Robert Wyeth Independent Consultant West Seneca, NY What is a Pescide A pesticide is any substance or mixture of substances intended for: — Preventing — Destroying — Repelling, or — Mitigating any pest Refers to insecticides, herbicides, fungicides and various other substances used to control pests (insects, animals, unwanted plants, fungi and microorganisms). Types of Pescides Chemical pesticides — Carbamate pesticides — Organochlorine insecticides — Pyrethroid pesticides Biopesticides — Microbial pesticides — Plant incorporated protectants (PIP) — Biochemical pesticides More — Algicides — Miticides — Antifouling agents — Mollusicides — Antimicrobials — Nematicides — Attractants — Pheromones — Disinfectants — Repellents — Biocides — Rodenticides — Disinfectants — Defoliants — fumigants — Dessicants — Herbicides — Insect growth regulators — Insecticides — Plant growth regulators World and U.S. Amount of Pesticide Active Ingredient Used By Pesticide Type, 2006 and 2007 Estimates Year Type World Market U.S. Market U.S. % of World Mil lbs % Mil lbs % Market 2006 Herbicides (1) 2,018 39% 498 44% 25% Insecticides 955 18% 99 9% 10% Fungicides 519 10% 73 6% 14% Other (2) 1,705 33% 457 41% 27% Total 5,197 100% 1,127 100% 22% 2007 Herbicides (1) 2,096 40% 531 47% 25% Insecticides 892 17% 93 8% 10% Fungicides 518 10% 70 6% 14% Other (2) 1,705 33% 439 39% 26% Total 5,211 100% 1,133 100% 22%

Note: Totals may not add due to rounding. Does not include wood preservatives, specialty biocides, and chlorine/hypochlorites. (1) “Herbicides” include herbicides and plant growth regulators. (2) “Other” includes nematicides, fumigants, and other miscellaneous conventional pesticides, and other chemicals used as pesticides such as sulfur, petroleum oil, and sulfuric acid.

Source: EPA estimates based on Croplife America annual surveys, USDA/NASS, and EPA proprietary data. Most Commonly Used Conventional Pesticide Active Ingredients, Agricultural Market Sector, 2007, 2005, and 2003Estimates (Ranked by Range in Millions of Pounds of Active Ingredient) 2007 2005 2003 Active Ingredient Type Rank MM of lbs Rank MM of lbs Rank MM of lbs Glyphosate Herbicide 1 180-185 1 155-160 1 128-133 Atrazine Herbicide 2 73-78 2 70-75 2 75-80 Metham Sodium Fumigant 3 50-55 3 39-44 3 45-50 Metolachlor Herbicide 4 30-35 5 27-32 6 28-33 Acetochlor Herbicide 5 28-33 6 26-31 5 30-35 Dichloropropene Fumigant 6 27-32 4 30-35 7 20-24 2,4-D Herbicide 7 25-29 7 24-28 4 30-35 Methyl Bromide Fumigant 8 11-15 8 12-16 8 13-17 Chloropicrin Fumigant 9 9-11 10 9-12 9 9-12 Pendimethalin Herbicide 10 7-9 9 9-12 10 9-12 Plant Growth Ethephon Regulator 11 7-9 11 8-10 15 6-7

Chlorothalonil Fungicide 12 7-9 13 7-9 14 7-9 Metam Potassium Fumigant 13 7-9 20 4-6 20 4-6 Chlorpyrifos Insecticide 14 7-9 15 6-8 13 7-9 Copper Hydroxide Fungicide 15 6-8 12 8-10 12 7-9 Simazine Herbicide 16 5-7 17 5-7 17 6-7 Trifluralin Herbicide 17 5-7 14 7-9 11 8-10 Propanil Herbicide 18 4-6 18 4-6 18 5-7 Mancozeb Fungicide 19 4-6 16 6-8 16 6-7 Aldicarb Insecticide 20 3-4 21 3-5 25 4-6 Regulatory Perspecve EPA regulates the use of pesticides under the authority of two federal statutes: the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) and the Federal Food, Drug and Cosmetic Act (FFDCA).

Analysis for pesticides is performed consistent EPA methods for air water and soil, the FDA Pesticide Analysis Manual (PAM) and AOAC methods. NIOSH and OSHA have methods for pesticides.

