Glass Fiber Look-A-Like
This is a fragment of a feather barbule. With circular
polarized light the birefringence is easily visible regardless
of the fiber's orientation. Without circular polarized light the analysis would take
longer because the stage would have to be rotated to
observe the birefringence for some of these fibers that may be encountered. Without
polarized light at all the fiber could be mistaken for a
glass fiber.
Transmitted Off Circular Polarized Light Illumination
Definition/Function:
Many different fiber types could be mistaken for glass fiber if the microscope is not
configured for polarized light.
Significance in the Environment:
Bird feather barbule fragments are very common in environmental samples. In indoor
environments they may come from down clothing or furniture,
but they are often from wild birds in the immediate outdoor environment. They may also
be from pet birds in home environments and school
classrooms. Excessive numbers of feather barbules relative to human skin flakes,
clothing fiber, or paper fiber may indicate an exposure problem.
It is often not the feathers that are the health risk but rather bird mites or diseases
that may be associated with the bird exposure.
Characteristic Features:
Associated Particles:
References: