Advanced Drinking Groundwater As Phytofiltration by the Hyperaccumulating Fern Pteris vittata

Abstract

The reuse of Pteris vittata plants for multiple phytofiltration cycles is a main issue to allow an efficient phytoremediation of arsenic (As)-contaminated groundwater. Here, we assessed the capacity of phytofiltration of P. vittata plants grown for two cycles on naturally As-contaminated drinking water (collected in Central Italy), spaced by a growth cycle on non-contaminated water (N cycle). P. vittata young plants, with extensive frond and root development, were suspended individually in 15 L of water with initial As of 59 µg/L, without any additional treatment or water refilling. During cycle 1, in 45 days P. vittata plants reduced As concentration below 10 µg/L, the allowed EU limits for drinking water. During the subsequent 30 day-N cycle on non-contaminated water, no leaching of As from the roots was observed, while the water pH increased 0.9 Units, but is within the allowed limits. During cycle 2, under the same conditions as cycle 1, As concentration decreased below 10 µg/L in less than seven days. These results show that P. vittata young plants, previously used for the phytofiltration of As, do not extrude As and, when reused, remove As much more rapidly. No additional treatments were required during phytofiltration and thus this represents a sustainable, efficient, and scalable strategy.

Removal of Methylene Blue from Wastewater by Waste Roots from the Arsenic-Hyperaccumulator Pteris vittata: Fixed Bed Adsorption Kinetics

“…Thus, the ferns were moved to net pots filled with expanded clay and placed in 15L tanks of tap water for hydroponic culture. Each tank hosted 12 ferns, and after 4–5 months, the roots occupied most of the space in the tank; thus, the roots were cut and harvested [ 18 ]. The waste roots were pretreated before the adsorption tests, following the procedure reported in the work of Mazzeo et al [ 25 ].…”

“…Several studies have documented the ability of PV to remove large amounts of arsenic (As) (up to 23.000 mg/kg) from soil [ 15 ] and directly from the water in hydroponic culture systems [ 16 , 17 ]. Multiple phytoremediation cycles were also successfully conducted [ 18 ] showing that PV does not release any of the previously accumulated As.…”

A Green Approach Based on Micro-X-ray Fluorescence for Arsenic, Micro- and Macronutrients Detection in Pteris vittata

“…The propagation and growth of ferns were performed in the greenhouse under controlled conditions as previously described [19,25]. Six-month-old ferns with 7-8 fronds and about 30 cm tall were transferred in pots containing soils naturally rich in As, with two different As concentrations: Soil 1 (S1) and Soil 2 (S2), with average As concentrations of 58 mg/kg and 750 mg/kg, respectively (Figure 1).…”

On-site spectroscopy as a tool for monitoring phytoremediation by ferns of arsenic contaminated water

“…Measurement of As in the biomass of plants evaluating their bioaccumulation requires expensive, invasive and timeconsuming laboratory chemical methods [9]. We have previously shown that young plants of Pteris vittata when transferred to naturally As-contaminated groundwater are able to remove up to 98% of As in 60 days [10]. Here a comparative evaluation was performed on Pteris vittata leaves collected from plants grown on As contaminated and not contaminated water adopting reflectance spectroscopy.…”