Rufus Lee Chaney

• Ph.D.
• Environmental Agronomist at Chaney Environmental

Metals and metalloids (hereafter, metal(loid)s) in plant‐based foods are a source of exposure to humans, but not all metal(loid)‐food interactions are the same. Differences exist between metal(loid)s in terms of their behavior in soils and in how they are taken up by plants and stored in the edible plant tissue/food. Thus, there cannot be one consi...

Background and aims Nickel (Ni) deficiency has been reported to occur in soybean (Glycine max) grown on leached tropical soils in Brazil. We aimed to determine whether an internal or external Ni supply can compensate for low Ni within the seed by assessing whether the amount of Ni in the seed whether the foliar-application of aqueous NiSO4 influenc...

Background When studying metallophytes and hyperaccumulator plants, it is often desired to assess the level of tolerance of a specific trace metal/metalloid in a putative tolerant species, to determine root and shoot accumulation of the trace metal/metalloid of interest, or to establish whether a trace metal/metalloid has an essential function. The...

Excessive Cd accumulation in rice grain has caused chronic Cd diseases in humans. In most crops, 100 times more Zn than Cd strongly inhibits Cd uptake and translocation. However, this response is not found for rice (Oryza sativa L.), which was found to have an unusual Cd uptake pattern compared with other crops, such as spinach (Spinacia oleracea L...

Ni contaminated soils may be Ni phytotoxic depending on soil and plant properties. Little research on environmental Ni was specifically focused on persistent remediation of Ni phytotoxic soils. Successful revegetation at Sudbury provided an example of what could be achieved. But more knowledge was needed to determine the range of remediation techno...

Health risks caused by food containing Cd is a concern worldwide. Interaction between Mn and Cd has been widely studied in normal hydroponic solution with high ion activities (e.g., the study on sharing of transporter Natural Resistance–Associated Macrophage Protein 5 between Mn and Cd in rice [Oryza sativa L.]). However, interaction of Mn and Cd i...

Arsenic exposure through rice consumption is a growing concern. Compared to Continuous Flooding (CF), irrigation practices that dry the soil at least once during the growing season [referred to here as Alternate Wetting and Drying (AWD)] can decrease As accumulation in grain; however, this can simultaneously increase grain Cd to potentially unsafe...

Background and aimsPhosphorus is one of the major nutrients that directly or indirectly affects all aspects of plant growth. Tropical nickel hyperaccumulators, including Phyllanthus rufuschaneyi and Rinorea cf. bengalensis from Borneo Island (in the Malaysian state of Sabah), have evolved to grow in extremely P-impoverished ultramafic soils. This s...

Background and Aims In tropical ultramafic soils, potassium (K) is typically the most growth limiting nutrient. However, tropical nickel (Ni) hyperaccumulator plants, including Phyllanthus rufuschaneyi and Rinorea cf. bengalensis (which are ‘metal crops’ used in agromining) from Malaysia, have unusually high K shoot accumulation compared to other s...

The concept of phytomining is a natural extension of botanical prospecting and the study of metal biochemistry and biogeography of metal hyperaccumulator plants. Some elements may be phytoextracted to remediate soils, but the recovered biomass would have little economic value (e.g. Cd, As, etc.) and disposal of the biomass would be a cost. A few el...

Agromining involves growing selected hyperaccumulator plant species (‘metal crops’) on low-grade ore bodies or mineralized (e.g. ultramafic) soils, or anthropogenic metal-rich materials (e.g. contaminated soils, mine spoils, industrial sludge), followed by harvesting and incineration of the biomass to produce a ‘bio-ore’ from which target metals or...

Substantial unrealized opportunities exist for economic Ni agromining in the tropics. However , until recently this technology has remained relatively unexploited in this part of the world. In this chapter, we discuss the progress of tropical Ni agromining in two regions, namely Southeast Asia and the neotropical region. Significant advances have b...

Comprehensive information on the elemental profile of tobacco used in counterfeit cigarettes is limited. This study investigated the concentration of toxic elements in counterfeit cigarettes seized in the US and compared the results with their genuine equivalents. Concentration of various elements, including As, Ca, Cd, Co, Cu, Fe, K, Mg, Mn, Ni, P...

