Hair coloring – Wikipedia

Hair coloring - Wikipedia

A hairdresser colours a consumer’s hair.

Hair coloring, or hair dyeing, is the follow of adjusting the hair coloration. The primary causes for this are beauty: to cowl grey or white hair, to vary to a coloration considered extra modern or fascinating, or to revive the unique hair coloration after it has been discolored by hairdressing processes or solar bleaching.

Hair coloring will be accomplished professionally by a hairdresser or independently at residence. At present, hair coloring may be very in style, with 75% of girls[1] and 18% of males residing in Copenhagen having reported utilizing hair dye (in response to a research by the College of Copenhagen). At-home coloring in america reached $1.9 billion in 2011 and was anticipated to rise to $2.2 billion by 2016.

Historical past[edit]

Diodorus Siculus, a Greek historian, described intimately how Celtic individuals dyed their hair blonde:
“Their side is terrifying… They’re very tall in stature, with rippling muscle tissue underneath clear white pores and skin. Their hair is blond, however not naturally so: they bleach it, to at the present time, artificially, washing it in lime and brushing it again from their foreheads. They appear to be wood-demons, their hair thick and shaggy like a horse’s mane. A few of them are clean-shaven, however others—particularly these of excessive rank—shave their cheeks however depart a moustache that covers the entire mouth…”.[2][3]

The dyeing of hair is an historic artwork that includes remedy of the hair with numerous chemical compounds. In historic occasions, the dyes have been obtained from vegetation.[4] A number of the most well-known are henna (Lawsonia inermis), indigo, Cassia obovata, senna, turmeric and amla. Others embody katam (buxus dioica), black walnut hulls, purple ochre and leeks.[5] Within the 1661 e book Eighteen Books of the Secrets and techniques of Artwork & Nature, numerous strategies of coloring hair black, gold, inexperienced, purple, yellow, and white are defined.[6] The event of artificial dyes for hair is traced to the 1860s discovery of the reactivity of para-phenylenediamine (PPD) with air.[7]Eugène Schueller, the founding father of L’Oréal, is acknowledged for creating the primary artificial hair dye in 1907.[8] In 1947 the German cosmetics agency Schwarzkopf launched the primary residence coloration product, “Poly Colour”.[9] Hair dyeing is now a multibillion-dollar {industry} that includes using each plant-derived and artificial dyes.[10]

Utility strategies[edit]


Hair with blonde highlights

Hair coloration was historically utilized to the hair as one general coloration. The trendy development is to make use of a number of colours to supply streaks or gradations, however not all work on high of a single base coloration. These are known as:

  • Highlighting, the place sections of hair are handled with lighteners
  • Lowlighting, the place sections of hair are handled with darker hair colours
  • Splashlighting a horizontal band of bleached hair from ear to ear

There are additionally newer coloring strategies comparable to ombré, shatush, balayage, airtouch, by which hair is darkish on the crown and little by little turns into lighter towards the ends.

These are off-the-scalp strategies, and will be utilized by the next strategies:

  • Foiling, the place items of foil or plastic movie are used to separate the hair to be coloured, particularly when making use of multiple coloration (This ensures the colour is utilized solely to the specified strands of hair, and protects the strands of hair not supposed to be dyed.)
  • Cap, when a plastic cap is positioned tightly on the pinnacle and strands are pulled by means of with a hook (This methodology shouldn’t be regularly practiced, excluding highlighting brief hair.)
  • Balayage, the place hair coloration is painted immediately onto sections of the hair with no foils used to maintain the colour contained (This methodology is rising in recognition due to its potential to look extra pure.) The distinction between balayage and ombré is {that a} balayage requires extra exact hand-painting sections of hair and usually prices extra.
  • Dipping or tip dyeing, much like balayage in that the colour is painted immediately on the hair (This leads to a extra stable degree of protection on the ends of the hair.)[11]

All coloring strategies can be utilized with any sort of coloration. For lightening, the hair generally needs to be bleached earlier than coloring.


