化妆品中汞检测方案(测汞仪)

( DIRECT AA MERCURY DETERMINATION IN COSMETICS ) INTRODUCTION High mercury concentration can be found in such cosmetic products as skin lightening soaps and creams, makeup cleansing products, and mascara. Mercury in cosmetics exists as inorganic and organic compounds. Inorganic mercury (e.g. ammoniated mercury) is used in skin lightening soaps and creams. Organic mercury compounds, such as thiomersal, are used as cosmetic preservatives in makeup cleansing products and mascara. The European Union Directive (EU Regulation 1223/2009) specifies that mercury compounds are not allowed as ingredients in cosmetics (including soaps, lotions, shampoos and skin bleaching products). However, phenyl mercuric salts for use as a preservative in eye makeup and eye makeup removal products are allowed at concentrations equal to or less than 0.007% by weight. The United States FDA (21 CFR Part 700 Subpart B: Requirements for Specific Cosmetic Products - Section 700.13) allows mercury compounds in eye makeup at concentrations at or below 65 mg/kg expressed as mercury. All other cosmetics must contain mercury at a concentration of less than 1 mg/kg. MEASURING METHOD The measuring method is based on the direct thermal decomposition of a sample using a PYRO-915+ attachment and its consequent determination by flameless AAS with Zeeman background correction using a RA-915M/RA-915+ mercury analyzer. A sample is placed into the sample boat, which is inserted into the first chamber of the atomizer, where the sample is heated at a temperature of 200–800°C depending on the selected operation mode of the PYRO- 915+ attachment. The mercury compounds are evaporated and partially dissociated, forming elemental mercury. All the gaseous products formed are transported into the second chamber of the atomizer by a carrier gas (ambient air). Mercury compounds are totally dissociated and the organic matrix of the sample is burnt out. Downstream from the atomizer the air flow enters the analytical cell heated up to 700°C, and the mercury atoms are detected by the RA-915M analyzer. This approach does not involve preconcentration on a gold trap and “cooling step”, thereby eliminating ensuing problems. The use of ZAAS combined with a “dry” converter provides the highest sensitivity with no interferences from the sample matrix. The ambient air is used as a carrier gas, so that no cylinders with oxygen, argon, or other compressed gases are required. Total time needed for determination of mercury is not longer than 2 minutes. MEASUREMENT RANGE The measurement range of the mass concentration of total mercury is 0.001–300 mg/kg (weight of sample is 10–200 mg, analyzed using heating Mode 3). ANALYSIS FEATURES Rapid direct determination of total mercury without any sample preparation. No sample pre-treatment, no gold traps and/or compressed gases provide very low operating costs. Control of non-selective absorption during the measurement process excludes analysis errors. Low limit of detection, wide dynamic range of measurements. Simple measurement procedure and user-friendly interface enable operation by lab personnel after a short training. Long-term calibration stability; SRMs with any matrix (both liquid and solid) can be used for calibration and validation. EQUIPMENT AND REAGENTS The following equipment and materials are used for analysis: Mercury analyzer RА-915М (RА-915+) with PYRO-915+ attachment; PC with Windows® ХР/Vista/7/8/10 and RAPID software; SRM of mercury; The information in this leaflet is supplemental. To get more specific information on this method, please contact the developer of this method LUMEX INSTRUMENTS Group. NORTH AMERICA Lumex Instruments Canada 0890278 B.C. Ltd. E-mail: info@lumexinstruments.com www.lumexinstruments.com EUROPE Lumex Analytics GmbH E-mail: info@lumexanalytics.de www.lumexanalytics.de RUSSIA Lumex-Marketing LLC E-mail: sales@lumex.ru www.lumexinstruments.com CHINA Beijing Lumex Analytical Equipment Co. Ltd. E-mail: lumex@lumex.com.cn www.lumexcn.com    大部分的化妆品都会含有一定量的汞。我们都知道，汞有美白的效果，但是，如果化妆品里含有过量的汞的话，就有可能危害到我们的肌肤健康。现在市面上经常曝光的一些美白祛斑类产品汞超标甚至高达万倍。高效美白化妆品汞含量值严重超标，而且化妆品的的前处理复杂，高浓度样品会污染检测仪器，导致检测结果不准确。化妆品中的汞以无机和有机化合物的形式存在。无机汞（如氨化汞）用于皮肤亮光肥皂和乳膏。有机汞化合物，如硫柳汞，被用作化妆品清洁剂和睫毛膏中的化妆品防腐剂。   该测量方法是燃烧热解法（符合US EPA 7473）直接测定固态样品中的汞含量，样品在PYRO-915+附件中进行热雾化，然后用RA-915M汞分析仪进行塞曼背景校正，由原子吸收法确定。将水样放入木炭床中，将其放入雾化器的第一个腔室中，其中样品在200℃～800℃的温度下加热。汞化合物被蒸发并部分解离，形成元素汞。形成的所有气态产物通过载气（环境空气）被输送到雾化器的第二室。汞化合物完全解离，样品的有机基质烧坏。在雾化器的下游，气流进入到700℃的分析池，并用RA-915M分析仪检测汞原子。