by Johnie Crocker
President & CEO, Water Utility Chemicals, Inc.
whether peroxide or another hair bleaching method, or just naturals, are
susceptible to the green monster after a dip in the pool. Most of the time the most severe
cases are peroxide blondes. Natural Blondes can suffer the same dilemma, more especially
if their hair is dry or damaged.
The culprit is not the
chlorine, as Ive seen in many articles. It is dissolved and oxidized metals in the
pool water. The problem can be assisted by extremely high chlorine, greater than 8.0
milligrams per liter (mg/l) or parts per million (ppm). But that is considerably higher
than is recommended for a pool.
The major culprit is of the metals group, copper. Generally the quantity would need to be
greater than 0.5 mg/l. Smaller quantities have created the same phenomenon when compounded
with quantities of iron or manganese that has not totally oxidized. The partially oxidized
iron and manganese will take on the stronger color characteristics of the copper like a
prism does. A prism will reflect the colors around it stronger than the infinite rainbow
it may exhibit in a white room with just the sun shining on it.
I read an article on a web site where someone said the problem was not the algaecide that
the pool owner used. That statement was probably incorrect. The most widely used pool
algaecide due to its effectiveness is a copper product. Used according to the
Manufacturers label, one might add as much as or more than 1.0 mg/l of copper to
their pool. The maintenance dosage is quite often kept at or around 0.5 mg/l. The main
reason that the copper reacts quickly or worse in one pool more than another, in which
both were treated equally, is due to the rest of the chemistry of the pool. With a low pH,
alkalinity, calcium and total dissolved solids, the copper is more apt to stay in solution
and do what it was put in there for, to reduce algae. On the other hand, with a high pH,
and possibly other parameters high, the copper may stay in solution, but it has the
tendency to form a scale or attach to other solids.
Hair, any hair, is susceptible to have metals form a scale on it. The green is just not as
noticeable on other colors like it is on a Blonde. Hair is just a preferred surface, as it
is porous and often the oils in the hair have a high pH, increasing the oxidation process.
Iron and manganese follow suit in this simplified explanation of what is actually called
the "Saturation point" for metals. Iron is normally noticed in pool water, and
is generally treated to be removed, although small quantities might go unnoticed. Pool
owners; on the other hand, do not often test for manganese. Most often it is diagnosed as
just some form of metal. Varied water quality parameters will produce varied saturation
points for these metals whether combined or if just one metal is present.
Pool owners are typically more concerned with algae and are not aware of the rest. Larger
commercial pool owners often create the perfect opportunity inadvertently trying to make
their water less corrosive by adjusting the water parameters to the high end of the
acceptable pool chemistry settings scale. Often they are trying to stop copper corrosion
in their piping system with these adjustments and just happened to use an algaecide with
copper in it. Under these conditions, they should use one of a half a dozen other
algaecides available for pools that are copper free, more especially if their water is
corrosive and they must stop the corrosion as well as the kill the algae. Copper algaecide
should definitely not be used in spas because, one; it produces foam, and two; the warm
water will most definitely cause the copper to oxidize and stain the spa itself, much less
hair and skin.
Removal of excess metals from the pool with a reputable metal chelating agent is
suggested. Most are just called "metal out". They compound the metals to a
particle size large enough that the filter will then remove them. Dont use a
sequestering agent for this purpose, as they just cosmetically cover up the problem and do
not remove it as a general rule. They also are usually a form of phosphate or phosphorus
or have some in it. Phosphates or phosphorus are on the top of food chain for algae and
bacteria. That is why there are phosphorus/phosphate removers for pools.