Hair coloring will also be utilized on the scalp for a extra stable degree of protection

  • Root touch-up, the place coloration is utilized solely to the latest part of re-growth (normally the primary inch of hair nearest the scalp) Root touch-ups are repeated each 4–6 weeks because the pure coloration grows in and turns into obvious. Individuals who coloration their hair to disguise grey typically have these root touch-ups.
  • All-over coloration, the place the particular person needs all of their hair to be a special stable coloration
  • Block coloring, the place the particular person needs two or extra colours utilized to their hair, leading to dimension and distinction

All coloring strategies can be utilized with any sort of coloration. For lightening, the hair generally needs to be bleached earlier than coloring.

The 4 most typical classifications are everlasting, demi-permanent (generally known as deposit solely), semi-permanent, and momentary.[7]


Everlasting hair coloration typically comprises ammonia and should be combined with a developer or oxidizing agent with a view to completely change hair coloration. Ammonia is utilized in everlasting hair coloration to open the cuticle layer in order that the developer and colorants collectively can penetrate into the cortex.[12] The developer, or oxidizing agent, is available in numerous volumes. The upper the developer quantity, the upper the “elevate” will likely be of an individual’s pure hair pigment. Somebody with darkish hair wishing to attain two or three shades lighter might have the next developer whereas somebody with lighter hair wishing to attain darker hair is not going to want one as excessive. Timing could range with everlasting hair coloring however is usually 30 minutes or 45 minutes for these wishing to attain most coloration change.


Demi-permanent hair coloration is hair coloration that comprises an alkaline agent apart from ammonia (e.g. ethanolamine, sodium carbonate) and, whereas at all times employed with a developer, the focus of hydrogen peroxide in that developer could also be decrease than used with a everlasting hair coloration. Because the alkaline brokers employed in demi-permanent colours are much less efficient in eradicating the pure pigment of hair than ammonia these merchandise present no lightening of hair’s coloration throughout dyeing. Because the outcome, they can’t coloration hair to a lighter shade than it was earlier than dyeing and are much less damaging to hair than their everlasting counterpart.

Demi-permanents are rather more efficient at protecting grey hair than semi-permanents, however much less so than permanents.

Demi-permanents have a number of benefits as in contrast with everlasting coloration. As a result of there may be primarily no lifting (i.e., elimination) of pure hair coloration, the ultimate coloration is much less uniform/homogeneous than a everlasting and due to this fact extra pure wanting; they’re gentler on hair and due to this fact safer, particularly for broken hair; they usually wash out over time (usually 20 to 28 shampoos), so root regrowth is much less noticeable and if a change of coloration is desired, it’s simpler to attain. Demi-permanent hair colours aren’t everlasting however the darker shades particularly could persist longer than indicated on the packet.


Semi-permanent hair coloring includes little or no developer, hydrogen peroxide or ammonia, and is thus much less damaging to hair strands. The diminished quantity of developer, whether or not peroxide or ammonia, implies that hair beforehand broken by making use of everlasting coloration or everlasting reshaping is much less prone to be broken in the course of the coloration utility course of.

Semi-permanent hair coloration makes use of compounds of decrease molecular weight than are present in momentary hair coloration dyes. These dyes penetrate the hair shaft solely partially, due to the diminished quantity of developer used. For that reason, the colour will survive repeated washing, usually 4–5 shampoos or a number of weeks, earlier than present process vital fading or washing out totally.

Semi-permanents should still include the suspected carcinogen p-phenylenediamine (PPD) or different associated colorants. The U.S. Environmental Safety Company reported that in rats and mice chronically uncovered to PPD of their food plan, the PPT seems to easily depress physique weight of the animals, with no different scientific indicators of toxicity noticed in a number of research.[13]

The ultimate coloration of every strand of hair will depend upon its authentic coloration and porosity. As a result of hair’s coloration and porosity throughout the pinnacle and alongside the size of a hair strand, there will likely be delicate variations in shade throughout your entire head. This offers a extra natural-looking outcome than the stable, throughout coloration of a everlasting coloration. As a result of grey or white hairs have a special beginning coloration than different hair, they won’t seem as the identical shade as the remainder of the hair when handled with semi-permanent coloration. If there are just a few gray/white hairs, the impact will normally be sufficient for them to mix in, however as the grey spreads, there’ll come a degree the place it is not going to be disguised as nicely. On this case, the transfer to everlasting coloration can generally be delayed by utilizing the semi-permanent as a base and including highlights.

