Release of titanium dioxide from textiles during washing

Area of Science:

• Environmental Science
• Materials Science
• Textile Engineering

Background:

• Titanium dioxide (TiO2) is a widely produced nanomaterial, with pigment-grade TiO2 used on a massive scale.
• Understanding TiO2 release from consumer products is crucial for assessing environmental exposure.
• Functional textiles increasingly incorporate TiO2 for properties like UV absorption and antimicrobial activity.

Purpose of the Study:

• To quantify the release of TiO2 from various functional textiles during washing.
• To analyze the characteristics and size distribution of released TiO2 particles.
• To evaluate the impact of washing on TiO2 content within textiles.

Main Methods:

• Washing six different functional textiles and analyzing released titanium (Ti) content in wastewater.
• Using size fractionation to determine particle size distribution (>0.45 μm vs. <0.45 μm).
• Employing electron microscopy to characterize the morphology and size of released TiO2 particles.

Main Results:

• Most sun-protection textiles released low amounts of Ti (0.01-0.06 wt%) after one wash cycle.
• One antimicrobial textile showed significantly higher Ti release (3.4 wt%) in a single wash.
• Released TiO2 particles were generally roundish, with primary sizes of 60-350 nm, forming small aggregates; most were not in the nanoparticulate range after washing.

Conclusions:

• Functional textiles do release TiO2 particles during washing.
• The majority of textiles studied showed low TiO2 release, with amounts mostly outside the nanoparticulate range.
• Antimicrobial textiles may represent a higher source of TiO2 release into washing effluent.