Several government agencies oversee regulations concerning food quality and pesticide residues. Pest management programs must meet a variety of regulatory standards.
Three government regulations in the past two decades have influenced stored product protection in the United States. The Food Quality Protection Act (FQPA) of 1996 called for a review of all pesticides registered by the Environmental Protection Agency (EPA) and mandated that exposure limits and use patterns be revised so that the most vulnerable members of human society, such as children and the elderly, would be protected from exposure. Changes in pesticide labels under FQPA and loss of registrations for certain compounds led to development and consideration of alternative methods of pest control for stored products. One result was the reduction of applied levels of the organophosphorus residual insecticide chlorpyrifos methyl, but several newer pyrethroid and other reduced risk insecticides were registered for grain after that. The grain and feed industries became more interested in integrated pest management, IPM, and these practices were adopted more widely. This has been especially true since grain prices have increased in recent years.
The Clean Air Act, as influenced by the international agreement known as the Montreal Protocol, mandated the phase-out and eventual ban of the fumigant pesticide methyl bromide because of its ability to deplete the protective ozone layer in the upper atmosphere. As a result, much of the recent research and development has dealt with alternatives to methyl bromide for stored product protection. The National Organic Program (NOP) of U.S. Department of Agriculture (USDA) established regulations as to how foods approved as being “organic” should be produced, stored and distributed, with widespread impact on the use of synthetic additives and pesticides. Regulatory constrictions and pesticide registration changes, as with pesticide resistance (see article by Opit and Phillips on page 18), have forced commodity, food and pest control industries to become more focused and sometimes creative to deliver high-quality pest-free products that are competitive in the marketplace.
Pest management programs
Integrated pest management is a decision-making process that utilizes information from monitoring the commodity, sampling pest populations and keeps track of the physical environment to help managers make decisions about executing effective control vs. doing nothing. IPM for stored grain and other stored products involves the general practices of sanitation, proper loading and secure storage, aeration for grain cooling, stock rotation and the use of other effective management and control methods. See sidebar on page 6.
IPM has been widely adopted in production agriculture, including large acreages of field commodities as well as higher value, intensive production of specialty horticultural crops. More attention to post-harvest IPM, particularly in the long-term storage of grains, oilseeds and durable value-added products from these commodities, is needed. New bin construction needs to incorporate aeration for grain cooling and have the potential for gas-tightness to apply fumigation effectively (see below). IPM needs to be part of every company’s sanitation and quality control programs. IPM can be readily incorporated into the standard operating procedures for any grain or feed business.
Fumigant insecticides remain the most effective and popular means of curbing an insect infestation when it is determined that pest numbers have reached an action threshold. Phosphine gas (Fig. 5), generated from aluminum or magnesium phosphide that reacts with atmospheric water vapor, can spread through a grain mass and into grain kernels, killing all eggs, larvae, pupae and adults when used properly.