Semi-permanent coloration can not lighten the hair.

Short-term coloration[edit]

Short-term hair coloration is on the market in numerous kinds together with rinses, shampoos, gels, sprays, and foams. Short-term hair coloration is usually brighter and extra vibrant than semi-permanent and everlasting hair coloration. It’s most frequently used to paint hair for particular events comparable to costume events and Halloween.

The pigments in momentary hair coloration are excessive molecular weight and can’t penetrate the cuticle layer. The colour particles stay adsorbed (intently adherent) to the floor of the hair shaft and are simply eliminated with a single shampooing. Short-term hair coloration can persist on hair that’s excessively dry or broken in a approach that enables for migration of the pigment to the inside of the hair shaft.

Different coloration[edit]

Hair and beard coloured blue

Different hair coloring merchandise are designed to create hair colours not usually present in nature. These are additionally known as “vivid coloration” within the hairstyling {industry}. The out there colours are numerous, comparable to the colours inexperienced and fuchsia.
Everlasting options in some colours can be found. Extra lately, blacklight-reactive hair dyes have been delivered to market that fluoresce underneath blacklights, comparable to these typically used at nightclubs.

The chemical formulae of other coloration dyes usually include solely tint and haven’t any developer. Which means they are going to solely create the intense coloration of the packet if they’re utilized to mild blond hair. Darker hair (medium brown to black) would must be bleached to ensure that these pigment purposes to take to the hair desirably. Some sorts of honest hair might also take vivid colours extra totally after bleaching. Gold, yellow and orange undertones in hair that has not been lightened sufficient can muddy the ultimate hair coloration, particularly with pink, blue and inexperienced dyes. Though some different colours are semi-permanent, comparable to blue and purple, it may take a number of months to totally wash the colour from bleached or pre-lightened hair.

Sustaining hair coloration[edit]

There are a lot of ways in which individuals can keep their hair coloration, comparable to:

  • Utilizing color-protecting shampoos and conditioners
  • Utilizing sulfate-free shampoo
  • Utilizing purple shampoos and conditioners to take care of or improve the blond coloration of their hair
  • Utilizing leave-in therapies with UV absorbents
  • Getting deep-conditioning therapies to easy and add luster
  • Avoiding chlorine
  • Utilizing warmth defending merchandise earlier than utilizing styling home equipment

Hostile results[edit]

Hair coloring includes using chemical substances able to eradicating, changing, and/or protecting up pigments naturally discovered contained in the hair shaft. Use of those chemical substances may end up in a spread of adversarial results, together with momentary pores and skin irritation and allergy, hair breakage, pores and skin discoloration and surprising hair coloration outcomes. In line with the Worldwide Company for Analysis on Most cancers (IARC), in vitro and in vivo research (in uncovered human populations) have proven that some hair dyes and lots of chemical substances used within the hair dyeing course of will be thought of mutagenic and carcinogenic.[14][15]

Pores and skin irritation and allergy[edit]

In sure people, using hair coloring may end up in allergic reactions and/or pores and skin irritation. People allergic to gluten for instance, will must be cautious when buying hair coloration since sure hair dye contains gluten. Gluten doesn’t must be ingested for it to trigger an allergy. Pores and skin contact with gluten could trigger a response; due to this fact, resulting in an allergy. Signs of those reactions can embody redness, sores, itching, burning sensation and discomfort. Signs will generally not be obvious instantly following the applying and processing of the tint, however may also come up after hours or perhaps a day later.

To assist stop or restrict allergic reactions, nearly all of hair coloration merchandise suggest that the consumer conduct a patch take a look at earlier than utilizing the product. This includes mixing a small amount of tint preparation and making use of it on to the pores and skin for a interval of 48 hours. If irritation develops, producers suggest that the consumer not use the product.

European dermatologists have, nevertheless, strongly suggested towards such pre-use testing, because it entails further sensitisation (allergy) danger and the interpretation by lay individuals is probably not sufficiently correct.[16]

Pores and skin discoloration[edit]

Pores and skin and fingernails are fabricated from an identical sort of keratinized protein as hair. That implies that drips, slips and further hair tint across the hairline may end up in patches of discolored pores and skin. That is extra frequent with darker hair colours and individuals with dry absorbent pores and skin. That’s the reason it is suggested that latex or nitrile gloves be worn to guard the fingers.

