J. Cosmet. Sci., 69, 279–291 ( July/August 2018) 279 Determination of Fluorescent Whitening Agents in Cosmetics and Liquid Detergent by High-Performance Liquid Chromatography with Diode Array Detector in Tandem with Fluorescence Detector YU-XIANG GU, JIN-QIN YANG, SI-YI PAN, LEI WANG, and ZE-LIN ZHOU, Shanghai Institute of Quality Inspection and Technical Research, Shanghai 200233, People’s Republic of China (Y.-X.G., J.-Q.Y., S.-Y.P., L.W., Z.-L.Z.) Accepted for publication August 3, 2018. Synopsis Five distyryl-type fl uorescent whitening agents (FWA85, 210, 220, 351, and 353) were determined in cosmetics and liquid detergent by high-performance liquid chromatography with diode array detector in tandem with fl uorescence detector. The samples were extracted with ultrasound in 33% acetonitrile for 10 minutes and the components were determined by ion-pair chromatography on an MG C18 column. The limits of detection were from 0.01 to 0.1 mg·kg-1 and the limits of quantifi cation were from 0.04 to 0.4 mg·kg-1. The recovery was from 80.7 to 103.3%. A linear relationship was present from 0.10 to 100 μg·ml-1 of FWAs. The protocol was simple, sensitive, selective, and was successfully applied to analyze distyryl-type FWAs in cosmetics and liquid detergent. FWA351 and FWA85 were detected in several samples with the concentrations of 19.4–1,130 mg·kg-1. INTRODUCTION Fluorescent whitening agents (FWAs) belong to the colorless or weakly colored organic compounds in solutions or on substrates, which could enhance the optical impression of whiteness and brightness through absorbing light in the UV range (290–400 nm) and emitting visible blue light (400–480 nm). They are numerous in variety with different structural properties. The main types of FWAs include distyryl-type, benzoxazole-type, pyrazoline-type, and coumarin-type the distyryl-type is the most widely used product. Now FWAs extensively apply in textiles, paper manufacturing, household detergents, plastic products, and cosmetics to eliminate the yellowish cast of white fabrics and increase the whiteness and brightness of products (1–4). Usage of FWAs in detergent could be traced back to the 1940s. In recent years, with the rising demand for the appearance of the products from consumers, application of FWAs Address all correspondence to Yu-Xiang Gu at guyuxiang@aliyun.com.

JOURNAL OF COSMETIC SCIENCE 280 in detergent becomes more and more extensive. Its function cannot be replaced by any other additives. FWAs has been listed in the industry standard of detergent raw materials in some countries (5), and almost 40% of the world’s FWAs production is used in the deter- gent industry (6). Because there is no requirement to label FWAs in detergent labels according to the regulation, very few manufacturers state that their products contain FWAs. Compared with detergents, the application of FWAs in cosmetics is less, but it has been applied in some brands of products, e.g., Clinique (Estee Lauder, New York, NY), Estee Lauder (Estee Lauder, New York, NY), Essence Studio Nails (Irvine, CA). FWA351 and FWA184 are included in International Nomenclature Cosmetic Ingredients. FWAs may make the appearance of cosmetics more white and crystal clear. As a fashion product, pleasant color is an important factor to attract consumers to buy. The possible toxicity of FWAs is not currently settled, with some studies suggesting that FWAs pose no risk to human, whereas other fi ndings indicate potential for allergic and even carcinogenic effects. According to Shu’s report (4), toxic effects of FWAs have not yet been observed and the toxicological information available on specifi c types of FWAs is rather limited, which indicates that contact with FWAs or even FWAs that migrate into food from plastic packaging containers does not represent a risk to human health. However, in other reports, FWAs have been considered to be a public health concern because of their poten- tially allergic and carcinogenic effect to humans, and the abuse of FWAs has aroused special concern recently (7,8). The Environmental Working Group indicated that FWAs could cause skin allergies or pruritus in sunlight, and the light-sensitive consumers should avoid contact with such substances (9). Moreover, FWAs are diffi cult to be degraded in terms of their special chemical stability (10), whose overuse could contribute to environmental pol- lution and further threaten human health as a result of their accumulation in the body. Because information on the contents of FWAs in most cosmetics and detergent is unclear and unavailable, toxicologists cannot evaluate the possible health effects of FWAs in these products. The increasing public health concern regarding the usage of FWAs in various consumer products has stimulated our interest to investigate the content and distribution of FWAs in cosmetics and detergent, especially the most widely used distyryl-type FWAs. In the past, determination of FWAs was performed by whiteness method (11), thin-layer chromatography (12), and direct spectrophotometric method (13). These approaches lack specifi city to individual FWAs and are affected by various interfering compounds. Later, quan- titation of FWAs by high-performance liquid chromatography (HPLC) has been applied to food and environmental samples (8,14–17). Recent years, combining HPLC and tandem mass spectrometry (tandem MS) with ionspray or electrospray ionization has been reported as a powerful method for determining FWAs in some materials (10,18,19). The current applica- tions of these methods include paper, water, textile, food, etc. However, to our knowledge, analytical methods have been rarely reported for the determination of FWAs in cosmetics and detergent. Because quantitation of individual FWA concentration is critical in investigating the risk assessment of FWAs because of their different toxic effects, it was necessary to establish a specialized method for the FWAs in cosmetics and liquid detergent because of the varying sample composition and ensure quality control during manufacture and market supervision. In the present study, a rapid and simple HPLC protocol is reported for the determination of fi ve distyryl-type FWAs (FWA85, FWA210, FWA220, FWA351, and FWA353 name and structure are shown in Figure 1) in cosmetics and detergent. Diode array detector (DAD) in tandem with fl uorescence detector (FLD) is employed to improve the confi rmatory ability