Developed Moss Heavy Metal Detection

Because of special physical structure and a strong adsorption, moss can be used as an indicator plant for environmental pollution. By detecting pollutants contented inside of moss, we can monitor the air quality of the environment and design test progress. It can not only contribute to survey and monitor heavy metal pollution in the air, but also help the reseachers to develop the corresponding methods in heavy metals detection. In addition, the results can provide scientific support for the government decision-making and management control.The article collects and consults a certain amount of domestic and foreign literature about heavy metal detection technology in moss. By considering the actual environmental situation of China, the article designs a series of methods, including moss heavy metal detection and analysis. First, this article selects the quality control standards and moss species, and then prepares samples and discusses digestion and detection method, et al. The initial framework of heavy metals in moss monitoring is established.First, the quality control standards and moss samples select. Quality control standards should select the similar material and substance quality. Finally, we select tea, seaweed, spirulina and citrus leaves. To enable a representative sample moss, we choose different kinds of moss samples from different areas and regions, collecting Haplocladium microphyllum and Mnium from Shanghai, Myuroclada maximowiczii and Hypnum plumaeforme from Zhejiang, Entodon cladorrhizans from Jiangxi.Second, the sample pretreat.The root of moss and mud wipe off; then, distilled water rinse; finally, the moss constant weight in the 70℃ drying oven and crush to preserve in clean seal.Third, the sample digestion methods select. Sample digestion method is commonly used all hydrochloric acid digestion, aqua regia digestion, nitric acid-perchloric acid digestion and the nitric acid digestion. First, by comparing with the sample recovery, we chose the whole nitric acid digestion; then, the nitric acid digestion conditions were optimized. Determing the amount of H2O2 is 2 mL, nitric acid is 4 mL and the sample is 0.040 g. Again, by analysising of advantages and disadvantages contrast the microwave digestion and graphite furnace. Finally, we select the graphite furnace digestion. Digestion temperature is 115℃ and digestion time is 5 h.Fourth, the sample testing methods discuss. Inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma atomic emission spectrometry (ICP-OES) determinate the elements of bryophytes, inclouding Ag、Co、Cu、Mn、Ni、 Pb、Zn、As、Cd、Cr、Sb、Tl、V. Because two instruments have different detection limits, so the ICP-MS is recommended. For Hg element, this article uses cold atomic absorption spectrophotometry. Finding the detectable effect is more ideal.Fifth, using the standard addition recovery, accuracy and related indicators evaluate the heavy metal in moss detection methods. According to the actual situation detect and analyze the heavy metal content in moss samples.In summary, this paper successfully makes the detection methods of heavy metals in the moss.