Special considerations in eye cosmetics

Millions of individuals worldwide regularly use cosmetics, personal care items, and tattoos. Tattoo ink and other makeup cosmetics also contain potentially toxic heavy metals. Heavy metals may build in the body after prolonged exposure. Most of them, including Pb, Cd, Hg, As, and Sb, are carcinogenic, allergenic, neurotoxic, teratogenic, and mutagenic contributing to hair loss and other cosmetic issues.

Despite of numerous researches around the world and regulations on cosmetic items in developed countries to determine safe levels of heavy metals, most consumers have not knowledge enough about the related risks, especially in developing nations where equivalent regulations are absent. In addition, everyday discarded cosmetics by customers pollute the environment, pose threats to microbes, plants, and animals, and are found in the solid waste and wastewater created by the cosmetic business. For these reasons, research, analytical analysis, publishing, surveying, reviewing and enhancing consumers' understanding of current laws, regulations, legislation, and recommendations of the U.S. Food and Drug Administration (US FDA), World Health Organization (WHO), U.S. Environmental Protection Agency (US EPA), and others are all necessary to raise public awareness about the hazards posed by heavy metals.

The current mini-review aims to summarize cosmetics and tattoos' historical background and development, focusing on their hazardous ingredients, health impact, and allowable levels of heavy elements according to regulations.

In this report the use of eye cosmetic products and procedures and how this represents a lifestyle challenge that may exacerbate or promote the development of ocular surface and adnexal disease is discussed. Multiple aspects of eye cosmetics are addressed, including their history and market value, psychological and social impacts, possible problems associated with cosmetic ingredients, products, and procedures, and regulations for eye cosmetic use. In addition, a systematic review that critically appraises randomized controlled trial evidence concerning the ocular effects of eyelash growth products is included. The findings of this systematic review highlight the evidence gaps and indicate future directions for research to focus on ocular surface outcomes associated with eyelash growth products.

An innovative and simple single drop ionic liquid based non-dispersive microextraction (SDILNDµE) method has been proposed for enrichment of arsenic (As), cadmium (Cd), nickel (Ni) and lead (Pb) in eye makeup products prior to analysis with electrothermal atomic absorption spectrometry (ETAAS). A narrow glass column was used to provide more contact area by enhancing the phase transfer ratio between two media (extractive and aqueous). Improved recoveries of the hydrophobic complexes of metals and metalloid with ammonium pyrrolidinedithiocarbamate (APDC) extracted into the 1-butyl-3-methylimidazolium hexafluorophosphate [C₄mim] [PF₆] were achieved. Several parameters were systematically optimized. At optimum conditions, limit of detection (LOD) for Cd, As, Pb and Ni was attained as 0.086, 0.049, 0.126 and 0.262 μgL⁻¹, correspondingly with relative standard deviation < 5%. Spike recovery study was carried out in the real samples to check the precision of proposed methodology. The proposed method was productively practiced on the real sample for simultaneous enrichment of toxic elements (As, Ni, Pb and Cd) in eye makeup products. Principal component analysis (PCA) was applied to assess the various levels of toxic elements as chief causes of variation in the data sets and to find the relation among samples (eye makeup products) and toxic elements (variables). Hierarchical cluster analysis (HCA) was used to explore the grouping of various eye makeup products on the basis of toxic element contents as additional statistics to the output attained by PCA.

The daily use of cosmetics may expose consumers to localized skin problems and systemic effects caused by absorption of chemical elements. The requirements for suitable quality control and maximum limits for toxic and potentially toxic elements in cosmetics have attracted the attention of the scientific community and of the official institutions around the world. Maximum limits for chemical elements in some cosmetics have been set, but there are disagreements between them. In the same context, many analytical methods have been proposed in the literature, but several challenges during the sample preparation and determination steps related to the high complexity of cosmetics’ matrices composition still remain. It is extremely difficulty to establish suitable methods, free of interference, even using modern technology. In this review, methods for determining toxic and potentially toxic elements in cosmetics used for make-up on the lips and on the eye area, covering the period since 2000, are presented. Techniques enabling direct analysis and those requiring a sample preparation step prior to the analysis are also discussed. This review focused on cosmetics for make-up on the lips and on the eye area because the risks of percutaneous absorption and oral ingestion of toxic and potentially toxic elements is higher than in other body regions.

To compare the effects on tear film parameters and contamination in cosmetic eyeliner wearers, after single application of two lipid-based dry eye treatments: a lipid-containing lubricant eye drop and a phospholipid liposomal spray.

