Clearing Agents

Clears both Paraffin and Celloidin sections

Rapid acting, recommended for urgent biopsies and routine purposes

Toxic on prolonged exposure

It does not make tissues transparent and it is toxic to the liver (hepatotoxic) after prolonged inhalation

Cheap and does not extract out aniline dyes

Usual clearing time of xylene

Very expensive and it requires 2 changes in clearing solution

Substitute to xylene or benzene

Recommended for clearing embryos, insects and very delicate specimens since it clears 70% alcohol without excessive tissue shrinkage and hardening

Not suitable for routine purposes because it is expensive

Best for nervous tissue, lymph nodes, granulation tissue, and fetal and other delicate, highly cellular specimens, all of which tend to become distorted and to break up on sectioning if cleared in xylene, toluene, or benzene

Causes minimum shrinkage of tissues

Urgent biopsy clearing time of xylene

clearing time of cedarwood oil

Highly flammable

Gives the widest latitude

Properties are very similar to chloroform but it is cheaper

These are slow-acting clearing agents that can be used when double embedding techniques are required.

An excellent and true clearing agent

Its quality is not guaranteed due to its tendency to be adulterated

It is the best of the traditional clearing agents for routine use

Carcinogenic or may damage bone marrow (Aplastic anemia; If antibiotic: Chloramphenicol)

It is slower in action than xylene, but causes less brittleness

It causes considerable hardening and shrinkage of tissues; hence, is not suitable for nervous tissues and lymph nodes.

It acts slower than benzene and is expensive

It becomes milky on prolonged storage

It is miscible with absolute alcohol and paraffin

If tissue or section is incompletely dehydrated, it becomes milky

The most rapid clearing agent

It is not carcinogenic but highly concentrated emit fumes that are toxic upon prolonged exposure

Quality is not always uniform and good and is extremely slow

Clearing time of toluene

Block size for xylene

It is recommended for tough (skin, fibroid and decalcified tissues) and large tissue specimens

Can be used with celloidin sections

It removes aniline dyes and dissolves Celloidin; Tissues become brittle

clearing time of chloroform

Recommended for CNS tissues and cytological studies (esp. Smooth muscles and skin)

Clearing time of benzene

Dehydrates and clears at the same time since it is miscible in both water and paraffin