Mascara is a cosmetic commonly used to enhance eyelashes. It may darken, thicken, lengthen, and/or define the eyelashes. Normally in one of three forms - liquid, powder, or cream - the modern mascara product has various formulae; however, most contain the same basic components of pigments, oils, waxes, and preservatives. The most common form of mascara is a liquid in a tube.

Definition
The Collins English Dictionary defines mascara as "a cosmetic substance for darkening, lengthening, curling, coloring, and thickening the eyelashes, applied with a brush or rod". The Oxford English Dictionary (OED) adds that mascara is occasionally used on the eyebrows as well.

For darkening the eyebrow and mustaches without greasing them and making them prominent. 

Etymology
The source of the word "mascara" is unclear. The Spanish word máscara meaning ‘mask’ or ‘stain’, and the Italian word Maschera meaning 'mask' are possible origins. A related Catalan word describes soot or a black smear, and the Portuguese word máscara means ‘mask’ and mascara means dark stain or smut.

There is even strong support for a possible source from the Arabic word maskharah or 'buffoon'. 

History
Aesthetic adornment is a cultural universal and mascara can be documented in ancient Egypt. Records from around 4000 BC refer to a substance called kohl that was used to darken eyelashes, eyelids, and eyebrows. Kohl was used to masking the eyes, believed to ward off evil spirits and protect the soul, by both men and women. Often composed of galena; malachite; and charcoal or soot, crocodile stool; honey; and water was added to keep kohl from running. Though Egypt's influence, kohl usage persisted in the subsequent Babylonian, Greek, and Roman empires. Following the fall of the Roman Empire, kohl fell into disuse on the European continent, where it had been considered solely a cosmetic; conversely, it continued to be widely used in the Middle East for religious purposes.

During the Victorian Era, social opinion shifted radically towards the promotion of cosmetics, and women were known to spend a majority of their day occupied with beauty regimens. Great efforts were made to create the illusion of long, dark eyelashes. Attempting this, Victorian women made a type of mascara in their own homes. They would heat a mixture of ash or lampblack and elderberry juice on a plate and apply the heated mixture to their eyelashes.

The product that people would recognize as mascara today did not develop until the 19th century. A chemist named Eugine Rimmel developed a cosmetic using the newly invented petroleum jelly. The name Rimmel became synonymous with the substance and still translates to "mascara" in the Portuguese, Spanish, Greek, Turkish, Romanian, and Persian languages today.

Across the Atlantic Ocean and at roughly the same time, in 1915, Thomas Lyle Williams created a remarkably similar substance for his sister Mabel. In 1917 he started a mail-order business from the product that grew to become the company Mabelline.

The mascara developed by these two men consisted of petroleum jelly and coal in a set ratio. It was undeniably messy, and a better alternative was soon developed. A dampened brush was rubbed against a cake containing soap and black dye in equal proportions and applied to the lashes. Still, it was extremely messy. No significant improvement occurred until 1957 with innovation by Helena Rubinstein.

The events leading to Rubinstein's improvement began in Paris in the early 20the century. There, at the fashion capital of the world, mascara was quickly gaining popularity and common usage. Elizabeth Arden and Helena Rubinstein, two giants in the American beauty industry, watched and kept abreast of its development. After the first World War, American consumers became eager for new products. Sensing an opportunity, both Rubinstein and Arden launched their own brands of cosmetics which include mascara. Through the efforts of these two rivals and public temperament, mascara finally gained respect and favor in American Society.

The invention of the photograph and motion picture launched mascara's popularity and usage further forward. Motion pictures especially advertised a new standard of beauty and sex appeal. Famous actresses of the classic cinema era, such as Theda Bara, Pola Negri, Clara Bow, Greta Garbo, Marlene Dietrich, Bett Davis, and Jean Harlow, depended heavily upon mascara for their glamorized appearances, which the average women sought to mimic.

