Expanding water-absorbing beads: a “growing” problem for the ENT surgeon—a scoping review

Background: Superabsorbent polymer (SAP) beads, or water beads, are decorative items often mistaken as toys by children. Their capacity for progressive expansion poses risks when ingested, inhaled, or inserted into the ear or nose. This paper aims to evaluate the growing problem by exploring the breadth of literature to understand the clinical impact and provide clinical practice suggestions.

Methods: A scoping review of Embase, PubMed, Web of Science, and Google to May 2025 identified case reports, series, retrospective reviews, regulatory bulletins, and grey literature describing human exposures.

Results: Seventy-two reports were identified, comprising 50 case reports/series, 14 retrospective reviews, 6 news articles, and 2 regulatory letters, documenting 13,466 exposures. The majority were ingestions (n=13,197; 98%), followed by ear insertions (n=188; 1.4%) and nasal insertions or inhalations (n=81; 0.6%). Most ingestions were managed conservatively, though three deaths and one case of toxic brain encephalopathy were reported. Ear insertions commonly required examination under anaesthesia, with complications including tympanic membrane perforation, ossicular erosion, and one case of profound sensorineural hearing loss (SNHL). Nasal insertions/inhalations almost universally require endoscopic removal under general anaesthesia.

Conclusions: SAP beads are an emerging source of preventable paediatric morbidity. Ingestions can often be managed conservatively, but a 96-hour observation window may be warranted given delayed expansion kinetics. Otologic, nasal, and inhaled cases frequently necessitate early ear, nose and throat (ENT) intervention under anaesthesia. A risk-stratified diagnostic and management algorithm is proposed to guide clinicians.