Group 1 - Article: The Pesticide Must Evolve

Abstract (to be written by Emily Ferguson)


Every day you eat them, without knowing it, and will continue to do so unwillingly for the foreseeable future. Pesticides are a part of everyday life, on every fruit and vegetable in the market, with the exception of a very few. They are a necessary part of farming, as they are the only tool against major crop loss caused by nature itself. The main types of pesticides are chemical pesticides, bio-pesticides, and antimicrobials. In short, chemical pesticides are synthetic chemicals that typically attack the nervous system of small animals and bugs, bio-pesticides serve the same purpose but are derived from organic material, and finally antimicrobials are either synthetic or natural chemicals that are used to kill viruses, be it ones harmful to the plants or for human consumption. They are a necessary evil in short.

Since man stopped being nomadic it started to see how tough it is when you have to fight off worms in your apples, snails in your corn, and beetles on your lettuce. We use pesticides to curtail those problems and minimize crop loss, and sometimes this comes at a cost. Prolonged exposure to pesticides can lead to everything from simple skin irritation to, in extreme cases death. Long term exposure has been shown to even cause infertility and cancer. Most overexposure cases though happen in developing countries, where handling and usage of pesticides is much more liberal.

Pesticides also have adverse effects on the environment, to varying degrees. When pesticides are sprayed from a crop-duster for instance, pesticide drift occurs and often times is carried by the wind to areas where it was not intended, affecting the plants and animals in that ecosystem. Pesticides also soak into the soil and affect everything from nitrogen fixation, which is necessary for essentially all life on the planet, to leeching into the water table. The latter is a major concern as it often isn’t immediately noticed and takes some time to reach the underwater aquifers on earth. This can lead to a litany of problems for human health as well as all biological life.

Methyl Bromide and Methyl Iodide Background

Methyl bromide, also known as bromomethane, is an organobromine compound with chemical formula of CH3Br. When it is in a pure solution it is colorless and odorless. It is naturally produced, and extensively through industrial usage. It is easily produced by reacting methanol and hydrogen bromide. Methyl iodide was first approved to be used as a replacement for methyl bromide, which is a soil fumigant that is used to harm the ozone layer. This pesticide is mainly used for farmers that grow strawberries.

Effects of contact:

- Severe irritation of lower respiratory tract.
- Central nervous system depression and convulsions.
- Pulmonary edema, hemorrhage, and confluent pneumonia.
- Early symptoms of acute poisoning include headache, dizziness, nausea, vomiting, tremor,
slurred speech, and ataxia,
- Severe poisoning exhibits myoclonic and generalized tonic clonic seizures, ataxia, muscle
weakness, tremors, behavioral disturbances and diminished reflexes.
- Skin contact causes severe burning, itching, blister formation, necrosis, slurred speech, and kidney problems
-late-term miscarriages
-thyroid disease
-neurological problems

It was world widely used for fumigation purposes in all kinds of pesticides, such as fumigant, herbicide, insecticide and nematicide. However, because it is one of the substances that depletes the ozone layer, it was planned to be internationally banned by 2000 by the Montreal Protocol. As U.S. faced problems such as lack of cheaper alternative pesticides, the deadline had been extended to January 2008 between farmers. Right now the use of methyl bromide is 100% phased out except for allowable exemptions such as critical use exemptions agreed to by the Montreal Protocol Parties.

As of 2007 an alternative source of methyl bromide, methyl iodide was introduced by Arysta Life Science Company. The company was awarded with 2009 Stratospheric Ozone Protection Award.

Methyl iodide is an organoiodide chemical compound, also known as iodomethane or mel. It is colorless and a liquid that evaporates easily. It can be industrially produced in multiple ways from two main sources of iodide, phosphorus triiodide and potassium iodide.

