Is water stream deflecting in an electric field really based on water's polarity? A common highschool chemistry example for the polarity of water is the experiment where stream of water is deflected under the influence of a charge (electric field).

Now I have come across some condradicting claims, namely this Youtube video from Veritasium (from around 1:50) and more importantly a publication by Ziaei-Moayyed et. al..[1]

These sources suggest that this phenomenon is not based on the polarity of water but charged impurity ions in the water stream. They also claim that the electric field could also only re-orient the molecules, but not deflect them as the electric field also has an opposite effect on the other side of the dipole. This has been bothering me and it is hard to find concluding evidence either way. What are your thoughts?

References:


Ziaei-Moayyed, M.; Goodman, E.; Williams, P. Electrical Deflection of Polar Liquid Streams: A Misunderstood Demonstration. J. Chem. Educ. 2000, 77 (11), 1520. DOI: 10.1021/ed077p1520.
An electrostatic field will attract both conducting and nonconducting materials even though those materials have no initial charge through electrostatic induction. That is why you can pick up lint or aluminum foil with a charged comb or balloon. See this demo with a neutral aluminum can.