Diatomaceous Earths – Natural Insecticides
Abstract
The regulatory issues for diatomaceous earth (DE) cover three fields: consumer safety, worker safety, and proof of efficacy against pests. For consumer safety, regulatory issues are similar to those for other additives, and a principal benefit of DEs is their removal by normal processing methods. For worker safety, regulatory issues are similar to those for other dusts, such as lime. The proof of potential insecticide values of DE may be assessed by using the analysis of physical and chemical properties of DE and its effect on grain properties and the proof of efficacy may be regulated by bioassay of standard design. Integrated pest management (IPM), a knowledge-based system, is rapidly providing a framework to reduce dependence on synthetic chemical pesticides. The main principle of post-harvest IPM is to prevent problems rather than to react to them. The specific curative measures using synthetic pesticides should be applied only when infestation occurs. DE and enhanced diatomaceous earth (EDE) formulations hold significant promise to increase the effectiveness and broaden the adoption of IPM strategies, thereby reducing the need for synthetic pesticides. By incorporating DE in an effective IPM program, grain is protected against infestation, loss caused by insects is prevented and grain quality is maintained until the grain is processed. Cases study data on the use of DE for commodity and structural treatment show that DE is already a practical alternative to synthetic pesticides in some applications.
References
Akbar, W., Lord, J.C., Nechols, J.R., & Howard, R.W. (2004). Diatomaceous earth increases the efficacy of Beauveria bassiana against Tribolium castaneum larvae and increases conidia attachment. Journal of Economic Entomology, 97(2), 273-80. pmid:15154445. doi:10.1603/0022-0493-97.2.273
Aldryhim, Y.N. (1990). Efficacy of the amorphous silica dust, Dryacide, against Tribolium confusum Duv. and Sitophilus granarius (L.) (Coleoptera: Tenebrionidae and Curculionidae). Journal of Stored Products Research, 26(4), 207-210. doi:10.1016/0022-474X(90)90023-L
Alexander, P., Kitchener, J.A., & Briscoe, H.V.A. (1944). Inert dust insecticides: Part I. Mechanism of action. Annals of Applied Biology, 31(2), 143-149. doi:10.1111/j.1744-7348.1944.tb06225.x
Alexander, P., Kitchener, J.A., & Briscoe, H.V.A. (1944). Inert dust insecticides: Part II. The nature of effective dusts. Annals of Applied Biology, 31(2), 150-156. doi:10.1111/j.1744-7348.1944.tb06226.x
Alexander, P., Kitchener, J.A., & Briscoe, H.V.A. (1944). Inert dust insecticides: Part III. The effect of dusts on stored products pests other than Calandra granaria. Annals of Applied Biology, 31(2), 156-159. doi:10.1111/j.1744-7348.1944.tb06227.x
Allen, F. (1972). A natural earth that controls insects. Organic Gardening and Farming, 19, 50-56. nov.
Anon, (1981). Federal Register 1981. (pp. 55511-55512). USA.
Anon, (1987). Silica and Some Silicates. In IARC Monograph Series. Lyons: WHO.
Anon, (1991). EPA R.E.D. FACTS: Silicon dioxide and Silica Gel. 21T-1021. 1-4, September.
Arthur, F.H. (2003). Optimization of inert dusts used as grain protectants as residual surface treatments. In: Proceedings 8th International Working Conference of Stored Product Protection, York, U.K.. 629-634.
