Foliar uptake experiment was conducted in this project of “The Application of Raman Microspectrometry in Environmental Forensics”. The experiment was conducted in Phytotron of National Taiwan University between May 29th and September 17th, 2015. The experiment considered different concentrations of Pb in soil (background value and 1,000 mg/kg) and with or without spraying lead nitrate solution on leaves (500 mg Pb/L). There were a total of 16 experimental pots, including 1control group and 3 experimental groups (root group, leaf group, and root-leaf combination group), each with 4 pots (for 4 crop growing stages). Total Pb concentration was analyzed for soil, root, shoot, leaf, and rice, with a total of 64 samples. Further, the project completed 39 soil analysis and 3 plant tissue analysis of Raman Microspectrometry. To sum up, there were 106 sample analysis in total. In addition, 10 literature reviews were also completed. The root sample from the root-leaf combination group was analyzed by Raman Microspectrometry fitted with a 785 nm excitation source, 10X magnification, and laser power of 15 mW. A total of 4 peaks were detected at 247 cm-1、376 cm-1、1268 cm-1及1575 cm-1. It is noted that 247 cm-1 and 376 cm-1 may be resulted from Pb-S bonding (P. N. Williams et al., 2014). Pb(NO3)2, PbSO4, PbO, cerussite, and Pb-containing sand were also analyzed by Raman Microspectrometry fitted with a 532 nm excitation source, 10X magnification, and various laser power. Contaminated soil was analyzed by Raman Microspectrometry fitted with a 785 nm excitation source, 10X magnification, and laser power of 24.9 mW.

Raman microspectrometry, soil, rice