A monthly report on pesticides and related environmental issues
Issue No. 132, February 1997

Open Forum:
In an attempt to promote free and open discussion of issues, The Agrichemical and Environmental News encourages letters and articles with differing views. To include an article, contact: Dr. Catherine Daniels, Food and Environmental Quality Laboratory, 2710 University Drive, Richland, WA 99352-1671, ph: 509-372-7495, fax: 509-372-7491,
E-mail: cdaniels@tricity.wsu.edu

In This Issue

News and Notes Allan Felsot
CDC Suspects Pest Spray Water
for Outbreak of Food Illness
WSCPR Considers
Research Proposals
Officially Unofficial WASS Summarizes
1996 Washington Crops
WSU Pesticide Education One Company's Approach
to Developing a Pesticide
EPA Commitments
Regarding FQPA
IR-4 Food-Use
Research -- 1997
FQPA and Apples Available Reports
FQPA -- The Latest Federal Issues

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News and Notes

Note: The AENews is accessible from the World Wide Web via http://picol.cahe.wsu.edu
Enter this address carefully, paying close attention to punctuation and spacing (no spaces between parts of the address). Some readers may experience difficulties accessing the site. These are believed to be related to the Internet and to on-line services, not the web site. If you are having a problem accessing the web page, please inform Dr. Catherine Daniels (ph: 509-372-7495, fax: 509-372-7491, E-mail: cdaniels@tricity.wsu.edu)

ISK changing Bravo name

ISK Biosciences has stopped packaging chlorothalonil under the Bravo 720 trade name. The total product inventory of 720 2.5-gallon containers is expected to go to Oregon for early season use on filberts. ISK has requested that the trade name be revised for several Section 24c registrations from Bravo 720 to Bravo Weather Stik. Crops under 24c registrations in Washington include Swiss chard grown for seed (WA950036), non-bearing strawberries (WA880013) and blueberries (WA960013).

WSCPR, WSU pest control tour

The Washington State Commission on Pesticide Registration and Washington State University will jointly host the 1997 Washington Pest Control Tour scheduled for July 22, 23 and 24 in western Washington. The event will be similar to the 1996 tour held in eastern Washington. There will be a different focus for each of the three days. The first day will cover agricultural crops in the Skagit Valley and will include such commodities as vegetable seed, raspberry, strawberry, blueberry, cut flowers, flower bulbs and peas. The second day will cover forestry, Christmas trees and rights-of-way and will take place south of Olympia. The third day will focus on urban pesticide issues such as structural pest control, nursery, landscape and ornamental pest control.

Tour participants will include managers from pesticide manufacturers with responsibility for pesticide registration decisions, state and federal pesticide regulators, and state and federal legislative representatives. Participation in the tour is by invitation only. For more information, contact Alan Schreiber at 509-372-7378.

WSCPR to meet

The Washington State Commission on Pesticide Registration is meeting March 13 in Mt. Vernon, Wash. at the Cottontree Inn (Best Western). The meeting will begin at 10 a.m. The public is invited to attend. The primary agenda item will be review of research proposals. For more information on the meeting, contact Catherine Daniels at 509-372-7492 or by E-mail at cdaniels@beta.tricity.wsu.edu. See page 14 for more information.

EPA proposes FY 1998 budget

The Clinton Administration recently released EPA's proposed budget for the 1998 fiscal year. The proposed budget is $7.6 billion, an increase of $846 million, or 12%, more than EPA's fiscal year 1997 budget. The proposed budget takes into account two major environmental laws passed by Congress last year: the Safe Drinking Waster Act Amendments and the Food Quality Protection Act. To implement both laws, the proposed budget includes $36 million dollars. The proposed budget also includes $35 million to expand right-to-know information programs and $8 million to scientifically assess the risks of pollution to children. The FY 1998 budget request will increase EPA staff by 332 full-time employees to 18,283.

CPB response to Admire

Imidacloprid is used as a soil insecticide under the brand name Admire and as a foliar insecticide under the brand name Provado. In the eastern and mid-western U.S., the insecticide has become the primary means of controlling Colorado potato beetle. In Michigan, for example, more than 80% to 90% of the potato acreage was treated with Admire in 1995 and 1996, respectively. Several other states report similar reliance on the insecticide.

High levels of usage have raised concerns about the likelihood of beetles developing resistance. Several university researchers have been examining Colorado potato beetle populations to determine whether beetle populations are becoming more tolerant of imidacloprid.

