Lead Lead () is a chemical element; it has Chemical symbol, symbol Pb (from Latin ) and atomic number 82. It is a Heavy metal (elements), heavy metal that is density, denser than most common materials. Lead is Mohs scale, soft and Ductility, malleabl ...

(₈₂Pb) has four

observationally stable Stable nuclides are isotopes of a chemical element whose nucleons are in a configuration that does not permit them the surplus energy required to produce a radioactive emission. The nuclei of such isotopes are not radioactive and unlike radionuc ...

isotope Isotopes are distinct nuclear species (or ''nuclides'') of the same chemical element. They have the same atomic number (number of protons in their Atomic nucleus, nuclei) and position in the periodic table (and hence belong to the same chemica ...

s: ²⁰⁴Pb, ²⁰⁶Pb, ²⁰⁷Pb, ²⁰⁸Pb. Lead-204 is entirely a

primordial nuclide In geochemistry, geophysics and nuclear physics, primordial nuclides, also known as primordial isotopes, are nuclides found on Earth that have existed in their current form since before Earth was formed. Primordial nuclides were present in the ...

and is not a radiogenic nuclide. The three isotopes lead-206, lead-207, and lead-208 represent the ends of three

decay chain In nuclear science a decay chain refers to the predictable series of radioactive disintegrations undergone by the nuclei of certain unstable chemical elements. Radioactive isotopes do not usually decay directly to stable isotopes, but rather ...

s: the

uranium series In nuclear science a decay chain refers to the predictable series of radioactive disintegrations undergone by the nuclei of certain unstable chemical elements. Radioactive isotopes do not usually decay directly to stable isotopes, but rather ...

(or radium series), the

actinium series In nuclear science a decay chain refers to the predictable series of radioactive disintegrations undergone by the nuclei of certain unstable chemical elements. Radioactive isotopes do not usually decay directly to stable isotopes, but rather ...

, and the

thorium series In nuclear science a decay chain refers to the predictable series of radioactive disintegrations undergone by the nuclei of certain unstable chemical elements. Radioactive isotopes do not usually decay directly to stable isotopes, but rather ...

, respectively; a fourth decay chain, the

neptunium series In nuclear science a decay chain refers to the predictable series of radioactive decay, radioactive disintegrations undergone by the nuclei of certain unstable chemical elements. Radionuclide, Radioactive isotopes do not usually decay directly ...

, terminates with the

thallium Thallium is a chemical element; it has Symbol (chemistry), symbol Tl and atomic number 81. It is a silvery-white post-transition metal that is not found free in nature. When isolated, thallium resembles tin, but discolors when exposed to air. Che ...

isotope ²⁰⁵Tl. The three series terminating in lead represent the decay chain products of long-lived primordial ²³⁸U, ²³⁵U, and ²³²Th. Each isotope also occurs, to some extent, as primordial isotopes that were made in supernovae, rather than radiogenically as daughter products. The fixed ratio of lead-204 to the primordial amounts of the other lead isotopes may be used as the baseline to estimate the extra amounts of radiogenic lead present in rocks as a result of decay from uranium and thorium. (See lead–lead dating and

uranium–lead dating Uranium–lead dating, abbreviated U–Pb dating, is one of the oldest and most refined of the radiometric dating schemes. It can be used to date rocks that formed and crystallised from about 1 million years to over 4.5 billion years ago with routi ...

.) The longest-lived radioisotopes are ²⁰⁵Pb with a

half-life Half-life is a mathematical and scientific description of exponential or gradual decay. Half-life, half life or halflife may also refer to: Film * Half-Life (film), ''Half-Life'' (film), a 2008 independent film by Jennifer Phang * ''Half Life: ...

of 17.3 million years and ²⁰²Pb with a half-life of 52,500 years. A shorter-lived naturally occurring radioisotope, ²¹⁰Pb with a half-life of 22.2 years, is useful for studying the

sedimentation Sedimentation is the deposition of sediments. It takes place when particles in suspension settle out of the fluid in which they are entrained and come to rest against a barrier. This is due to their motion through the fluid in response to th ...

chronology of environmental samples on time scales shorter than 100 years. The relative abundances of the four stable isotopes are approximately 1.5%, 24%, 22%, and 52.5%, combining to give a standard atomic weight (abundance-weighted average of the stable isotopes) of 207.2(1). Lead is the element with the heaviest stable isotope, ²⁰⁸Pb. (The more massive ²⁰⁹Bi, long considered to be stable, actually has a half-life of 2.01×10¹⁹ years.) ²⁰⁸Pb is also a doubly magic isotope, as it has 82

proton A proton is a stable subatomic particle, symbol , Hydron (chemistry), H+, or 1H+ with a positive electric charge of +1 ''e'' (elementary charge). Its mass is slightly less than the mass of a neutron and approximately times the mass of an e ...

s and 126

neutron The neutron is a subatomic particle, symbol or , that has no electric charge, and a mass slightly greater than that of a proton. The Discovery of the neutron, neutron was discovered by James Chadwick in 1932, leading to the discovery of nucle ...