Manufacturers are also required to submit analytical test methods as a part of their required registration.

Methods are available from EPA’s Office of Pesticide Programs (OPP) Analytical and Environmental Chemistry Laboratories Focus on Top 10 1. Glyphosate 2. Atrazine 3. Metham Sodium 4. Metolachlor 5. Acetochlor 6. Dichloropropene 7. 2,4-D 8. Methyl Bromide 9. Chloropicrin 10. Pendimethalin

Glyphosate [N-(phosphonomethyl)-glycine]is a non-selective herbicide that works by stopping the plant from producing an enzyme it needs to make protein for proper growth. Glyphosate is widely used in agriculture, industrial weed control, forestry, and in outdoor residential applications. It comes in a number of chemical forms but most of the formulated products contain the isopropylamine salt. The toxicity of glyphosate is influenced by the surfactant in the product. Round-up by Monsanto is an example glyphosate.

Glyphosate Analysis Glyphosate is a post emergent herbicide which rapidly degrades in the environment. Due to its heat sensitivity and polar nature, amongst other chemical properties, analysis methods utilize ion/liquid chromatography. Methods also include aminomethylphosphonic acid (a primarily degradation product) and glufosinate (a compound simliar to glyphosate in chemical structure and use). Glyphosate Methods — EPA Method 547 LC/Fluorescene with post column derivitatization (water) — USGS 01-454 LC/MS with SPE (water) — OSHA PV2067 LC/UV after deriviatization (air) — Numerous literature articles virtually all liquid chromatography

ATRAZINE

Atrazine [2-chloro-4-(ethylamino)-6-isopropylamino) s- triazine] is widely used herbicide for control of broadleaf and grassy weeds. Effective in 1993, its uses were greatly restricted. Analysis for Atrazine, with some exceptions, is multi- component analysis. Due to ecological concerns over Atrazines and other Trazines, numerous methodologies are available for use in numerous matricies. Atrazine Methods Analyses are approved for use with GC (ECD or NPD detectors), GC/MS, Immunoassay and High Resolution GC/MS: • EPA Methods 505, 507, 508.1, 525.2, 527 (with SPE), 1699 and 8141B with derivitization • EPA Method 4670 (quantitative immunoassay) • USGS Methods O-1121-9, O-2060-01, O-3106-93, and O-1126-95 • ASTM Method D5475

Metham Sodium (or Potassium) (methyldithiocarbamate salts)

Metham (or Metam) sodium is a soil fumigant used as a pescide, herbicide, and fungicide. It is one of the most widely used pescides in the United States, with approximately 50 million pounds used in 2007. Metham sodium is the sodium salt of methyldithiocarbamate. Other names include Carbathion, Carbathione, carbothion and metham sodium (or the potassium salt). Upon exposure to the environment, metam sodium decomposes to form methyl isocyanate. Metham Sodium Methods No specific methods are currently referenced/available for analysis of Metham Sodium in environmental or related matrices. Methods suggested based upon ability to analyze other dithiocarbamate type constituents include: — EPA 630 and 630.1 (no compound specific), 8270D, 531.1, 531.2, and 8321 (LC/UV or LC/MS) — USGS O-1126-95, O-1131-95 and O-1433-01

Metolachlor

Metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-2 methoxy-1- methyl) acetamide]is widely used as an herbicide. It is a derivave of aniline and is a member of the chloroacetanilide herbicides. It is highly effecve toward grasses but its applicaon is also controversial. Metolachlor has been detected in ground and surface waters throughout the U.S. It is classified as a Category C pescide by the US EPA which indicates limited evidence of carcinogenicity. Evidence of the bioaccumulaon of metolachlor in edible species of fish as well as its adverse effect on the growth and development raise concerns on its effects on human health.

Metolachlor Methods Numerous EPA are available fro Metolachlor including: — Method 507 GC/NPD — Method 508.1GC/ECD with LSE (C-18) — Method 525.2 GC/MS with LSE — Method 551.1 GC/ECD micro L/L — Method 535 LC/MS-MS SPE (particularly applicable for degrades) Other available methods include: — ASTM D-5475 — USGC O-3106-93 GC/NPD SPE — USGS O-1126-95 GC/MS SPE — USGS O-1433-01 GC/MS SPE — USGS O-1121-91 GC/MS SPE A number of immunoassay techniques also available.