This discoloration will disappear because the pores and skin naturally renews itself and the highest layer of pores and skin is eliminated (usually takes a number of days or at most every week). Methods of stopping pores and skin discoloration are to put on latex or nitrile gloves to guard the fingers and in addition by making use of a skinny layer of petroleum jelly or oil-based preparation across the hairline. Light abrasives comparable to moist baking soda or a small quantity of toothpaste utilized with a toothbrush might also assist take away the uppermost layer of pores and skin and dye (neither removes simply the dye). Acetone and nail polish remover aren’t thought of efficient; laundry detergent could generally work as could moist cigarette ash rubbed into the stained space.[17]

Unintended outcomes[edit]

A number of components affect the ultimate coloration of the hair following the coloring course of.

  • For semi-permanent and demi-permanent coloration, the ultimate coloration is a mix of the pure coloration of the hair and the dye coloration.
  • Bleached hair will typically require pre-pigmentation earlier than a coloration utility. Dyeing bleached hair brown may end up in gray or very ashy (gray sheen) hair.
  • Beforehand coloration handled hair can react unpredictably with subsequent coloration therapies.
  • Earlier use of shampoos which deposit a layer of plastic on the hair can block the motion of the dye.
  • Presence of minerals, salts, chlorine or different contaminants within the water used within the coloring course of
  • Sure prescribed drugs can alter hair chemistry
  • Coloring darkish hair to attain a fascinating shade of blond requires bleaching, adopted by a secondary coloration remedy. Bleached hair can nonetheless have a yellow or coppery shade. A violet-based coloration can cancel out yellow tones, and a blue-based shade will cancel out coppery orange.
  • Porosity of hair can have an effect on the ultimate shade. Porous hair typically absorbs extra coloration, which generally outcomes darker than anticipated

Well being issues[edit]

  • The salt lead acetate (the lively ingredient in gradual darkening merchandise comparable to Grecian method) is poisonous.[18][19][20] Lead acetate trihydrate has additionally been proven to trigger reproductive toxicity.[21]
  • Articles hyperlink the event of some types of most cancers (together with leukemia, non-Hodgkin’s lymphoma, bladder most cancers, blood most cancers, and a number of myeloma) with use of hair coloration.[22][23] Extra particularly, extended use of everlasting darkish hair dyes can double an individual’s danger of getting some sorts of blood most cancers.[24]
  • In 2004 a recognized human carcinogen, 4-aminobiphenyl or 4-ABP, was present in some business hair dyes.[24] Nevertheless, proof is proscribed and inconsistent for the hyperlink between most cancers from hair dye.[25]
  • Phenylenediamine is understood to trigger well being issues, comparable to pores and skin irritation. Publicity to phenylenediamine can happen throughout manufacturing or throughout using hair dyes. In line with the Product Security Abstract Sheet by DuPont, Para-Phenyenediamine (PPD) is labeled as poisonous and may trigger adversarial results on aquatic organisms and will trigger long-term results in aquatic environments.[26]

In October 2017, the main breast surgeon Professor Kefah Mokbel revealed a meta-analysis displaying that use of hair dyes may enhance the danger of creating breast most cancers by 20% amongst customers.[27]

Chemistry of everlasting hair coloring[edit]

Everlasting hair coloring requires three parts: (1) 1,4-diaminobenzene (traditionally) or 2,5-diaminotoluene (at the moment), (2) a coupling agent, and (3) an oxidant. The method is usually carried out underneath primary situations. The mechanism of oxidation dyes includes three steps:[7]
1) Oxidation of 1,4-diaminobenzene spinoff to the quinone state.
2) Response of this diimine with a coupler compound (extra element under).
3) Oxidation of the ensuing compound to provide the ultimate dye.

The preparation (dye precursors) is within the leuco (colorless) kind. Oxidizing brokers are normally hydrogen peroxide, and the alkaline setting is normally offered by ammonia. The mix of hydrogen peroxide and ammonia causes the pure hair to be lightened, offering a “clean canvas” for the dye. Ammonia opens the hair shaft pores in order that the dye can truly diffuse contained in the fiber. These dye intermediates and coupler compounds can bear oxidation and coupling response as proven within the scheme under to kind excessive molecular weight merchandise, that are trapped within the hair matrix and can’t be readily eliminated by means of washing.

Numerous combos of main intermediates and coupler compounds present a spectrum of shades of hair colours. The first intermediates are fragrant para compounds, comparable to 1,4-diaminobenzene or 4-aminophenol. The coupler compounds (couplers) are meta-substituted derivatives of aniline. They arrive in three main lessons based mostly on the colour that they produce once they react with the first intermediate.

Couplers are chemical compounds that outline the colour of the hair dye. Proven listed below are three purple couplers (A, B, C), two yellow-green couplers (D, E) and a blue coupler (F).
  • Blue couplers embody 1,3-diaminobenzene and its derivatives.
  • Purple couplers embody phenols and naphthols, comparable to 3-aminophenol (CAS#591-27-5), 5-amino-2-methylphenol (CAS#2835-95-2) and 1-naphthol (CAS#90-15-3). The mix of two,5-diaminotoluene with the coupler 3-aminophenol provides a magenta-brown dye, whereas the mix of two,5-diaminotoluene with the coupler 1-naphthol provides a purple dye.
  • Yellow-green couplers embody resorcinol, 4-chlororesorcinol, and benzodioxoles. These compounds produce broad-band absorption once they react to kind dyes, permitting for extra natural-looking hair colours. The mix of two,5-diaminotoluene with the coupler resorcinol provides a greenish brown dye.

Step one exhibits the oxidation of p-phenylenediamine to the quinonediimine (C6H4(NH)2):


This species exists in equilibrium with the monoprotonated kind (C6H4(NH)(NH2)+) (not proven). The second step includes the assault of this quinonediimine on the coupler. In natural chemistry, this response is named electrophilic fragrant substitution:


Within the third and remaining step, the product from the quinonediimine-coupler response oxidizes to the ultimate hair dye.


It was as soon as believed that the dye kinds within the above response bonds to hair completely.[7] It was later proven that the primary motive that this response imparts a everlasting coloration on hair is that it produces bigger dye molecules, which is locked contained in the hair.[28]

Plant-based dyes[edit]

Henna is an orange dye generally used as a deposit-only hair coloration whose lively element, lawsone, binds to keratin. It’s due to this fact thought of semi-permanent to everlasting, relying on an individual’s hair sort. Most individuals will obtain a everlasting coloration from henna, particularly after the second dye. With repeated use the orange coloration builds up into purple after which auburn. Whereas “pure” henna is usually a purple coloration, variations exist. These variations normally include substances from different vegetation and even artificial dyes.

Indigo is pure dye from a plant (Indigofera tinctoria, suffructicosa, or arrecta) that may be added to henna or layered on high of it to create brown to black colours within the hair. Henna is orange, and indigo is blue, in order complementaries on a normal coloration wheel, the 2 colours’ mixed impact is to create brown tones. Like henna, indigo could fade after one utility, nevertheless it turns into everlasting on the hair with repeated use.

Utilizing a plant-based coloration comparable to henna could cause issues later when attempting to do a perm or everlasting hair coloration. Some store-bought henna comprises metallic salts which reacts to hydrogen peroxide that’s utilized in hair lightening. This may increasingly result in unpredictable outcomes, comparable to inexperienced or blue tones within the hair. Henna is a wholesome solution to coloration hair, so long as no metallic salts are used.

In 2018, a system for making semi-permanent hair dyes from renewable waste blackcurrant (Ribes nigrum L.) fruit skins from the fruit urgent {industry} was developed. Anthocyanin pigments have been extracted from the blackcurrant pores and skin waste[29] and formulated into hair dyes. The dyes confirmed excessive buildup on hair and gave an intense blue coloration, which was steady to a number of washes.[30]

Authorized restrictions[edit]

Hair dyes are beauty compounds that make contact with the pores and skin throughout utility. Due to this pores and skin contact, there exists some well being danger related to use of hair dyes.[31] Thus, hair dyes are regulated within the business market and, as new toxicity information is generated for some hair dyes and well being dangers are found, a few of these hair dyes are being legally restricted from the beauty market.