Michigan State University researchers Ed Grafius and Beth Bishop collected beetles from fields treated with Admire and reared them in the laboratory for several generations, while the beetles were exposed to imidacloprid. The selected strains were 3.8 to 4.5 times more tolerant of imidacloprid than field-collected populations. Although resistance to insecticides among field populations is commonly 10-fold to 50-fold or greater, this low level of resistance is apparently sufficient to allow survival in the fields under certain conditions. The increase in tolerance to imidacloprid by the selected strains of Colorado potato beetle occurred after 2 years of exposure to the chemical.

From Resistance to Imidacloprid in Colorado Potato Beetles from Michigan, Resistant Pest Management, Winter 1996.

FQPA Update

Because the FQPA requires that all 9,300 existing food use tolerances (registrations) and exemptions (Section 18s) be reassessed by August 3, 2006, with one-third due by August 1999, EPA has its work cut out. To complete the reassessment on time, the agency will have to approve tolerances at the rate of two to three a day, 365 days a year. The Food Safety Advisory Committee established by EPA has determined that organophosphates, carbamates and B2 carcinogens will be assessed first.

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CDC suspects pest spray water
for outbreak of food illness

Source: CDC: Water in Pest Spray Likely Source of Cyclospora in Outbreak, Pesticide & Toxic Chemical News, February 5, 1997.

The Centers for Disease Control recommend that only potable water be used to mix pesticides applied to raspberries, following investigation of a foodborne illness that last summer sickened thousands of people in the U.S. and Canada.

Based on epidemiological investigations and tracebacks, CDC scientists concluded that water mixed with pesticides and applied to Guatemalan raspberries was the most likely source of the illness, caused by the parasite Cyclospora cayetanensis.

Tracebacks by CDC scientists implicated 10 Guatemalan farms as the source of the parasite. Two of these farms obtained water from a river and underground spring. Three of the 10 farms stored water in reservoirs, some of which were open. Although water was filtered, filters were not small enough to remove Cyclospora oocysts, which according to the CDC report, measure 8 to 10 microns in diameter.

CDC scientists suspected water as the carrier for the parasite, because previous investigations of Cyclospora-caused illness have reported water as the transmission vehicle. Although the CDC report concludes that water sprayed on berries is the most likely mode of Cyclospora transmission, it concedes that investigators cannot completely rule out other possible modes of transmission.

Guatemalan raspberry growers export 98% of their crop to the U.S., according to the CDC report. According to the report, these growers apply fungicides, insecticides and growth regulators to raspberries throughout both the growing and harvest seasons.

Growers fight botrytis, or gray mold, with fungicides that include captan , dicloran (DCNA), benomil (Benlate), vinclozolin (Ronilan), iprodione (Rovral), and triadimefon (Bayleton). Most applications occur during the May to June harvest, when extended rainy periods leave raspberries susceptible to fungus infections. Growers apply some fungicides, such as iprodione, the day of picking. They apply others, including triadimefon, one or more days before harvest, in order to ensure sufficiently low residue levels.

Guatemalan raspberry growers apply diazinon as a nematicide and insecticides including malathion, dicofol (Kelthane), carbaryl (Sevin), endosulfan (Phaser), naled (Dibrom), and fenamiphos (Nemacur), between one and 20 days before harvest. Growers apply most growth regulators on young plants before they bear fruit, except for a mixture of nitrogen, phosphorus and potassium, which they spray every 15 days during harvest.

According to the CDC report, Guatemalan raspberry growers generally mix pesticides with water in 50-gallon plastic containers and then use either backpack sprayers or motorized pump machines to apply the mixture onto the soil or directly onto raspberry plants. Sources for the water used to mix pesticides include wells, reservoirs, or, in a few cases, rivers or springs.

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Officially Unofficial

...Alan Schreiber

"Officially Unofficial" is a regular feature that may include information considered inappropriate by some.

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WSU pesticide education

The winter training schedule for Washington State University pesticide education programs is complete. Brochures were mailed October 9, 1996 to individuals with a current pesticide license. Both Pre-license and Recertification courses will be offered this winter. A Spanish recertification class was offered in November. A pre-license aquatic session was offered January 23, 1997. Registration is $40 per day, unless postmarked 14 days prior to the program, in which case it is considered early registration at $30 per day.

In response to comments regarding the Integrated Plant Health Workshop held last season in Puyallup, WSU has scheduled two workshops this year - one in Spokane and one in Puyallup.

More information regarding winter training or registration may be obtained by contacting Cooperative Extension Conferences at 509-335-2830, the WAPP World Wide Web site at http://www.wsu.edu:8080/~ramsay or E-mail: ramsay@wsu.edu.

Recertification Schedule
Each day provides six recertification credits.

