Disequilibrium between ²¹⁰Pb (t½: 22.3 years) and its granddaughter ²¹⁰Po (t½: 138.4 days) has been used to infer organic particle removal rates from the surface ocean on a timescale of weeks to months; however, the behavior of the short-lived intermediary daughter ²¹⁰Bi (t½: 5.01 days) is not well known. Here, timeseries measurements of ²¹⁰Pb, ²¹⁰Bi, and ²¹⁰Po in the Milwaukee Inner Harbor on Lake Michigan showed respective particle distribution (K_d) coefficients of 7.1 (± 0.4) × 10⁵, 9.3 (± 1.7) × 10⁵, and 10.2 (± 0.6) × 10⁵ L kg ⁻¹, giving K_d ratios, or fractionation factors (F), of F_Bi/Pb = 1.3 ± 0.3, F_Po/Bi = 1.1 ± 0.2, and F_Po/Pb of 1.4 ± 0.1. After a large rain event, total ²¹⁰Pb, ²¹⁰Bi, and ²¹⁰Po activities in the harbor water column decreased over a course of 12 days from 347 to 105 dpm ²¹⁰Pb m⁻³, 397 to 88 dpm ²¹⁰Bi m⁻³, and 144 to 58 dpm ²¹⁰Po m⁻³. This is the first observation of a total ²¹⁰Bi/²¹⁰Po activity ratio of <1 in an aquatic system. A 1-D non-steady-state model of nuclide fluxes suggested that 92% of the reduction in ²¹⁰Bi activity was due to removal from the water column, with the remainder accounted for by net in situ decay. The potential for using ²¹⁰Bi as a tracer of high and variable particle scavenging rates in lakes and shallow marine systems is supported.

²¹⁰ Pb（t½：22.3 年）与其孙女²¹⁰ Po（t½：138.4 天）之间的不平衡已被用于推断在数周到数月的时间尺度内从表层海洋中去除有机颗粒的速率；然而，短命的中介女儿²¹⁰ Bi（t½：5.01天）的行为并不为人所知。在这里，密歇根湖密尔沃基内港的²¹⁰ Pb、²¹⁰ Bi 和²¹⁰ Po 的时间序列测量显示各自的粒子分布 ( K _d ) 系数为 7.1 (± 0.4) × 10 ⁵、9.3 (± 1.7) × 10 ⁵，和 10.2 (± 0.6) × 10 ⁵  L kg ^-1，给出F _Bi/Pb  = 1.3 ± 0.3、F _Po/Bi  = 1.1 ± 0.2 和F _Po/Pb 1.4 ± 0.1 的K _d比率或分馏因子 ( F ) 。在一场大雨事件之后，港口水体中的²¹⁰ Pb、²¹⁰ Bi 和²¹⁰ Po 的总活性在 12 天的过程中从 347 到 105 dpm ²¹⁰ Pb m ^-3、397 到 88 dpm ²¹⁰ Bi m ^-3，和 144 至 58 dpm ²¹⁰ Po m ^-3。这是第一次观测到总共²¹⁰ Bi/ ²¹⁰水生系统中的 Po 活性比 <1。核素通量的一维非稳态模型表明²¹⁰ Bi 活性降低的 92%是由于从水柱中去除，其余部分由净原位衰减引起。支持使用²¹⁰ Bi 作为湖泊和浅海系统中高和可变颗粒清除率的示踪剂的潜力。