Homemade disinfectant spray recipes

Clinical Question

Recipes for Homemade Disinfectant Spray

Key Findings

Warning: Bleach is corrosive.[1] Please read/follow manufacturer’s instructions on how to handle bleach products. Do not mix bleach with ammonia-based cleansers or vinegar because it can cause toxic chemical reaction.[1][2][3] Do not leave/use/store bleach within reach of children.[3]

  • Disinfecting solutions can be based on bleach, alcohol, or vinegar.
  • Efficacy of disinfecting solutions depend on base product used, concentration, and contact (dwell) time.
  • All disinfecting solutions should be used in well ventilated areas. Wear gloves when handling mixture, and wash hands after use.[3]
  • Do not mix vinegar with bleach or hydrogen peroxide because it can result in toxic vapors.[4]

Summary of Information

Recipes #1-#3 Dilute Bleach Solution

Ingredients:

  • Bleach
  • Water
  • Spray bottle/funnel

*Each recipe listed below has a different ratio
*Each recipe has been reproduced by vetted sources

Recipe #1: 1:10 ratio (strong - Mark Warner formula) [5]
Combine ~1 ½ cups bleach per gallon of water or ~⅓ cup bleach per quart of water.

Recipe #2: 1:32 ratio (medium - Clorox Formula) [3][5]
Combine ½ cup of bleach per gallon of water or 2 tablespoons of bleach per quart of water.

Recipe #3: 1:48 ratio (dilute - CDC Formula) [2][5]
Combine ⅓ cup of bleach per gallon of water or 4 teaspoons of bleach per quart of water.

Notes about using bleach:

  • Solutions at stronger concentration are more effective at killing pathogens and require less contact time. However, weaker concentrations (1:48, per CDC guidelines) are still effective with adequate contact time, and have lower risks of skin irritation, damage to surfaces, etc.
  • Aim for dwell time (contact time) up to 10 minutes to ensure effective disinfection.[6] Dwell time also depends on different bleach brands. To find out your bleach product’s dwell time, please look to https://www.epa.gov/pesticide-registration/list-n-disinfectants-use-against-sars-cov-2. [5]
  • Bleach solutions degrade rapidly after they are mixed. It is recommended that you make a fresh batch every day. More dilute solutions will degrade faster, so for solutions that need to last longer (up to about a week), mix no more than a 1:4 ratio.[1]
  • Expired bleach may not be as effective. If bleach is expired, add more than the listed amount. [5]

Recipe #4: Alcohol Disinfectant spray (non-vetted source)

Ingredients:

  • 12 ounces alcohol (95%) (preferably ethanol but can use other alcohol)
  • 3 ½ ounces distilled water
  • ½ teaspoon hydrogen peroxide
  • 30-45 drops essential oil as desired (optional. For scent and antiviral and cleaning properties)

Instructions:
Combine water and hydrogen peroxide in a 16-ounce spray bottle. Add in the desired essential oil (can use more than one oil). Add in alcohol. Shake well to combine the mixture.

Notes about using alcohol:

  • Alcohol solutions with at least 70% alcohol are effective against viruses[2]

Recipe #5: Vinegar Disinfectant Spray

Disclaimer: Vinegar solution is not as effective as bleach solution, but can be considered as an option when running out of bleach. Vinegar solution might not be effective for using on surfaces with high risk of contamination. It is recommended to use bleach solution or commercial cleaners.[4]

Ingredients:

  • Vinegar (5%+)
  • Distilled water

Instructions:

  • Combine vinegar with water in a 1:1 ratio.
  • Dwell time for vinegar solution is up to 30 minutes.
  • This vinegar solution can be used on “glass, windows, walls, cupboards, floors, sinks, stovetops and coffee makers”.[4]

Notes about using vinegar:

  • Vinegar is effective at disinfecting some bacteria and viruses, but it is not as effective as bleach and commercial cleaners.6 5% vinegar can eliminate S. choleraesuis and P. aeruginosa (>5.8-6.0 log10 reduction at both exposure times of 30 seconds and 5 minutes) but has low antimicrobial activity against S. aureus and E. coli (< 3 log10 reduction at both exposure times of 30 seconds and 5 minutes).[7]
  • Bleach solution and commercial cleaners has excellent antimicrobial activity (>5.6-8.2 log10 reduction) against all the listed pathogens.[7]
  • Another study found that 10% malt vinegar could inactivate influenza virus.[8]

Author Information

Authors: Thanh Tran, BS, UCSD
Completed on: May 2, 2020
Last revised on: Not yet revised

Reviewed by: Marsha-Gail Davis MD
Reviewed on: May 5, 2020

This summary was written as part of the CoRESPOND Earth 2.0 COVID-19 Rapid Response at UC San Diego. For more information about the project, please visit http://earth2-covid.ucsd.edu

References

  1. Ono M. Everything You Always Wanted to Know About Bleach But Were Afraid to Ask. TSRI - News & Views. https://www.scripps.edu/newsandviews/e_20060213/bleach.html. Published February 13, 2006. Accessed April 29, 2020.
  2. Cleaning And Disinfecting Your Home. Centers for Disease Control and Prevention. https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/disinfectin.... Published April 2, 2020. Accessed April 29, 2020.
  3. How to Make Your Own Disinfecting Solution: Clorox®. Clorox. https://www.clorox.com/resources/coronavirus/how-to-make-your-own-disinfec.... Published April 28, 2020. Accessed April 29, 2020.
  4. Reliable and Scientific Tips for Cleaning With Vinegar -. NSF International. https://www.nsf.org/newsroom/reliable-and-scientific-tips-for-cleaning-wit.... Accessed June 30, 2020.
  5. Best Household Cleaners for the Coronavirus. Wirecutter. https://thewirecutter.com/reviews/best-all-purpose-cleaner/#a-homemade-dis.... Accessed April 29, 2020.
  6. Culver A, Geiger C, Simon D. Safer Projects and Practices for Disinfecting and Sanitizing Surfaces. San Francisco Department of the Environment https://sfenvironment.org/sites/default/files/fliers/files/sfe_th_safer_pr....
  7. Rutala WA, Barbee SL, Aguiar NC, et al. Antimicrobial activity of home disinfectants and natural products against potential human pathogens. Infect Control Hosp Epidemiol. 2000;21(1):33-8.  [PMID:10656352]
  8. Greatorex JS, Page RF, Curran MD, et al. Effectiveness of common household cleaning agents in reducing the viability of human influenza A/H1N1. PLoS One. 2010;5(2):e8987.  [PMID:20126543]
  9. Malik C, Malik C, Maher DA, et al. DIY Disinfectant Spray (Like Lysol Spray WITH VIDEO). 40 Aprons. https://40aprons.com/diy-disinfectant-spray-lysol/. Published April 3, 2020. Accessed April 29, 2020.