Arsenic and other heavy metal accumulation in plants and algae growing naturally in contaminated area of West Bengal, India.

Abstract The present study was conducted to quantify the arsenic (As) and other heavy metal concentrations in the plants and algae growing naturally in As contaminated blocks of North-24-Pargana and Nandia district, West Bengal, India to assess their bioaccumulation potential. The plant species included five macrophytes and five algae were collected from the nine selected sites for estimation of As and other heavy metals accumulated therein by using Inductively Coupled Plasma Mass Spectrophotometer (ICP-MS). Results revealed that maximum As concentration (117 mg kg −1 ) was recorded in the agricultural soil at the Barasat followed by Beliaghat (111 mg kg −1 ) sites of North-24-Pargana. Similarly, concentration of selenium (Si, 249 mg kg −1 ), lead (Pb, 79.4 mg kg −1 ), chromium (Cr, 138 mg kg −1 ) was also found maximum in the soil at Barasat and cadmium (Cd, 163 mg kg −1 ) nickel (Ni, 36.5 mg kg −1 ) at Vijaynagar site. Among the macrophytes, Eichhornia crassipes found more dominating species in As contaminated area and accumulate As (597 mg kg −1 ) in the shoot at kanchrapara site. The Lemna minor found to accumulate maximum As (735 mg kg −1 ) in the leaves at Sonadanga and Pistia stratiotes accumulated minimum As (24.5 mg kg −1 ) in the fronds from Ranaghat site. In case of diatoms, maximum As (760 mg kg −1 ) was accumulated at Kanchrapara site followed by Hydrodictiyon reticulatum (403 mg kg −1 ) at the Ranaghat site. High concentration of As and other heavy metal in soil indicates long term effects of irrigation with contaminated ground water, however, high concentration of heavy metals in naturally growing plants and algae revealed their mobilization through leaching and possible food chain contamination. Therefore, efficient heavy metal accumulator macrophytes Eichhornia crassipes, Lemna minor, Spirodela polyrhiza may be exploited in removing metals from contaminated water by developing a plant based treatment system. However, As accumulator algal species may be used as a bioresource for understanding algae mediated As detoxification and bioindication studies.