Usefulness of donor breast sterilization with slightly acidic electrolyzed water to reduce bacterial count in human...

Human milk banks (HMBs) face challenges in minimizing the disposal of donated human milk (HM). One of the primary reasons for HM disposal in HMBs is samples exceeding the upper limit for the total bacterial count. Pre-expression breast cleaning with tap water is mandated in the guidelines for HMBs as a key hygiene practice for reducing the amount of disposed HM. The primary objective of this study was to investigate the effectiveness of breast cleaning with slightly acidic electrolyzed water (SAEW) for reducing HM contamination at the pre-expression stage.

Twenty-six mothers whose donated HMs did not meet HMB bacterial standards, despite pump changes and intensive hygiene instructions, were included. Over 3 weeks, participants sprayed their breast surfaces with SAEW before expression. Bacterial counts and macronutrients in HM expressed with and without SAEW were compared.

The total bacterial count in HM decreased significantly from 2.9 × 10⁶ colony-forming units (CFU)/mL to 2.3 × 10³ CFU/mL when SAEW was used. The prevalence of mothers whose HM exceeded the bacterial standard decreased from 84.6% to 10% with SAEW use. However, no reduction in spore-forming bacteria, such as Bacillus cereus, was found in this study. In addition, no significant changes in macronutrients or adverse skin reactions were observed.

The use of SAEW for breast cleaning could be an effective and safe hygiene solution for minimizing the need to discard valuable donated HM, especially for donors whose bacterial counts remained high despite hygiene instructions provided by HMB staff.