by Tom Mueller and James Feston Insects Limited
As the potential for boundary line and buffer zone restrictions continues to be suggested by the EPA and USDA, there is a need to reduce human exposure from fumigants. After six years of commercial use, new research has uncovered how to reduce fumigant emissions even more.
Because of this potential for boundary line restrictions, we have seen an increased demand for a liquid based solution scrubber. The Fumigant Scrubber is a mechanical unit with the ability to alter the chemistry of a toxic fumigant (methyl bromide and sulfuryl fluoride) which can be released into the atmosphere without danger to living creatures or the environment.
In previous newsletter articles, we published data reflecting the efficacy of the Fumigant Scrubber. As we continue to encounter situations which require a 0 parts per million (ppm) release of fumigant into the atmosphere or populated area, we are forced to test new and effective methods for use of the system. For many years, fumigators have been recirculating the atmosphere of a grain bin for even distribution during fumigations. We have recently taken a page out of the grain bin fumigation book, and we are now testing a recirculation method. By recirculating the scrubber output, we can pull the exhaust through the scrubber multiple times. This allows the fumigant to be passed through the scrubber as many times as necessary for a 0 ppm reading. The new methyl bromide label requires that certain buffer zones be calculated and a safe distance enforced by the fumigator. We believe all fumigants will have a similar label requirement in the future.
This graph reflects the amount of time (in minutes) it takes to scrub 80 oz. of methyl bromide (Q-Gas for quarantine purposes) in a 250 gallon (950 liter) tank at 67°F (19.5°C).
Insects Limited and Fumigation Service & Supply are currently working on a phosphine scrubber that will help reduce boundary line and buffer zone emissions of the popular phosphine fumigant. More on this Fumigant Scrubber will be presented at the 12th Fumigants & Pheromone Conference in Adelaide, South Australia, in March.