Toward Sustainable Liquid Crystal Displays: A Green Prioritization Framework for Liquid Crystal Monomers Integrating Risk Assessment, Mechanistic Insights, and Regulatory Strategies

Liquid crystal monomers (LCMs), as globally emerging
contaminants,
pose significant challenges to environmental sustainability and green
chemistry principles due to their potential health risks. To support
sustainable chemical management and the design of safer alternatives,
this study established a green chemistry framework for 1,431 LCMs,
enabling the development of a risk-based priority control checklist
that classifies LCMs into high (T1), medium (T2), and low (T3) risks.
Notably, fluorinated LCMs dominated the high-risk category (84.94%
of T1), highlighting them as key targets for substitution. Machine
learning identified hydrophobicity, polarity, and ichthyotoxicity
as key toxicity factors. Experimental validation through zebrafish
RNA sequencing revealed significant disruption of the visual toxicity
pathway, with representative LCMs exposure inducing 30 (T1), 4 (T2),
and 1 (T3) differentially expressed genes. Molecular dynamics simulations
corroborated these findings, demonstrating binding energies to the
Gt enzyme: −147.254 kJ/mol (T1), −82.076 kJ/mol (T2),
and −73.291 kJ/mol (T3). Our verified checklist directly translates
into regulatory strategies guided by the Principles of Green Chemistry:
phase-out mandates for T1 (Prevent Waste), production limits and monitoring
for T2 (Real-time Analysis), and certified safer design for T3 alternatives
(Designing Safer Chemicals). This study provides a principled framework
for the hierarchical control of LCMs, advancing sustainable electronics.