There are many mounting mediums which do not need any hydrocarbon solvents and are safe and are cheap. These include Fructogiycerol and modified Brun's medium; PVA- lactic acid and PVA - glycerrol mountants; the gum arabic mediums and the glycerin jellies.
No-one has to use phenol in a slide preparation process these days, if you chose an appropriate mounting medium. Besides the health issues, there is a risk that traces of phenol can cause blackening of slide mounts. Personally I mount thrips in Canada balsam, which is OK provided you have a phase contrast microscope to study them with. Relevant methodology is discussed in:
U.G.A.I. Sirisena, G.W. Watson, K.S. Hemachandra & H.N.P. Wijayagunasekara (2013) A modified Technique for the preparation of specimens of Sternorryncha for taxonomic studies. Tropical Agricultural Research, 24 (2): 139 - 149 (attached).
Thank you for answering my questions. However I would like to add that i'm looking for an alternative to phenol that also works for quick slide preparation. It's a method that should take around 10 minutes. I have many specimens to identify, so i need to follow a quicker method which requires the use of phenol.
I agree with Gillian, Hoyer’s mounting media is excellent for mounting thrips slides for rapid identification. It is cheap, safe and eaay to use. Some disadvantages are the long period needed to dry out and that they are semipermanent.
You can check our website to prepare Hoyer’s mounting media: