Dysprosium

Dysprosium is a chemical element with the atomic symbol Dy and atomic number 66, belonging to the lanthanide series of rare-earth metals.^[1] It appears as a soft, silvery-white metal at room temperature, exhibiting high thermal neutron absorption and strong magnetic susceptibility that distinguish it among elements.^[2] Discovered in 1886 by French chemist Paul-Émile Lecoq de Boisbaudran through fractional crystallization and spectroscopic separation from holmium oxide, its name derives from the Greek dysprositos, meaning "hard to get at," reflecting the challenges in its isolation.^[2] With an atomic mass of 162.50 u, dysprosium occurs naturally in minerals such as xenotime and monazite, though it constitutes a minor fraction of rare-earth deposits, complicating extraction.^[1] Dysprosium's defining properties include a high magnetic moment and resistance to demagnetization at elevated temperatures, enabling its alloying with neodymium in NdFeB permanent magnets for enhanced coercivity in applications like electric motors, wind turbine generators, and data storage devices.^[3] These magnets underpin technologies critical to renewable energy and electrification, where dysprosium doping improves performance under operational stresses.^[4] In nuclear engineering, dysprosium's exceptional neutron capture cross-section—among the highest for thermal neutrons—positions it as a key material for control rods in reactors, regulating fission without significant fission byproduct generation.^[5] Furthermore, dysprosium compounds find use in solid-state lasers and infrared sources, leveraging their luminescent and radiative efficiencies for analytical and medical instrumentation.^[6] Despite its scarcity and reliance on limited global mining sources, primarily in China, dysprosium remains indispensable for advancing high-performance materials in defense, computing, and clean energy sectors.^[7]

Properties

Physical properties

Dysprosium is a silvery-white rare earth metal with atomic number 66.^[1] Its density at room temperature is 8.55 g/cm³.^[8] The element melts at 1412 °C and boils at 2567 °C.^[8] Dysprosium exhibits a hexagonal close-packed crystal structure in its stable form.^[9] At room temperature, it is paramagnetic, possessing a mass magnetic susceptibility of 5.45 × 10⁻⁶ m³/kg.^[10] The metal demonstrates a Brinell hardness of 500 MPa and a Vickers hardness of 540 MPa.^[11] Dysprosium has one of the highest thermal neutron absorption cross-sections among elements, approximately 950 barns for key isotopes, enabling its role in neutron control applications.^[12] Its linear thermal expansion coefficient is 9.9 × 10⁻⁶ K⁻¹.^[13]

Property	Value	Source
Density (20 °C)	8.55 g/cm³	RSC Periodic Table
Melting point	1412 °C	RSC Periodic Table
Boiling point	2567 °C	RSC Periodic Table
Brinell hardness	500 MPa	WebElements
Thermal expansion coeff.	9.9 × 10⁻⁶ K⁻¹	Engineering ToolBox

Chemical properties

Dysprosium exhibits the electron configuration [Xe] 4f¹⁰ 6s², leading to a predominant +3 oxidation state in its compounds, as the 4f electrons are shielded and the 6s electrons are readily lost.^[8] Less common +2 and +4 states occur under specific conditions, but +3 dominates due to the stability of the half-filled f-shell configuration and lanthanide electronic trends.^[14] The Dy³⁺ ion, with an ionic radius of approximately 0.912 Å in six-coordinate geometry, supports high coordination numbers (typically 7–9) in complexes, arising from its large size and ionic bonding preferences typical of early lanthanides despite contraction effects.^[15] The metal displays moderate reactivity, tarnishing slowly in moist air via surface oxidation and igniting when heated to form the sesquioxide Dy₂O₃ via the reaction 4Dy + 3O₂ → 2Dy₂O₃.^[16] Dysprosium reacts slowly with cold water to generate Dy(OH)₃ and hydrogen, accelerating with hot water, while it dissolves rapidly in dilute mineral acids (except HF, where insoluble DyF₃ passivates the surface).^[14] In aqueous media, Dy³⁺ remains stable as the aquo complex [Dy(H₂O)₈]³⁺ or similar, with hydrolysis minimal at neutral pH due to its intermediate lanthanide positioning.^[17] Dysprosium forms trivalent halides such as DyF₃, DyCl₃, DyBr₃, and DyI₃, which are ionic solids with high melting points reflecting lanthanide ionic character, and the pale yellow-green oxide Dy₂O₃, sparingly soluble in water but amphoteric.^[14] Organometallic derivatives like cyclopentadienyl complexes exist but are air-sensitive and less stable than those of lighter lanthanides. The lanthanide contraction progressively reduces ionic radii across the series (from ~1.03 Å for La³⁺ to 0.86 Å for Lu³⁺ in CN6), compressing Dy³⁺ bonds and enhancing ligand field influences in compounds compared to non-f-block analogs.^[18]

