Water beads should be kept away from children under 5 years of age, and older children or vulnerable adults should use them under close adult supervision only. Water beads expand and can block the gastrointestinal passage when swallowed, which can cause choking.
Learn more about water beads:
https://www.gov.uk/government/news/opss-issues-safety-alert-to-warn-of-the-risks-of-water-beads
Additional Safety Information
For ages 14+ only.
Do not swallow or ingest. Keep dry and hydrated gel balls away from young children and pets.
Always use suitable eye protection when operating a gel blaster. Never aim at the face or eyes and always follow the safety instructions provided with your gel blaster.