Perbandingan Metode Destruksi Pada Penetapan Kandungan Timbal (Pb) Dalam Tanaman Kangkung (Ipomoea reptans Poir).

Abstract

Lead contamination in the air and water is usually caused by industrial and domestic wastes as well as motor vehicles’ gas that contain lead. Heavy metal contamination such as lead (Pb) that does go into the environment can be retained by plants. Kangkung (Ipomoea sp) is a kind of favorable vegetables and used to grow near the rivers or ponds in the cities, and is watered with the water from the nearby river or pond. It is therefore necessary to analysed the Pb content in kangkung to know how bad is the Pb contamination goes in the plant. With this regards, it is also necessary to study the best method to analysed the Pb content in kangkung.
 Six-week old land kangkung (Ipomoea reptans Poir), cultivated in hydrophonic media was used as the sample. Four methods were used: dry and wet destruction with standard addition (Pb solution 10 ppm). Method I: dry method with standard solution added before the process, and method II: standard solution was added after the process. Methods III and IV: wet method with standard solution added before and after the process respectively. Dry process was carried out at 500oC and the wet process was at 100 – 120oC. The Pb content was measured by means of Inductively Coupled Plasma Spectrometer (ICPS).
 Percent recoveries of method I, II, III, and IV were 62.60%, 98.60%, 93,08%, and 98.54% respectively. The coefficient of variant (CV) were respectively 3.53%, 2.08%, 1.68%, and 0.78% for method I, II, III and IV.
 So, it can be concluded that method IV was best to analyse the Pb content in kangkung when the concentration of Pb is very small.