Isotopes

Dysprosium consists of seven stable isotopes, ranging from ¹⁵⁶Dy to ¹⁶⁴Dy, with no primordial radioactive isotopes contributing significantly to its natural abundance.^[19] The weighted average atomic mass is 162.500(1) u, reflecting the relative abundances determined via mass spectrometry.^[19] The isotopic abundances are as follows:

Isotope	Relative atomic mass (u)	Natural abundance (atom %)
¹⁵⁶Dy	155.924 278 99(20)	0.055 60(90)
¹⁵⁸Dy	157.924 404 8(20)	0.095 0(20)
¹⁶⁰Dy	159.925 193 5(20)	2.336(8)
¹⁶¹Dy	160.926 934 6(20)	18.90(2)
¹⁶²Dy	161.926 794 2(20)	25.48(2)
¹⁶³Dy	162.928 728 4(20)	24.87(2)
¹⁶⁴Dy	163.929 181 9(20)	28.18(3)

¹⁶⁴Dy is the most abundant, comprising approximately 28.18% of natural dysprosium.^[19] Dysprosium has 29 known radioactive isotopes, with masses ranging from ¹⁴⁰Dy to ¹⁷⁷Dy, characterized through nuclear reactor experiments and decay studies.^[20] The longest-lived is ¹⁵⁴Dy, with a half-life of 3 × 10⁶ years, decaying primarily via alpha emission.^[20] Another notable isotope is ¹⁵⁹Dy, with a half-life of 144.4 days, undergoing beta-minus decay.^[20] Neutron capture on stable isotopes, such as ¹⁶⁴Dy(n,γ)¹⁶⁵Dy, produces short-lived radioactive daughters like ¹⁶⁵Dy (half-life ~2.3 hours), which can serve as precursors for medical isotopes via further reactions.^[21] Dysprosium isotopes exhibit exceptionally high thermal neutron capture cross-sections, for example, ~2320 barns for ¹⁶⁴Dy at 0.0334 eV, as measured in reactor irradiation experiments.^[22] This absorption occurs predominantly through (n,γ) reactions, leading to radiative capture without fission product generation, a property confirmed by nuclear data evaluations up to 20 MeV.^[23] Such characteristics stem from the even-odd nuclear structure of dysprosium, favoring neutron absorption over fission pathways observed in heavier actinides.^[24]

History

Discovery and isolation

Dysprosium oxide was first isolated in 1886 by French chemist Paul Émile Lecoq de Boisbaudran through fractional crystallization of holmium oxide samples derived from yttrium preparations.^[1]^[25] Lecoq de Boisbaudran detected the presence of dysprosium via distinct spectroscopic lines observed in the spectrum of holmium, which deviated from expected patterns and indicated an impurity requiring separation.^[8] He achieved this by dissolving the oxide in acid, followed by repeated precipitation and crystallization steps, requiring over 30 attempts to obtain a sufficient quantity of the new oxide.^[25]^[20] The isolation highlighted the challenges of separating chemically similar rare earth elements, as dysprosium co-occurred with holmium and other lanthanides in mineral sources like yttria.^[1] While the oxide was obtained, the metallic form was not produced until 1906 by Georges Urbain, who reduced dysprosium compounds using electrolysis or other metallothermic methods.^[1] Early samples remained impure due to limitations in separation techniques, with atomic weight determinations and spectral confirmations revealing persistent contaminants from neighboring elements.^[26] Significant advances in purification occurred only after World War II, when ion-exchange chromatography enabled the production of dysprosium in relatively pure form by the 1950s, overcoming the inefficiencies of earlier fractional methods.^[1] This technique, developed for rare earth separations, allowed for precise elution based on differential affinities, yielding oxides and metals of high purity essential for subsequent characterization and applications.^[27]