Western Washington

Elma Mar. 4, 5
Integrated Plant Health Management Workshop
(registration will be limited to the first 60 people)
Puyallup Feb. 24-27   Spokane Mar. 4-7
Pre-License Schedule
The pre-license program offers no recertification credits. Testing is scheduled for Day 3 in the afternoon.
* Days 1-3 for Private Applicators
* Day 1 for Laws and Safety and Dealer/Managers
* Day 2 for Weed Control
* Day 3 for Insect and Disease Control

Western Washington

Puyallup Mar. 11-13

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Available Reports

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EPA commitments regarding FQPA

The EPA, during Food Safety Advisory Committee meetings to obtain feedback on how best to implement the Food Quality Protection Act, committed to the following actions:

The change in the Section 18 process will likely have the greatest effect during this next growing season. The tolerance setting requirement will severely limit the number of Section 18s that can be granted. Repercussions from this change may already be seen. States are submitting fewer requests to EPA, and EPA is processing fewer. Unfortunately, the slow down in the Section 3 registration process due to the new FQPA requirements only exacerbates this problem. Farmers who thought they would have a new use registered for the season learn that the use has been held up at EPA and are forced to request a Section 18 for the chemical. If a true pest emergency were to arise, it would be very difficult to get a Section 18 granted in time to protect the crop.

Secondly, EPA has outlined an "interim decision logic" plan for making decision on pesticide registration actions until all the FQPA implementation guidelines are finalized. Registration decisions, at least initially, will be conservative and will most likely result in time-limited or conditional registrations. EPA's interim decision logic plan is based on the concept that the total level of acceptable risk for a pesticide is represented by the pesticide's Reference Dose (RfD). This is the level of exposure to a specific pesticide that a person could receive every day during a lifetime without significant risk of a long-term or chronic, non-cancer effect. EPA will compare the RfD to a "risk cup". A full risk cup means that 100% of the RfD has been used. Each registered use on a pesticide label uses a percentage of the risk cup. Minor crops use a disproportionately large percentage of the risk cup, as compared to major crops like corn and wheat. Additionally, EPA will reserve between 5% and 20% of the risk cup for non-dietary exposure. This may result in no new uses being granted for a chemical for which a large percentage of the risk cup has been used, and when the chemical comes up for a review, uses may have to be cut from the label. There is considerable concern that products that have been important pieces of integrated pest management programs could be severely cut or lost all together.

Note: The change in the Section 18 process will likely have the greatest effect during this next growing season. The tolerance setting requirement will severely limit the number of Section 18s that can be granted. Repercussions from this change may already be seen. States are submitting fewer requests to EPA, and EPA is processing fewer.

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FQPA and Apples

...Alan Schreiber

Information used to create this table came from the National Agricultural
Statistics Service --1995. Bearing acres in 1995 for the 9 major states were 345,200. States included were California, Georgia, Michigan, New Jersey, New York, Oregon, Pennsylvania, South Carolina, and Washington.

Agricultural Chemical Brand
Area Applied (1995) Percent Applications (1995) Number Treated acres
Atrazine   1 1.1 3,797
Paraquat Gramoxone 24 1.3 10,770
Simazine Princep 23 1.1 87,336
Azinphos-methyl Guthion 86 3.3 979,678
Carbaryl Sevin 46 1.4 222,309
Chlorpyrifos Lorsban 74 1.8 459,806
Diazinon   7 2.1 50,744
Dicofol Kelthane 2 1.4 9,666
Dimethoate   14 1.3 62,826
Endosulfan Thiodan 16 1.4 77,325
Esfenvalerate Asana 14 1.6 77,325
Fenbutatin-oxide Vendex 3 1.2 12,427
Malathion   10 1.5 51,780
Methidathion Supracide 2 1.1 7,594
Methomyl Lannate 18 2.6 161,554
Methoxychlor   10 1.5 51,780
Methyl parathion   24 2.2 182,266
Oxamyl Vydate 17 1.2 37,282
Oxythioquinox Morestan 2 1.0 6,904
Permethrin Ambush, Pounce 18 2.2 136,699
Phosmet Imidan 67 1.1 840,180
Captan   42 4.5 652,428
Dodine Melprex 8 1.8 49708.8
Maneb   1 2.3 7,939.6
Metalaxyl Ridomil 1 1.1 3,797.2

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FQPA -- the latest

As reported before, EPA has developed and is now implementing an interim strategy for phasing in and applying the requirements of the new FQPA legislation to pending registration and reregistration decisions. During this period, the agency will be establishing new policies as well as revising its current policies. To the greatest extent possible, it will continue to make regulatory decisions.

