Sulfuryl Fluoride Fumigation as a Quarantine Treatment for the Control of Reticulitermes speratus Kolbe (Blattodea: Rhinotermitidae) in Wood.

Sulfuryl fluoride (SF) was introduced as a fumigant in 1957 and widely used against stored product insects and dry wood termites in wood structures in warm climates. We conducted several experiments on the quarantine treatment of Japanese termites (Reticulitermes speratus) with SF. The efficacy against R. speratus in wood, as well as the wood sorption and penetration capacity, of SF were investigated. The LCt₅₀ and LCt₉₉ values of SF were calculated at two different temperatures and the differences between dry and wet wood at several loading ratios were evaluated as insignificant. Complete pest mortality was proven in scale-up trials with a 90% loading ratio of SF. The fumigant concentration decreased below the threshold limit after 30 min of ventilation. Compared with other alternative methyl bromide fumigants, the main advantages of SF were outlined. SF caused 100% termite mortality with a 90% loading ratio in the scale-up trials (500 L). The present study provides a basis for the use of SF as an alternative to MB for the treatment of termites in wood.

High-risk termites in wood imported to the Republic of Korea are currently treated with methyl bromide (MB), which has ozone-depleting properties and is highly toxic. This study evaluated the effectiveness of sulfuryl fluoride (SF) as a quarantine treatment against Reticulitermes speratus Kolbe (Blattodea: Rhinotermitidae) in wood, along with its wood sorption and penetration capacity. The LCt₅₀ and LCt₉₉ values for SF were 30.87 and 42.53 mg h/L at 23 °C and 151.62 and 401.9 mg h/L at 5 °C, respectively. The SF Ct values did not significantly differ between dry and wet wood at loading ratios of 10%, 30%, and 50% at both 5 °C and 23 °C (p > 0.05). In a closed wooden cube, the LCt₅₀ and LCt₉₉ for SF for R. speratus were 31.59 and 53.34 mg h/L, respectively, indicating an excellent wood penetration ability. SF caused 100% termite mortality with a 90% loading ratio in the scale-up trials (500 L). The SF concentration during ventilation decreased below the threshold limit value (TLV) of 5 ppm within 30 min, confirming that the working conditions were safe. This study provides a basis for the use of SF as an alternative to MB for the treatment of termites in wood.