Arthur, F.H. (2004a). Evaluation of a new insecticide formulation (F2) as a protectant of stored wheat, maize, and rice. Journal of Stored Products Research, 40(3), 317-330. doi:10.1016/S0022-474X(03)00023-7
Arthur, F.H. (2004b). Evaluation of methoprene alone and in combination with diatomaceous earth to control Rhyzopertha dominica (Coleoptera: Bostrichidae) on stored wheat. Journal of Stored Products Research, 40(5), 485-498. doi:10.1016/S0022-474X(03)00060-2
Athanassiou, C.G., Vayias, B.J., Dimizas, C.B., Kavallieratos, N.G., Papagregoriou, A.S., & Buchelos, T.C. (2005). Insecticidal efficacy of diatomaceous earth against Sitophilus oryzae (L.) (Coleoptera: Curculionidae) and Tribolium confusum du Val (Coleoptera: Tenebrionidae) on stored wheat: influence of dose rate, temperature and exposure interval. Journal of Stored Products Research, 41(1), 47-55. doi:10.1016/j.jspr.2003.12.001
Athanassiou, C.G. (2006). Toxicity of beta cyfluthrin applied alone or in combination with diatomaceous earth against adults of Sitophilus oryzae (L.) (Coleoptera: Curculionidae) and Tribolium confusum DuVal (Coleoptera: Tenebrionidae) on stored wheat. Crop Protection, 25(8), 788-794. doi:10.1016/j.cropro.2005.10.015
Athanassiou, C.G., & Korunic, Z. (2007). Evaluation of two new diatomaceous earth formulations, enhanced with abamectin and bitterbarkomycin, against four stored-grain beetle species. Journal of Stored Products Research, 43(4), 468-473. doi:10.1016/j.jspr.2006.12.008
Bartlett, B.R. (1951). The action of certain "inert" dust materials on parasitic Hymenoptera. Journal of Economic Entomology, 44(6), 891-896.
Bertovic, V. (1997). The first experimental application of diatomaceous earth (Protect-It®) in Croatia. In: Proceedings Seminar ZUPP'97, Zagreb, Croatia. 95-99. (in Croatian, summary in English).
Bridgeman, B.W. (1994). Structural treatment with amorphous silica slurry: an integral component of GRAINCO's IPM strategy. In: Proceedings 6th International Conference on Stored-Product Protection, Canberra, Australia. 628-630.
Bridgeman, B.W., & Collins, P.J. (1994). Integrated Pest management in the Grainco, Queensland, Australia, Storage System. In: Proceedings 6th International Conference on Stored-Product Protection, Canberra, Australia. 910-914.
Budavari, S. (1989). The Merck Index. An encyclopedia of chemicals, drugs and biologicals. New Jersey: Merck and Co. Rahway.
Calvert, R. (1930). Diatomaceous Earth. Americal Chemical Society Monograph. Annals Arbor: University Microfilms. Reprint 1976.
Carlson, S.D., & Ball, H.J. (1962). Mode of action and insecticidal value of a diatomaceous earth as a grain protectant. Journal of Economic Entomology, 55(6), 964-970.
Chanbang, Y., Arthur, F.H., Wilde, G.E., & Throne, J.E. (2007). Efficacy of diatomaceous earth and methoprene, alone and in combination, against Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) in rough rice. Journal of Stored Products Research, 43(4), 396-401. doi:10.1016/j.jspr.2006.12.003
Contessi, A., & Mucciolini, G. (1997). Prove comparative insetticida di polveri silicee a base di zeoliti e di farina fossile diatomee. Ravenna, Italy. Report Regione Emilia Romagna, Servizio fitosanitario.
de Crosta, A. (1979). Mother nature's bug killer. Organic Gardening, 26(6), 38-44.
Desmarchelier, J.M., & Dines, J.C. (1987). Dryacide treatment of stored wheat: its efficacy against insects, and after processing. Australian Journal of Experimental Agriculture, 27(2), 309-312. doi:10.1071/EA9870309
Desmarchelier, J.M., Wright, E.J., & Allen, S.E. (1992). Dryacide®: a structural treatment for stored product insects. In: Proceedings 5th Australian Applied Entomological Research Conference. 483-485.
Desmarchelier, K.M., & Allen, S.E. (2000). Diatomaceous earth: health, safety, environment, residues and regulatory issues. In: Proceedings 7th International Working Conference on Stored-product Protection, Beijing, PR China. 309-312.
Dowdy, A.K. (1999). Mortality of red flour beetle, Tribolium castaneum (Coleoptera: Tenebrionidae) exposed to high temperature and diatomaceous earth combinations. Journal of Stored Products Research, 35(2), 175-182. doi:10.1016/S0022-474X(98)00043-5
Ebeling, W. (1971). Sorptive Dusts for Pest Control. Annual Review of Entomology, 16(1), 123-158. doi:10.1146/annurev.en.16.010171.001011
Fields, P.G., & Timlick, B. (1995). Efficacy assessment of Super Insecolo. Report of Agriculture and Agri-Food Canada, Cereal Research Center, Winnipeg, Mb, Canada.