Etymology and early research

The name dysprosium originates from the Ancient Greek δυσπρόσιτος (dysprositos), meaning "hard to get at" or "difficult to access," a term chosen by French chemist Paul-Émile Lecoq de Boisbaudran to highlight the challenges in isolating the element from complex rare earth mixtures in yttrium and erbium oxides.^[8] Lecoq de Boisbaudran identified dysprosium oxide (dysprosia) in 1886 through spectroscopic analysis of holmium oxide impurities, requiring over 30 fractionation attempts to separate spectral lines distinct from those of terbium and holmium, elements with which it was frequently conflated in early mineral analyses of gadolinite and xenotime.^[6] This confusion stemmed from overlapping atomic spectra and chemical similarities among heavy lanthanides, delaying unambiguous identification until repeated purification efforts confirmed dysprosium's unique emission lines. Following Lecoq de Boisbaudran's announcement, early 20th-century research emphasized verification of dysprosium's elemental status and basic properties via improved separation techniques. In 1906, French chemist Georges Urbain achieved a purer fraction through fractional crystallization of rare earth double salts, enabling more precise characterization of its optical spectrum and paramagnetism.^[6] Initial studies revealed dysprosium's high magnetic susceptibility, with susceptibility measurements adhering to the Curie-Weiss law across paramagnetic phases, though scarcity limited extensive experimentation to spectroscopic and thermodynamic assessments rather than bulk applications.^[28] These investigations underscored dysprosium's potential as a strongly paramagnetic material but highlighted purification barriers that confined research to academic contexts until mid-century ion-exchange methods advanced yields.

Occurrence and Reserves

Abundance and distribution

Dysprosium exhibits an average crustal abundance of 5.2 to 6.2 parts per million (ppm) in the Earth's crust, positioning it as the 42nd most abundant element overall.^[29]^[30] This places it within the heavy rare earth element (HREE) subgroup, where it constitutes a minor but significant portion relative to lighter rare earths, with total rare earth crustal contents varying from cerium at approximately 60 ppm to heavier elements like lutetium at 0.5 ppm.^[31] In seawater, dysprosium concentrations are trace, typically around 0.9 to 1 nanogram per liter (ng/L), reflecting its low solubility and geochemical partitioning.^[29]^[32] Geochemically, dysprosium is predominantly associated with phosphate minerals such as monazite ((Ce,La,Nd,Th)PO₄) and xenotime (YPO₄), the latter being particularly enriched in HREEs due to ionic radius similarities with yttrium and heavy lanthanides.^[33] It occurs in lesser amounts in fluorocarbonates like bastnäsite ((Ce,La)CO₃F), which favor light rare earth elements but contain trace HREEs.^[34] Dysprosium shows notable enrichment in ion-adsorption clays formed via weathering of granitic rocks, where supergene processes mobilize HREEs from primary minerals and adsorb them onto clay surfaces such as kaolinite, preferentially retaining heavier elements due to stronger electrostatic interactions.^[35] Cosmically, dysprosium's abundance is estimated at approximately 0.28 ppm in carbonaceous meteorites and lower in solar abundances (around 0.002 relative to silicon), primarily synthesized through rapid neutron capture (r-process) in core-collapse supernovae and neutron star mergers, with contributions from slow neutron capture (s-process) in asymptotic giant branch stars.^[32] These nucleosynthesis pathways explain its relatively uniform distribution in primitive solar system materials, contrasting with differentiation-driven crustal enrichments on Earth.^[36]

Major deposits

Global reserves of dysprosium are estimated at approximately 1.1 million metric tons of contained metal, with China holding roughly 50% based on assessments of rare earth element (REE) deposits enriched in heavy REEs such as dysprosium.^[37] Australia, Myanmar, and the United States follow as significant holders, though their shares are smaller and often tied to specific heavy REE-enriched sites rather than total REE volumes.^[38] China's major dysprosium deposits are primarily ionic adsorption clays in southern provinces including Jiangxi, Guangdong, and Fujian, which uniquely concentrate heavy rare earth elements like dysprosium through weathering processes. These deposits supply the bulk of global dysprosium resources outside conventional hard-rock mining. The Bayan Obo site in Inner Mongolia, the world's largest REE deposit, contains dysprosium as a minor component within its vast bastnäsite and monazite ores, contributing to China's overall reserves despite its predominance in light REEs.^[39]^[40] In Australia, the Browns Range project in Western Australia hosts xenotime-bearing deposits exceptionally rich in dysprosium and terbium, with resource estimates highlighting its potential as a non-Chinese heavy REE source. The Mount Weld carbonatite deposit, operated by Lynas Rare Earths, includes dysprosium within its REE inventory, though at lower concentrations compared to Browns Range.^[41]^[37] Myanmar's ionic clay deposits in regions like Kachin state have emerged as key heavy REE sources, analogous to China's, with empirical assays confirming elevated dysprosium levels amid recent exploration upticks. In the United States, the Fluorspar property in Utah has verified neodymium-dysprosium enrichments through 2024–2025 fieldwork, indicating potential for domestic heavy REE recovery from unconventional sources.^[42]^[43]

