Walborg Thorsell

Walborg Susanna Thorsell, born 12 February 1919, is a Swedish scientist who performed research mainly on mosquitoes and mosquito repellents.

Education

Thorsell defended her thesis for her doctorial in veterinary medicine at the Swedish Veterinarian Institute in 1967,[1] and is a docent in experimental parasitology.[2]

Research

Anopheles gambiae, malaria mosquito

Thorsell started her studies on mosquitoes while working at the Swedish Defence Research Agency (FOA). At that time claims circulated, from both the United States and the Soviet Union, that the other part was conducting experiments with malaria mosquitos in relations to biological warfare. The Swedish military therefore felt it necessary to develop a mosquito repellant, especially for malaria mosquitoes, to be used by Swedish soldiers. The existing repellants were either not efficient enough or had unwanted side effects, so Thorsell and her group of researchers at FOA began looking for a better agent. The substance diethylamide proved to be an excellent repellant for both malaria mosquitoes and ordinary Swedish forest mosquitoes. But in its unmodified form, it is water soluble and was washed away by the sweat when applied on the soldiers. Thorsells' solution to this was to add the same functional groups as in diethylamide to mandelic acid.[3] This resulted in a mosquito repellant called DEMIDEX, that was manufactured during a number of years.[2][4] DEMIDEX was more efficient than the American DEET, which was and still is the most common active ingredient in insect repellents.

After retiering from FOA, Thorsell has continued her research on mosquito repellants at the zoological institution at Stockholm University. That research resulted in the repellant ingredient IXNIX.[2]

Honours

A family of bacteria, Thorselliaceae, found in vector mosquitoes, mainly with vectors of malaria, has been named after Thorsell. The only genus in the family is the genus Thorsellia of which three species are known so far.[5][6]

Bibliography

A selection.

References

  1. ↑ Thorsell, Walborg (1967). Studies on the effect of hexachlorophene on the cuticle and the intestine from liver flukes, Fasciola hepatics L., incubated in vitro. Acta veterinaria Scandinavica. Supplementum, 0065-1699 ; 20. Copenhagen.
  2. ↑ 2.0 2.1 2.2 "Efter 30 års forskning har Walborg Thorsell fått fram världens bästa insektsmedel" [Thorsell has found the best insect repellant after 30 years of research]. Uppfinnaren (in Swedish) (Halmstad) (6). 2000.
  3. ↑ "Aromatic .alpha.-hydroxyamides with insect repellant properties". www.patents.justia.com. Justia. 19 July 1978. Retrieved 18 February 2015.
  4. ↑ "Information om föremål: Myggbekämpningsmedel" [Information about objects: Insect repellants]. www.tekniskamuseet.se (in Swedish). Swedish National Museum of Science and Technology. Retrieved 22 July 2009.
  5. ↑ Kämpfer, P; Glaeser, SP; Nilsson, LKJ; Eberhard, T; Håkansson, S; Guy, L; Roos, S; Busse, HJ; Terenius, O (2015). "Proposal of Thorsellia kenyensis sp. nov. and Thorsellia kandunguensis sp. nov., isolated from the larvae of Anopheles arabiensis as members of the family Thorselliaceae fam. nov". Int J Syst Evol Microbiol 65 (Pt 2): 444–451. PMID 25385997.
  6. ↑ Kämpfer, P; Lindh, JM; Terenius, O; Haghdoost, S; Falsen, E; Busse, HJ; Faye, I (2006). "Thorsellia anophelis gen. nov., sp. nov., a new member of the Gammaproteobacteria". Int J Syst Evol Microbiol 56 (Pt 2): 335–338.
  7. ↑ Bränd-Persson, Åsa; Thorsell, Walborg (1983). Krigsepidemiologi och hälsovård för totalförsvaret: dokumentation från FOA informationsdag, översiktsdag, Stockholm, 1982-05-05 [Warfare epidemiology and health care within the Swedish total defence : documentation from the FOA conference, Stockholm, 82-05-05]. FOA rapport. C. 5, 0347-7665 ; 54050-H1 (in Swedish). Stockholm: Swedish Defence Research Agency, dept 5. Retrieved 18 February 2015.
  8. ↑ Thorsell, Walborg (1984). Människans fysiska tålighet i brandmiljö: brandgaser och rök [Man's physical tolerance in fires: fumes and smoke]. FOA rapport. C. 5, 0347-7665 ; 54053-H1 (in Swedish). Stockholm: Swedish Defence Research Agency, dept 5. Retrieved 18 February 2015.
  9. ↑ Thorsell, Walborg; Tunón, Håkan (2001). Människan och ohyran: bekämpningsmedel i Sverige förr och nu [Man and Vermin - pesticides in Sweden, past and present]. Studia ethnobiologica, 1403-5359 ; 7 (in Swedish). Uppsala: Centrum för biologisk mångfald. ISBN 91-89232-07-0. Retrieved 18 February 2015.