticides. But runoff from our fields
and pastures is another manageable problem. There is nothing inherent in our
production systems that demand the occurrence of chemical or nutrient runoff.
Chemicals which runoff are losses to the farmer. Indeed, organic farming
and alternative systems can be just as guilty as conventional systems in
poorly managing runoff.
Preventative solutions include avoiding excess fertilizer and pesticide
applications, timing applications for sensitivity to local conditions
(especially rainstorms), establishing appropriate filter strips, and building
animal waste lagoons and other interception technologies. Our biggest asset
for controlling runoff is increased use of no-till and other conservation
tillage practices which create soil structure conditions where runoff is
radically reduced or eliminated. So far, organic farmers have not utilized
these techniques.
American farmers are also beginning to make broad use of precision farming
to reduce chemical and nutrient runoff. Precision farming uses global
positioning satellites, intensive soil sampling and microprocessors to manage
land square yard by square yard rather than by 80 or 160-acre blocks. The
computer can modify seeding and chemical application rates many times each
second, depending on soil type, slope, plant population, cropping history,
hydrology, nearness to waterways and any other significant factor. There is
no need to apply more than the crop will use, nor any need to accept lower
yields.
It is increasingly likely that the world will seek sustainability through
high yields within a system of conservation tillage and precision
application.
Resource Depletion
Extremists have cited agriculture’s dependence on non-renewable resources as
evidence of the unsustainability of current approaches. However, this is a
harshly over-simplified indictment of high-yield agriculture. Agriculture’s
current non-renewable resource dependence is relatively small and only two
inputs seem to raise sustainability issues -- petroleum and phosphorus.
Petroleum: At the moment, petroleum is a cheap and readily available carbon
and energy source. The percent of U.S. petroleum used in farming is tiny.
Agriculture currently accounts for only 2% of total U.S. energy consumption
for direct energy use and the manufacturing and transport of agrichemicals
and fertilizers. Moreover, agriculture will use whatever energy system the
rest of our industries and homes use. When the U.S. was horse powered, so
was agriculture. When the change from fossil fuels to electricity, hydrogen,
fusion, etc. occurs, agriculture will change too.
There is no sound rationale for forcing agriculture to change its energy
system ahead of the rest of the economy. Agriculture could, but it would
ultimately hurt our sustainability in other areas. For example, if we
removed a percentage of crop residues for direct energy production (for
example, by burning for electricity production), the extra land we would need
and the reduced levels of residues on fields (which are needed to maintain
soil quality and structure) would undermine any environmental benefits. It
is pure folly to use our food producing industry for energy experimentation.
SIDENOTE: In 1930 it took 30 million acres to produce the feed for farming’s
draft animals. How much wildlife habitat are we willing to sacrifice for
draft animal pastures now?
Phosphorus: Some individuals are claiming that the world is short of
phosphorus rock ore reserves. Phosphorus is a major plant nutrient, and
virtually all of the world’s phosphorus consumption is in agricultural feeds
and fertilizers. Phosphorous is less abundant than most of the other natural
elements. Some argue that this resource is very limited and predict we will
exhaust our mineable ore reserves in a relatively short time. For example,
Herring and Fantel predict we will have depleted known phosphorus ore
reserves in a short 100 years. A closer look, however, reveals several
major flaws in their analysis: First, they underestimate known phosphate ore
reserves. Second, they assume continuous exponential growth in demand, far
beyond the tripling of world farm output that is likely. Third, they offer
ridiculous population growth estimates of between 58 billion (lowest
estimate) and 821 billion people by 2150.
Predictions of resource depletion dates are always highly suspect, because
of economics and human nature. First, mining companies don’t admit to having
very large reserves of ore. Demonstrated ore reserves are taxed assets --
the less one demonstrates, the lower the taxes. And as more reserves are
demonstrated, the value of known reserves falls. Therefore, the incentives
are to underestimate. Finally, when prices rise, mining companies can afford
to mine lower grade ores; the amount of economically “mineable” reserves
thus increases.
Reasonable estimates of phosphate ore reserves extend at least 250 years,
and that does not include vast reserves of lower-grade ores which could
become available with future mining technology. The U.S., as one example,
has phosphate concentrations in 28 States, but only four large fields are
currently competitive. Biological extraction systems are one of the likely
prospects for producing future large quantities of affordable phosphorus from
the world’s extensive deposits.