s. It is the heaviest doubly magic nuclide known. A total of 43 lead isotopes are now known, including very unstable synthetic species. The four primordial isotopes of lead are all

, meaning that they are predicted to undergo radioactive decay but no decay has been observed yet. These four isotopes are predicted to undergo

alpha decay Alpha decay or α-decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle (helium nucleus). The parent nucleus transforms or "decays" into a daughter product, with a mass number that is reduced by four and an a ...

and become isotopes of mercury which are themselves radioactive or observationally stable. In its fully ionized state, the

beta decay In nuclear physics, beta decay (β-decay) is a type of radioactive decay in which an atomic nucleus emits a beta particle (fast energetic electron or positron), transforming into an isobar of that nuclide. For example, beta decay of a neutron ...

of isotope ²¹⁰Pb does not release a free electron; the generated electron is instead captured by the atom's empty orbitals.

List of isotopes

, -id=Lead-178 , rowspan=2, ¹⁷⁸Pb , rowspan=2, , rowspan=2 style="text-align:right" , 82 , rowspan=2 style="text-align:right" , 96 , rowspan=2, 178.003836(25) , rowspan=2, 250(80) μs , α , ¹⁷⁴Hg , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , β⁺? , ¹⁷⁸Tl , -id=Lead-179 , ¹⁷⁹Pb , , style="text-align:right" , 82 , style="text-align:right" , 97 , 179.002(87) , 2.7(2) ms , α , ¹⁷⁵Hg , (9/2−) , , , -id=Lead-180 , ¹⁸⁰Pb , , style="text-align:right" , 82 , style="text-align:right" , 98 , 179.997916(13) , 4.1(3) ms , α , ¹⁷⁶Hg , 0+ , , , -id=Lead-181 , rowspan=2, ¹⁸¹Pb , rowspan=2, , rowspan=2 style="text-align:right" , 82 , rowspan=2 style="text-align:right" , 99 , rowspan=2, 180.996661(91) , rowspan=2, 39.0(8) ms , α , ¹⁷⁷Hg , rowspan=2, (9/2−) , rowspan=2, , rowspan=2, , - , β⁺? , ¹⁸¹Tl , -id=Lead-182 , rowspan=2, ¹⁸²Pb , rowspan=2, , rowspan=2 style="text-align:right" , 82 , rowspan=2 style="text-align:right" , 100 , rowspan=2, 181.992674(13) , rowspan=2, 55(5) ms , α , ¹⁷⁸Hg , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , β⁺? , ¹⁸²Tl , -id=Lead-183 , rowspan=2, ¹⁸³Pb , rowspan=2, , rowspan=2 style="text-align:right" , 82 , rowspan=2 style="text-align:right" , 101 , rowspan=2, 182.991863(31) , rowspan=2, 535(30) ms , α , ¹⁷⁹Hg , rowspan=2, 3/2− , rowspan=2, , rowspan=2, , - , β⁺? , ¹⁸³Tl , -id=Lead-183m , rowspan=3 style="text-indent:1em" , ^183mPb , rowspan=3, , rowspan=3 colspan="3" style="text-indent:2em" , 94(8) keV , rowspan=3, 415(20) ms , α , ¹⁷⁹Hg , rowspan=3, 13/2+ , rowspan=3, , rowspan=3, , - , β⁺? , ¹⁸³Tl , - , IT? , ¹⁸³Pb , -id=Lead-184 , rowspan=2, ¹⁸⁴Pb , rowspan=2, , rowspan=2 style="text-align:right" , 82 , rowspan=2 style="text-align:right" , 102 , rowspan=2, 183.988136(14) , rowspan=2, 490(25) ms , α (80%) , ¹⁸⁰Hg , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , β⁺? (20%) , ¹⁸⁴Tl , -id=Lead-185 , rowspan=2, ¹⁸⁵Pb , rowspan=2, , rowspan=2 style="text-align:right" , 82 , rowspan=2 style="text-align:right" , 103 , rowspan=2, 184.987610(17) , rowspan=2, 6.3(4) s , β⁺ (66%) , ¹⁸⁵Tl , rowspan=2, 3/2− , rowspan=2, , rowspan=2, , - , α (34%) , ¹⁸¹Hg , -id=Lead-185m , rowspan=2 style="text-indent:1em" , ^185mPbOrder of ground state and isomer is uncertain. , rowspan=2, , rowspan=2 colspan="3" style="text-indent:2em" , 70(50) keV , rowspan=2, 4.07(15) s , α (50%) , ¹⁸¹Hg , rowspan=2, 13/2+ , rowspan=2, , rowspan=2, , - , β⁺? (50%) , ¹⁸⁵Tl , -id=Lead-186 , rowspan=2, ¹⁸⁶Pb , rowspan=2, , rowspan=2 style="text-align:right" , 82 , rowspan=2 style="text-align:right" , 104 , rowspan=2, 185.984239(12) , rowspan=2, 4.82(3) s , β⁺? (60%) , ¹⁸⁶Tl , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , α (40%) , ¹⁸²Hg , -id=Lead-187 , rowspan=2, ¹⁸⁷Pb , rowspan=2, , rowspan=2 style="text-align:right" , 82 , rowspan=2 style="text-align:right" , 105 , rowspan=2, 186.9839108(55) , rowspan=2, 15.2(3) s , β⁺ (90.5%) , ¹⁸⁷Tl , rowspan=2, 3/2− , rowspan=2, , rowspan=2, , - , α (9.5%) , ¹⁸³Hg , -id=Lead-187m , rowspan=2 style="text-indent:1em" , ^187mPb , rowspan=2, , rowspan=2 colspan="3" style="text-indent:2em" , 19(10) keV , rowspan=2, 18.3(3) s , β⁺ (88%) , ¹⁸⁷Tl , rowspan=2, 13/2+ , rowspan=2, , rowspan=2, , - , α (12%) , ¹⁸³Hg , -id=Lead-188 , rowspan=2, ¹⁸⁸Pb , rowspan=2, , rowspan=2 style="text-align:right" , 82 , rowspan=2 style="text-align:right" , 106 , rowspan=2, 187.980879(11) , rowspan=2, 25.1(1) s , β⁺ (91.5%) , ¹⁸⁸Tl , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , α (8.5%) , ¹⁸⁴Hg , -id=Lead-188m1 , style="text-indent:1em" , ^188m1Pb , , colspan="3" style="text-indent:2em" , 2577.2(4) keV , 800(20) ns , IT , ¹⁸⁸Pb , 8− , , , -id=Lead-188m2 , style="text-indent:1em" , ^188m2Pb , , colspan="3" style="text-indent:2em" , 2709.8(5) keV , 94(12) ns , IT , ¹⁸⁸Pb , 12+ , , , -id=Lead-188m3 , style="text-indent:1em" , ^188m3Pb , , colspan="3" style="text-indent:2em" , 4783.4(7) keV , 440(60) ns , IT , ¹⁸⁸Pb , (19−) , , , -id=Lead-189 , rowspan=2, ¹⁸⁹Pb , rowspan=2, , rowspan=2 style="text-align:right" , 82 , rowspan=2 style="text-align:right" , 107 , rowspan=2, 188.980844(15) , rowspan=2, 39(8) s , β⁺ (99.58%) , ¹⁸⁹Tl , rowspan=2, 3/2− , rowspan=2, , rowspan=2, , - , α (0.42%) , ¹⁸⁵Hg , -id=Lead-189m1 , rowspan=3 style="text-indent:1em" , ^189m1Pb , rowspan=3, , rowspan=3 colspan="3" style="text-indent:2em" , 40(4) keV , rowspan=3, 50.5(21) s , β⁺ (99.6%) , ¹⁸⁹Tl , rowspan=3, 13/2+ , rowspan=3, , rowspan=3, , - , α (0.4%) , ¹⁸⁵Hg , - , IT? , ¹⁸⁹Pb , -id=Lead-189m2 , style="text-indent:1em" , ^189m2Pb , , colspan="3" style="text-indent:2em" , 2475(4) keV , 26(5) μs , IT , ¹⁸⁹Pb , 31/2− , , , -id=Lead-190 , rowspan=2, ¹⁹⁰Pb , rowspan=2, , rowspan=2 style="text-align:right" , 82 , rowspan=2 style="text-align:right" , 108 , rowspan=2, 189.978082(13) , rowspan=2, 71(1) s , β⁺ (99.60%) , ¹⁹⁰Tl , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , α (0.40%) , ¹⁸⁶Hg , -id=Lead-190m1 , style="text-indent:1em" , ^190m1Pb , , colspan="3" style="text-indent:2em" , 2614.8(8) keV , 150(14) ns , IT , ¹⁹⁰Pb , 10+ , , , -id=Lead-190m2 , style="text-indent:1em" , ^190m2Pb , , colspan="3" style="text-indent:2em" , 2665(50)# keV , 24.3(21) μs , IT , ¹⁹⁰Pb , (12+) , , , -id=Lead-190m3 , style="text-indent:1em" , ^190m3Pb , , colspan="3" style="text-indent:2em" , 2658.2(8) keV , 7.7(3) μs , IT , ¹⁹⁰Pb , 11− , , , -id=Lead-191 , rowspan=2, ¹⁹¹Pb , rowspan=2, , rowspan=2 style="text-align:right" , 82 , rowspan=2 style="text-align:right" , 109 , rowspan=2, 190.9782165(71) , rowspan=2, 1.33(8) min , β⁺ (99.49%) , ¹⁹¹Tl , rowspan=2, 3/2− , rowspan=2, , rowspan=2, , - , α (0.51%) , ¹⁸⁷Hg , -id=Lead-191m1 , rowspan=2 style="text-indent:1em" , ^191m1Pb , rowspan=2, , rowspan=2 colspan="3" style="text-indent:2em" , 58(10) keV , rowspan=2, 2.18(8) min , β⁺ (99.98%) , ¹⁹¹Tl , rowspan=2, 13/2+ , rowspan=2, , rowspan=2, , - , α (0.02%) , ¹⁸⁷Hg , -id=Lead-191m2 , style="text-indent:1em" , ^191m2Pb , , colspan="3" style="text-indent:2em" , 2659(10) keV , 180(80) ns , IT , ¹⁹¹Pb , 33/2+ , , , -id=Lead-192 , rowspan=2, ¹⁹²Pb , rowspan=2, , rowspan=2 style="text-align:right" , 82 , rowspan=2 style="text-align:right" , 110 , rowspan=2, 191.9757896(61) , rowspan=2, 3.5(1) min , β⁺ (99.99%) , ¹⁹²Tl , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , α (0.0059%) , ¹⁸⁸Hg , -id=Lead-192m1 , style="text-indent:1em" , ^192m1Pb , , colspan="3" style="text-indent:2em" , 2581.1(1) keV , 166(6) ns , IT , ¹⁹²Pb , 10+ , , , -id=Lead-192m2 , style="text-indent:1em" , ^192m2Pb , , colspan="3" style="text-indent:2em" , 2625.1(11) keV , 1.09(4) μs , IT , ¹⁹²Pb , 12+ , , , -id=Lead-192m3 , style="text-indent:1em" , ^192m3Pb , , colspan="3" style="text-indent:2em" , 2743.5(4) keV , 756(14) ns , IT , ¹⁹²Pb , 11− , , , -id=Lead-193 , ¹⁹³Pb , , style="text-align:right" , 82 , style="text-align:right" , 111 , 192.976136(11) , 4# min , β⁺? , ¹⁹³Tl , 3/2−# , , , -id=Lead-193m1 , style="text-indent:1em" , ^193m1Pb , , colspan="3" style="text-indent:2em" , 93(12) keV , 5.8(2) min , β⁺ , ¹⁹³Tl , 13/2+ , , , -id=Lead-193m2 , style="text-indent:1em" , ^193m2Pb , , colspan="3" style="text-indent:2em" , 2707(13) keV , 180(15) ns , IT , ¹⁹³Pb , 33/2+ , , , -id=Lead-194 , rowspan=2, ¹⁹⁴Pb , rowspan=2, , rowspan=2 style="text-align:right" , 82 , rowspan=2 style="text-align:right" , 112 , rowspan=2, 193.974012(19) , rowspan=2, 10.7(6) min , β⁺ , ¹⁹⁴Tl , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , α (7.3×10⁻⁶%) , ¹⁹⁰Hg , -id=Lead-194m1 , style="text-indent:1em" , ^194m1Pb , , colspan="3" style="text-indent:2em" , 2628.1(4) keV , 370(13) ns , IT , ¹⁹⁴Pb , 12+ , , , -id=Lead-194m2 , style="text-indent:1em" , ^194m2Pb , , colspan="3" style="text-indent:2em" , 2933.0(4) keV , 133(7) ns , IT , ¹⁹⁴Pb , 11− , , , -id=Lead-195 , ¹⁹⁵Pb , , style="text-align:right" , 82 , style="text-align:right" , 113 , 194.9745162(55) , 15.0(14) min , β⁺ , ¹⁹⁵Tl , 3/2- , , , -id=Lead-195m1 , rowspan=2 style="text-indent:1em" , ^195m1Pb , rowspan=2, , rowspan=2 colspan="3" style="text-indent:2em" , 202.9(7) keV , rowspan=2, 15.0(12) min , β⁺ , ¹⁹⁵Tl , rowspan=2, 13/2+ , rowspan=2, , rowspan=2, , - , IT? , ¹⁹⁵Pb , -id=Lead-195m2 , style="text-indent:1em" , ^195m2Pb , , colspan="3" style="text-indent:2em" , 1759.0(7) keV , 10.0(7) μs , IT , ¹⁹⁵Pb , 21/2− , , , -id=Lead-195m3 , style="text-indent:1em" , ^195m3Pb , , colspan="3" style="text-indent:2em" , 2901.7(8) keV , 95(20) ns , IT , ¹⁹⁵Pb , 33/2+ , , , -id=Lead-196 , rowspan=2, ¹⁹⁶Pb , rowspan=2, , rowspan=2 style="text-align:right" , 82 , rowspan=2 style="text-align:right" , 114 , rowspan=2, 195.9727876(83) , rowspan=2, 37(3) min , β⁺ , ¹⁹⁶Tl , rowspan=2, 0+ , rowspan=2, , rowspan=2, , - , α (<3×10⁻⁵%) , ¹⁹²Hg , -id=Lead-196m1 , style="text-indent:1em" , ^196m1Pb , , colspan="3" style="text-indent:2em" , 1797.51(14) keV , 140(14) ns , IT , ¹⁹⁶Pb , 5− , , , -id=Lead-196m2 , style="text-indent:1em" , ^196m2Pb , , colspan="3" style="text-indent:2em" , 2694.6(3) keV , 270(4) ns , IT , ¹⁹⁶Pb , 12+ , , , -id=Lead-197 , ¹⁹⁷Pb , , style="text-align:right" , 82 , style="text-align:right" , 115 , 196.9734347(52) , 8.1(17) min , β⁺ , ¹⁹⁷Tl , 3/2− , , , -id=Lead-197m1 , rowspan=2 style="text-indent:1em" , ^197m1Pb , rowspan=2, , rowspan=2 colspan="3" style="text-indent:2em" , 319.31(11) keV , rowspan=2, 42.9(9) min , β⁺ (81%) , ¹⁹⁷Tl , rowspan=2, 13/2+ , rowspan=2, , rowspan=2, , - , IT (19%) , ¹⁹⁷Pb , -id=Lead-197m2 , style="text-indent:1em" , ^197m2Pb , , colspan="3" style="text-indent:2em" , 1914.10(25) keV , 1.15(20) μs , IT , ¹⁹⁷Pb , 21/2− , , , -id=Lead-198 , ¹⁹⁸Pb , , style="text-align:right" , 82 , style="text-align:right" , 116 , 197.9720155(94) , 2.4(1) h , β⁺ , ¹⁹⁸Tl , 0+ , , , -id=Lead-198m1 , style="text-indent:1em" , ^198m1Pb , , colspan="3" style="text-indent:2em" , 2141.4(4) keV , 4.12(7) μs , IT , ¹⁹⁸Pb , 7− , , , -id=Lead-198m2 , style="text-indent:1em" , ^198m2Pb , , colspan="3" style="text-indent:2em" , 2231.4(5) keV , 137(10) ns , IT , ¹⁹⁸Pb , 9− , , , -id=Lead-198m3 , style="text-indent:1em" , ^198m3Pb , , colspan="3" style="text-indent:2em" , 2821.7(6) keV , 212(4) ns , IT , ¹⁹⁸Pb , 12+ , , , -id=Lead-199 , ¹⁹⁹Pb , , style="text-align:right" , 82 , style="text-align:right" , 117 , 198.9729126(73) , 90(10) min , β⁺ , ¹⁹⁹Tl , 3/2− , , , -id=Lead-199m1 , rowspan=2 style="text-indent:1em" , ^199m1Pb , rowspan=2, , rowspan=2 colspan="3" style="text-indent:2em" , 429.5(27) keV , rowspan=2, 12.2(3) min , IT , ¹⁹⁹Pb , rowspan=2, (13/2+) , rowspan=2, , rowspan=2, , - , β⁺? , ¹⁹⁹Tl , -id=Lead-199m2 , style="text-indent:1em" , ^199m2Pb , , colspan="3" style="text-indent:2em" , 2563.8(27) keV , 10.1(2) μs , IT , ¹⁹⁹Pb , (29/2−) , , , -id=Lead-200 , ²⁰⁰Pb , , style="text-align:right" , 82 , style="text-align:right" , 118 , 199.971819(11) , 21.5(4) h , EC , ²⁰⁰Tl , 0+ , , , -id=Lead-200m1 , style="text-indent:1em" , ^200m1Pb , , colspan="3" style="text-indent:2em" , 2183.3(11) keV , 456(6) ns , IT , ²⁰⁰Pb , (9−) , , , -id=Lead-200m2 , style="text-indent:1em" , ^200m2Pb , , colspan="3" style="text-indent:2em" , 3005.8(12) keV , 198(3) ns , IT , ²⁰⁰Pb , 12+) , , , -id=Lead-201 , ²⁰¹Pb , , style="text-align:right" , 82 , style="text-align:right" , 119 , 200.972870(15) , 9.33(3) h , β⁺ , ²⁰¹Tl , 5/2− , , , -id=Lead-201m1 , rowspan=2 style="text-indent:1em" , ^201m1Pb , rowspan=2, , rowspan=2 colspan="3" style="text-indent:2em" , 629.1(3) keV , rowspan=2, 60.8(18) s , IT , ²⁰¹Pb , rowspan=2, 13/2+ , rowspan=2, , rowspan=2, , - , β⁺? , ²⁰¹Tl , -id=Lead-201m2 , style="text-indent:1em" , ^201m2Pb , , colspan="3" style="text-indent:2em" , 2953(20) keV , 508(3) ns , IT , ²⁰¹Pb , (29/2−) , , , -id=Lead-202 , ²⁰²Pb , , style="text-align:right" , 82 , style="text-align:right" , 120 , 201.9721516(41) , 5.25(28)×10⁴ y , EC , ²⁰²Tl , 0+ , , , -id=Lead-202m1 , rowspan=2 style="text-indent:1em" , ^202m1Pb , rowspan=2, , rowspan=2 colspan="3" style="text-indent:2em" , 2169.85(8) keV , rowspan=2, 3.54(2) h , IT (90.5%) , ²⁰²Pb , rowspan=2, 9− , rowspan=2, , rowspan=2, , - , β⁺ (9.5%) , ²⁰²Tl , -id=Lead-202m2 , style="text-indent:1em" , ^202m2Pb , , colspan="3" style="text-indent:2em" , 4140(50)# keV , 100(3) ns , IT , ²⁰²Pb , 16+ , , , -id=Lead-202m3 , style="text-indent:1em" , ^202m3Pb , , colspan="3" style="text-indent:2em" , 5300(50)# keV , 108(3) ns , IT , ²⁰²Pb , 19− , , , -id=Lead-203 , ²⁰³Pb , , style="text-align:right" , 82 , style="text-align:right" , 121 , 202.9733906(70) , 51.924(15) h , EC , ²⁰³Tl , 5/2− , , , -id=Lead-203m1 , style="text-indent:1em" , ^203m1Pb , , colspan="3" style="text-indent:2em" , 825.2(3) keV , 6.21(8) s , IT , ²⁰³Pb , 13/2+ , , , -id=Lead-203m2 , style="text-indent:1em" , ^203m2Pb , , colspan="3" style="text-indent:2em" , 2949.2(4) keV , 480(7) ms , IT , ²⁰³Pb , 29/2− , , , -id=Lead-203m3 , style="text-indent:1em" , ^203m3Pb , , colspan="3" style="text-indent:2em" , 2970(50)# keV , 122(4) ns , IT , ²⁰³Pb , 25/2−# , , , -id=Lead-204 , ²⁰⁴PbUsed in lead–lead dating , , style="text-align:right" , 82 , style="text-align:right" , 122 , 203.9730435(12) , colspan="3" style="text-align:center;",

