WSU Tree Fruit Research & Extension Center

Postharvest Information Network

Sunday, March 24, 2019

WSU-TFREC/Postharvest Information Network/International Chemical Standards

International Chemical Standards


Infinitesimal residues of agricultural chemicals on fresh fruits and vegetables play a significant role in both domestic and international trade. These residues, even in the absence of information that their presence causes any harm, are often vilified and used as a justifiable reason why treated fruits and vegetables should be avoided, scrubbed with other chemicals, or even excluded from certain countries. At the same time, both national and international medical organizations recognize that diets rich in fruits and vegetables play a major role in improving the health of people, including children, both in the United States and around the world. This recognition comes with the realization that most of these fruits and vegetables produced both in the United States and around the world are treated with crop protection chemicals to maintain product quality.

It is within this dichotomy that the fruit industry of the Pacific Northwest conducts its business of providing fresh fruit to over 50 countries around the world. The Northwest Horticultural Council (NHC), established over 50 years ago, represents this industry on matters relating to both domestic and international pesticide residue standards. The NHC actively seeks to affect policy relating to agricultural chemical residues, serves as a clearinghouse for pesticide residue information on behalf of the industry, and works with regional commodity groups to respond to pesticide residue issues both here and abroad.

Within this framework of activities, today's presentation affords an opportunity to outline some of the key issues we see surrounding pesticide residues.

A Clearinghouse for Chemical Residue Information

The NHC maintains an extensive international database of allowable pesticide maximum residue levels (MRLs) for the majority of chemicals used on apples, pears, and cherries, the most widely exported commodities. We collect this information from a variety of sources in the United States and around the world, but rely most importantly on the U.S. Department of Agriculture (USDA) Foreign Agricultural Service (FAS) staff stationed in many countries around the world. We provide the FAS officials with lists of chemicals most commonly used on fruit grown in our region, they then contact the appropriate officials in their host country and provide us with the most recent information on allowable pesticide MRLs in that country.

The NHC conducts regular updates of this database, but also performs updates as needed based on information we receive from other governmental sources and trade sources. Dr. Wally Ewart of the NHC is a member of the U.S. Delegation to the Codex Commission on Pesticide Residues (CCPR or Codex). The Codex is an international body set up under the United Nation's Food and Agricultural Organization which sets MRL standards for use by member nations, particularly those that do not have the ability to set their own standards. Codex standards can also serve as a default value until a given country conducts its own review and establishes a domestic MRL. It takes about six years to establish a Codex tolerance after an MRL has been established in a member nation. NHC publishes this information on our web site at

Monitoring Changes in Pesticide Residue Policy

While changes in specific MRLs can have a significant effect on trade, the greatest impact often occurs when one of our trading partners moves to create a more restrictive pesticide residue policy. The most recent example of this is the changes instituted almost a year ago in Taiwan that required the establishment of national tolerances for the residues of chemicals used on fruit imported to Taiwan.

While the United States supports the right of each country to establish national standards, establishment must be a clear and open process based on sound scientific principles, so that interested nations can determine how to comply. Based on the concerns of the NHC and other west coast commodity groups, the Unites States government worked with the government of Taiwan to develop a process to establish the necessary MRLs in that country. Based on the original agreement, until July 15, 2000 Taiwan will defer to Codex standards, or if one does not exist, to the MRL standards of its major trading partners. Recently the NHC was informed that Taiwan would defer to Codex standards indefinitely rather than set their own. If a Codex standard does not exist or if the Codex standard is substantially lower than United States standards, registrants must/can submit a data package to establish the necessary tolerance. Once that data package has been submitted, Taiwan will continue to defer to Codex or MRL standards of its trading partners until data review is completed. Despite this agreement, Captan and endosulfan (Thiodan) remain prohibited under Taiwanese regulations. The NHC does not foresee trade disruptions because of this new policy.

Changes in United States Pesticide Laws That Affect International Trade

In the past, the process of registering new pesticides in the United States took substantially longer for certain chemicals than it does now. Usually registrations were obtained in Europe, placed into the Codex registration process, and about the time there was a United States tolerance, there was also a Codex tolerance in place. Now the U.S. Environmental Protection Agency (EPA) has established a fast track for safer and reduced risk pesticides, which means that the United States often has a tolerance for certain chemicals before the rest of the world, without a Codex tolerance as an interim standard. This has been especially true for fungicides, many of which have been registered on tree fruit in recent years. The situation is slowly improving for some of those fungicides but this scenario will repeat itself for many chemicals in the coming years.

Responding to International Pesticide Scares

Attempts by domestic environmental/consumer groups to change pesticide policy by proclaiming treated food was dangerous have not gone unnoticed in the international arena. A recent example is attempts by the Japan Offspring Fund to vilify United States apple exports to that country based on the potential for controversial pesticide residues to exist on the fruit. While these attacks, usually filled with misinformation, are of great concern to the industry of focus, NHC attempts to deflect attention from the specific crop and work with the local USDA FAS officer as the liaison to the local government.

If the imported commodity does not contain volatile residues, it is usually in the best interest of the local government to speak to the safety of imported produce as an indication that they are aware of consumer concerns and are acting responsibly on behalf of consumers by maintaining a safe food supply. A recent example of this occurred in Malaysia where the Malaysian government vigorously defended its imported food safety policy in response to pesticide scare stories similar to that issued by the Japanese environmental groups. In other situations, it may be better not to respond and avoid prolonging the visibility of the issue. These are all judgement calls and must be decided on a case-by-case basis. In any case, the goal of the NHC is to deflect specific attention from our products in those markets.

Managing information relating to international pesticide policy represents a huge portion of NHC's international trade responsibilities and appears to be increasingly important. It is our goal to improve the quality of this information available to growers and shippers to help them avoid potential export problems, while offering expertise and counsel as our industry grapples with unforeseen issues sure to arise around the world.

Mike Willett

Northwest Horticultural Council
6 South 2nd St., Room 903, Yakima, WA 98901

16th Annual Postharvest Conference, Yakima, WA
March 14-15,  2000

Tree Fruit Research & Extension Center, 1100 N Western Ave, Washington State University, Wenatchee WA 98801, 509-663-8181, Contact Us