Social Engineering
The “sustainable agriculture” movement has become a haven for social
activists who see it as a new, fashionable justification for their visions of
reshaping society. Two prominent issues are 1) saving the small family farm
and 2) “community food security.” To further these agendas, they are
attempting to change national farm policy.
The Small Family Farm
What is a family farm? The family farm is a term in constant redefinition.
The federal government defines a farm as “any agricultural enterprise which
generates $1,000 or more from sales of agricultural commodities or food
products.” But technology has allowed one man to farm more and more acres.
At the same time the value of the off-farm job with which farming must
compete has risen. As a result, average farm size has steadily increased.
The average farm size in 1950 was a little over 200 acres; today it is
approaching 500 acres. This is the average for all farms. If one were to
survey only those farms where a majority of the household income was derived
>from the farm, the average size would be even greater.
Accordingly, the number of farms has declined over this period, from 5.5
million in 1950 to 2.1 million today.
The activists see these trends as a policy failure. However, it is unlikely
that national farm policy can preserve traditional and possibly inefficient
farm structures, or make people want to live in less hospitable areas.
To date, government programs and intervention have probably worsened the
small-farm problem. Farm programs have contributed to larger farms and
destabilization of rural communities by supporting debt-leveraged neighbor
buy-outs with price supports and payments. The federal subsidies let the
high-tech farmer win twice -- with greater sales and bigger payments.
Without the certainty of Federal price supports, fewer big farmers would
have gotten loans to buy out their smaller neighbors.
Government farm programs have also played a major role in rural non-farm
depopulation through land setaside programs. One study estimates that land
set-aside programs have cut the rural non-farm population by 30 percent,
because of the crops not grown, transported or processed, reduced machinery
usage, and the impacts on supporting businesses and services.
But should preserving the small family farm even be our goal? The family
farm is and continues to be the success model around the world. Virtually
all of America’s field crops and most of our meat come from family owned and
operated farms. Many people fear that as farm size increases, the number of
farmers decreases, and at some point the population density falls below what
is needed to support the nearby rural community. The real question for rural
society, however, is not farm size but rural community viability. What needs
to be pointed out is that farming is not the biggest element of the economic
base of most rural communities. Three times as many basic industry jobs in
rural counties are in manufacturing as in agriculture, forestry and fisheries
combined. Only 17 percent of the nation’s counties are farming dependent
(deriving at least 20 percent of income from farming.)
Large farms produce the vast majority of agricultural products because
larger farms are 1) bigger 2) often more efficient and 3) often have higher
yields. Worse, small farms by their very nature don’t produce much income.
People could still live on 80-acre subsistence farms in the Midwest,
producing their own food, raising their own draft horses and reading books
>from the public library by the light of kerosene lamps. Such farms would
give us a higher rural population density, and they would certainly reinforce
the old rural values of hard work and duty to the farm and family. However,
very few people choose to live that way. Those who do don’t contribute much
to feeding and clothing the rest of us.
Indeed, the trend toward larger farms and the various strategies toward
production are realities that are difficult to overcome. Vertical
integration may ultimately dominate in the hog and poultry industries by
being more cost effective and competitive. It may also offer its labor force
better incentives to stay in rural areas through financial opportunities and
more comfortable lifestyles. (Many families are currently supporting an
attractive rural lifestyle with contract poultry production.) It is
impossible to dis-invent these strategies. Making them more costly through
farm policies directed at preserving the “small family farm” would hamper
long-term U.S. competitiveness -- very possibly making our rural communities
less viable in the future. (Iowa has already lost hog market share to other
states because of constraints on farm structure.)
Currently most “small family farms” are being supported through off-farm
income. Only 15 % of all farms derive more income from farm than off-farm
sources. This is an economic reality. The most important insurance for the
“small family farm” and for rural communities is adequate numbers of off-farm
jobs.
In terms of rural community viability, the two most promising potentials are
1) job decentralization and 2) increased agricultural exports (including
processed products) for newly-industrializing countries in Asia.
Job decentralization is being driven by fiber optics, fax, and internet
communication. Many people can now take their jobs where they want to live.
The communications revolution has ended rural America’s isolation, and the
exodus could now be reversed for most rural communities.
Agricultural export opportunities offer enormous potential for rural
communities. The income from increased commodity sales would benefit the
entire community. Value-added processed exports mean more jobs in and
support of processing facilities. By their nature, most of these jobs are in
or adjacent to rural areas. An extra $50-75 billion a year in income from
exports, most of it going to farms and rural-oriented agribusiness, would
mean more in re