Aims Knowledge on the ecophysiology of facultative cobalt hyperaccumulators is limited. The nickel hyperaccumulator Rinorea cf. bengalensis from Borneo can accumulate high concentrations of cobalt in nature. This study investigates the cobalt accumulation potential of Rinorea cf. bengalensis in relation to nickel levels in soils and the subsequent...

Background Phytoextraction is an in situ technique that can be applied to minerals and mining wastes using hyperaccumulator plants to purposely bio-concentrate high levels of metals or metalloids into their shoots in order to remove them from the substrate, while achieving monetary gain. Phytoextraction can be applied to a limited number of element...

Aims This study investigated the physico-geochemical properties of three types of ultramafic substrates in Sabah (Malaysia) and further characterised their influence on nickel (Ni) accumulation in two selected tropical ‘metal crops’ (Phyllanthus rufuschaneyi and Rinorea cf. bengalensis). Methods Three experiments, consisting of a randomised block...

Agromining is an emerging technology that utilizes selected 'metal crops' (= hyperaccumulator plants) to extract valuable target metals from unconventional resources for profit from mineral-ised soils. Growth characteristics, shoot metal concentrations, and agrominable locations are important considerations in economic agromining. Globally, the gre...

Ultramafic soils are usually marginal in macronutrients (nitrogen (N), phosphorus (P), potassium (K) and calcium (Ca)) for growth of crop plants. Commercial nickel (Ni) agromining is dependent on attaining high yield and high Ni concentration in harvestable biomass of Ni hyperaccumulator species. We previously reported on the biomass responses of t...

Previous research has shown that ground rubber from tyres can be used to supply fertiliser zinc (Zn) for prevention of Zn-deficiency in crops, and that inoculation of the ground rubber with several bacterial species hastens the release of Zn to the soil. We evaluated the ability of several microbial combinations to speed the release of Zn from grou...

Agromining is the chain of processes of phytoextraction of economically valuable elements by selected hyperaccumulator plants, and subsequent processing of biomass to produce targeted metals or commercial compounds of high value. Although substantial unrealized opportunities exist for developing economic nickel (Ni) agromining in the tropics, this...

Effects of different soil amendment treatments on the bioavailability of lead (Pb) in soil from a smelter emission contaminated site in Joplin, Missouri, were evaluated in a mouse model. Similar estimates of relative bioavailability for Pb in untreated or treated soil were obtained in mice and in the well-established juvenile swine model. In the mo...

Particle or clay sedimentation calculator for centrifuge speed and time

Serpentine soils and ultramafic laterites develop over ultramafic bedrock and are important geological materials from environmental, geochemical, and industrial standpoints. They have naturally elevated concentrations of trace metals, such as Ni, Cr, and Co, and also high levels of Fe and Mg. Minerals host these trace metals and influence metal mob...

There are concerns regarding the fate of nutrients from surface application of animal manure. One approach to reduce losses of P is to treat manure with industrial byproducts such as flue gas desulfurization (FGD) gypsum. However, concerns regarding potentially toxic elements contributed to the environment have arisen based on previous element‐rich...

With the establishment by CODEX of a 200 ng/g limit of inorganic arsenic (iAs) in polished rice grain, more analyses of iAs will be necessary to ensure compliance in regulatory and trade applications, to assess quality control in commercial rice production, and to conduct research involving iAs in rice crops. Although analytical methods using high-...

Flue gas desulfurization gypsum (FGDG) from coal‐fired power plants is readily available for agricultural use in many US regions. Broiler litter (BL) provides plant available N, P, and K but can be a source of unwanted As, Cu, and Zn. As a source of Ca and S, FGDG can reduce losses of P and other elements in runoff from BL‐amended areas. Rainfall s...

The concept of phytomining is a natural extension of botanical prospecting and the study of metal biochemistry and biogeography of metal hyperaccumulator plants. Some elements may be phyto-extracted to remediate soils, but the recovered biomass would have little economic value (Cd, As, etc.) and disposal of the biomass would be a cost. A few elemen...

Agromining involves growing selected hyperaccumulator plant species (‘metal crops’) on low-grade ore bodies or mineralized (ultramafic) soils, or anthropogenic metal rich materials (e.g. contaminated soils, mine spoils, industrial sludge), prior to biomass harvesting and incineration to recover valuable metals or salts. This chapter begins with an...

