April 01, 1999
by Teresa Acklin
E.P.A. to revise proposed regulations on phosphine, but seeks more data from industry
The U.S. Environmental Protection Agency plans to revise key parts of its proposed regulations on the use of phosphine, a grain fumigant, before several “stakeholders” meetings are held later this year, an E.P.A. spokesman said. However, the agency is seeking more data and alternatives from the grain industry before making its final decision on the proposed risk mitigation measures.
Mark Hartman, chemical review manager for the E.P.A., said that based on written comments received during the 90-day public comment period, some changes would likely be made to three proposals that seem to be of most concern to the grain industry: establishment of a 500-foot buffer zone around structures being fumigated with phosphine, notification of all residents within 750 feet of fumigated structures and lowering the exposure standard to 0.03 ppm from 0.3.
“It's obvious that we need alternatives to those regulations, and there will be some on the table before we go to the stakeholders meetings,” Mr. Hartman told World Grain in late March.
The dates and the format for those meetings are being determined and will be published in the Federal Register some time in May, Mr. Hartman said.
The E.P.A. received more than 500 letters during the public comment period. However, the majority of those were “form” letters, Mr. Hartman said, that dealt only with the impact of the E.P.A.'s proposed regulations on that company's business. He said the E.P.A. had hoped to receive more hard data including monitoring and emissions data from companies that either manufacture or use the chemical as well as suggestions from the industry on how to amend the proposals in order to satisfy everyone involved.
“Most don't offer a great deal of alternatives,” Mr. Hartman said of the written comments the agency had received.
Tom O'Connor, director of technical services for the National Grain and Feed Association, Washington, D.C., said that while the industry supports the safe use of fumigants to prevent exposure of workers and others to any harmful effects of phosphine, most people in the industry believe the current requirements are adequate.
“We believe that the safety record of phosphine has been excellent,” Mr. O'Connor said at the annual conference of the Grain Elevator and Processing Society, held in March in Tampa, Florida, U.S. Both Mr. O'Connor and Mr. Hartman participated in an environmental operations issue forum at the GEAPS conference.
“As we analyze the E.P.A.'s proposed risk mitigation measures, our overall analysis is that most of them are either unworkable or unnecessary or both,” Mr. O'Connor said. “We believe that if they were to be implemented, it would severely restrict the use of phosphine and have a major operational and economic impact on our industry.”
Grain quality would be significantly and negatively impacted by the E.P.A.'s proposed regulations, he said. “Not only would (the regulations) impact grain quality, but they would also impact the value of our grain and grain products both in storage and in transit,” he said.
The restrictions also would have a negative impact on the United States' international competitiveness on grain exports, Mr. O'Connor said.
Chuck Estes, general manager of Midland Fumigant, Inc., Leavenworth, Kansas, said no one in the industry is opposed to better education about phosphine usage. “Safety is number one on everybody's agenda,” he said.
But instead of imposing more stringent requirements on those who are using phosphine legally and safely, the E.P.A. should address misuse through education and enforcement of current label requirements, he said. “At this point, I think we've done everything the E.P.A. has asked us to do,” Mr. Estes said.
Kansas researcher responds.
The E.P.A. has received phosphine monitoring and emissions data from registrants (chemical manufacturers) and from a research group in Australia. But a grain scientist at Kansas State University, Manhattan, said it would take a concerted effort from U.S. country grain elevators to convince the E.P.A. that current safety regulations for phosphine are adequate.
Carl Reed, a grain storage specialist in K-State's Department of Grain Science and Industry, has submitted research from a project funded by a grant from the Kansas Department of Agriculture's pesticide section aimed at characterizing how phosphine behaves during a routine fumigation in a typical upright concrete Kansas grain elevator.
The research project, which began in August 1998 and will continue through the end of this year, was funded in response to a state compliance issue and was unrelated to the E.P.A.'s re-registration process of phosphide, Dr. Reed said.
Using some of the most advanced technology in sensor instrumentation, Dr. Reed has so far documented more than 16,000 phosphine readings in worker areas during grain fumigations.
The sensors each about the size of a hand-held calculator were placed where workers would be found in the grain elevator: over the top of the bin, at the fumigation applicator and in tunnels. Monitors also were place in the bin itself between the surface of the grain and the bin roof. Every 15 minutes the sensors took a reading and logged that information into an internal computer.
“The data suggest that elevator workers have routinely been exposed to phosphine levels well above the current exposure limit,” Dr. Reed said, adding that there was no evidence that these higher levels of exposure have had a negative effect.
He said the data suggest that the E.P.A.'s proposal to lower exposure levels to 0.03 ppm is neither necessary nor feasible. “There is reason to believe that the atmosphere in working areas that these data have documented is, and for decades has been, routine and common, and that gas masks are seldom, if ever, worn during the performance of routine tasks in this atmosphere,”
Dr. Reed wrote to the E.P.A. ‘The lack of an abnormal illness level in elevator workers exposed to phosphine levels above 0.3 ppm appears to indicate that the current standard contains an adequately large safety factor.” Dr. Reed said that in his experience, the proposed 0.03 ppm exposure level could not consistently be measured accurately with the type of equipment that elevator workers must use in the field. “We can measure it in the lab, but not in the field,” he said.
His research also suggests that the proposed 500-foot buffer zone and restricted area around all fumigated structures is not necessary. In direct response to the E.P.A.'s concern with phosphine exposure to residential bystanders, Dr. Reed set up his sensors outside the fumigated structure. “What we found was just what the professional applicators have been saying all along as soon as the phosphine is released from a confined space, it dissipates so rapidly that concentrations a few feet away can't be measured,” he said.
Proof in numbers.
Dr. Reed said it may fall to the grain handling industry to prove that the E.P.A.'s concerns are unfounded or demonstrate that its concerns about phosphine can be addressed in more effective ways. “That proof must come not in the form of opinions no matter how well informed but rather in the form of numbers from real-life situations,” he wrote in a letter to the Kansas Grain and Feed Association.
He urged the association and its members to present “piles of data” from phosphine fumigations at Kansas elevators to the E.P.A. at the stakeholders meetings, and even outlined what kind of data the elevators should collect (see box on Page 45). “I believe that a big pile of data would have more influence on the E.P.A.'s actions than anything else that could be done,” Dr. Reed said.
The E.P.A. has planned stakeholders meetings in Kansas City, Sacramento and Atlanta. (The dates will be announced in May.) The format of the stakeholders meetings will likely be part public discussion and smaller, more in-depth group discussions, said Mr. Hartman of the E.P.A.
“We want these to be workshops as much as public meetings,” he said.
Even though the 90-day public comment period ended March 23, Mr. Hartman said the agency would continue to accept comments and data throughout the entire re-registration process.
“The 90-day comment period was intended to get as much information to the agency as possible, so we can revise our proposal prior to the meetings,” Mr. Hartman said. “That does not mean that this is the only opportunity for people to have input or that we have closed the doors to any source sent to the agency. That window of opportunity will continue to be open throughout this entire process.
“It is important, however, to try and get as much information as we can in terms of alternatives and impact early on in the process, so we can reflect on those when we go into the stakeholders meetings. We don't want to waste a lot of time at those meetings going over old ground.”