A. Submissions Now Being Accepted for Priority Review.

1. Section 18 Emergency Exemptions.

The agency's first priority is the review of pending section 18 specific and crisis emergency exemptions and the accompanying determination of whether a tolerance can be established consistent with requirements of the FQPA. A letter sent to the states on October 24, 1996, explains what additional materials and information the agency must consider in order to make a tolerance decision. EPA is currently accepting supplemental information for all pending requests for Section 18 actions and for all new emergency exemption requests.

2. Time-Limited Tolerances and Registrations.

EPA will also give top priority to the review of expiring time-limited tolerances, inert ingredient tolerances or exemption requests, and registrations that have expired or will expire by January 30, 1997. Registrants of these uses have been notified by the agency that they should address the FQPA factors and must have submitted the information by October 1, 1996, and that the additional materials must have been submitted either in the form of a tolerance petition and/or a registration amendment. The agency will continue to accept any supplemental information relative to these actions, but cannot guarantee a decision before the expiration date of existing time-limited tolerances.

3. Reduced Risk Pesticides.

Work will continue on all pending and any new food use registration requests for active ingredients and tolerances that are submitted in conjunction with the agency's Reduced Risk Program. For priority review, these applications must clearly meet the new statutory standard of reasonable certainty of no harm, especially as it relates to special subpopulations, such as children. The agency is currently accepting supplemental information for all pending (food and non-food use) reduced risk applications, and is also accepting new registration applications for reduced risk active ingredients or new food uses of existing pesticides registered under the reduced risk program.

4. Biological Pesticides.

Priority will also be given to the review of biochemical and microbial pesticide active ingredients, tolerances, or exemptions from tolerance. For biopesticides, a complete package is required before a pending review can be completed. The Biopesticides and Pollution Prevention Division will continue to review pending applications and does not intend to reprioritize the in-house applications based on submitted information. The agency is currently accepting information for all pending (food and non-food use) biopesticide applications and is also accepting any new applications for new biopesticide active ingredients for both food and non-food use registrations.

5. Planned Priority System Actions.

Consistent with the priorities identified in items 1-4, the agency is now resuming work on the review of all in-house actions for which a human health risk assessment was completed by August 3, 1996, but further assessment is now required due to the passage of the FQPA. These include actions that were submitted as part of the agency's current planned priority system, which includes new active ingredients, significant new food uses, and inert tolerances or exemption requests.

B. Other Submissions
Now Being Accepted
for Pending Actions

Registrants and applicants may now submit the supplemental information for all other actions that are currently pending within the agency. These types of submissions include, but are not limited to:

1. Pending Applications.

Information may be submitted for registration applications of new chemical or new uses of existing chemical that were submitted to the agency before August 3, 1996. These include any pending food use applications and tolerance petitions, non-food uses with the potential for significant children's exposure, and for chemical pesticide registration actions requiring a human health risk assessment.

2. Reregistration.

Work has resumed on the pesticide chemical cases scheduled for reregistration eligibility decisions in FY 1997. The agency is finalizing its list of chemicals for 1997 REDs and will be notifying affected registrants by letter.

As required by FQPA, EPA will focus its efforts on groups of chemicals, such as the organophosphates, carbamates and B2 carcinogens. In order for EPA to most effectively utilize the information, however, and not be put in a position requiring reliance on broad assumptions and default judgments, registrants are advised to submit the information in a timely fashion.

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How does EPA decide whether
a substance is a carcinogen?

...Allan Felsot

In January, EPA released a revised list of pesticides classified as carcinogens. I counted more than 100 active ingredients. In 1987, there were 53 pesticide carcinogens, according to a National Academy of Science report. The difference seems largely due to increased testing and/or evaluation as part of the reregistration process rather than new compounds registered after 1987. Considering that there are about 300 registered active ingredients for food uses, the current number of classified carcinogens represents about 33% of these pesticides. This is curious, considering that Bruce Ames and Lois Gold's analysis of the Cancer Potency Database, funded by the National Institute of Health at the University of California, Berkeley, shows that about 50% of all synthetic and natural chemicals tested for carcinogenicity are associated with tumors. Does this mean that pesticides are less likely to be carcinogenic on average than all other chemicals? Such a question shows how easy it is to put a positive (or negative) spin on available data. This brings me to the central question of this essay: How does the EPA decide if a chemical is carcinogenic? What spin does EPA place on animal testing data?

