Mercury distribution in an invasive species (Asystasia gangetica) from Peninsular Malaysia

In this study, the Hg levels in eight parts of Asystasia gangetica (L.) T. Anderson collected from 14 sites were determined using a Mercury Atomizer MA-1S and a Mercury Detector MD-1. It was found that the ranges for all the parts were 3.21-18.2 μg/kg dry weight for flowers, 1.29-11.2 μg/kg dry weight forstalks, 0.32- 29.4 μg/kg dry weight for seeds, 0.87-10.2 μg/kg dry weight for pericarps, 1.45-18.1 μg/kg dry weight for remainders, 11.8-68.2 μg/kg dry weight for leaves, 0.73-20.9 μg/kg dry weight for stems, and 3.40-33.1 μg/kg dry weight for roots. The overall Hg accumulation pattern in decreasing concentrations was leaf > root > flower > flower remains > stalk > stem > pericarp > seed. This study provided the background levels of Hg in this non-native invasive weed species in Malaysia. However, further studies are needed to confirm it as a biomonitors of Hg in this region