Hello.
Thank you for your query at DoctorSpring.com.

I understand your concern but please do not worry.
Tap water is free from contaminants as it undergoes stringent decontamination measures.
Amoebae like Acanthamoeba nad Naegleria can be found commonly in natural water bodies like lakes, ponds etc.
Moreover, infections with these are quite rare.

Practically, there is no risk of amoebic infections from tap water. Even if we say that the water was contaminated, infection is highly unlikely because the risk of infection is approximately 2.6 cases per million exposures. This is around 0.00026 % which is good as nil.
So please be rest assured that you have nothing to worry.

I hope this was helpful.
Feel free to ask queries.

Regards.