Assessing the Legacy of Red Mud Pollution in a Shallow Freshwater Lake: Arsenic Accumulation and Speciation in Macrophytes

Abstract

Little is known about long-term ecological responses in lakes following red mud pollution. Among red mud contaminants, arsenic (As) is of considerable concern. Determination of the species of As accumulated in aquatic organisms provides important information about the biogeochemical cycling of the element and transfer through the aquatic food-web to higher organisms. We used coupled ion chromatography and inductively coupled plasma mass spectrometry (ICP-MS) to assess As speciation in tissues of five macrophyte taxa in Kinghorn Loch, U.K., 30 years following the diversion of red mud pollution from the lake. Toxic inorganic As was the dominant species in the studied macrophytes, with As species concentrations varying with macrophyte taxon and tissue type. The highest As content measured in roots of Persicaria amphibia (L.) Gray (87.2 mg kg(-1)) greatly exceeded the 3-10 mg kg(-1) range suggested as a potential phytotoxic level. Accumulation of toxic As species by plants suggested toxicological risk to higher organisms known to utilize macrophytes as a food source.

Soil quality and vegetation performance indicators for sustainable rehabilitation of bauxite residue disposal areas: a review

“…The recommendations that shoot metal concentrations do not exceed domestic animal toxicity limits (Mendez and Maier 2008) have not been investigated in bauxite residue revegetation, and this is an area requiring future attention. This is particularly the case in light of the more recent publications highlighting the As, Hg, and V risks from residues when poorly managed (Mišík et al 2014;Olszewska et al 2016).…”

“…Consequently, almost all bauxite residue is stored in land-based BRDAs (Burke et al 2013), with many facilities reaching several hundred hectares in footprint (Residue Solutions 2007;Cristol and Greenhalgh 2018). Unless properly managed, BRDAs pose a high risk to the environment and surrounding communities (Mayes et al 2011;Ruyters et al 2011;Burke et al 2012;Olszewska et al 2016;Ren et al 2018).…”

“…Drainage systems installed above the liner can recycle drainage back to the refinery as a means of closing the waterbalance and capturing high-strength alumina solutions before release to the environment. Despite these mitigation procedures, uncontrolled discharges from stored residues still occur, highlighting the ever-present risks to aquatic and terrestrial systems (Olszewska et al 2016;Ren et al 2018) and the need for effective management strategies, both during the active lifespan of a BRDA and post-closure.…”

Assessing the legacy of red mud pollution in a shallow freshwater lake: long-term chemical recovery in the water column

“…The likely impact of the elevated pH in Kinghorn Loch in the years immediately following the diversion of the leachate, as well as the potential competition for sorption sites between some red mud constituents, indicate that these interactions may be a dominant factor regulating chemical recovery. However, uptake into biota may also be a major pathway of internal cycling of red mud pollutants; significant accumulation of As species was reported in tissues of macrophytes in Kinghorn Loch, as recently as 2013 (Olszewska et al, 2016).…”

“…We tested this hypothesis using long-term monitoring data documenting chemical recovery in Kinghorn Loch, UK, following red mud pollution control in 1983 (Olszewska et al, 2016).…”