Bleaching of hair

Repeated exposure of dogs to 7 ppm for 6 months caused sneezing, lacrimation, and bleaching of hair at autopsy, there was local atelectasis. ... 

Cystine, which contains a disulfide bond, is reported to be the most numerous and reactive amino acid present in hair keratin. Disulfide bonds in cystine are reduced by mercaptans and phosphines, and oxidized by perborates, bromates, and bleach. These reactions result in structural rearrangements within keratin which may affect the physiochemical properties of hair, since disulfide bonds in cystine contribute to the stability of hair. For example, hydrogen peroxide bleaching of hair is an oxidative process which occurs readily in an alkaline medium. This results in the formation of perhydroxy anions which have been proposed to react with cystine to form cysteic acid residues. The process of bleaching results in the loss of approximately 15% of the cystine bonds originally present in keratin and may explain the increased permeability of bleached hair to chemicals. - ... 

Bleiberg J, Brodkin RH, Abbey AA. Bleaching of hair after... 

Doses of chloroquine used for oral therapy of the acute malarial attack may cause GI upset, headache, visual disturbances, and urticaria. Pruritus also occurs, most commonly among dark-skinned persons. Prolonged medication with suppressive doses occasionally causes side effects such as headache, blurring of vision, diplopia, confusion, convulsions, lichenoid skin eruptions, bleaching of hair, widening of the QRS interval, and T-wave abnormalities. These complications usually disappear soon rffter the drug is withheld. Rare instances of hemolysis and blood dyscrasias have been reported. Chloroquine may cause discoloration of nail beds and mucous membranes. 

HEALTH SYMPTOMS inhalation (irritates eyes, nose and throat) contact (blistering of the skin, skin reddening, bleaching of hair, comeal ulceration). 

ACUTE HEALTH RISKS irritation of eyes, nose, and throat erythema comeal ulceration vesicles on skin bleaching of hair irritating to body tissue. 

Concentrated solutions of hydrogen peroxide are very caustic and can cause bums of skin and mucous membranes. Exposure to its vapors can produce body irritation, lacrima-tion, sneezing, and bleaching of hair. A dose of 500 mg/kg by dermal route caused convulsions and deaths in rabbits. The oral LD50 value for 90% peroxide solution in mice is 2000 mg/kg. 

Chow [28] has provided evidence for penetration of the lower-molecular-weight PEI-6 into hair, and Woodard [42] has shown that sorption increases with concentration and with bleaching of hair similar to polymer JR. 

Hoeffkes, H. Gross, W. Hair dyes containing sUylcarbonates and/or syUlcarbamates for simultaneous dying and bleaching of hair. Ger. Offen. DE 102004052060,2006 Chem. Abstr. 2006,144,419031. 

Reactions involving the transfer of electrons are called oxidation-reduction reactions or redox reactions. Redox reactions are responsible for the rusting of iron, the bleaching of hair, and the production of electricity in batteries. Many redox reactions involve the reaction of a substance with oxygen. 

Oxidation and Reduction Redox reactions are common in nature, in industry, and in many everyday processes. Batteries use redox reactions to generate electrical current. Our bodies use redox reactions to obtain energy from glucose. In addition, the bleaching of hair, the rusting of iron, and the electroplating of metals all involve redox reactions. 

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