The concept of phytomining is a natural extension of botanical prospecting and the study of metal biochemistry and biogeography of metal hyperaccumulator plants. Some elements may be phyto-extracted to remediate soils, but the recovered biomass would have little economic value (Cd, As, etc.) and disposal of the biomass would be a cost. A few elemen...

Agromining involves growing selected hyperaccumulator plant species ('metal crops') on low-grade ore bodies or mineralized (ultramafic) soils, or anthropogenic metal rich materials (e.g. contaminated soils, mine spoils, industrial sludge), prior to biomass harvesting and incineration to recover valuable metals or salts. This chapter begins with an...

Cadmium contamination in soil is a substantial global problem, and of significant concern due to high food-chain transfer. Cadmium hyperaccumulators are of particular interest because of their ability to tolerate and take up significant amounts of heavy metal pollution from soils. One particular plant, Noccaea caerulescens (formerly, Thlaspi caerul...

Cadmium (Cd)-mineralized soils occur in many nations. When these soils are noncalcareous, crops and especially leafy vegetables such as lettuce (Lactuca sativa L.) and spinach (Spinacia oleracea L.) may accumulate levels of Cd in their edible portions that exceed international standards. Vegetable crops grown on Lockwood loam from Monterey County,...

Serpentine soils have elevated concentrations of trace metals including nickel, cobalt, and chromium compared to non-serpentine soils. Identifying the nickel bearing minerals allows for prediction of potential mobility of nickel. Synchrotron-based techniques can identify the solid-phase chemical forms of nickel with minimal sample treatment. Elemen...

Gypsum (calcium sulfate dihydrate, CaSO 4 ⋅2H 2 O) has long been used to improve soils and crop production, and its use has recently been encouraged by the USDA–NRCS for soil conservation through a new Conservation Practice Standard: Code 333. However, there is concern regarding the adverse effects of excessive direct ingestion of sulfate in gypsum...

Metal contaminants in soils can persist for millennia, causing lasting negative impacts on local ecosystems. Long‐term contaminant bioavailability is related to soil pH and to the strength and stability of solid‐phase associations. We combined physical density separation with synchrotron‐based microspectroscopy to reduce solid‐phase complexity and...

Phytoremediation of inorganics is comprised of technologies to protect the environment from contaminated soils. This broad group of technologies includes phytoextraction (removal from soil), phytomining (accumulating economic metal value in plant biomass) and phytostabilization (limiting plant metals and soil metal uptake and/or bioavailability usi...

Rice (Oryza sativa L.) grown on cadmium (Cd) contaminated soils has caused health problems in Asian subsistence rice farmers. For other crops, normal co-contaminant zinc (Zn) inhibits the increased uptake of Cd. We used a multi-chelator buffered nutrient solution to characterize the interaction of Zn and Cd in uptake-translocation of Cd in ‘Lemont’...

Background Nickel (Ni) phytomining operations cultivate hyperaccumulator plants (‘metal crops’) on Ni-rich (ultramafic) soils, followed by harvesting and incineration of the biomass to produce a high-grade ‘bio-ore’ from which Ni metal or pure Ni salts are recovered. Scope This review examines the current status, progress and challenges in the deve...

This study assessed potential bioaccumulation of various trace elements in grasses and earthworms as a consequence of soil incorporation of organic amendments for in situ remediation of an orchard field soil contaminated with organochlorine and Pb pesticide residues. In this experiment, four organic amendments of differing total organic carbon cont...

Rice (Oryza sativa L.) cultivation is critically important for global food security, yet it also represents a significant fraction of agricultural greenhouse gas (GHG) emissions and water resource use. Alternate wetting and drying (AWD) of rice fields has been shown to reduce both methane (CH4) emissions and water use, but its effect on grain yield...

The genus Alyssum (Brassicaceae) contains Ni hyperaccumulators (50), many of which can achieve 30 g kg⁻¹ Ni in dry leaf. Some Alyssum hyperaccumulators are viable candidates for commercial Ni phytoremediation and phytomining technologies. It is not known whether these species secrete organic and/or amino acids into the rhizosphere to solubilize Ni,...

Performance of compost and biochar amendments for in situ risk mitigation of aged DDT, DDE and dieldrin residues in an old orchard soil was examined. The change in bioavailability of pesticide residues to Lumbricus terrestris L. relative to the unamended control soil was assessed using 4-L soil microcosms with and without plant cover in a 48-day ex...

