Is It Safe to Wash Fruit & Vegetables With Soap?

Is it safe to wash fruit & vegetables with soap?

Check out this answer from Consensus:

The research indicates that washing fruits with food-grade soap can significantly reduce contamination levels, making it a safe and effective method. However, the use of regular dish soap for washing vegetables does not show the same level of effectiveness and may not be advisable due to potential health risks from soap residues. It is recommended to use food-grade soap for washing fruits and to rely on thorough rinsing with water for vegetables to ensure safety.

The safety and effectiveness of washing fruits and vegetables with soap have been topics of interest, especially in the context of reducing contamination from heavy metals and microbes. This article explores the findings from recent research to determine whether using soap is a safe and effective method for cleaning produce.

Heavy Metal and Microbial Contamination

Fruits and vegetables, particularly those grown near roadsides, are susceptible to contamination by heavy metals such as lead (Pb), cadmium (Cd), and arsenic (As), as well as harmful microbes like Escherichia coli and Salmonella typhi1. These contaminants pose significant health risks, making it crucial to adopt effective washing methods.

Effectiveness of Washing with Soap

Study 1: Roadside Fresh Fruits

A study investigated the impact of washing treatments on the contamination levels of roadside fruits. The research employed a randomized block design and used both running water and food-grade soap for washing. The results indicated that washing with food-grade soap significantly reduced the levels of heavy metals and microbial contaminants. Specifically, the levels of Pb and Cd were reduced to 0.000 mg/kg, As to 0.041 mg/kg, E. coli to 0 kol/g, and Salmonella typhi to 0 kol/25g1. This suggests that using food-grade soap can be highly effective in decontaminating fruits.

Study 2: Vegetables in Ilam City

Another study focused on the parasitic and microbial contamination of vegetables in Ilam city and evaluated the effectiveness of different washing procedures. The study involved washing vegetables with water and dish soap. The findings revealed that 40.6% of the samples had parasitic contamination after washing with pure water, and 43% after washing with dish soap. Additionally, 70.9% of the samples had parasitic and bacterial contamination in both wastewaters. The study concluded that there was no significant difference between washing with water and washing with dish soap in reducing microbial contamination2. This indicates that dish soap may not be effective in eliminating microbial contaminants from vegetables.

Safety Concerns

While food-grade soap has shown effectiveness in reducing heavy metal and microbial contamination in fruits, the use of regular dish soap for washing vegetables did not demonstrate significant benefits. Moreover, there are concerns about the potential ingestion of soap residues, which could pose health risks. Therefore, it is essential to use only food-grade soap specifically designed for washing produce.

Is it safe to wash fruit & vegetables with soap?

Donald Schaffner has answered Unlikely

An expert from Rutgers University in Microbiology, Food Safety

There’s a bunch of people out there recommending you wash your fresh produce with soap. This is not a good idea. Soap is known to cause vomiting and or diarrhea. It’s for washing hands not for use on food. Evidence:

Here is the MSDS (Material Safety Data Sheet) for Dawn Dish Soap) saying Ingestion: May result in nausea, vomiting, and/or diarrhea.

Here is one for hand soap saying Ingestion: May cause mild gastrointestinal irritation with nausea, vomiting, diarrhea and abdominal pain.

Here is a letter to the editor from Pediatrics (1972) entitled Detergent Toxicity. Finally, there is this article.

Stay home if you can, wash your *hands* and use hand sanitizer, and take care of those who need it most. Also don’t wash your produce in soap.

Is it safe to wash fruit & vegetables with soap?

Jason Bolton has answered Unlikely

An expert from University of Maine in Food Safety

I fully agree with Dr. Schaffner and the links he provided. Soap and water should only be used on food contact surfaces such as cutting board, countertops and utensils. As most produce is porous, the soapy water may enter the food.

Is it safe to wash fruit & vegetables with soap?

Francisco Diez-Gonzalez has answered Likely

An expert from University of Georgia in Food Safety

I just want to clarify that by soap, I am not talking about detergent. I mean hand soap. Yes, it is safe as long as the soap is rinsed thoroughly, but I would not advise it as a better method than just plain water, since I do not have data to support whether it can be thoroughly rinsed off.

Is it safe to wash fruit & vegetables with soap?

Robson Machado has answered Unlikely

An expert from University of Maine Cooperative Extension in Food Safety, Microbiology

I agree with Dr. Schaffner and Dr. Bolton. In any recommendation for the use of soap or another detergent, there is always a rinse step. That step is there exactly because we do not want to ingest soap. Soap also works best on non-porous surfaces, which is not the case in fruits and vegetables. 

Is it safe to wash fruit & vegetables with soap?

Nigel Cook has answered Unlikely

An expert from Jorvik Food and Environmental Virology in Virology

This is not recommended at all. Soap ingredients may cause adverse health effects if ingested. Washing fruit and vegetable surfaces thoroughly in clean water should reduce any potential microbial contamination. Thirty seconds in running water is effective at reducing virus contamination of fruit and vegetables https://www.sciencedirect.com/science/article/abs/pii/S0168160508002365.