Production

Extraction and separation processes

Dysprosium is extracted from rare earth element (REE) ores, primarily monazite, bastnäsite, and xenotime, via initial beneficiation to concentrate REE-bearing minerals. This involves crushing and grinding the ore, followed by froth flotation using collectors such as fatty acids to separate REE phosphates or carbonates from gangue materials like silica and iron oxides, yielding a concentrate with 30-70% total REE oxides.^[44]^[45] The concentrate undergoes hydrometallurgical processing, typically sulfuric acid roasting at 200-300°C to convert insoluble REE phosphates to sulfates, followed by water or acid leaching to solubilize over 90% of the REEs into aqueous solution as sulfates or chlorides; hydrochloric acid leaching is also employed for certain ores like xenotime, achieving selective recovery of heavy REEs including dysprosium.^[46]^[47] Impurities such as thorium and uranium are removed via precipitation or solvent extraction prior to REE separation. Due to the chemical similarity of REEs, dysprosium isolation relies on multi-stage solvent extraction, where acidic organophosphorus extractants like di-(2-ethylhexyl)phosphoric acid (D2EHPA) in kerosene selectively partition dysprosium ions from nitric or hydrochloric acid feeds into the organic phase, exploiting differences in distribution coefficients (e.g., higher for heavy REEs like Dy over Nd).^[48]^[49] The process includes extraction, scrubbing with dilute acid to purify the loaded organic phase, and stripping with stronger acid to recover dysprosium, often requiring 100-200 stages for >99% purity; yield losses occur during heavy REE fractionation due to co-extraction of neighbors like terbium and holmium.^[50] The extracted dysprosium is precipitated as oxalate, filtered, and calcined to dysprosium oxide (Dy₂O₃) at 800-1000°C. Dysprosium metal is obtained by metallothermic reduction of anhydrous DyF₃ with calcium at 1200-1400°C under vacuum, producing crude metal that is vacuum-distilled to remove calcium and achieve >99.9% purity.^[51] Electrolysis of DyF₃ in molten fluoride salts (e.g., LiF-DyF₃ eutectic) at tungsten cathodes offers an alternative, with cathodic reduction of Dy³⁺ to Dy in a single three-electron step, though it is less common industrially due to electrode corrosion and energy demands exceeding 10 kWh/kg.^[52]^[53] These reduction methods are highly energy-intensive, with overall process efficiencies limited by separation losses and thermal requirements.^[54]

Global production leaders

China dominates global dysprosium production, accounting for over 99% of processed dysprosium oxide as of 2025, with refined output concentrated in facilities controlled by state-backed enterprises like China Northern Rare Earth Group and China Southern Rare Earth Group.^[55]^[40] Global production of dysprosium oxide exceeded 2,300 metric tons in 2024, primarily as rare earth oxide (REO) equivalent, driven by extraction from bastnäsite, monazite, and ion-adsorption clay deposits, though nearly all separation and refining occurs within China due to its technological and cost advantages in solvent extraction processes.^[56] This monopoly creates supply chain vulnerabilities, as disruptions in Chinese processing—such as export controls implemented in October 2025—can halt global availability of separated dysprosium despite mining in other regions.^[57]^[58] Non-Chinese production remains marginal, with Australia-based Lynas Rare Earths operating the Mount Weld mine and Malaysian processing facility yielding small volumes of separated dysprosium oxide, estimated at under 100 tonnes annually as of 2024.^[59] The United States' MP Materials, via its Mountain Pass mine, focuses primarily on light rare earths but has initiated limited heavy rare earth separation including dysprosium, producing negligible quantities relative to China in 2024.^[37] Myanmar contributes via ion-adsorption deposits exported largely to China for processing, adding to feedstock but not refined output outside Chinese control.^[59] Recycling from end-of-life magnets and scrap represents less than 5% of supply, constrained by collection inefficiencies and technical challenges in recovering high-purity dysprosium.^[39] Production volumes have ramped up since 2010, correlating with surging demand for dysprosium-doped neodymium-iron-boron magnets in electric vehicles and wind turbines, which require 1-2% dysprosium for thermal stability; global output tripled from under 1,000 tonnes REO equivalent in 2010 to current levels, yet diversification efforts by Western producers have failed to erode China's refining hegemony.^[60]^[61] This processing concentration amplifies geopolitical risks, as non-Chinese mined concentrates often ship to China for final separation, linking output security to Beijing's policy decisions.^[62]^[63]

