Report Focuses on Fiber Analysis

A new report made available through the National Criminal Justice Reference Service (the result of an NIJ-funded project) focuses on synthetic fibers that are derived from natural sources, such as viscose rayon, azlon, and polylactic acid (PLA). "With the production of manufactured fibers of natural origin increasing in recent years, these fibers are likely to become more common in regular case work in the forensic science laboratory," wrote the authors. "However, little is known about the changes occurring in their optical and physical properties as an effect of moisture, sunlight exposure, and exposure to various temperatures."



The study examined the effects of environmental degradation on "Manufactured Fibers of Natural Origin" (MFNOs), which are marketed as being biodegradable.

From the study's abstract:

"The study found that except for complete degradation, no significant changes were observed in the optical properties, infrared spectra, solubility, or melting points of any of the fibers in any of the environments for the duration of the experiment.

Morphological changes, however, were observed in two PLA swatches and two viscose swatches exposed to UV light, as well as one azlon fabric submerged in either freshwater or saltwater. All viscose swatches in the composter and water environments eventually deteriorated completely.

These results indicate that forensic fiber comparison can be conducted on such fibers exposed to different environments, while highlighting possible explanations for some observed morphological differences."

You can read the full report here.

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