Study On The Determination Of Preservatives And Harmful Heavy Metals In Foods And Cosmetics

People couldn’t exist without foods, it contained affluent proteins carbohydrates and fats, but under the effect of physics, biochemistry and microbe could lose it’s color, smell, taste, shape and corrupt to deteriorate. Add preservatives in the food could effectively inhibit bacterium or kill bacterium, accordingly to extend foods protection quality time, but excessive preservatives could damage people’s body. Meanwhile, harmful heavy metals also jeopardize human’s health, many foods in it’s process of growth or fabrication bring harmful heavy metals, heavy metals could intensively interact with protein and enzyme in the body cause them to lose activity, and it also probably accumulate in organ of human’s body to result in chronic intoxication.Besides foods, people also couldn’t live without cosmetics in daily life. Cosmetics could distinguish two great kinds which were cleaning cosmetic and cosmetology cosmetic, used cosmetics may clean muscle and skin, beauty appearance, delay senility. But cosmetics could also corrupt to deteriorate, bringing preservatives may effectively prolong cosmetics useful life. Meanwhile, in the process of cosmetics could possibly bring harmful heavy metals, if people use those exceeding standard preservatives and harmful heavy metals in cosmetics can damage people’s skin and physical.Therefore, it is necessary to study on the determination of preservatives and harmful heavy metals in foods and cosmetics. It can guide people choose daily life products and coup those businessman who weren’t abide by law. This thesis focused on those researches:1. Selecting cinnamic acid as an internal standard, a high performance liquid chromatography ( HPLC ) was developed for the determination of preservatives in foods and cosmetics, with acetonitrile, water, tetrahydrofuran as the mobile phase adapted gradient elution. The detection wavelength was 254 nm, The flow rate was 1.0 ml/min. Samples were extracted by ethanol-water. Assay method’s linear correlation, precision and recovery was all correspond to request.2. To establish atomic absorption spectrometry (AAS) determined five harmful heavy metals in foods and cosmetics. Hydride-generation - AAS determined As, Hg, Pb; flame - AAS determined Cd, Cr. Linear correlation, precision and recovery of five heavy metal were all correspond to detection request.3. To inspected preservatives in food and cosmetic’s extraction rate by supersound extraction time and matching of extraction solvent. Result: it can get high extraction rate by supersound 30 minutes and dehydrated alcohol: water ( 80 :20).4. It also inspected heavy metal pre-processing in food and cosmetic. Result: As, Pb, Cd, Cr adopted nitric acid - perchloric acid could get nice treatment efficiency, and Hg adopted dioxogen-perchloric disposal to be well.