In 1933, a woman known on court records as Mrs. Brown consented to have her eyelashes permanently dyed. Unfortunately, the product, Lash Lure, used paraphenylenediamine, a chemical extremely toxic to the body, as the dyeing agent. At the time, cosmetics were unregulated by the Federal Drug Administration, and the dangers of the same were unknown. Within hours of treatment, Mrs. Brown began experiencing severe symptoms of stinging and burning eyes. By the next morning, Mrs. Brown's eyes had developed ulcers that oozed and had swollen shut. The use of Lash Lure resulted in blindness in Mrs. Brown and fifteen other women and also caused the death of another through bacterial infection. It was only after the Lash Lure incident and several others like it, documented in Ruth deFrost Lamb's book entitled American Chamber of Horrors, that Congress granted the Food and Drug Administration (FDA) the right to regulate cosmetics in 1938. 

Years later in 1957, Rubinstein created a formula that evolved mascara from a hard cake into a lotion-based cream. She packaged the new mascara in a tube to be sold with a brush. For use, the cream was squeezed onto the brush and applied to lashes. Although still messy, it was a step towards the modern mascara product.

Soon, a grooved rod was patented. The device picked up the same amount of mascara for each use. Then the grooved rod was altered to the brush similar to the ones used today. The change in applicator led mascara to be even easier to use, and its popularity increased.

Mascara is now trending towards multi-functional usage, with many mascaras including lash-boosting serums, botanicals, and pro-vitamin-enriched formulae. Korean technology is at the forefront of development, and a number of brands use tubing formulae to coat the lash.

Ingredients and Manufacture
All formulations contain pigments, oils, and waxes.

Cosmetic Pigments: The pigmentation for black mascara is similar to that used by the Egyptians and Victorian women. Black and brown mascaras typically are colored by the use of iron oxides. Some mascaras contain ultramarine blue. 

Mascara is composed of a base mixture of pigments, waxes, and oils with varying supporting components. Mascara pigments most commonly include iron oxides and titanium dioxide which provide mascara with its desired color. Titanium dioxide (TiO₂) accounts for over 65% of inorganic pigments sales volume. TiO₂ gives the pigment a white color while different iron oxides provide a variety of colors such as red, yellow, brown, and black. The particle size of opaque pigments ranges from 0.2-0.3  µm.

Oils, waxes, etc: Among the many oils used, linseed oil, castor oil, eucalyptus oil, lanolin, and oil of turpentine are found frequently. Sesame oil is also commonly used. Waxes usually found in mascara are paraffin wax, carnauba wax, and beeswax.

The desired effects of the mascara account for most variations of ingredients. Water-resistant mascaras require hydrophobic ingredients, like dodecane. Non-water-resistant mascaras have base ingredients that are water-soluble. Mascaras designed to lengthen or curl the eyelashes often contain nylon or rayon microfibers. Additionally, ceresin, gum tragacanth, and methylcellulose are regular ingredients and serve as stiffeners.

Manufacture: Mascara is often used on a daily basis around the world. In 2016, alone, US consumers spent 335.6 million USD on the top 10 leading mascara brands. 

In one method of production, referred to as anhydrous, all waxes, oils, and pigments are mixed, heated, and agitated simultaneously. The alternative method, termed emulsion, start by combining water and thickeners. Separately, waxes and emulsifiers are combined. The pigment is then added individually to both mixtures. Finally, all are combined in a homogenizer, which acts as a high-speed agitator in order to thoroughly mix the oils, water, waxes, and emulsifiers - ingredients that naturally repulse each other.

What is the shelf-life of mascara?
Mascara has a shelf life of two to four months.

Safety
Eye cosmetics containing kohl, al-kahal, tiro, tozali, or kwalli often pose a lead poisoning risk. In India, Kajal and Surma are used widely and there is not much information about lead poisoning. In the USA, Kajal and Surma, etc are illegal color additives.

It is more common to develop a stye, or commoner still, swollen eyelids. Styes and swollen eyelids are better classified as allergic reactions. The allergic reactions can be stimulated by any of the components of mascara but are usually attributed to methylparaben, aluminum powder, ceteareth-20, butylparaben, or benzyl alcohol.

If not cleaned properly, mascara can deposit itself under the conjunctiva in form of black lumps.

References;
1. Mascara