The biological effects that it had towards human were worse than that of methyl bromide. A study on rats showed that when methyl iodide was injected or inhaled, lung tumors developed and lead to cancer. Another experiment on mice showed that exposure to methyl iodide resulted in narcosis, lung congestion, and liver, kidney and stomach damage. The damage to liver, kidney and stomach included DNA adducts through closed system inhalation. An experiment on bacteria and yeast showed induction of DNA damage, which indicates carcinogenicity. Methyl iodide Workers affected by non-fatal poisoning showed neurological symptoms such as visual and psychological disturbances, vertigo and weakness. Other symptoms when exposed by methods of inhalation, skin absorption, ingestion, and eye contact include nausea, vomiting, dizziness, ataxia, slurred speech and dermatitis.

Methyl iodide’s usage is widely spread globally as all kinds of pesticide such as fumigant, herbicide, insecticide and nematicide. It has replaced methyl bromide for reduced contamination of environmental conditions. The replacement diminished the main reason for banning methyl bromide which was depleting the ozone layer. However, the biological risks to human have increased in both acute and chronicle ways. EPA (Environmental Protection Agency) has not classified methyl iodide as a threat of potential carcinogenicity. Also, International Agency for Research on Cancer classified that methyl iodide is not carcinogenic to humans. Despite the fact that many studies show that methyl iodide carries carcinogenic risks, the degree of carcinogenicity does not reach the agencies’ guide lines of classifying it as carcinogenic to human. However, Washington and New York states have not yet approved its usage because of its highly toxic nature. They are still in the process of doing their own risk assessment. This pesticide has the biggest threat to farmworkers but people that live near farms are at a greater risk.

Methyl Iodide Approval and Usage

Methyl iodide was initially approved by the Environmental Protection Agency in October of 2007 as a pesticide to be used in replacement of Methyl Bromide(1) because it does not effect our ozone layer as much as Methyl Bromide does(11). It is the best pesticide controlled today by the U.S. Environmental Protection Agency(11). It is now registered as a pesticide on the federal level for agricultural use in 47 other states(2). Legislation in California like other states requires that new pesticides must be subjected to secondary review despite federal approval(3). On December 1st, 2010 the California Department of Pesticide Regulation (DPR) approved methyl iodide for use as a soil fumigant pesticide in agriculture(1). New York and Washington have declined to approve its use as a pesticide on the state level(1).

The pesticide is approved for, and used by farmers of strawberries, tomatoes, nuts, peppers, eggplant and other crops mainly in southeastern states(2). It's used to control weeds, fungi and insects that are in the soil (11.) It is produced by the Tokyo-based Corporation Arysta LifeScience, which markets the product under the name Midas(2). The strawberry farms in California are currently their largest marketplace. The California strawberry industry generates an annual value of over $1.6 billion(2). Aside from the strawberry crops, Arysta LifeScience also stands to gain significant profits from the pesticides use in Central Valley's nut orchards as well as fresh flower nurseries along the coast in Ventura and San Diego counties(2). It has been used in Southeastern parts of the US on 15,00 acres of land for three years(11).

Over the past several decades Methyl Bromide was the primary pesticide used on California strawberry crops. This was true until the Montreal Protocol international climate treaty banned its use. Following the ban the chemical industry needed to quickly find a feasible alternative(3). This led to the development and approval of Methyl Iodide. Many Californians accepted the pesticide as an appropriate alternative. Supporters of its use argue that it can be used safely through regulation and proper procedure despite it being listed as a carcinogen under California’s Proposition 65 statute and recognized as a highly toxic chemical(6).