Fields, P.G., & Muir, W.E. (1996). Physical Control. In (. Subramanyam & D.W. Hagstrum (Eds.), Integrated Management of Insect in Stored Products. (pp. 195-221). New York: Marcel-Dekker Inc.
Fields, P.G., White, N., MacKay, A. and Korunic, Z.: Efficacy assessment of Protect-It. Report of Agriculture and Agri-Food Canada, Cereal Research Center, Winnipeg, Mb, Canada, 1996, pages 35.
Fields, P., Dowdy, A., & Marcotte, M. (1997). Structural Pest Control: The use of an enhanced diatomaceous earth product combined with heat treatment for the control of insect pests in food processing facilities. Report prepared for Environment Bureau, Agriculture and Agri-Food Canada and the United States Department of Agriculture.
Fields, P., & Korunic, Z. (2000). The effect of grain moisture content and temperature on the efficacy of diatomaceous earths from different geographical locations against stored-product beetles. Journal of Stored Products Research, 36(1), 1-13. doi:10.1016/S0022-474X(99)00021-1
Fields, P.G. (2003). Laboratory selection for resistance to diatomaceous earth. In: Proceedings 8th International Working Conference of Stored Product Protection, York, U.K.. 776-778.
Fields, P.G., Allen, S., Korunic, Z., Mclaughlin, A., & Staters, T. (2003). Standardized testing for diatomaceous earth. In: Proceedings 8th International Working Conference of Stored Product Protection, York, U.K.. 779-784.
Flanders, S.F. (1941). Dust as an inhibiting factor in the reproduction of insects. Journal of Economic Entomology, 34(3), 470-472.
Golob, P. (1997). Current status and future perspectives for inert dusts for control of stored product insects. Journal of Stored Products Research, 33(1), 69-79. doi:10.1016/S0022-474X(96)00031-8
Hamel, D. (1997). The efficacy of Protect-It (diatomaceous earth) on stored-product pests applying by dusting. In: Proceedings Seminar ZUPP'97, Zagreb, Croatia. 89-94. (in Croatian, summary in English).
Iler, R.K. (1997). Biochemistry of Silicon and Related Problems. New York: Plenum Press.
Iler, R.K. (1979). The Chemistry of Silica. New York: Wiley.
Jackson, K., & Webley, D. (1994). Effects of Dryacide on the physical properties of grains, pulses and oilseeds. In: Proceedings 6th International Conference on Stored-Product Protection, Canberra, Australia. 635-637.
Katz, H. (1991). Dessicants: dry as dust means insects death. Pest Control Technology, 82-84. April.
Kavallieratos, N.G., Athanassiou, C.G., Michalaki, M.P., Batta, Y.A., Rigatos, H.A., Pashalidou, F.G., . . . Vayias, B.J. (2006). Effect of the combined use of Metarhizium anisopliae (Metschinkoff) Sorokin and diatomaceous earth for the control of three stored-product beetle species. Crop Protection, 25(10), 1087-1094. doi:10.1016/j.cropro.2006.02.009
Kavallieratos, N.G., Athanassiou, C.G., Mpassoukou, A.E., Mpakou, F.D., Tomanović, Ž., Manessioti, T.B., & Papadopoulou, S.C. (2012). Bioassays with diatomaceous earth formulations: Effect of species co-occurrence, size of vials and application technique. Crop Protection, 42, 170-179. doi:10.1016/j.cropro.2012.06.016
Kljajić, P., & Perić, I. (2005). Resistance of stored-product insects to insecticides. Pesticidi i fitomedicina, 20, 9-28. (in Serbian with abstract in English).
Korunic, Z. (1994). Dijatomejska zemlja prirodni insekticid (Diatomaceous Earth as Natural Insecticide). In: Proceedings of ZUPP’94, Zagreb, Croatia. 136-148.
Korunic, Z. and Ormesher, P.: Diatomaceous earth - an Alternative to Methyl Bromide. Proceedings Workshop on Alternatives to Methyl Bromide, Environment Canada and Agriculture and Agri-Food Canada, Toronto, Ontario, 1996a, pp. 91-105.
Korunic, Z., Ormesher, P., Fields, P., White, N., & Cuperus, G. (1996a). Diatomaceous Earth an Effective Tool in Integrated Pest Management. In: Proceedings 1996 Annual International Research Conference on Methyl Bromide Alternatives and Emissions Reductions, Environmental Agency and US Department of Agriculture, Orlando, Florida. 81-82.