Hazards of soil-borne Pb to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, we measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contaminated soils. Relative bioavailabilities were expressed by comparison wi...

There are concerns of potential food chain transfer of metals in crops grown on lead-arsenate-contaminated soils. The objective of this study was to investigate lead and arsenic uptake by four potato (Solanum tuberosum L.) cultivars grown on lead-arsenate-contaminated soils with lead and arsenic concentrations ranging from 350 to 961 and 43 to 290...

The aim of this two-year field experiment was to investigate agronomic and economic efficiency of ground tire rubber and rubber ash as zinc (Zn) sources for wheat (Triticum aestivum L. cvs. Kavir and Back Cross) compared with a commercial Zn-sulfate. A similar rate of Zn was used by soil application of 40 kg/ha Zn-sulfate, 200 kg/ha waste tire rubb...

Agromining uses hyperaccumulator plants to extract nickel metal from low-grade soil resources or minerals waste. The sap of this tree (Phyllanthus balgooyi) from Malaysia is bright green from nickel ions (20%), this makes it possible to “tap” into plants to obtain nickel from contaminated sites. DOI: 10.1021/es506031u

Rice (Oryza sativa L.) grown on Zn mine waste contaminated soils has caused unequivocal Cd effects on kidney and occasional bone disease (itai-itai) in subsistence rice farmers, but high intake of Cd from other foods has not caused similar effects. Research has clarified two important topics about how Cd from mine waste contaminated rice soils has...

Phytomining technology employs hyperaccumulator plants to take up metal in harvestable plant biomass. Harvesting, drying and incineration of the biomass generates a high-grade bio-ore. We propose that “agromining” (a variant of phytomining) could provide local communities with an alternative type of agriculture on degraded lands; farming not for fo...

A series of field trials were conducted to investigate the potential of Noccaea caerulescens F.K. Mey [syn. Thlaspi caerulescens J &C Presl. (see Koch and Al-Shehbaz 2004)] populations (genotypes) derived from southern France to phytoextract localized Cd/Zn contamination in Thailand. Soil treatments included pH variation and fertilization level and...

Past applications of biosolids to soils at some locations added higher Cd levels than presently permitted. Cadmium phytoextraction would alleviate current land use constraints. Unamended farm soil, and biosolids amended farm and mine soils were obtained from a Fulton Co., IL biosolids management facility. Soils contained 0.16, 22.8, 45.3 mg Cd kg(-...

Concerns have been raised of possible human food chain transfer of lead and arsenic from crops grown on orchard soils with histories of lead arsenate use. The objective of this study was to determine arsenic and lead uptake by three cultivars of carrots grown on four orchard soils with histories of lead arsenate use. Total concentrations of arsenic...

One type of harsh environment for plants is metal- and metalloid-contaminated or mineralized soils: these exists in most countries due to geological formation or to a history of mining and/or smelting. Depending on soil pH and fertility, metal-rich soils may be barren and eroding into wider areas. Some elements present risk to humans, wildlife, liv...

Agriculture is faced with the challenge of providing healthy food for a growing population at minimal environmental cost. Rice (Oryza sativa), the staple crop for the largest number of people on earth, is grown under flooded soil conditions and uses more water and has higher greenhouse gas (GHG) emissions than most crops. The objective of this stud...

Claims have been made recently that glyphosate-resistant (GR) crops sometimes have mineral deficiencies and increased plant disease. This review evaluates the literature that is germane to these claims. Our conclusions are: (1) although there is conflicting literature on the effects of glyphosate on mineral nutrition on GR crops, most of the litera...

Aims An improved understanding of the Ni root-to-shoot translocation mechanism in hyperaccumulators is necessary to increase Ni uptake efficiency for phytoextraction technologies. It has been presumed that an important aspect of Ni translocation and storage involves chelation with organic ligands. It has been reported that exposing several Ni hyper...

Disposal of rubber tires is an environmental challenge in many countries. Recently we introduced a new technology to use rubber as a source of zinc (Zn) for crops. According to the previous results, rubber particles size is a key factor determining the rate of nutrient release from the rubber wastes. In this study, nano-particles were prepared from...

scrofa) as well as weanling rats (Rattus spp.) as human surrogates, have shown that the mineral form of Pb, fed The potential for biosolids products to reduce Pb availability in both in a soil matrix and as pure minerals, can alter in vitro studies) by 37 and 43%, respectively. Three of the four compost soils is the most commonly used remedial opti...