Applications

Industrial and technological uses

Dysprosium is incorporated as an additive in neodymium-iron-boron (NdFeB) permanent magnets at concentrations typically ranging from 1% to 5% by weight, where it substitutes for neodymium to form a core-shell structure that significantly enhances intrinsic coercivity and resistance to demagnetization at elevated temperatures.^[3]^[64] This improvement allows magnets to maintain performance in applications requiring thermal stability, such as electric vehicle motors operating at up to 150–180°C and direct-drive wind turbine generators exposed to variable environmental conditions.^[65]^[66] The addition also elevates the effective Curie temperature range in these alloys, extending operational limits beyond those of undoped NdFeB, which has a base Curie point around 310–400°C but suffers coercivity loss at lower thresholds without dysprosium.^[67] In data storage, dysprosium-enhanced NdFeB magnets are essential for the voice coil actuators in hard disk drives (HDDs), providing the high coercivity needed for reliable positioning in compact, high-speed mechanisms.^[68] Beyond magnets, dysprosium serves as a dopant in laser materials, notably in dysprosium-doped yttrium aluminum garnet (Dy:YAG) crystals, which enable efficient four-level laser operation in the visible spectrum, particularly yellow emissions around 577 nm suitable for medical and spectroscopy applications.^[69] Dysprosium ions (Dy³⁺) act as activators in phosphors for white light-emitting diodes (LEDs), where concentrations of 1–3 mol% produce complementary blue (480 nm) and yellow (575 nm) emissions under near-UV excitation, achieving color temperatures around 5000–6500 K with quantum efficiencies exceeding 70% in optimized hosts like silicates or aluminates.^[70]^[71] In nuclear technology, dysprosium oxide-nickel cermets are employed in control rods for thermal reactors, leveraging dysprosium's high thermal neutron capture cross-section (over 1000 barns) to absorb neutrons effectively without significant swelling or gas evolution under irradiation.^[8]^[72]

Military and strategic applications

Dysprosium enhances the performance of neodymium-iron-boron permanent magnets by increasing their intrinsic coercivity and thermal stability, enabling reliable operation in high-temperature military environments where standard magnets would fail.^[3] These dysprosium-alloyed magnets are integral to actuators, sensors, and electric motors in platforms like the F-35 Lightning II fighter jet, which requires over 400 kilograms of rare earth elements including dysprosium to withstand operational stresses exceeding 150°C.^[73] Similarly, they support precision-guided munitions such as the Joint Direct Attack Munition (JDAM), where dysprosium contributes to the targeting and guidance systems' resilience under aerodynamic heating and vibration.^[74] In radar and avionics systems, dysprosium's role in heat-resistant magnets ensures signal processing and beam steering maintain accuracy during sustained high-power operations, as seen in advanced military radar arrays.^[75] For naval applications, these magnets power propulsion and control systems in submarines, where compact, high-torque performance is essential for stealth and maneuverability.^[76] Dysprosium titanate serves as a neutron-absorbing material in control rods for thermal nuclear reactors, leveraging its high thermal neutron capture cross-section (approximately 1,100 barns for Dy-164) and low swelling under neutron flux, which supports reactivity control in compact naval reactor designs.^[77] The U.S. Department of Defense classifies dysprosium as a critical material for national security, with initiatives underway to establish stockpiles valued at up to $1 billion in rare earths to mitigate supply disruptions, as domestic reserves remain depleted and production lags behind defense demands.^[78]^[79]