The European Union is especially stringent with regard to well being rules. To make sure that hair dyes include solely protected substances, the European Fee adopted the Directive 2012/21/EU to limit using round 45 chemical substances in hair dyes.[32] The directive on dyes is a part of a common and complete set of rules, the EU Cosmetics Directive 76/768/EC.


For Muslims, if a person shouldn’t be of superior age, there isn’t a hurt in his utilizing black dye. A number of the early Muslims, together with some sahabah, permitted using black dye.[33] As narrated in a hadith, the perfect factor with which to dye grey hair is henna and katm (a plant from Yemen which colours it black tinged with purple).

See additionally[edit]


  1. ^ Vedel-Krogh, Signe; Nielsen, Sune F.; Schnohr, Peter; Nordestgaard, Børge G. (2016). “Morbidity and Mortality in 7,684 Girls In line with Private Hair Dye Use: The Copenhagen Metropolis Coronary heart Research adopted for 37 Years”. PLOS ONE. 11 (3): e0151636. Bibcode:2016PLoSO..1151636V. doi:10.1371/journal.pone.0151636. PMC 4795553. PMID 26986063.
  2. ^ “The Celts”. Retrieved 27 March 2018.
  3. ^ “Diodorus Siculus, Library of Historical past – Exploring Celtic Civilizations”. Retrieved 27 March 2018.
  4. ^ Corbett, J. F. Hair Colorants: Chemistry and Toxicology; Micelle Press: Dorset, U.Okay., 1998; Thompson, R. H. “Naturally Occurring Quinones” Tutorial Press: New York, 1957.
  5. ^ BBC. “BBC – Radio Four Girl’s Hour -The Historical past of Hair Dye”.
  6. ^ Wecker, Johann Jacob (1661). Eighteen Books of the Secrets and techniques of Artwork & Nature. pp. 82–84.
  7. ^ a b c d “Hair Preparations,” Ullmann’s Encyclopedia of Industrial Chemistry. Wiley-VCH, Weinheim (2006). doi:10.1002/14356007.a12_571.pub2
  8. ^ Pointer, Sally (Might 1, 2005). The Artifice of Magnificence: A Historical past and Sensible Information to Fragrance and Cosmetics. The Historical past Press. ISBN 978-0750938877.
  9. ^ “Schwarzkopf >COMPANY >Historical past Milestones of success”. Archived from the unique on 2015-02-17. Retrieved 2015-01-14.
  10. ^ Morel, Olivier J. X.; Christie, Robert M. (2011). “Present Traits within the Chemistry of Everlasting Hair Dyeing”. Chemical Critiques. 111 (4): 2537–2561. doi:10.1021/cr1000145. PMID 21265503.
  11. ^ Wilson, Cynthia (6 August 2012). “Dip-Dye Hair Coloring Tutorial and Kinds”. Womenio. Retrieved 6 October 2012.
  12. ^ “Hair Colour 101: Everlasting Hair Colour from Clairol Skilled”. Retrieved 2015-10-26.
  13. ^ p-Phenylenediamine, U.S. Environmental Safety Company
  14. ^ “IARC working group on the analysis of carcinogenic dangers to people: occupational exposures of hairdressers and barbers and private use of hair colorants; some hair dyes, beauty colorants, industrial dyestuffs and fragrant amines. Proceedings. Lyon, France, 6-13 October 1992”. IARC Monogr Eval Carcinog Dangers Hum. 57: 7–398. 1993. PMID 7911535.
  15. ^ IARC Monographs Working Group on the Analysis of Carcinogenic Dangers to, People (2010). “Some fragrant amines, natural dyes, and associated exposures”. IARC Monographs on the Analysis of Carcinogenic Dangers to People / World Well being Group, Worldwide Company for Analysis on Most cancers. 99: 1–658. PMC 5046080. PMID 21528837.