Recent studies have shown that application of phytohormones to shoots of Alyssum murale increased biomass production but did not increase Ni shoot concentration. Increased biomass and Ni phytoextraction efficiency is useful to achieve economically viable phytomining. The objective of this study was to evaluate the effect of two types of phytohormon...

Metals can be stabilized by soil amendments that increase metals adsorption or alter their chemical forms. Such treatments may limit the risk related to the contamination through reduction of metal transfer to the food chain (reduction of metal uptake by plants and its availability to soil organisms) and metals migration within the environment. The...

Fertilizers and other soil amendments are required to maintain soil fertility, but some may be naturally rich in trace elements, or contaminated. As part of the overall consideration of using fertilizers and soil amendments, one should consider the levels of trace elements present in relation to soil, plant, and food-chain processes (precipitation,...

Background and Aims We tested the utility of some biological treatments to hasten degradation of waste tire rubber in soil and thus the release of zinc and sulfur for plant uptake. Methods Three rates of ground tire rubber (0, 150, and 300 mg kg−1) were incorporated into a Zn-deficient calcareous soil. Before addition to the soil, ground rubber wa...

Aims Past studies have demonstrated that hyperaccumulators absorb Ni from the same labile pools in soil as normal plant species. This study investigated whether the Ni hyperaccumulator plant Alyssum corsicum possesses distinct extraction mechanisms for different Ni species present in soils. Different Ni species have different solubilities and poten...

Claims have been made recently that glyphosate-resistant (GR) crops sometimes have mineral deficiencies and increased plant disease. This review evaluates the literature that is germane to these claims. Our conclusions are: (1) although there is conflicting literature on the effects of glyphosate on mineral nutrition on GR crops, most of the litera...

‘Cerasiforne’ tomato (Lycopersicon esculentum Mill.) was grown in soilless potting media contained different substrate formulas including 25:25:50 volume ratio of acid-washed (AWR) or non-washed shredded rubber (NAWR):vermiculite or zeolite:perlite. Additionally, plants were grown in a peat:perlite substrate. Plants grown in media containing AWR ha...

Zinc is an important nutrient for plants, but it can be toxic at high concentrations. The solubility and speciation of Zn is controlled by many factors, especially soil pH and Eh, which can vary in lowland rice culture. This study determined Zn speciation and release kinetics in Cd-Zn cocontaminated alkaline and acidified paddy soils, under various...

Background and aims Silicon (Si) was suggested to enhance plant resistance to toxic elements, and its beneficial role was mainly based on external and internal plant mechanisms. This work aimed at investigating the internal effect of Si on zinc (Zn) detoxification to rice (Oryza sativa L., cv. Tian You 116) seedlings. Methods In a hydroponic experi...

Application of exogenous plant growth regulators was examined as a viable technique to increase the efficiency of plant metal extraction from contaminated soils. The aim of this study was to investigate the alteration of Ni phytoextraction by Alyssum murale, a Ni hyperaccumulator, following the application of cytokinins. The following parameters we...

This study determined Cd speciation and release kinetics in a Cd-Zn cocontaminated alkaline paddy soil, under various flooding periods and draining conditions, by employing synchrotron-based techniques, and a stirred-flow kinetic method. Results revealed that varying flooding periods and draining conditions affected Cd speciation and its release ki...

Ground rubber contains 15–20g Zn kg−1 but very low levels of Cd and could serve as an inexpensive byproduct Zn fertilizer. The aim of this investigation was to test Zn release in a soil treated with ground tire rubber and rubber ash compared with commercial Zn fertilizer and a laboratory grade zinc sulfate. A Zn-deficient soil was chosen from wheat...

The mechanisms of stabilization by silicon-rich amendments of cadmium, zinc, copper and lead in a multi-metal contaminated acidic soil and the mitigation of metal accumulation in rice were investigated in this study. The results from a pot experiment indicated that the application of fly ash (20 and 40gkg(-1)) and steel slag (3 and 6gkg(-1)) increa...

Hyperaccumulator species of the genera Alyssum can accumulate 100 times more Ni than normal crops and are therefore used for phytomining and phytoextraction of nickel contaminated soils. Basic studies on the physiology and metal uptake mechanisms of these plants are needed to increase efficiency and uptake capacity of Nickel (Ni) by hyperaccumulato...