Advocates of methyl iodide insist on its safety, since permits and strict safety guidelines must be enforced and followed. It has been argued by regulators that, "Methyl iodide can be used safely under our tough restrictions by only highly trained applicators at times, places and specific conditions approved by the county agricultural commissioners."(2) Other precautions for its use in California include buffer zones where the chemical cannot be applied as well as the implementation of “special tarps to keep fumes from escaping the soil.”(2) According to the New York Times, “California has provisionally approved methyl iodide and will issue a final decision after the public comment period ends June 29.”(3)

The provisional approval of Methyl iodide after latest review has led to increased controversy and opposition. It has been found that the chemical is less harmful to the ozone, but poses more potential health hazards to humans(3). In December of 2010 a lawsuit was filed in the Alameda Superior Court by Earthjustice and California Rural Legal Assistance, Inc. in effort to stop the pesticide’s use(7). A senior scientist with the Natural Resource Defense Council named Gina Solomon stated, “Use of methyl iodide instead of methyl bromide creates a Sophie's choice: Trading off protection of the ozone layer against serious risk to groundwater resources; trading off a reduction in skin cancers for an increase in thyroid and other cancers.”(5) California legislators have also expressed their opposition to methyl iodides use. On April 4th, 2011 Speaker of the Assembly John Pérez, submitted a letter to the Environmental Protection Agency requesting policymakers to “suspend and cancel all uses of iodomethane (methyl iodide) in the United States…”(1) As a result of such controversy further research has been conducted in effort to find alternatives to Methyl Bromide that are safer to both the ozone and human health than methyl iodide.

The EPA has a petition going around to remove methyl iodide from the grocery stores and farms(9).

Methyl Iodide Alternatives

It has been suggested that the most environmentally sound and effective solution to replacing Methyl Bromide and Iodide might be a combination of treatments instead of a few highly effective/toxic chemicals. This includes both biological controls and chemical options. A chemical alternative that has shown promising results is called Telone C35 and consists of about 60 percent 1,3-dichloropropene and up to 35 percent chloropicrin. The water soluble formulation is also available through the manufacturer Dow AgroSciences LLC, and can be used in drip irrigation systems, which may help reduce risks to workers. Marketable yields of some plots treated with InLine ranged from 95%-110% of those treated with Methyl Bromide(8). Several biological treatment methods are also being considered. Studies have shown that introducing specific microbes to crops after fumigation can be beneficial to growth. The microbes use nutrients that otherwise would be utilized by harmful microbes, and also further contribute to creating conducive conditions for the growth of strawberries(8). There are safer approaches to growing the strawberries such as steaming-oil, spreading mustard seed meal into the soil,or growing the strawberries on raised beds where plants are rooted in ground-up coconut husks or other materials. These alternatives are earth-friendly alternatives(9). Recently studies from the U.S. Department of agriculture recommended using hot molasses on fields(9). Specific pest control alternatives are using resistant cultivars, cultural methods such as crop rotation, the use of cover crops, and physical methods such as soil solarization(10).

Economic Analysis

With most decisions in life, the economic benefits must be weighted. According to Craig Osteen’s article entitled “Methyl Bromide Phaseout”, the average cost of a pound of methyl bromide before reduction occurred was $2.50. This rose to $4.50 per pound shortly before it was completely phased out. Before the phase out, according to the EPA’s website (1995 Pesticide table) the U.S. spent $11 Billion, as a whole, on pesticides in 1995. This number reflects a high usage of methyl bromide, as it was still widely used at this point. In 2007, long after the phase out of methyl bromide, the U.S. spent a staggering $39 Billion on pesticides, a roughly 248% increase. The cost of methyl iodide, according to a quick check of an agriculture website, is roughly $11 per pound. If that number is applied to the numbers for usage in 1995, according to the table earlier, that would equate to a cost increase of 193% for that fiscal year, a staggering sum even when accounting for general inflation. As China is the world leader in pesticide production in today’s world, it is impossible to fully see the profit changes over the years with relation to changes in pesticides used, but knowing common manufacturing techniques, it is easy to compare the productions of methyl iodide to bromide. Methyl bromide is less a synthetic substance and more of a biologically produced product, making it cheap and easy to produce, while methyl iodide is a synthetic substance that does not occur in nature at all, and this is more expensive to produce. With a federally mandated switch to higher cost pesticides, the cost was passed to the consumer.