The Federal Insecticide, Fungicide, and Rodenticide Act requires testing to determine the carcinogenic potential of pesticides. Actually, the tests determine oncogenic potential, which is the ability to cause benign and/or malignant tumors; a substance causing malignant tumors would be considered carcinogenic. One of the first tests for oncogenic potential is the determination of mutagenic potential, the ability to directly damage or alter DNA. Various types of cellular studies have been developed to determine mutagenicity. EPA views with suspicion any compound testing positive for mutagenicity, because the longstanding but now outdated hypothesis of cancer induction assumes that all carcinogens damaged DNA directly. New research has shown that many nonmutagenic chemicals can cause tumor formation at very high doses but not at low or moderate doses.

EPA's theoretical assumptions about cancer etiology dictate the design of oncogenic potential studies and decisions to classify a compound as carcinogenic. EPA assumes that thresholds for cancer do not exist; a single molecule can eventually lead to tumor production. This rule seems to be a holdover of the idea that carcinogens work by directly mutating DNA, and a single mutation can lead to cancer. Nevertheless, the Food Quality Protection Act speaks of threshold and nonthreshold pesticides to distinguish those that are noncarcinogenic from those classified as carcinogens.

A second EPA assumption is that exposure to the maximum tolerated dose (MTD) over a rat's lifetime is a valid predictor of human risk. Thus, all studies must include the maximum tolerated dose. This dose is determined by feeding a range of doses to test animals for about 90 days (a subchronic test). The maximum tolerated dose is an estimate of the highest dose over a lifetime that will not alter longevity through non-cancer effects. It should cause no more than a 10% weight decrease in treated animals compared to the undosed group. Other benchmarks for the MTD besides no mortality include absence of clinical signs of toxicity and pathologic lesions that would be predicted to shorten an animal's life span.

Usually two to three doses including the MTD are fed to rats during their normal two-year lifespan. Pesticide is mixed with the rats' food, and daily consumption is measured so that doses can be expressed as milligrams pesticide per kilogram body weight per day (mg/kg/day). Researchers dose about 50 animals of each sex and monitor them daily for signs of distress. At the end of the test period, the animals are killed and tissues from multiple organs are examined for a variety of cellular changes in addition to the presence of abnormal growths indicative of tumors. One such chronic feeding study can cost several million dollars.

The EPA reviews studies and classifies compounds as carcinogenic or noncarcinogenic. In addition to animal testing, the EPA may use epidemiological evidence from humans. Epidemiological studies are not conducted on new active ingredients, but older compounds undergoing reregistration may be examined. For example, 2,4-D has received much epidemiological study as well as notoriety. During the mid-1980s, National Cancer Institute epidemiologists claimed that Midwest farmers had a risk of non-Hodgkin's lymphoma that increased in proportion to how long they used the product. A study by Dow Chemical scientists published in Fundamental and Applied Toxicology reviewed 2,4-D epidemiological studies and concluded that a majority of studies supported no association with cancer. I noted that the current carcinogenic pesticide listing excludes 2,4-D.

Once mutagenicity, oncogenicity, and epidemiological studies are completed, the EPA considers the results of the mutagenicity and oncogenicity tests, the types and diversity of tumors, the structural similarity of the pesticide to known carcinogens, and whether positive results have been replicated. A study showing elevated incidence of tumors in dosed animals will weigh heavily in the classification decision, especially if other studies corroborate increased tumor incidence in the same tissue and/or the compound is a mutagen. To characterize carcinogenic hazard to humans, the EPA has adapted a multi-tiered classification scheme developed by the International Agency for Research on Cancer. A substance may be classified within one of six possible groups as human carcinogen (Group A), probable human carcinogen (Groups B1 and B2), possible human carcinogen (Group C), not classifiable (Group D), or noncarcinogenic (Group E). All pesticides EPA considers carcinogenic fall into Groups B2 and C.

The process seems straight forward, but details can be messy. First, consider that, well-trained pathologists must examine thousands of tissue slices, and they may not all agree that a damaged cell has changed to a tumor cell. Manufacturers will argue with the EPA about the interpretation of feeding studies. Second, the criteria that EPA uses to classify compounds into Group B2 and C seem mysterious. B2 represents sufficient evidence of carcinogenicity from animal studies, with inadequate or no epidemiologic data. Group C represents limited evidence of carcinogenicity in the absence of human data. Classification of carcinogenicity seems to depend on evidence ranging from limited to sufficient.

I was curious how EPA judged whether evidence was limited or sufficient. I was particularly interested in how negative data are handled and whether thresholds exist. With readily available data in the book Drinking Water Health Advisory: Pesticides, compiled by the EPA Office of Drinking Water, I used chlorothalonil (Bravo, Daconil) as a test case to see how EPA makes a decision. Chlorothalonil has been classified as a B2 carcinogen. The fungicide is important for many agricultural and non- agricultural uses; its registration could be jeopardized on some crops when its exposure risk is reassessed under the expanded requirements of the FQPA.