ACETOCHLOR

In the US, Acetochlor was registered by the EPA as a direct substute for many herbicides of known concern. The EPA imposed several restricons and condions on the use of acetochlor. It is ulized as a pre-emergence applicaon or for pre- planng applicaon with soil incorporaon parcularly for corn. It's the main acve ingredient in Acenit, Keystone, Guardian, Harness, Relay, Sacemid, Surpass, Top-Hand, Trophy and Winner. It is used to control weeds in corn, and is parcularly useful as a replacement for Atrazine for many weeds.

Acetochlor Methods Numerous EPA methods are available for analysis of Acetochlor including: — Method 535 LC/MS-MS with SPE — Method 526 GC/MS with SPE — Method 525.2 C/MS with LSE USGS also lists Acetochlor in methods: — O-1126-95, -01 GC/MS with SPE — O-1433-01 GC/MS with SPE — O-2002-01 GC/MS with SPE A number of immunoassay techniques are also available Rounding out the Top 10 #6 Dicloropropene Ø Soil fumigant (toline) amongst other uses, Method 1624 most prominent method of analysis. Numerous other methods also available.

#7 2,4-D (2,4-dichlorophenoxyacetic acid) Ø common systemic pesticide/herbicide used in the control of broadleaf weeds. It is one of the most widely used herbicides in the world, and is the third most commonly used herbicide in North America.[It is a synthetic auxin (plant hormone). It was a major ingredient in Agent Orange alongside its chemically similar relative, 2,4,5-T ,4-D. Ø Most prominent methods of analysis EPA 515.1 and 8151A, numerous methods including immunoassay also available

#8 Methyl Bromide (bromomethane) Ø Until its production and use was curtailed by the Montreal Protocol, bromomethane was widely applied as a soil sterilant mainly for production of seed but also for some crops such as strawberries and almonds . In commercial large-scale monoculture seed production unlike crop production, it was of vital importance to avoid contaminating the crop other herbicides. Ø Most prominent methods of analysis EPA 524.2, 8021, 624, 1624, and 8260B, numerous methods including immunoassay also available

#9 Chloropicrin [trichloro(nitro)propane] Ø Chloropicrin is used as a fumigant to control pests found in the soil. Although less common, it can be used as a poison for vertebrates, such as rabbits. Chloropicrin is commonly used in combination with other fumigants, such as methyl bromide, for increased potency and as a warning agent. Chloropicrin has been used in chemical warfare. Ø The only analytical method including chloropicrin is EPA Method 551.1 (GC/ECD with L/L)

#10 Pendimethalin Ø Herbicide used in pre-emergence and post-emergence applications to control annual grasses and certain broadleaf weeds which interfere with growth, development, yield and quality of agricultural and horticultural crops . It protects crops like wheat, corn, soybeans potatoes, cabbage, peas, carrots and asparagus. Ø No methods are cited for pendimethalin but should be amenable to GC/NP or LC/MS technologies upon extraction. Manufacture method should be available from registration. Environmental Fate and Ecotoxicology

Equally as important from a fate and toxicology perspective is the fate of these pesticides in the environment and what are their degradation products.

The advantage of many of these pesticides relative to historically used materials is their short half-life in the environment.

Studies, primarily by the manufacturer, provided upon registration, pr esent data on fate and ecotoxicology. A compilation of information (the Ecotoxicity Database and the Pesticide Fate Database) is managed by the EPA Office of Pesticide Programs and can be assessed through their offices. Commercial Tesng Industry Preparedness

While most of the currently used pesticides have references to applicable methodologies that should be directly useable or readily adaptable for use, few commercial laboratories are conducting these analysis today. One significant reason to the commercial labs is lack of demand. But this is likely to change!

Pescides in the Commercial Lab Generally prepared to respond to requests for: — Organochlorine pesticides — Organophoshorus pesticides — Herbicides

Almost always by GC (with selective detectors) or GC/ MS.

Many labs still do not utilize or even have LC on-line let alone LC/MS-MS. Future of Pescide Analysis — Steady but decreasing demand for traditional long half-life pesticides (i.e.; DDT, lindane, etc) — Increasing demand and more competition for pesticides in use today — Labs will require capital for LC and/or LC/ MS-MS equipment — Labs will have to develop and become accredited for these new methods and analytes