The usage of synthetic pesticides over the years has stayed the same as a percentage, but it is important to note that pesticides have come leaps and bound from the days of DDT. Science is further pushing the boundaries on synthetics like methyl iodide but it is still safe to say that the future lies in furthering the development of biological, or partly biological. Starting to grow things organically will be something that is evolved in the future. Methyl bromide was on most accounts a success, due to its cost and similar draw backs to products used today, but mostly because it is a naturally occurring substance, all be it in small quantities, by marine organisms. Taking a completely separate route though technologies like the genetic engineering of plants can help curb insect and animal appetite without harm to humans and the earth. Other methods like pheromone placement could be used to keep insects in trap fields, away from the real crops, without any genetic manipulation or hurt to the ecosystem at all. The future in farming once again lies in the hands of scientist, and it is up to them to develop the most effect product with the least harm.

Works Cited


Osteen, Craig. "Methyl Bromide Phaseout Proceeds: Users Request Exemptions."USDA Economic Research Service - Home Page. Amber Waves. Web. 30 June 2011.<>.
Home Page. Amber Waves. Web. 30 June 2011.
"1994-1995 Pesticide Market Estimates: Tables and Charts | Pesticides | US EPA." US Environmental Protection Agency. Web. 01 July 2011. <>.

"2006-2007 Pesticide Market Estimates: Sales | Pesticides | US EPA." US Environmental Protection Agency. Web. 01 July 2011. <>.

Gregory Johnson

I agree that the pesticide must evolve. But I doubt that using synthetic pesticides is any safer than methyl bromide. We have no idea as to the long-term effects of synthetic pesticides. They are like drugs: the effects of drugs are often found after the lab tests, because they are often undetectable at first, and thus we have many drugs introduced into the market and later removed. It cannot be any different with synthetic pesticides.

All chemical or synthetic pesticides should be phased off the market because there is too much risk involved with introducing foreign chemicals to crops and ruining them or hurting people. An example of a pesticide with less risk is BT (bacillus thuringiensis), which is very effective against caterpillars on tomato crops. According to W.S. Cranshaw, BT produces delta-endotoxins which react with the lining of the pest’s digestive system and paralyze it, causing the insect to stop eating and eventually starve to death. BT is a very effective choice, but if bacteria were studied further, more pesticides could be found. Also, genetically-engineered bacteria could prove useful against pests.

Another possible choice as a replacement for pesticides is spiders. Spiders eat common vegetable pests. Dangerous spiders like black widow or brown recluse spiders are not necessary; less harmful breeds like wolf spiders can be used. Though spiders may be scary or unattractive, they do prove their worth by controlling pests. Genetic engineering could further their usefulness.

Work Cited
Cranshaw, W.S.. “Bacillus Thuringiensis.” Colorado State University Extension, Campus
Delivery 4040, Fort Collins, Colorado 80523-4040. December 2008. 1 July
2011. Web.

Marcela Roy

With much speculation revolving around where our food originates, it is difficult to find answers when nearly every product is being linked to some sort of illness or improper production method. Although Methyl Bromide was found to be harmful to both the environment and human health, it seems as if any applicant to plants that isn’t 100% natural is going to eventually have some sort of a negative impact. The use of synthetic pesticides doesn’t appear to be a valid alternative as it may be safer than pesticides such as Methyl Bromide and DDT, but can still have negative affects on health.

The safest alternative to purchasing contaminated produce from the local grocery store is to grow plants at home, if it is possible. Obviously you will not be able to grow the exact produce that you want under most circumstances but you can grow whatever is possible under your own limits. Natural ways of fending off insects is by placing plants near produce that insects do not like. For example, I use marigolds to fend off aphids. Another way of fending them off is spiders, as mentioned above.

Val Komarov

Format editing and revising of the entry. Added a TOC like the other articles.

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