Fifty participants were enrolled in a prospective, randomised, paired-eye, investigator-masked trial. Pencil eyeliner (Body Shop^® Crayon Eye Definer) was applied to the upper eyelid periocular skin of both eyes, anterior to the lash line. Baseline tear film quality was assessed fifteen minutes after eyeliner application. A lubricant drop (Systane^® Balance) was then applied to one eye (randomised), and liposomal spray (Tears Again^®) to the contralateral eye. Tear film contamination, lipid layer grade, non-invasive tear film break-up time and tear evaporation rate were evaluated fifteen minutes post-treatment and compared to pre-treatment values.

Pre-treatment measurements did not differ between eyes assigned to lubricant drop and liposomal spray. Tear film contamination was observed in a greater proportion of eyes following both treatments (both p < 0.05), with no significant difference between treatments (p = 0.41). Both treatments improved lipid layer thickness (both p ≤ 0.01), but effected no significant change in non-invasive tear film break-up time or tear evaporation rate (all p > 0.05). Changes in tear film parameters did not differ between treatments (all p > 0.05).

Both the lipid-containing lubricant eye drop and phospholipid liposomal spray result in clinically apparent tear film contamination in eyeliner cosmetic wearers. Although both treatments effected an increase in lipid layer thickness, neither displayed clinical efficacy in improving tear film stability.

The primary role of eyelashes is to protect and maintain the health of the lid margin. However, the mechanisms to fulfill this role are not fully understood. Unraveling these mechanisms will stand to greatly improve the efficiency of eye care professionals’ interventions in anomalies of the eyelashes. The aim of this article is to provide a review on eyelashes including highlights and new avenues for research; the biology of both the lash and its follicle; the pathophysiology and management of lash anomalies by eye care professionals; and the effect of iatrogenic factors on lashes. Using the database of Ovid MEDLINE, we reviewed studies specifically directed on human/mammalian eyelashes and key articles on current trends in scalp hair methodologies that can be applicable to lash research. The eyelash morphology, pigmentation and growth rate have been documented using techniques ranging from lash imaging to follicle immunohistochemistry. Furthermore, studies have demonstrated that the lash follicle is sensitive to many factors of the external environment, a variety of systemic/topical medications and cosmetics. Recently, aerodynamic studies using a mammalian eye model confirmed that an optimal lash length was needed so that eyelashes serve a protective role in reducing the number of particles that can reach the eye. Despite recent advances in lash research, studies are still scarce, due to the limited availability of the human lid for sampling. This review brings awareness that further research is needed with respect to eyelashes and will hopefully reduce the gap with scalp hair research.

La función principal de las pestañas es proteger y mantener la salud del margen palpebral. Sin embargo, los mecanismos de desempeño de esta función no se comprenden plenamente. Desentrañar estos mecanismos ayudará a mejorar la eficiencia de las intervenciones de los profesionales de cuidados oculares en cuanto a las anomalías de las pestañas. El objetivo de este artículo es aportar una revisión sobre las pestañas, incluyendo los aspectos más destacados y las nuevas aportaciones para la investigación, la biología de la pestaña y su folículo, la patofisiología y tratamiento de las anomalías de las pestañas por parte de los profesionales de cuidados oculares, y el efecto de los factores iatrogénicos sobre las pestañas. Utilizando la base de datos de Ovid MEDLINE, revisamos los estudios específicamente dirigidos a las pestañas humanas/de mamíferos, así como los artículos clave sobre las tendencias actuales en cuanto a las metodologías del cuero cabelludo, que pueden aplicarse a la investigación sobre las pestañas. Se han documentado la morfología de las pestañas, así como su pigmentación y tasa de crecimiento, utilizando técnicas que oscilan entre la imagen de las pestañas y la inmunohistoquímica del folículo. Además, los estudios han demostrado que el folículo de la pestaña es sensible a diversos factores del entorno externo, diversas medicaciones sistémicas/tópicas y cosméticos. Recientemente, los estudios aerodinámicos que han utilizando un modelo de ojo de mamífero, han confirmado que se precisaba una longitud de pestañas óptima para que éstas ejercieran su función protectora a la hora de reducir el número de partículas que pueden acceder al ojo. A pesar de los avances recientes de la investigación sobre las pestañas, los estudios son aún escasos, debido a la disponibilidad limitada de párpado humano para muestreo. Esta revisión sirve de concienciación acerca de la necesidad de investigación futura con respecto a las pestañas, que reducirá presumiblemente la brecha existente con respecto a la investigación sobre el cuero cabelludo.