  16. ^ Thyssen, Jacob P.; Søsted, Heidi; Uter, Wolfgang; Schnuch, Axel; Giménez-Arnau, Ana M.; Vigan, Martine; Rustemeyer, Thomas; Granum, Berit; McFadden, John; White, Jonathan M.; White, Ian R.; Goossens, Ann; Menné, Torkil; Lidén, Carola; Johansen, Jeanne D. (2012). “Self-testing for contact sensitization to hair dyes – scientific concerns and scientific issues of an industry-led screening programme”. Contact Dermatitis. 66 (6): 300–311. doi:10.1111/j.1600-0536.2012.02078.x. PMID 22568836. S2CID 10022501.
  17. ^ Alexandra Tunell, How you can Get Hair Dye off Your Pores and skin, Harper’s Bazaar, Oct 2, 2016
  18. ^ “Family Merchandise Database – Well being and Security Info on Family Merchandise”. Retrieved 2017-02-12.
  19. ^ Riaz, Almas (29 Might 2016). “Shampoo for coloration handled hair”. Tune Your Hair. The Hair Laboratory. Retrieved 12 February 2017.
  20. ^ Tukker, Arnold; Buijst, Harrie; Van Oers, Lauren; Van Der Voet, Ester (2001). “Dangers to Well being and the Surroundings Associated to the Use of Lead in Merchandise” (PDF).
  21. ^ Lamb, James (Feb 1997). “Reproductive toxicology. Lead acetate trihydrate”. Environ Well being Perspect. 105: 315–316. doi:10.2307/3433461. JSTOR 3433461. PMC 1470238. PMID 9114341.
  22. ^ “Does hair dye trigger most cancers?”. Most cancers Analysis UK. 20 July 2006. Archived from the unique on 20 September 2007. Retrieved 29 July 2007.
  23. ^ DeNoon, Daniel J. (January 26, 2004). “Hair Dye Linked to Blood Most cancers: Lengthy-Time period Use of Darkish, Everlasting Dye Might Increase Lymphoma Danger”. Net MD. Retrieved 2007-07-29.
  24. ^ a b Hair Dye Linked to Blood Most cancers. Retrieved on 2010-12-21.
  25. ^ Hair Dyes and Most cancers Danger – Nationwide Most cancers Institute. Most (2009-10-09). Retrieved on 2010-12-21.
  26. ^ “Product Security Abstract Sheet DuPont™ P-Phenylenediamine. Rep. no. 106-50-3. N.p.: n.p., 2012”.
  27. ^ Gera, R.; Mokbel, R.; Igor, I.; Mokbel, Okay. (2018). “Does the Use of Hair Dyes Enhance the Danger of Growing Breast Most cancers? A Meta-analysis and Assessment of the Literature”. Anticancer Analysis. 38 (2): 707–716. doi:10.21873/anticanres.12276. PMID 29374694.
  28. ^ Alexander Chan, Sean Kung, (September, 2006), “Hair Colorant Know-how Advances Additional”, Private Care, p. 11-16
  29. ^ Farooque, Sannia; Rose, Paul M.; Benohoud, Meryem; Blackburn, Richard S.; Rayner, Christopher M. (2018). “Enhancing the Potential Exploitation of Meals Waste: Extraction, Purification, and Characterization of Renewable Specialty Chemical substances from Blackcurrants (Ribes nigrum L.)” (PDF). J. Agric. Meals Chem. 66 (46): 12265–12273. doi:10.1021/acs.jafc.8b04373. PMID 30412401.
  30. ^ Rose, Paul M.; Cantrill, Victoria; Benohoud, Meryem; Tidder, Alenka; Rayner, Christopher M.; Blackburn, Richard S. (2018). “Utility of Anthocyanins from Blackcurrant (Ribes nigrum L.) Fruit Waste as Renewable Hair Dyes” (PDF). J. Agric. Meals Chem. 66 (26): 6790–6798. doi:10.1021/acs.jafc.8b01044. PMID 29808681.
  31. ^ Maiti, Swati; Sinha, Sudarson; Singh, Mukesh (2015). “Hair Dye–DNA Interplay: Believable Explanation for Mutation”. Cosmetics. 2 (4): 313–321. doi:10.3390/cosmetics2040313.
  32. ^ “Fee implementing Directive 2012/21/EU”, Official Journal of the European Union, 2 August 2012, Retrieved 7 April 2015
  33. ^ al-Qaraḍāwī, Yūsuf (30 January 1999). The lawful and the prohibited in Islam : al-Halal wal-haram fil Islam. American Belief Publications. p. 93. ISBN 9780892590162.

Leave a Reply

Your email address will not be published. Required fields are marked *