A pack of bacteriostatic water is five materials: a glass vial, a rubber stopper, an aluminum crimp seal, a plastic flip-off cap and a paperboard carton. Only some of them belong in ordinary recycling, and the laboratory’s own waste rules always come first. This guide covers what the components are and where each typically goes.
The components
| Component | Material | Typical route |
|---|---|---|
| Vial | Type I borosilicate glass (some products use Type II soda-lime glass or plastic) | Laboratory glass waste. Borosilicate has a different melting point from container glass and contaminates municipal glass recycling, so most curbside programs refuse it. |
| Stopper | Bromobutyl or chlorobutyl rubber | General laboratory waste; not recyclable. |
| Crimp seal | Aluminum | Recyclable as scrap metal where the laboratory collects it separately; small pieces are often rejected by mixed recycling sorters. |
| Flip-off cap | Polypropylene (resin code 5) | Recyclable where PP is accepted, though small items may fall through sorting equipment. |
| Carton and insert | Paperboard | Ordinary paper recycling once any labels required for records have been retained. |
Empty vials and residual liquid
Residual bacteriostatic water is a dilute aqueous solution of benzyl alcohol. Many laboratories are permitted to dispose of small residual volumes to drain with plenty of water, but the laboratory’s chemical hygiene plan and local wastewater rules decide that, not the supplier. Vials that were used to prepare solutions of other materials follow the disposal route for those materials, not the route for the water. See disposing of expired or opened vials.
A practical separation routine
- Keep a small container for aluminum crimps and one for polypropylene caps at the bench where vials are opened. The flip-off cap comes off at first opening and the crimp is removed with a decapper at disposal, so both are easy to capture.
- Keep the carton until the last vial in it has been discarded: it carries the lot number and expiration date that link the vials to the certificate of analysis, and the reagent log should reference it before it goes to recycling. See lot numbers and traceability.
- Do not deface the printed vial label before the vial is discarded; if a vial is retained as a sample, its label is the only traceability it has.
Reducing packaging in the first place
Because the vial is the largest fixed cost per unit of packaging, matching vial size to usage reduces waste more than anything done at the disposal end: a laboratory that uses 5 mL at a time produces far less glass per litre from 10 mL vials than from 3 mL vials, and far less wasted liquid than from 30 mL vials it cannot finish in 28 days. See how to estimate monthly usage and pack sizes explained.
Related
Vials: glass vs. plastic, stoppers, crimp seals and flip-off caps · SOP template
All BAC Water Supply products are supplied for laboratory research use only and are not for human or veterinary use.