Environmental monitoring practices relevant to regenerative medicine manufacturing: Insights from a cross-sector survey of regulated facilities in Japan

Introduction Environmental monitoring (EM) is essential for contamination control in regenerative medicine manufacturing, where aseptic handling and operator-dependent processes require adaptable yet robust strategies. Although EM is governed by shared regulatory requirements across manufacturing sectors in Japan, implementation varies considerably depending on product characteristics and manufacturing processes. However, quantitative investigations that position regenerative medicine within the broader landscape of regulated manufacturing sectors remain limited. This study aimed to characterize variation in EM practices across sectors in Japan and identify key factors driving these differences. Methods A cross-sectional questionnaire survey was conducted among EM personnel at regulated pharmaceutical and regenerative medicine manufacturing facilities in Japan. Fifty-five respondents from six sectors completed a 55-item questionnaire. Fifty-four items were numerically encoded and analyzed using PCA, k-means clustering, PERMANOVA, LDA, and one-way ANOVA with effect size estimation (η 2 ). Results EM practices differed significantly across sectors. Major differences included implementation of surface monitoring in Grade B/C-equivalent areas, frequency and approach of media performance testing, and timing of airborne particle monitoring. Regenerative medicine facilities showed a mixed profile, combining frequent media testing with variable monitoring coverage. Clustering further separated groups based on clarity of sampling rationale and microbial identification practices. Conclusion EM practices in regenerative medicine are partially aligned with standardized sterile manufacturing but remain heterogeneous. Identifying high-impact domains provides a basis for improving risk-based EM strategies, documentation, and training in regenerative medicine manufacturing.