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Arsenic (As) is a naturally occurring contaminant found in many ground waters. Arsenic in
water has no color, taste or odor. It must be measured by an arsenic test kit or lab test.
Public water utilities must have their water tested for arsenic. You can obtain the results from
your water utility contained within your consumer confidence report. If you have your own
well, you will need to have the water evaluated. The local health department or the state
environmental health agency can provide a list of test kits or certified labs.
There are two forms of arsenic: pentavalent arsenic (also called As (V), As (+5)) and trivalent
arsenic (also called As (III), As (+3)). In well water, arsenic may be pentavalent, trivalent, or a
combination of both. Although both forms of arsenic are potentially hazardous to your health,
trivalent arsenic is considered more harmful than pentavalent arsenic.
RO systems are very effective at removing pentavalent arsenic. 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) where it does convert trivalent
arsenic to pentavalent arsenic, may not convert all the trivalent arsenic in to pentavalent
arsenic. If you get your water from a public water utility, contact the utility to find out if free
chlorine or combined chlorine is used in the water system.
This Premier reverse osmosis system is designed to remove up to 98% of pentavalent arsenic.
It will not convert trivalent arsenic to pentavalent arsenic. Under laboratory standard testing
conditions, this system reduced 0.30 mg/L (ppm) pentavalent arsenic to under 0.010 mg/L
(ppm) (the USEPA standard for drinking water). Actual performance of the system may vary
depending on specific water quality conditions at the consumer’s installation. In addition to
the independent laboratory standard testing conditions Premier has conducted additional
field testing on our reverse osmosis units to determine trivalent arsenic reduction capabilities.
Based upon Premier field testing, it has been determined that the RO units are capable of
reducing up to 67% of trivalent arsenic from the drinking water.
This reverse osmosis system contains a replaceable component critical to the efficiency of
the system. Replacement of the reverse osmosis component should be with one of identical
specifications, as defined by the manufacturer, to ensure the same efficiency and contaminant
reduction performance. Specific component identification and ordering information can be
found in the maintenance section of this manual, by phone at 1-800-752-5582 or online at
www.premierH2o.com
Arsenic Fact Sheet
