Development and implementation of a safety evaluation program for chemical fibers

Area of Science:

• Materials Science
• Toxicology
• Textile Engineering

Background:

• Polyester and acrylic fibers are prevalent in consumer products, leading to potential human exposure through skin contact, ingestion (e.g., children's toys), and occupational inhalation.
• Existing occupational exposure limits address polymer manufacturing chemicals, but the safety of finished fibers and finishing agents requires specific evaluation.

Purpose of the Study:

• To assess the toxicological hazards associated with polyester and acrylic fibers during manufacture and consumer use.
• To evaluate the safety of finishing agents and finished fibers through various toxicity tests.
• To determine potential risks from fiber ingestion, skin contact, and inhalation of combustion products.

Main Methods:

• Data appraisal, chemical analyses, and animal testing (bacterial mutation, rat acute oral toxicity, guinea pig skin sensitization).
• Human volunteer trials for skin irritancy and sensitization.
• Acute toxicity testing of finished fibers and migration tests in various solvents (saline, methanol, chloroform).

Main Results:

• No adverse reactions were observed in human or animal testing for finished fibers under normal use conditions.
• Burning acrylic fibers produced more toxic smoke (primarily due to hydrogen cyanide) than burning polyester fibers.
• Migration tests indicated minimal leaching of fiber components (< 3.6 mg/dm2), with leachates containing only polymer and finishing agents.

Conclusions:

• Current and future uses of polyester and acrylic fibers are considered to pose minimal to no toxicological hazard under normal conditions.
• While combustion products present a toxicity risk, normal handling and use are deemed safe.
• Further research may be warranted for specific applications due to the limited biological endpoints addressed.