Observationally stable Stable nuclides are isotopes of a chemical element whose nucleons are in a configuration that does not permit them the surplus energy required to produce a radioactive emission. The nuclei of such isotopes are not radioactive and unlike radionuc ...

, 0+ , 0.014(6) , 0.0000–0.0158 , -id=Lead-204m1 , style="text-indent:1em" , ^204m1Pb , , colspan="3" style="text-indent:2em" , 1274.13(5) keV , 265(6) ns , IT , ²⁰⁴Pb , 4+ , , , -id=Lead-204m2 , style="text-indent:1em" , ^204m2Pb , , colspan="3" style="text-indent:2em" , 2185.88(8) keV , 66.93(10) min , IT , ²⁰⁴Pb , 9− , , , -id=Lead-204m3 , style="text-indent:1em" , ^204m3Pb , , colspan="3" style="text-indent:2em" , 2264.42(6) keV , 490(70) ns , IT , ²⁰⁴Pb , 7− , , , -id=Lead-205 , ²⁰⁵Pb , , style="text-align:right" , 82 , style="text-align:right" , 123 , 204.9744817(12) , 1.70(9)×10⁷ y , EC , ²⁰⁵Tl , 5/2− , , , -id=Lead-205m1 , style="text-indent:1em" , ^205m1Pb , , colspan="3" style="text-indent:2em" , 2.329(7) keV , 24.2(4) μs , IT , ²⁰⁵Pb , 1/2− , , , -id=Lead-205m2 , style="text-indent:1em" , ^205m2Pb , , colspan="3" style="text-indent:2em" , 1013.85(3) keV , 5.55(2) ms , IT , ²⁰⁵Pb , 13/2+ , , , -id=Lead-205m3 , style="text-indent:1em" , ^205m3Pb , , colspan="3" style="text-indent:2em" , 3195.8(6) keV , 217(5) ns , IT , ²⁰⁵Pb , 25/2− , , , - , ²⁰⁶PbFinal

decay product In nuclear physics, a decay product (also known as a daughter product, daughter isotope, radio-daughter, or daughter nuclide) is the remaining nuclide left over from radioactive decay. Radioactive decay often proceeds via a sequence of steps ( d ...

of 4n+2

(the Radium or Uranium series) , Radium G , style="text-align:right" , 82 , style="text-align:right" , 124 , 205.9744652(12) , colspan="3" style="text-align:center;", Observationally stable , 0+ , 0.241(30) , 0.0190–0.8673 , -id=Lead-206m1 , style="text-indent:1em" , ^206m1Pb , , colspan="3" style="text-indent:2em" , 2200.16(4) keV , 125(2) μs , IT , ²⁰⁶Pb , 7− , , , -id=Lead-206m2 , style="text-indent:1em" , ^206m2Pb , , colspan="3" style="text-indent:2em" , 4027.3(7) keV , 202(3) ns , IT , ²⁰⁶Pb , 12+ , , , - , ²⁰⁷PbFinal decay product of 4n+3 decay chain (the

Actinium series In nuclear science a decay chain refers to the predictable series of radioactive disintegrations undergone by the nuclei of certain unstable chemical elements. Radioactive isotopes do not usually decay directly to stable isotopes, but rather ...

