Performance of fluoride and boron compounds against drywood and subterranean termites and decay and mold fungi

  • S. Nami KartalEmail author
  • Evren Terzi
  • Tsuyoshi Yoshimura
Original Paper


Sodium fluoride (NaF) and disodium octaborate tetrahydrate (DOT) are well-known fungicides for preventing and remediating decay in wood and wood structures, due to their excellent diffusion properties in wood. The efficacy of both compounds against drywood termites is, however, inadequately studied; there is a lack of information on the development of proper protection and control methods against drywood termites using these diffusible chemicals. In this study, the threshold values of fluoride and boron against drywood and subterranean termites and decay and mold fungi were assessed in laboratory conditions. Treated Cryptomeria japonica D. Don (sugi) sapwood specimens with four different concentrations of NaF and DOT applied by either dipping or vacuum processes were subjected to attack by drywood termites, Incisitermes minor (Hagen) for 6 weeks. Treated specimens were also tested against subterranean termites, Coptotermes formosanus Shiraki for 3 weeks. Laboratory decay and mold resistance tests were then performed to determine the efficacy of the compounds against fungal attack. Results showed 80% or greater drywood termite mortality in wood specimens treated with NaF at a retention level of 1.7 kg m−3 or more. In DOT treated groups, higher retention levels (greater than 6.8 kg m−3) were needed to reach up to 80% or more termite mortality. In general, weight losses in NaF-treated specimens were slightly lower than those in DOT-treated ones. Retention levels of around 1.2 kg m−3 for NaF and 1.6 kg m−3 for DOT were high enough to reach the JIS K 1571 threshold requirement of weight loss less than 3% in subterranean termite resistance tests. Slightly higher termite mortality values were seen in the DOT than NaF treatments at respective retention levels. In decay resistance tests, no weight losses were seen at a NaF retention level of 2.3 kg m−3; however, a retention level of nearly 4 kg m−3 for DOT was needed for complete protection against both test fungi. In most cases, lower weight losses were obtained in NaF-treated specimens when compared to DOT. In mold resistance tests, neither NaF nor DOT at even the highest retention level was able to completely inhibit mold growth on the surfaces of treated specimens.


NaF DOT Remedial treatments Termites Fungi 



We gratefully acknowledge the Japan Society for the Promotion of Science (JSPS) for providing the first author a research opportunity at RISH, Kyoto University, Japan under the JSPS Invitational Fellowship.


