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The dilutions seem unrealistic, or at least physiologically irrelevant. This is how they get there:

> 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.

So 1:10,000 is a plausible dilution of rinse aid in the rinse water. Unless people are drinking the rinse water (please don't), it's not a dilution that will ever be seen by the body.

Rather, what the body will see is however much residue is left on a mug diluted in whatever the volume of the mug is.

They do sort of address this:

> To study the chemicals in the residue remaining on the surface of dishware after washing, 10 porcelain cups (190 mL size) were subjected to 1 full washing and drying cycle in professional (Winterhalter, GS501, Germany) and household (AEG, GS60AV, Poland) dishwashers and then 1 mL of culture medium was added into them. After shaking and waiting for 5 minutes, the culture medium was collected from the cups, filter-sterilized, and added to the monolayer and differentiated cell cultures directly or in 1:2, 1:5, and 1:10 dilutions.

Except that they wash all the residues off in just 1 ml of medium. They then dilute that 1 ml onto cells:

> The LDH cytotoxicity assay on monolayer Caco-2 cells showed that the toxicity exerted by the dried rinse aid residue on the cups washed in a professional dishwasher still takes place even at a 1:10 dilution (see Fig E9, A). TEER and PF were also measured in differentiated Caco-2 cells, and parallel results were observed when exposed to rinse aid. High concentrations (1:2 and 1:5 dilutions) of the residue severely impaired the epithelial barrier function as measured by the decreased TEER values. In the 1:10 dilution, nearly the same TEER values were observed compared with controls.

So this isn't great, but it also doesn't seem like a big deal. You could rinse a cup in 10 ml of water, gargle with it, and be fine.




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