While spaying is traditionally recommended for kitties between 4 and 6 months of age, spaying as young as 8 weeks old is considered safe, according to Cat Channel.
The national drinking water standards state that the maximum residual amount of chlorine is 4 mg/L. Untill recently the USA used chlorine gas extensively for wastewater treatment. Today, the use of chlorine has been forced back.
For practical reasons, the drinking water guideline for benzene is 1 ppb (which is the analytical detection limit) (NHMRC 2004). The remaining chemicals (toluene, ethylbenzene and xylenes) are not recognized as carcinogenic. (IARC 1989) and their drinking water guidelines are much higher (Table 4).