) , Actinium D , style="text-align:right" , 82 , style="text-align:right" , 125 , 206.9758968(12) , colspan="3" style="text-align:center;", Observationally stable , 1/2− , 0.221(50) , 0.0035–0.2351 , -id=Lead-207m , style="text-indent:1em" , ^207mPb , , colspan="3" style="text-indent:2em" , 1633.356(4) keV , 806(5) ms , IT , ²⁰⁷Pb , 13/2+ , , , -id=Lead-208 , ²⁰⁸PbHeaviest observationally stable nuclide; final decay product of 4n decay chain (the

Thorium series In nuclear science a decay chain refers to the predictable series of radioactive disintegrations undergone by the nuclei of certain unstable chemical elements. Radioactive isotopes do not usually decay directly to stable isotopes, but rather ...

) , Thorium D , style="text-align:right" , 82 , style="text-align:right" , 126 , 207.9766520(12) , colspan="3" style="text-align:center;", Observationally stable , 0+ , 0.524(70) , 0.0338–0.9775 , -id=Lead-208m , style="text-indent:1em" , ^208mPb , , colspan="3" style="text-indent:2em" , 4895.23(5) keV , 535(35) ns , IT , ²⁰⁸Pb , 10+ , , , -id=Lead-209 , ²⁰⁹Pb , , style="text-align:right" , 82 , style="text-align:right" , 127 , 208.9810900(19) , 3.235(5) h , β⁻ , ''²⁰⁹Bi'' , 9/2+ , TraceIntermediate decay product of ²³⁷Np , , -id=Lead-210 , rowspan=2, ²¹⁰Pb , rowspan=2, Radium D
Radiolead
Radio-lead , rowspan=2 style="text-align:right" , 82 , rowspan=2 style="text-align:right" , 128 , rowspan=2, 209.9841884(16) , rowspan=2, 22.20(22) y , β⁻ (100%) , ²¹⁰Bi , rowspan=2, 0+ , rowspan=2, TraceIntermediate

of ²³⁸U , rowspan=2, , - , α (1.9×10⁻⁶%) , ²⁰⁶Hg , -id=Lead-210m1 , style="text-indent:1em" , ^210m1Pb , , colspan="3" style="text-indent:2em" , 1194.61(18) keV , 92(10) ns , IT , ²¹⁰Pb , 6+ , , , -id=Lead-210m2 , style="text-indent:1em" , ^210m2Pb , , colspan="3" style="text-indent:2em" , 1274.8(3) keV , 201(17) ns , IT , ²¹⁰Pb , 8+ , , , -id=Lead-211 , ²¹¹Pb , Actinium B , style="text-align:right" , 82 , style="text-align:right" , 129 , 210.9887353(24) , 36.1628(25) min , β⁻ , ²¹¹Bi , 9/2+ , TraceIntermediate

of ²³⁵U , , -id=Lead-211m , style="text-indent:1em" , ^211mPb , , colspan="3" style="text-indent:2em" , 1719(23) keV , 159(28) ns , IT , ²¹¹Pb , (27/2+) , , , - , ²¹²Pb , Thorium B , style="text-align:right" , 82 , style="text-align:right" , 130 , 211.9918959(20) , 10.627(6) h , β⁻ , ²¹²Bi , 0+ , TraceIntermediate

of ²³²Th , , -id=Lead-212m , style="text-indent:1em" , ^212mPb , , colspan="3" style="text-indent:2em" , 1335(2) keV , 6.0(8) μs , IT , ²¹²Pb , 8+# , , , -id=Lead-213 , ²¹³Pb , , style="text-align:right" , 82 , style="text-align:right" , 131 , 212.9965608(75) , 10.2(3) min , β⁻ , ²¹³Bi , (9/2+) , Trace , , -id=Lead-213m , style="text-indent:1em" , ^213mPb , , colspan="3" style="text-indent:2em" , 1331.0(17) keV , 260(20) ns , IT , ²¹³Pb , (21/2+) , , , -id=Lead-214 , ²¹⁴Pb , Radium B , style="text-align:right" , 82 , style="text-align:right" , 132 , 213.9998035(21) , 27.06(7) min , β⁻ , ²¹⁴Bi , 0+ , Trace , , -id=Lead-214m , style="text-indent:1em" , ^214mPb , , colspan="3" style="text-indent:2em" , 1420(20) keV , 6.2(3) μs , IT , ²¹⁴Pb , 8+# , , , -id=Lead-215 , ²¹⁵Pb , , style="text-align:right" , 82 , style="text-align:right" , 133 , 215.004662(57) , 142(11) s , β⁻ , ²¹⁵Bi , 9/2+# , , , -id=Lead-216 , ²¹⁶Pb , , style="text-align:right" , 82 , style="text-align:right" , 134 , 216.00806(22)# , 1.66(20) min , β⁻ , ²¹⁶Bi , 0+ , , , -id=Lead-216m , style="text-indent:1em" , ^216mPb , , colspan="3" style="text-indent:2em" , 1514(20) keV , 400(40) ns , IT , ²¹⁶Pb , 8+# , , , -id=Lead-217 , ²¹⁷Pb , , style="text-align:right" , 82 , style="text-align:right" , 135 , 217.01316(32)# , 19.9(53) s , β⁻ , ²¹⁷Bi , 9/2+# , , , -id=Lead-218 , ²¹⁸Pb , , style="text-align:right" , 82 , style="text-align:right" , 136 , 218.01678(32)# , 14.8(68) s , β⁻ , ²¹⁸Bi , 0+ , , , -id=Lead-219 , ²¹⁹Pb , , style="text-align:right" , 82 , style="text-align:right" , 137 , 219.02214(43)# , 3# s
300 ns, β⁻? , ²¹⁹Bi , 11/2+# , , , -id=Lead-220 , ²²⁰Pb , , style="text-align:right" , 82 , style="text-align:right" , 138 , 220.02591(43)# , 1# s
300 ns, β⁻? , ²²⁰Bi , 0+ , ,

Lead-206

²⁰⁶Pb is the final step in the decay chain of ²³⁸U, the "radium series" or "uranium series". In a closed system, over time, a given mass of ²³⁸U will decay in a sequence of steps culminating in ²⁰⁶Pb. The production of intermediate products eventually reaches an equilibrium (though this takes a long time, as the half-life of ²³⁴U is 245,500 years). Once this stabilized system is reached, the ratio of ²³⁸U to ²⁰⁶Pb will steadily decrease, while the ratios of the other intermediate products to each other remain constant. Like most radioisotopes found in the radium series, ²⁰⁶Pb was initially named as a variation of radium, specifically radium G. It is the decay product of both ²¹⁰Po (historically called radium F) by

, and the much rarer ²⁰⁶Tl (radium E^II) by

. Lead-206 has been proposed for use in fast breeder nuclear fission reactor coolant over the use of natural lead mixture (which also includes other stable lead isotopes) as a mechanism to improve neutron economy and greatly suppress unwanted production of highly radioactive byproducts.

Lead-204, -207, and -208

²⁰⁴Pb is entirely primordial, and is thus useful for estimating the fraction of the other lead isotopes in a given sample that are also primordial, since the relative fractions of the various primordial lead isotopes is constant everywhere. Any excess lead-206, -207, and -208 is thus assumed to be

radiogenic A radiogenic nuclide is a nuclide that is produced by a process of radioactive decay. It may itself be radioactive (a radionuclide) or stable (a stable nuclide). Radiogenic nuclides (more commonly referred to as radiogenic isotopes) form some of ...

in origin, allowing various uranium and thorium dating schemes to be used to estimate the age of rocks (time since their formation) based on the relative abundance of lead-204 to other isotopes. ²⁰⁷Pb is the end of the

from ²³⁵U. ²⁰⁸Pb is the end of the

from ²³²Th. While it only makes up approximately half of the composition of lead in most places on Earth, it can be found naturally enriched up to around 90% in thorium ores. ²⁰⁸Pb is the heaviest known stable nuclide and also the heaviest known doubly magic nucleus, as ''Z'' = 82 and ''N'' = 126 correspond to closed nuclear shells. As a consequence of this particularly stable configuration, its neutron capture cross section is very low (even lower than that of

deuterium Deuterium (hydrogen-2, symbol H or D, also known as heavy hydrogen) is one of two stable isotopes of hydrogen; the other is protium, or hydrogen-1, H. The deuterium nucleus (deuteron) contains one proton and one neutron, whereas the far more c ...

in the thermal spectrum), making it of interest for

lead-cooled fast reactor The lead-cooled fast reactor is a nuclear reactor design that uses molten lead or lead-bismuth eutectic as its coolant. These materials can be used as the primary coolant because they have low neutron absorption and relatively low melting poi ...

s. In 2025 a published study suggested that the nucleus of ²⁰⁸Pb is not perfectly spherical as previously believed.

Lead-212

Lead-212 is a radioactive isotope of lead that has gained significant attention in nuclear medicine, particularly in targeted alpha therapy (TAT). This isotope is part of the

of primordial

thorium-232 Thorium-232 () is the main naturally occurring isotope of thorium, with a relative abundance of 99.98%. It has a half life of 14.05 billion years, which makes it the longest-lived isotope of thorium. It decays by alpha decay to radium-228; its de ...

. Lead-212 is characterized by its unstable nuclear configuration and undergoes radioactive decay through beta emission to form bismuth-212, which further decays to emit alpha particles. This decay chain is an in vivo generator system of alpha particles that can be utilized for therapeutic purposes, particularly targeted alpha therapy, by delivering potent, localized radiation to cancer cells.

References

Sources