  1. ASTM D4445-10 (2012) Annual book of American Society for testing materials (ASTM) standards, vol 04.10. West Conshohocken, PennsylvaniaGoogle Scholar
  2. AWPA U1-12 (2012) Use category system: user specification for treated wood. American Wood Protection Association (AWPA) Inc., BirminghamGoogle Scholar
  3. Barnes HM, Amburgey TL, Williams LH, Morrell JJ (1989) Borates as wood preserving compounds: the status of research in the United States. International Research Group on Wood Preservation. Document no. IRG/WP, 3542Google Scholar
  4. BS EN 117 (2005) Wood preservatives‒determination of toxic values against Reticulitermes species (European termites) (Laboratory method). BSI Standards, LondonGoogle Scholar
  5. Clausen CA, Yang VW (2003) Mold inhibition on unseasoned southern pine. International Research Group on Wood Preservation. Document no. IRG/WP, 03–10465Google Scholar
  6. Clausen CA, Yang VW (2005) Azole-based antimycotic agents inhibit mold growth on unseasoned pine. Int Biodeterior Biodegrad 55(2):99–102CrossRefGoogle Scholar
  7. Clausen CA, Yang VW (2007) Protecting wood from mould, decay, and termites with multi-component biocide systems. Int Biodeterior Biodegrad 59(1):20–24CrossRefGoogle Scholar
  8. Drysdale JA (1994) Boron treatments for the preservation of wood: A review of efficacy data for fungi and termites. International Research Group on Wood Preservation. Document no: IRG/WP, 94-30037Google Scholar
  9. Ferster B, Scheffrahn RH, Thomas EM, Scherer PN (2001) Transfer of toxicants from exposed nymphs of the drywood termite Incisitermes snyderi (Isoptera: Kalotermitidae) to unexposed nest-mates. J Econ Ent 94(1):215–222CrossRefGoogle Scholar
  10. Findlay WPK (1953) The toxicity of borax to wood-rotting fungi. Timber Technol Mach Woodwork 61(2168):275–276Google Scholar
  11. Freeman MH, McIntyre CR, Jackson RE (2009) A critical and comprehensive review of boron in wood preservation. Proc Am Wood Protect Assoc (AWPA) 105:279–294Google Scholar
  12. Freitag C, Morrell JJ (2005) Development of threshold values for boron and fluoride in non-soil contact applications. For Prod J 55(4):97–101Google Scholar
  13. Harrow KM (1950) Toxicity of water soluble preservatives to wood destroying fungi. New Zealand J Sci Technol B31(5):14–19Google Scholar
  14. Indrayani Y (2007) The invasive dry-wood termite, Incisitermes minor (Hagen), in Japan: infestation, feeding ecology and control strategies. Departmental Bulletin Paper, Kyoto University Kurenai Research Information Repository—Abstracts for PhD for Graduate School of Agriculture Issue Date: 2007–08, pp 34–35Google Scholar
  15. Indrayani Y, Yoshimura T, Fujii Y, Yanase Y, Okahisa Y, Imamura Y (2004) Survey on the infestation of Incisitermes minor (Hagen) in Kansai and Hokuriku areas. Jpn J Environ Entomol Zool 15:261–268Google Scholar
  16. Indrayani Y, Yoshimura T, Imamura Y (2005) Wood preferences of dry-wood termite Incisitermes minor (Hagen) (Isoptera: Kalotermitidae) to Japanese and U.S. Timbers. In Proceedings of the 6th international wood science symposium, Bali, Indonesia, August 29–31, 2005, p 3Google Scholar
  17. Indrayani Y, Yoshimura T, Yanase Y, Imamura Y (2007) Feeding responses of the western dry-wood termite Incisitermes minor (Hagen) (Isoptera: Kalotermitidae) against ten commercial timbers. J Wood Sci 53(3):239–248CrossRefGoogle Scholar
  18. JIS K 1517 (2010) Test methods for determining the effectiveness of wood preservatives and their performance requirements (in Japanese). Japanese Standard Association, TokyoGoogle Scholar
  19. Kartal SN, Yoshimura T (2016) Borates: a natural way to protect wood against termites. Jan Termit Control Assoc 1(165):7–10Google Scholar
  20. Kartal SN, Shinoda K, Imamura Y (2005) Laboratory evaluation of boron-containing quaternary ammonia compound, didecyl dimethyl ammonium tetrafluoroborate (DBF) for inhibition of mold and stain. Holz Roh Werkst 63(1):73–77CrossRefGoogle Scholar
  21. Klyosov AA (2007) Wood-plastic composites. Wiley, Hoboken, p 698. ISBN 978-0-470-14891-4CrossRefGoogle Scholar
  22. Laks PE, Vehring JK, Verhey SA, Richter DL (2005) Effect of manufacturing variables on mold susceptibility of wood-plastic composites. In Eighth international conference on wood fiber-plastic composites (and Other Natural Fibers). Forest Products Society, Madison, WI, May 23–25Google Scholar
  23. Lebow S, Anthony RW (2012) Guide for use of wood preservatives in historic structures. General Technical Report FPL-GTR-217. Madison, WI: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory, p 59Google Scholar
  24. Lloyd JD, Dickinson DJ, Murphy RJ (1990) The Probable Mechanisms of action of boric acid and borates as wood preservatives. International Research Group on Wood Preservation. Document no. IRG/WP, 1450Google Scholar
  25. Micales-Glaeser JA, Lloyd JD, Woods TL (2004) Efficacy of didecyl dimethyl ammonium chloride (DDAC), disodium octaborate tetrahydrate (DOT), and chlorothalonil (CTL) against common mold fungi. International Research Group on Wood Preservation. Document no. IRG/WP, 04-30338Google Scholar
  26. Muhcu D, Terzi E, Kartal SN, Yoshimura T (2017) Biological performance, water absorption, and swelling of wood treated with nano-particles combined with the application of Paraloid B72®. J For Res 28(2):381–394CrossRefGoogle Scholar
  27. Ohmura W, Momohara I, Makita A (2011) Evaluation of wood preservatives against the drywood termite, Incisitermes minor (Hagen) (II)—Performance of impregnated woods after weathering. 木材保存 (Wood Preservation) 37(6): 273–278. (in Japanese)
  28. Pan C, Wang C (2015) Sodium fluoride for protection of wood against field populations of subterranean termites. J Econ Entomol 108(4):2121–2124CrossRefGoogle Scholar
  29. Pan C, Ruan G, Chen H, Zhang D (2015) Toxicity of sodium fluoride to subterranean termites and leachability as a wood preservative. Eur J Wood Prod 73:97–102CrossRefGoogle Scholar
  30. Schoeman MW, Lloyd JD (1998) International standardization: a hypothetical case study with stand-alone borate wood preservatives. International Research Group on Wood Preservation Document no. IRG/WP 98-20147Google Scholar
  31. Tascioglu C, Umemura K, Kusuma SS, Yoshimura T (2017) Potential utilization of sodium fluoride (NaF) as a biocide in particleboard production. J Wood Sci 63(6):652–657CrossRefGoogle Scholar
  32. Terzi E, Kartal SN, Gerardin P, Ibanez CM, Yoshimura T (2017) Biological performance of particleboard incorporated with boron minerals. J For Res 28(1):195–203CrossRefGoogle Scholar
  33. Williams LH, Amburgey TL (1987) Integrated protection against lyctid beetle infestations. IV. Resistance of boron-treated wood (Virola spp) to insect and fungal attack. For Prod J 37(2):10–17Google Scholar
  34. Yoshimura T (2011) Strategies towards the integrated management of the invasive dry-wood termite, Incisitermes minor. Mokuzai Gakkaishi 57(6):329–339CrossRefGoogle Scholar

Copyright information

© Northeast Forestry University 2019

Authors and Affiliations

  • S. Nami Kartal
    • 1
    Email author
  • Evren Terzi
    • 1
  • Tsuyoshi Yoshimura
    • 2
  1. 1.Faculty of ForestryIstanbul University-CerrahpaşaBahcekoy, IstanbulTurkey
  2. 2.RISHKyoto UniversityUjiJapan

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