Arsenic Fact Sheet - Nimbus Water Systems WaterMaker Five WM5-50 Instruction

Arsenic Fact Sheet

Arsenic (AS) is a natually occuring contaminant found in many ground waters. Arsenic in water has no color, taste or odor.
It must be measured by a lab test. Public water uti liti es must have their water tested for arsenic. You can get the results
from your water uti lity. If you have your own well, you can have the water tested. The local health department or the state
environmental health agency can provide a list of certi fi ed labs. The cost is typically $15 to $30. Informati on about arsenic
in water can be found on the Internet at the US Environmental Protecti on Agency website: www.epa.gov/safewater/arse-
nic.html.
There are two forms of arsenic: pentavalent arsenic (also called AS(V), As +5 , and arsenate) and trivalent arsenic (also called
+3
AS(III), As , and arsenite). In well water, arsenic may be pentavalent, trivalent, or a combinati on of both. Special sampling
procedures are needed for a lab to determine what type and how much of each type of arsenic is in the water. Check with
the labs in your area to see if they can provide this type of service.
Reverse osmosis (RO) water treatment systems are very eff ecti ve at removing pentavalent arsenic. RO systems do not
remove trivalent arsenic from water very well. A free chlorine residual will rapidly convert trivalent arsenic to pentavalent
arsenic. Other water treatment chemicals such as ozone and potassium permanganate will also change trivalent arsenic to
pentavalent arsenic. A combined chlorine residual (also called chloramine) may not convert all the trivalent arsenic. If you
get your water from a public water uti lity, contact the uti lity to fi nd out if free chlorine or combined chlorine is used in the
water system.
The WM5-50 system is designed to remove pentavalent arsenic. It will not convert trivalent arsenic to pentavalent arsenic.
The system was tested in a lab. Under those conditi ons, the system reduced 50 ppb pentavalent arsenic to 10 ppb (the
USEPA standard for drinking water) or less. The performance of the system may be diff erent at your installati on. Have the
water tested for arsenic to check if the system is working properly.
The RO component of the WM5-50 system must be replaced yearly to ensure the system will conti nue to remove pentava-
lent arsenic. The component identi fi cati on and locati on where you can purchase the component are listed in the installa-
ti on/operati on manual.
41840-A McAlby Court, Murrieta, CA 92562
6
(800) 451-9343 · www.nimbuswater.com