The chapter on chlorothalonil lists 13 mutagenicity studies; some were based on cell culture studies, while others involved whole animal feeding studies. Only one test showed evidence of a mutagenic effect. Thus, chlorothalonil is not considered mutagenic.

Fourteen subchronic and chronic feeding studies used various dosing regimens ranging from 0.2 mg/kg/day to 900 mg/kg/day. In 90-day feeding studies, doses did not exceed 3 mg/kg/day; at this dose there were no changes indicative of a tumor. A two-year feeding study with dogs at a dose of 3 mg/kg/day revealed no conclusive compound-related trends. A 12-week feeding study reported by the NCI revealed no effect in mice dosed with 800 mg/kg/day.

Two-year high dose studies gave evidence of tumor formation that EPA evidently weighed very heavily. An NCI study observed kidney tumors at doses of 253 and 506 mg/kg/day. What I find curious is the percentage of animals with tumors. At the high dose, 4 of 49 males and 5 of 50 females had tumors. EPA apparently chose to consider 10% incidence of tumors after feeding rats amounts of chlorothalonil equivalent to nearly a billion times the estimated human exposure (<0.0000001 mg/kg/day, according to the Food and Drug Administration Total Diet Study) representative of sufficient evidence of ability to cause tumors in animals.

Is there corroboration of the NCI rat study? A study in mice at doses of 119, 251, and 517 mg/kg/day showed significant tumor incidence only in males fed 251 mg/kg/day. There was no linear relationship to dose. A different two-year study with rats concluded that dose-dependent increases in kidney tumors occurred at feeding levels greater than 40 mg/kg/day. A study filed in 1989 reported a 13% and 20% increase in tumors in male and female rats fed 175 mg/kg/day for nearly 2.5 years. No tumors formed at doses of 1.5 and 3.3 mg/kg/day.

EPA's classification of chlorothalonil as a B2 carcinogen appears to be based on evidence from the two-year rat and mice feeding studies. It does not seem to matter that the incidence of tumors is incredibly low given the high dose rates. It does not seem to matter that the low doses even in the two-year studies were negative. It does not matter that the 90-day low dose feeding studies showed no toxic or cellular effects at doses of 1.5 mg/kg/day, a dose still a million times greater than the estimated human dietary intake. EPA's decision, however, does demonstrate one final assumption the agency makes about pesticides: negative epidemiologic or animal results cannot prove safety.

B1 & B2 Carcinogens

Group C Carcinogens

Allan Felsot is the environmental toxicologist at the Food and Environmental Quality Laboratory.

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WSCPR considers research proposals

The Washington State Commission on Pesticide Registration will meet March 13 in Mt. Vernon to consider about two dozen research proposals. An overview follows.

1) Support for a processing study for Prowl (pendimethalin) on apples. IR-4 requests $4,000 for the $65,750 study to register the herbicide on apples.

2) The Washington Alfalfa Seed Commission requests $2,500 of a $4,425 study to learn if Savey (hexythiazox) would be an effective miticide in alfalfa seed IPM programs.

3) The Washington Tree Fruit Research Commission requests $7,000 of a $13,100 study to determine whether more selective, less toxic insecticides can be incorporated into stone fruit IPM programs.

4) The Pacific Northwest Canola and Rapeseed Association (PNCRA) requests $4,000 of $8,000 to find ways to control insects that are becoming pests of the newly introduced canola crop.

5) Clover seed growers request $8,000 of a $14,000 project to develop crop protection chemicals for clover seed.

6) The Washington Association of Wine Grape Growers requests $9,000 of a $18,000 project for sucker control and weed management in wine grapes.

7) The Pacific Coast Cranberry Research Foundation (PCCRF) requests $4,983 of a $8,304 project to control weeds in Washington cranberries.

8) The PCCRF requests $5,127 of a $15,535 project to test mating disruption of blackhead fireworm in cranberries.

9) The Mint Industry Research Council requests $10,000 of a $26,700 IR-4 GLP project to register a Goal Herbicide-impregnated fertilizer for mint throughout the U.S.

10) The Washington Red Raspberry Commission requests $8,000 of a $17,000 project to evaulate newer, less toxic insecticides for control of spider mites and root weevils on red raspberry.

11) The Washington Strawberry Commission requests $8,310 of a $14,080 project to evaluate newer insecticides for insect pests of strawberry.

12) Currant growers request $9,160 of a $17,460 project to develop controls for currant borer.