Supply Chain and Geopolitics

Supply dependencies and risks

China maintains near-total control over dysprosium refining, processing approximately 99.9% of global supply as of 2025, which exposes downstream industries to risks from unilateral export policies.^[55] In April 2025, China imposed export restrictions on dysprosium and six other rare earth elements in response to U.S. tariffs, requiring special licenses that could delay or halt shipments to foreign buyers.^[80] Further controls announced on October 9, 2025, targeted medium and heavy rare earths, intensifying supply concentration risks amid ongoing trade tensions.^[62] This dominance stems from China's integrated mining-to-refining infrastructure, where over 90% of heavy rare earth separation capacity resides, enabling rapid deployment of quotas or bans that historical precedents, such as 2010 restrictions, have shown can spike prices by over 500%.^[81]^[82] Myanmar's role as an emerging source for heavy rare earth ores, including dysprosium-bearing minerals, introduces additional geopolitical volatility due to ongoing civil conflict following the 2021 coup.^[83] Rebel groups and ethnic armed organizations control key mining areas in northern regions like Kachin State, where illicit operations supply up to 50% of China's heavy rare earth imports, but disruptions from fighting have already led to intermittent halts in 2025 exports.^[84]^[85] This instability amplifies supply risks, as Myanmar's ion-adsorption clay deposits are low-cost but unregulated, with no viable alternatives scaling quickly to offset potential shutdowns.^[86] Scenario analyses indicate that export bans or prolonged disruptions could severely constrain dysprosium availability, with electric vehicle demand alone projected to exceed historical supply levels by 2025 under moderate growth assumptions.^[87] Modeling from the International Energy Agency and others forecasts three- to seven-fold increases in rare earth demand by 2040 for clean energy technologies, outpacing diversified mining capacity and leading to primary supply deficits unless processing bottlenecks are resolved.^[88] U.S. and EU diversification initiatives, including subsidies under the 2022 Inflation Reduction Act, have spurred investments in domestic separation facilities but remain nascent, with non-Chinese refining capacity under 10% of global needs as of 2025 and timelines extending beyond 2030 for meaningful scale-up.^[89] Recycling offers limited mitigation, with global rates for rare earth elements hovering below 1% and dysprosium recovery efficiencies in end-of-life magnets typically under 50% due to technical challenges in separation and low e-waste collection yields.^[90] Projections estimate that even optimistic recycling expansions would cover only 25-40% of demand gaps by 2040, failing to offset primary deficits driven by exponential growth in magnet applications.^[91] Overreliance on concentrated sources thus perpetuates systemic vulnerabilities, as evidenced by price volatility exceeding 300% in response to prior controls, underscoring the need for accelerated, geopolitically resilient alternatives.^[92]

Market trends and recent developments

Dysprosium prices exhibited significant volatility in 2024 and 2025, with dysprosium oxide trading as low as $220–270 per kg in December 2024 before surging to $780 per kg by mid-2025 amid supply constraints and heightened demand.^[93]^[94] This +121% year-to-date increase in 2025 reflected strategic stockpiling and export controls rather than purely fundamental demand, though prices stabilized around $275 per kg by September 2025 in Northeast Asia.^[95] Global dysprosium market demand reached approximately $1 billion in 2024, driven primarily by its role in high-performance neodymium-iron-boron magnets for electric vehicles (EVs) and wind turbines, which account for over 70% of consumption.^[60] Projections indicate the market could expand to $1.75 billion by 2035 at a 5.2% CAGR, though aggressive clean energy deployment may triple magnetic rare earth needs to 176 kilotons annually by then, intensifying pressure on dysprosium supplies.^[96]^[97] Efforts to diversify supply included Lynas Rare Earths' August 2025 capital raise of A$750 million ($490 million) to expand operations at Mt Weld in Australia and integrate new processing in Kalgoorlie, aiming to boost non-Chinese heavy rare earth output as part of its Lynas 2025 growth plan.^[98]^[99] In the United States, Energy Fuels achieved a milestone in August 2025 by producing the first high-purity (99.9%) dysprosium oxide domestically at its Utah facility, with plans for scaled heavy rare earth separation potentially starting in 2027 pending investment decisions.^[100]^[101] Geopolitical tensions exacerbated supply risks, as China—controlling over 90% of global dysprosium processing—imposed export controls in April 2025 on seven rare earth elements including dysprosium, followed by expanded licensing requirements in October 2025 effective November 8, targeting embedded products and equipment.^[102]^[103] These measures, linked to U.S. tariffs, have tightened chains and prompted Western diversification, though short-term disruptions persist.^[104] Supply-demand models highlight vulnerabilities in green transitions, with dysprosium reserves potentially depleting globally by 2045 under 1.5°C scenarios requiring massive EV and wind scaling, potentially creating shortfalls equivalent to 77 million EVs or 3,040 GW of wind capacity.^[105] Such constraints challenge assumptions of seamless electrification and turbine deployment, as dysprosium's scarcity in high-temperature magnets cannot be easily substituted without performance losses, per analyses from the International Energy Agency and others.^[106]^[107] Recycling and efficiency gains could mitigate up to 35% of demand by 2050, but primary supply gaps remain a feasibility barrier absent accelerated non-Chinese mining.^[108]

