Ethanedinitrile (EDN syn cyanogen EDN Fumigas) is a relatively new fumigant with the potential to disinfest quarantine pests from radiata pine (Pinus radiata D Don) logs and sawn timber for export This research evaluated the effects of dose (20 g/m3 or 50 g/m3) timber moisture content (green or kiln dried sawn timber) endgrain sealing (sealed or unsealed timber endgrain) and load factor (11 or 44) on sorption of EDN fumigation chambers Chamber loading significantly influenced sorption with higher loading resulting in greater sorption Changes in the dose of EDN did not affect the sorption pattern Increased moisture content and endgrain sealing both reduced sorption but these effects were relatively small and the differences in sorption patterns caused by moisture content or endgrain sealing decreased over time

The surface area of a log is the most important factor influencing MB sorption and desorption rates, with greater surface area resulting in greater (de)sorption rates. Sorption data can now be combined with insect toxicity data to estimate a minimum effective dose of MB for further evaluation, while desorption data can be combined with fumigant plume modelling to assess worker safety. © 2016 Society of Chemical Industry.

High sorption by Pinus radiata (D. Don) logs may limit insecticidal efficacy of a fumigant by rapidly removing it from the treated headspace. The sorption characteristics of a new fumigant, ethanedinitrile (EDN), were quantified for recently harvested pine logs, and the robustness of a proposed EDN sorption model developed for sawn timber was tested. Over a 10-h period, average concentrations were 17.3% � 0.7 of the initial dose for logs with sealed ends and 9.4% � 0.4 for unsealed ends. This is a high rate of sorption compared with other fumigants, such as methyl bromide. A proportional drop in headspace concentration over time was consistent for the two doses (20 and 50 g/m 3 ) evaluated, confirming that EDN sorption is influenced by the dose applied. Bark cover did not significantly influence EDN sorption. A revised sorption model for EDN is proposed here.

Ethanedinitrile (EDN) has been identified as a possible alternative fumigant to methyl bromide (MB) as a phytosanitary treatment for New Zealand export logs A review of MB phytosanitary schedules has indicated that the treatment rates used in New Zealand may be able to be significantly reduced The toxicity of EDN was compared in the laboratory to that of reduced rates of MB using different life stages of the burnt pine longhorn beetle Arhopalus ferus Naked insects were fumigated with MB at 10C and 20C for 4 h or with EDN at the same temperatures for 3 h The mortalities achieved and the CT products calculated indicate that (1) a reduction in MB usage may be possible for the treatment of logs exported from New Zealand and that (2) EDN has potential as a phytosanitary alternative to MB for the treatment of logs

No abstract