13) The Interstate Professional Applicators and the Washington State Nursery and Landscape Association jointly request $4,250 of a $9,250 project for control of mites on ornamental plants.

14) The Willapa-Grays' Harbor Oyster Growers Association requests $14,000 of a $28,000 project to develop a more environmentally benign method to control burrowing shrimp species in oyster beds.

15) The U.S. Dry Pea and Lentil Council requests $2,000 of a $4,000 project to evaluate new insecticides for control of armyworm, cutworms and aphids.

16) The Northwest Bulb Growers Association requests $11,747 of $19,578 for continuation of a project to develop a control tactic for basal rot on daffodils and blue mold on tulip and iris bulbs.

17) The Puget Sound Seed Growers Association (PSSGA) requests $3,000 of a $6,000 project to evaluate insecticides for control of cabbage seedpod weevil in cabbage and podded Brassica vegetable seed crops.

18) The PSSGA requests $3,000 of a $6,000 project to evaluate pirimicarb for control of aphids on vegetable seeds.

19) The PSSGA requests $2,500 of a $5,000 project to evaulate new insecticides for control of cabbage maggot.

20) The PSSGA requests $2,991 of a $5,982 project to evaluate effects of diquat as a pre-harvest desiccant on vegetable seed quality.

21) The PSSGA requests $1,750 of a $3,500 project to evaulate herbicides for weed control in table beets and Swiss chard grown for seed.

22) The PNCRA requests $2,000 of a $6,200 plant-back study for ethametsulfuron (Mustar) on canola.

Other proposals are expected for apple, barley, pear and potatoes.

For a copy of the WSCPR Progress Report, contact Dr. Catherine Daniels at FEQL, Washington State University -- Tri-Cities, 2710 University Drive, Richland, WA 99352-1671. Phone: 1-509-372-7495. Fax: 1-509-372-7491.

E-mail: <cdaniels@tricity.wsu.edu

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WASS summarizes 1996 Washington crops

Crop Production Summary

Information for these tables came from 1996 Washington Crop and Livestock Summary, February 5, 1997. Washington Agricultural Statistics Service.

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One company's approach
to developing a pesticide

This article is one manufacturer's view of the pesticide development process. I found the perspective to be very educational. (Please do not ask for the name of the company.)
...Alan Schreiber

Pesticide product development may be visualized as a development "funnel". The process begins when scientists synthesize or acquire compounds for initial screening evaluations. Of the thousands of compounds evaluated, only a few show sufficient potential to enter more extensive evaluations. These advance to the discovery stage, where they are evaluated against increasingly stringent performance, registration, and safety criteria. Compounds showing sufficient promise advance to the second, or predevelopment, stage. The objective at this stage is to synthesize, acquire and evaluate enough new compounds to advance two compounds to predevelopment each year. At the end of predevelopment, compounds with sufficiently high potential enter the development stage.

Only 50% of compounds that enter predevelopment are expected to pass stringent safety, manufacturing, and commercial standards of this stage and enter development. Once a compound completes development and is registered, it is ready for commercial launch. A compound requires about eight years from the time it enters the discovery stage until commercial launch. Direct costs will be $30 million, not counting costs associated with failed compounds. Total development costs, including costs associated with discovery research, are $85 million annually. The overall goal of this investment and effort is to launch one new compound each year.

Discovery stage
The discovery stage is globally targeted and managed. This one to two year stage has two objectives. The first is the definition of desirable biological and performance properties in a research mode, primarily laboratory and small-plot global field trials. The second is to gain preliminary information on the compound's safety and commercial potential. Basically, the manufacturer desires enough information on the compound's performance, safety and market potential to justify investing an additional $15 million to $20 million required to take the compound through predevelopment.

Key discovery stage tasks include selection of a compound that demonstrates high potential against one or more key targets in laboratory or greenhouse evaluations. Once a compound is identified, potential use rates, use conditions, and competitive performance are defined. This is done both in laboratory or greenhouse tests and in small-plot global field trials.

While these tests continue, scientists evaluate formulations and manufacturing potential and develop preliminary information on the compound's safety profile and registration potential.

Presuming favorable results, the compound can be protected by patents. Projected sales and profits will warrant additional investment, and senior management will consider the compound for advancement to predevelopment. Advancement to predevelopment represents major organizational commitment.

Predevelopment stage
Predevelopment requires three years. Its one fundamental objective is to take compounds from discovery and complete all work needed to support a decision to commercially develop and launch the compound in the marketplace as a product, or alternatively, to drop it. At the end of predevelopment, there should be no major roadblocks to successful registration and commercialization; the investment required beyond predevelopment is substantial. As a result, the various activities associated with predevelopment are tightly focused on identifying &emdash; and hopefully resolving &emdash; problems that might preclude successful registration and commercialization.

