Alternatives to Formalin
Formalin, a 37% solution of formaldehyde in water, has traditionally been used in the
biological sciences for the fixation and preservation of tissues and whole specimens. It
has fallen out of favor in the past few years because of several undesirable properties: It
is carcinogenic, poisonous, irritating to the skin, eyes & mucous membranes, and at
certain concentrations, flammable. The concentration of formalin vapors that a person
can safely be exposed to over a 40 hour work week is 0.75 parts per million (ppm). This
concentration can easily be exceeded during routine manipulations of open containers of
formalin. Unless absolutely necessary, formalin should no longer be used, and replaced
with one of the materials listed below.
There are two alternatives to formalin currently available:
Carosafe, sold by Carolina Biological Supply Company, http://www.carolina.com
Sold under catalog #85-3341 (4 liter) and #85-3343 (20 liter), this propylene glycol-based
material serves as a safer, far less toxic substitute for preserved specimens.
Formalternate, sold by Flinn Scientific, http://www.flinnsci.com
Also a propylene glycol-based product, this material is sold as a concentrate to be diluted
with water. It is recommended for storage of preserved specimens, but not actual
Effective IMMEDIATELY, the use of formalin should be discontinued unless it is
absolutely required. In such cases, Environmental Health and Safety should be contacted
at (814) 8685-6391 to evaluate potential employee exposure and for recommended
measures to control exposures.