Korunic, Z., Fields, P.G., Kovacs, M.I.P., Noll, J.S., Lukow, O.M., Demianyk, C.J., & Shibley, K.J. (1996b). The effect of diatomaceous earth on grain quality. Postharvest Biology and Technology, 9(3), 373-387. doi:10.1016/S0925-5214(96)00038-5
Korunić, Z. (1997). Rapid assessment of the insecticidal value of diatomaceous earths without conducting bioassays. Journal of Stored Products Research, 33(3), 219-229. doi:10.1016/S0022-474X(97)00004-0
Korunic, Z., Fields, P.G., Timlick, B., Ormesher, P., & van Natto, C. (1997). The Enhanced Diatomaceous Earth, a Safe, Effective and Long Lasting Grain Protectant. Presented at Food and Agriculture Organization. In: Presented at Food and Agriculture Organization, VIII Round Table on Prevention of Post-Harvest Food Losses, Columbia, Cartagena.
Korunic, Z., & Fields, P.G. (1998). Diatomaceous Earth Insecticidal Composition. U.S.A. Patent 5,773,017.
Korunic, Z. (1998). ReviewDiatomaceous earths, a group of natural insecticides. Journal of Stored Products Research, 34(2-3), 87-97. doi:10.1016/S0022-474X(97)00039-8
Korunic, Z., Cenkowski, S., & Fields, P. (1998). Grain bulk density as affected by diatomaceous earth and application method. Postharvest Biology and Technology, 13(1), 81-89. doi:10.1016/S0925-5214(97)00076-8
Korunić, Z., & Mackay, A. (2000). Grain surface-layer treatment of diatomaceous earth for insect control. Arhiv za higijenu rada i toksikologiju , 51(1), 1-11. pmid:11059067
Korunic, Z. (2001). A new type of grain protectant. In: Proceedings Seminar DDD i ZUPP 2007 – Disinfection, Disinfestation, Deratization and Protection of Stored Agricultural Products, Zagreb, Croatia. 173-208.
Korunic, Z., & Fields, P.G. (2006). Susceptibility of three species of Sitophilus to diatomaceous earth. In: Proceedings 9th Interntional Working Conference Stored-Products Protection, Campinas, Brazil. 681-686.
Korunić, Z. (2007a). The Effect of Different Types of Grain and Wheat Classes on the Effectiveness of Diatomaceous Earth against Grain Insects. In: Proceedings Seminar DDD i ZUPP 2007 – Disinfection, Disinfestation, Deratization and Protection of Stored Agricultural Products, Zagreb, Croatia. 361-373.
Korunic, Z. (2007b). Joint action of ready to use insecticide mixture of plant extract bitterbarkomycin and diatomaceous earth to control stored grain insects. In: Proceedings Seminar DDD i ZUPP 2007 – Disinfection, Disinfestation, Deratization and Protection of Stored Agricultural Products, Zagreb, Croatia. 375-387.
Korunic, Z., & Rozman, V. (2010). A synergistic mixture of diatomaceous earth and deltamethrin to control stored grain insects. In: Proceedings 10th Interantional Working Conference on Stored-Products Protection, Estoril, Portugal. 894-898.
la Hue, D.W. (1978). Insecticidal dusts: grain protectants during high temperature-low humidity storage. Journal of Economic Entomology, 71(2), 230-232.
Lord, J.C. (2001). Desiccant Dusts Synergize the Effect of Beauveria bassiana (Hyphomycetes: Moniliales) on Stored-Grain Beetles. Journal of Economic Entomology, 94(2), 367-372. doi:10.1603/0022-0493-94.2.367
Maceljski, M., & Korunic, Z. (1972). The Effectiveness against Stored-Product Insects of Inert Dusts, Insect Pathogens, Temperature and Humidity. Zagreb, Croatia. Project No. E30-MQ-1. Grant USDA/YU No. FG -YU - 130. Final Report of Institute for Plant Protection.
Mason, L. (1997). Activity of Protect-It in empty granaries against two stored-product pests. Purdue University. Report prepared by Department of Entomology, Food and Pest Management.
Mclaughlin, A. (1994). Laboratory trials on desiccant dust insecticides. In: Proceedings 6th International Conference on Stored-Product Protection, Canberra, Australia. 638-645.
Blacow, N.W., & ed., (1972). Martindale, W.: The extra pharmacopoeia. (pp. 1087-1088). London, UK: Pharmaceutical Press.
Michalaki, M.P., Athanassiou, C.G., Steeberg, N.G., & Buchelos, C. (2007). Effect of Paecilomyces fumosorroseus (Wise) Brown and Smith (Ascohyta: Hypocreales) alone and in combination with diatomaceous earth against Tribolium castaneum Jacquelin duVal (Coleoptera: Tenebrionidae) and Ephestia kuehniella Zeller (Lepidoptera: Pyralidae). Biological Control, 2(40), 280-286.
National Occupational Health and Safety Commission (NOHSC), Australia. (1995). Exposure standards for atmospheric contaminants in the occupational environment: Guidance note on the interpretation of exposure standards for atmospheric contaminants in the occupational environment (NOHSC: 3008): Adopted national exposure standards for atmospheric contaminants in the occupational environment (NOHSC: 1003), 3rd. Canberra, Australia.
Nickson, P.J., Deschmarselier, J.M., & Gibbs, P. (1994). Combination of cooling with a surface application of Dryacide® to control insects. In: Proceedings 6th International Conference on Stored-Product Protection, Canberra, Australia. 646-649.
Nikpay, A. (2006). Diatomaceous earths as alternatives to chemical insecticides in stored grain. Insect Science, 13(6), 421-429. doi:10.1111/j.1744-7917.2006.00111.x
Phillips, T.W., & Bonjour, E.L. (1997). Application of Protect-It to empty grain bins: Insect mortality and deposition rates. Stillwater, USA: Oklahoma State University. Report by Department of Entomology and Plant Pathology.
Rigaux, M., Haubruge, E., & Fields, P.G. (2001). Mechanisms for tolerance to diatomaceous earth between strains of Tribolium castaneum. Entomologia Experimentalis et Applicata, 101(1), 33-39. doi:10.1046/j.1570-7458.2001.00888.x
Rupp, M.M.M., Lazzari, F.A., & Lazzari, S.M.N. (1998). Insect control on stored malting barley with diatomaceous earth in Southern Brazil. In: Proceedings 7th International Working Conference on Stored-product Protection, Beijing, PR China. 77-78.
Quarles, W., & Winn, P. (1996). Diatomaceous Earth and Stored Product Pests. IPM Practitioner, 18(5-6), 1-10.
Rambo, G. (1992). Efficacy of diatomaceous earth from Harper Diatomite Deposit for control of German Cockroaches in living spaces. Appendix A to, M Melosira DE-100 data submitted to US EPA.
Snetsinger, R. (1982). Tests with Dead-End Roach Killer in Rental Apartments. Pennsylvania State University. Report of Department of Entomology.
Snetsinger, R. (1988). Report on Shellshock Insecticide. Pennsylvania State University. Report of Department of Entomology.
Stelle, J.P. (1880). Road dust vs. Cotton-worms. American Entomologist, 3, 251-252.
Stathers, T.E. (2003). Combinations to enhance the efficacy of diatomaceous earths against the larger grain borer, Prostephanus truncatus (Horn). In: Proceedings 8th International Working Conference of Stored Product Protection, York, U.K.. 925-929.
Stathers, T.E., Riwa, W., Mvumi, B.M., Mosha, R., Kitandu, L., Mngara, K., . . . Morris, M. (2008). Do diatomaceous earths have potential as grain protectants for small-holder farmers in sub-Saharan Africa? The case of Tanzania. Crop Protection, 27(1), 44-70. doi:10.1016/j.cropro.2007.04.020
Subramanyam, (. (1993). Chemical Composition of Insecto. St. Paul: M.N: University of Minnesota. Report of Department of Entomology.
Subramanyam, (., Swanson, C.L., Madamanchi, N., & Norwood, S. (1994). Effectiveness Of Insecto®, A New Diatomaceous Earth Formulation, In Suppressing Several Stored-Grain Insect Species. In: Proceedings 6th International Conference on Stored-Product Protection, Canberra, Australia. 650-659.