Key tasks associated with this objective include full evaluation of label use rates, use conditions, and competitive performance against key commercial standards. Extensive global field research trials provide this information. Predevelopment is also the stage at which the manufacturer finalizes the formulations it wishes to commercialize and sell; identifies a process route; and, based on the process route, determines sales, manufacturing and supply strategies.

Some of the more critical tasks pursued during predevelopment are in the registration area, because compounds in this stage must prove themselves throughout toxicology, fish, wildlife, and environmental studies required by regulatory authorities around the world. By the end of predevelopment, the experimental phases of all critical studies will have been completed. This in turn will enable a thorough assessment of the compound's safety profile as well as ability to register the compound. These data, combined with validated commercial forecasts, will lead to a comprehensive project assessment and review by senior management.

Development stage
Development requires three years. The basic objective of this stage is to prepare the compound for introduction into key global markets for specific applications. During this stage, outside research organizations and customers help confirm the compound's potential under the widest variety of global environmental, use, and growing conditions. This is the stage during which formulation, packaging and small market development manufacturing facilities are constructed. This is also the stage during which international registration specialists use data collected during discovery and predevelopment to guide the compound through approval for specific applications.

Commercial stage
Once a compound is registered, it moves to full commercial status. Scientists conduct extensive and ongoing training of internal personnel and customers on proper handling and use of the product. Technical staff provides extensive ongoing support of the product in the field, assisting customers with proper label use and investigation of problems. During this stage also, full manufacturing and formulation production begins, and facilities are optimized to market demand and sales schedules.

Ongoing review continues to evaluate and seek new and expanded uses and registrations for the product.

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IR-4 food-use research -- 1997

Information for this article came from the IR-4 Newsletter 27:4

IR-4 program representatives selected for 1997 research essentially all projects that participants at the September 1996 IR-4 Food-Use Workshop rated as top priority. The program complemented these projects with field trials designed to complete the studies within one year of field research.

Participants at the workshop had rated projects as A, B, C, or D. Projects selected as "A" priority were projects that IR-4 would guarantee to research in 1997, while "B" projects would be selected for 1997 research only if funding were available. IR-4 selected 61 "B" projects for 1997 research.

IR-4 field, laboratory, ARS and headquarters coordinators met October 8-10, 1996, in New Brunswick, NJ to schedule the 1997 research program. IR-4 plans to work on 147 projects (studies), of which 10 will be dedicated to reregistration and 10 are planned for efficacy and phytotoxicity purposes. Douglas Rothwell, Minor Use Coordinator for Health Canada, joined the IR-4 coordinators in planning US/Canada joint projects. One study was selected as a joint project for 1997. A total of 514 field trials are currently scheduled for 1997 research in support of the 147 projects.

The number of field trials by region is as follows:

Northeast 69
Northcentral 76
Southern 96
Western 127
Canada 1
Total 514

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Federal Issues


The following tolerances were granted by EPA since the last report (January 1997). These data do not mean that labels have been registered for these uses. These pesticides must not be used until labels are registered with EPA or a state department of agriculture.


A = adjuvant FA = feed additive I = insecticide
D = desiccant FM = fumigant IN = inert
D/H = desiccant, herbicide G = growth regulator N = nematicide
F = fungicide H = herbicide P = pheromone
R=rodenticide V = vertebrate repellent  
Chemical* Petitioner Tolerance
(F) Sodium Bicarbonate
and Potassium Bicarbonate
EPA exempt in or on all raw
agricultural commodities
as a fungicide
(F) Myclobutanil FQPA (a) exempt cucurbit vegetables
(R) Zinc Phosphide FQPA (b) exempt sugarbeets tops &
roots, potatoes

(a) Time limited tolerance expires Nov. 30, 1997
(b) Time limited tolerance expires Oct. 15, 1997

Emergency Exemptions (Section 18)

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Contributors to the Agrichemical and Environmental News:

Alan Schreiber, Allan Felsot, Catherine Daniels, Mark Antone, Eric Bechtel

If you would like to include a piece in a future issue of the Agrichemical and Environmental News, please contact Alan Schreiber. To subscribe to the newsletter, please contact Eric Bechtel.

Contributions, comments and subscription inquiries may be directed to: Dr. Catherine Daniels, Food and Environmental Quality Laboratory, Washington State University, 2710 University Drive, Richland, WA 99352-1671, ph: 509-372-7495, fax: 509-372-7491, E-mail: cdaniels@tricity.wsu.edu

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