Study method. We chose women as subjects because the main users of color makeup products are still female consumers and set a series of strict inclusion and exclusion criteria to obtain daily exposure scenarios12. The sample size of our study was 346, which was similar to the relevant studies in the United States and Japan12–15. With the rapid development of China's cosmetics industry, it has become the second-largest cosmetics consumer market in the world10. Given the target products, we selected 10 types of commonly used makeup products, including base makeup products with large areas and large amounts of use, eye makeup products that may cause eye irritation such as eyelid infection, corneal infection, dry eye syndrome, lip makeup products that may be caused by oral exposure, and cleaning and removing makeup products 4,9,22–24. Considering the scientific validity and validity of the survey, our use of a two-week diary completion time was relatively appropriate, which was similar to the studies in the United States, Korea, and the European Union9,13–16. Our project team let the subjects use their cosmetics to ensure that the subjects completed the survey according to their habits, which was consistent with the studies in the European Union, the Netherlands, and South Korea 9,16,18. For the recording method, online daily questionnaire recording was used in this study, which was more efficient and concise than home interviews, mail distribution, and telephone interviews. The total exposure obtained by weighing before and after the study was more objective and scientific than the visual inspection method and bar-code scanning method25. Age is one of the main parameters in cosmetic exposure studies. With age, skin conditions, beauty pursuits, and usage habits may differ. For example, the Korean study found that women in their 20s used lip gloss, lip balm, and lip balm significantly more often and in greater quantities. Women in their 30s used more eyeshadow, and women in their 50s used more mascara and lipstick9. Similarly, we found that the same exposure factors of color makeup products varied based on age. In addition, several studies have pointed out that face skin type and sensitive/non-sensitive skin are also important parameters of cosmetic exposure9,18. In this study, we also found similar findings in the mascara, powder base makeup, and lipstick categories.
Comparison with the previous study. Generally, in comparison with previous foreign research findings, the usage levels observed in this study are similar to those reported in Japan and South Korea. However, the daily frequency of cosmetic use among the Chinese population is lower, resulting in reduced overall usage. Furthermore, it should be noted that the amount of cosmetics used across all categories is significantly lower than that reported in both the European Union and the United States. The inclusion of both men and women in Biesterbos et al.'s study on Dutch individuals may have contributed to comparatively lower statistical outcomes. The comparison of use amount with the previous study is summarized in Table 8. The European Union has a relatively complete management system in terms of cosmetic safety evaluation. Among them, the SCCS is the most important technical support organization in this field. The "Notes of Guidance for Testing of Cosmetic Ingredients and Their Safety Evaluation by the SCCS" drafted and continuously updated by the SCCS summarizes the skin exposure area, retention coefficient, frequency of use, average daily use, average daily unit weight exposure, and other data of common adult cosmetic categories for industry reference to regulate the safety evaluation process of cosmetics. Comparing the P90 exposure data obtained in this study with SCCS’s, it was found that the parameters of the amount applied per application and day obtained in this study were much lower than the reference values of SCCS. The P90 of non-powder base makeup was 0.58 times that of SCCS, mascara was 0.56 times that of SCCS, lipstick was 0.21 times that of SCCS, and makeup remover was 0.58 times that of SCCS. However, the values currently used by the SCCS are the same for male and female consumers, and for adults and children.
Limitations. Our study was carried out during July 27-December 15,2022 and March 6-July 26,2023. Most of the work was carried out in 2022 when COVID-19 was prevalent, and people are accustomed to wearing masks when going out, which may reduce the possibility of people using makeup26. In addition, this study targeted women in Shanghai, while China is so vast that it can be further expanded in different cities to protect Chinese consumers more scientifically. Due to subject compliance and sample size, factors such as gender, education, occupation, and economic factors were not considered in this study. It can be further analyzed in a larger population study. For example, population studies in South Korea have found that men use some types of cosmetics more often than women and that cosmetics use patterns are closely related to socioeconomic factors3,9,18. With the development of the cosmetics industry, the categories of color cosmetics are more and more refined, which makes some color cosmetics with similar uses and textures have a certain substitution effect. Therefore, the research on the subdivision exposure of color cosmetics needs to be further deepened8. In addition, our current study focused on cosmetic exposure risk assessment for daily use scenarios. Studies in Japan have pointed out that there is a big difference between the outdoor and leisure use scenarios of sunscreen12. In the future, with the deepening of science, it is of great significance to comprehensively consider the type of cosmetics, use scenarios, use method, use site, use frequency, contact time, product ingredient concentration, and consumer target population to conduct targeted exposure scenario research to ensure the accuracy of cosmetic exposure assessment9,12.