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To better appreciate the power of using a vitamin as the de-chlorination agent in the Vitashower, the hazards in our water supplies must be better understood. These dangers are real and should not be overlooked or accepted by the general public. Chlorine is universally used to chemically disinfect public water systems because of its toxic effect on harmful germs, bacteria and disease-causing organisms. The water we use from city water systems has been treated by chemicals such as chlorine and chloramines. By definition, "chlorine is a nonmetallic element occurring naturally as a poisonous, greenish-yellow gas with an irritating, pungent odor." As defined above, chlorine is a toxic gas. With greater exposure to toxic chlorine contained in water supplies, the potential health dangers we face become more real. During the bathing process, the chlorine evaporates out of the water and is inhaled. This toxic gas can also spread through the house and be inhaled by others. Some reports claim that as much chlorine enters the body by inhaling steamy chlorinated shower vapors or through the open pores of the skin as that which enters the body by drinking chlorinated water during the entire day. This increased exposure to the adverse effects of chlorine by household residents can be from 6 to 100 times more than medically recommended. Chlorine also attacks the skin and skin oils, creating a dermal drying effect. Shower water can also cause or worsen skin irritations and rashes as well as drying the skin. Showering and bathing in chlorinated water will also result in the breakage of hair shafts. Because chlorine is absorbed into the body through the skin, additional physical problems can ensue. Chlorinated water can also irritate eyes, leaving them red, itchy and burning. Inhaling the toxic steam can aggravate the sinuses and lungs. Chloramines, although a more stable compound, contains chlorine and ammonia and is also used to control bacteria in water systems. Its harmful effects cause the same dangers as pure chlorine.
Ascorbic acid reduction of residual
active chlorine in potable water prior to halocarboxylate determination In studies on the formation of disinfection byproducts
(DBPs), it is necessary to scavenge residual active (oxidizing) chlorine in
order to rx the chlorination byproducts (such as haloethanoates) at a point in
time. Such research projects often have distinct needs from requirements for
regulatory compliance monitoring. Thus, methods designed for compliance
monitoring are not always directly applicable, but must be adapted. This
research describes an adaptation of EPA Method 552 in which ascorbic acid
treatment is shown to be a satisfactory means for reducing residual oxidizing
chlorine, i.e., HOCl, ClO-, and Cl-2, prior to determining concentrations of
halocarboxylates. Ascorbic acid rapidly reduces oxidizing chlorine compounds,
and it has the advantage of producing inorganic halides and dehydroascorbic acid
as opposed to halogenated organic molecules as byproducts. In deionized water
and a sample of chlorinated tap water, systematic biases relative to strict
adherence to Method 552 were precise and could be corrected for using similarly
treated standards and analyte-fortified (spiked) samples. This was demonstrated
for the quantitation of chloroethanoate, bromoethanoate, 2,2-dichloropropanoate
(dalapon), trichloroethanoate, bromochloroethanoate, and bromodichloroethanoate
when extracted, as the acids, into tert-butyl methyl ether (MTBE) and esterified
with diazomethane prior to gas chromatography with electron capture detection
(GC-ECD). Recoveries for chloroethanoate, bromoethanoate, dalapon,
dichloroethanoate, trichloroethanoate, bromochloroethanoate,
bromodichloroethanoate, dibromoethanoate, and 2-bromopropanoate at
concentrations near the lower limit of detection were acceptable. Ascorbic acid
reduction appears to be the best option presently available when there is a need
to quench residual oxidants fast in a DBP formation study without generating
other halospecies but must be implemented cautiously to ensure no untoward
interactions in the matrix.
Many potable water disinfection byproducts (DBPs) that
result from the reaction of natural organic matter (NOM) with oxidizing chlorine
are known or suspected to be carcinogenic and mutagenic. The Ames assay is
routinely used to assess an overall level of mutagenicity for all compounds in
samples from potable water supplies or laboratory studies of DBP formation.
Reduction of oxidizing disinfectants is required since these compounds can kill
the bacteria or react with the agar, producing chlorinated byproducts. When
mutagens are collected by passing potable water through adsorbing resins, active
chlorine compounds react with the resin, producing undesirable mutagenic
artifacts. The bioanalytical and chemoanalytical needs of drinking water DBP
studies required a suitable reductant. Many of the candidate compounds failed to
meet those needs, including 2,4-hexadienoic (sorbic) acid, 2,4-pentanedione (acetylacetone),
2-butenoic (crotonic) acid, 2-butenedioic (maleic and fumaric) acids and
buten-2-ol (crotyl alcohol). Candidates were rejected if they (1) reacted too
slowly with active chlorine, (2) formed mutagenic byproducts, or (3) interfered
in the quantitation of known chlorination DBPs. L-Ascorbic acid reacts rapidly
and stoichiometrically with active chlorine and has limited interactions with
halogenated DBPs. In this work, we found no interference from L-ascorbic acid or
its oxidation product (dehydroascorbic acid) in mutagenicity assays of
chlorinated NOM using Salmonella typhimurium TA100, with or without metabolic
activation (S9). This was demonstrated for both aqueous solutions of chlorinated
NOM and concentrates derived from the involatile, ether-extractable chlorinated
byproducts of those solutions.
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