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by stoppingin 1225 days ago
Where did you get that from the article?

From their results section:

> "Interestingly, detergent residue from professional dishwashers demonstrated the remnant of a significant amount of cytotoxic and epithelial barrier–damaging rinse aid remaining on washed and ready-to-use dishware."

2 comments

Yes, the article (and your parent comment) accepts that this is true for professional dishwashers (not household ones):

> A professional dishwasher completes 1 or 2 wash and rinse cycles using 3.5 L of water per cycle. The detergent and rinse aid are automatically dispensed into the water at a concentration of 1.5 to 4 mL/L and 0.1 to 0.5 mL/L, respectively. At these concentrations, the residual dilution factor after rinse ranges from 1:250 to 1:667 for detergents and 1:2,000 to 1:10,000 for rinse aids.

> Household dishwasher detergents in a normal cup and plate washing program typically consume a total of 12 L of water: 4.8 L during the washing cycle, 3.6 L of water for the intermediate rinse cycle, and 3.6 L of water for the final rinse cycle. Between the washing and rinsing cycles, 200 mL of water remains inside the dishwasher. Accordingly, the dilution factor for one 20-g tablet of detergent is 1:80,000 (w/v).

The detergent residue they are talking about there isn't the detergent from washing, it is the rinse aid. Rinse aids are detergents that cut surface tension to let the water bead off faster.

They found nothing wrong with washing with detergent, just using rinse aid to dry in a commercial setting due to the detergent residue the rinse aid could leave.