Safety and Environmental Impact

Health and handling precautions

Dysprosium and its compounds demonstrate low acute oral toxicity, with reported LD50 values exceeding 2,000 mg/kg in rats for dysprosium nitrate and greater than 5,000 mg/kg for dysprosium oxide.^[109]^[110] Soluble dysprosium salts are mildly toxic upon ingestion, while insoluble forms show negligible effects.^[17] Dysprosium has no known essential biological role in humans or other organisms.^[8] Inhalation of dysprosium fines or dust poses the primary health risk during handling, with potential for respiratory irritation and, upon chronic exposure, rare earth pneumoconiosis characterized by pulmonary fibrosis similar to effects observed with other rare earth elements.^[111]^[112] No specific permissible exposure limits (PELs) have been established by OSHA or NIOSH for dysprosium, necessitating reliance on general industrial hygiene practices.^[113] Handling precautions include engineering controls such as local exhaust ventilation to minimize airborne dust, along with personal protective equipment comprising NIOSH/MSHA-approved respirators for potential exposure exceedances, chemical-resistant gloves, protective clothing, and safety goggles to prevent skin or eye contact.^[110]^[109] For radioactive isotopes like dysprosium-166, used in medical or nuclear applications, additional handling must adhere to regulations from bodies such as the Nuclear Regulatory Commission, incorporating radiation shielding, dosimetry monitoring, and licensed personnel requirements.^[114]

Ecological and mining impacts

Dysprosium extraction, primarily as a byproduct of rare earth element (REE) mining from monazite and bastnasite ores, generates substantial tailings laden with radioactive thorium and uranium decay products, posing long-term ecological risks through groundwater leaching and sediment contamination.^[115] Processing these ores often results in acid mine drainage, where sulfuric acid from sulfide oxidation mobilizes heavy metals and REEs into waterways, altering pH levels and impairing aquatic ecosystems.^[116] In monazite-rich deposits, tailings radioactivity exceeds background levels, with thorium concentrations in waste ponds reaching thousands of becquerels per kilogram, necessitating isolation to prevent radon emanation and soil penetration.^[117] At China's Bayan Obo mine, the world's largest REE operation supplying much of global dysprosium, open-pit activities have caused widespread soil erosion and chemical leaching into the Yellow River basin, with documented fluoride and heavy metal spikes in local sediments as of 2025.^[118] Lax regulatory enforcement has permitted untreated tailings discharge, elevating REE concentrations in surrounding farmland soils by factors of 10-50 times natural baselines, compared to stricter containment standards in Western operations like those in Australia.^[119] ^[120] This disparity underscores causal pathways from unenforced waste management to persistent pollution hotspots, where alkaline tailings neutralize acids but mobilize REEs via runoff during monsoons. REEs from mining effluents bioaccumulate in soil microbiota and plants, facilitating trophic transfer through agricultural irrigation, with dysprosium and other heavy REEs detected at elevated levels in root vegetables near extraction sites.^[121] Empirical sampling reveals mean REE contents in mine-adjacent crops 5-20 times higher than reference areas, driven by adsorption to clay particles and pH-dependent uptake, potentially amplifying concentrations up the food web despite observed biodilution in higher trophic levels.^[122] ^[123] Such pathways highlight the indirect ecological costs of REE mining embedded in supply chains for low-carbon technologies, where unmitigated runoff undermines biodiversity in contaminated watersheds. Efforts to mitigate impacts include REE recovery from tailings and recycling dysprosium from end-of-life magnets, which could offset up to 40% of primary demand by 2050 under optimized scenarios, reducing associated waste volumes.^[124] However, recycling scalability remains constrained by low collection efficiencies—currently below 1% globally for NdFeB sources—and energy-intensive separation processes that limit net environmental gains without widespread infrastructure.^[125] These limitations perpetuate reliance on high-impact mining, particularly in regions with weaker oversight, amplifying the causal footprint of dysprosium supply for "green" applications.^[126]