Subramanyam, (., & Hagstrum, D.W. (1995). Resistance Measurement and Management. In (. Subramanyam & D.W. Hagstrum (Eds.), Integrated Management of Insects in Stored Products. (pp. 231-398). New York, USA: Marcel Dekker Inc.
Subramanyam, (., & Roesli, R. (2000). Inert dusts. In (. Subramanyam & D.W. Hagstrum (Eds.), Alternatives to Pesticides in Stored-Product IPM. (pp. 321-380). Dordreecht: Kluwer Academic Publishers.
USA EPA: Ambient levels and non-cancer health effects of inhaled crystalline and amorphous silica: Health issue assessment. EPA/600/R-95/115, November 1996.
Vassilakos, T.N., Athanassiou, C.G., Kavallieratos, N.G., & Vayias, B.J. (2006). Influence of temperature on the insecticidal effect of Beauveria bassiana in combination with diatomaceous earth against Rhyzopertha dominica and Sitophilus oryzae on stored wheat. Biological Control, 38(2), 270-281. doi:10.1016/j.biocontrol.2006.03.009
Vayias, B.J., Athanassiou, C.G., & Buchelos, C.T. (2008). Evaluation of resistance development by Tribolium confusum Du Val (Coleoptera: Tenebrionidae) to diatomaceous earth under laboratory selection. Journal of Stored Products Research, 44(2), 162-168. doi:10.1016/j.jspr.2007.09.001
Vayias, B.J., & Vassiliki, K.S. (2009). Factors affecting the insecticidal efficacy of an enhanced diatomaceous earth formulation against three stored-product insect species. Journal of Stored Products Research, 45, 226-231.
Villota, R., Hawkes, J.G., & Cochrane, H. (1986). Food applications and the toxicological and nutritional implications of amorphous silicon dioxide. C R C Critical Reviews in Food Science and Nutrition, 23(4), 289-321. doi:10.1080/10408398609527428
Lin, Z.Z.Q., & Korunic, Z. (1998). Field and laboratory experiments with Protect-It, enhanced diatomaceous earth, in P.R. China. In: Proceedings 7th International Working Conference on Stored-product Protection, Beijing, PR China. 745-757.
White, G.D., Berndt, W.L., Schesser, J.H., & Fified, C.C. (1966). Evaluation of inert dusts for the protection of stored wheat in Kansas from insect attack. Agricultural Research Service, United States Department of Agriculture. ARS-51-8.
White, G.D., Berndt, W.L., & Wilson, J.L. (1975). Evaluating diatomaceous earth, silica-aerogel dusts, and malathion to protect stored wheat from insects. USDA/ARS Marketing Research Report.
Wilbur, D.A., Swoyer, G., & Donahy, A. (1971). Effects of standardized diatomaceous earth on certain species on insects. Kansas Agricultural Research Station. Project report No. 5203.
Winks, R.G., Deschmarchelier, J.M., Russell, G.F., Hyne, E., & Allen, S.E. (1994). Phosphine and its application to stored products. Canberra, Australia: SGRL Stored Grain Research Laboratory, CSIRO Division of Entomology. Annual Report.
World Health Organization International Agency for Research on Cancer. (1997). IARC Monographs on evaluation of carcinogenic risks to humans: Silica, some silicates, coal dust and para-aramid fibrils. Lyon, France.
Wright, E.J. (1990). A Trapping Method to Evaluate Efficacy of a Structural Treatment in Empty Silos. In: Proceedings 5th International Working Conference on Stored-Product Protection, Bordeaux, France. 1455-1463.
--
Authors retain copyright of the published papers and grant to the publisher the non-exclusive right to publish the article, to be cited as its original publisher in case of reuse, and to distribute it in all forms and media.
The published articles will be distributed under the Creative Commons Attribution ShareAlike 4.0 International license (CC BY-SA). It is allowed to copy and redistribute the material in any medium or format, and remix, transform, and build upon it for any purpose, even commercially, as long as appropriate credit is given to the original author(s), a link to the license is provided, it is indicated if changes were made and the new work is distributed under the same license as the original.
Users are required to provide full bibliographic description of the original publication (authors, article title, journal title, volume, issue, pages), as well as its DOI code. In electronic publishing, users are also required to link the content with both the original article published in Pesticidi i fitomedicina (Pesticides and Phytomedicine) and the licence used.
Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.