A 1951–1998 Lutao coral Pb isotope record reveals site-specific, marine-integrated anthropogenic Pb pollution signals in the Northwest Pacific

Coral lead (Pb) isotope records provide multi-decadal perspectives on marine Pb histories, but how individual records represent regional isotope histories remains an important interpretive question. We present a 1951–1998 Pb isotope record from a Porites coral at Lutao, southeast of Taiwan, and compare it with published records from Dongsha and Ogasawara in the Northwest Pacific. The three coral records exhibited substantial inter-site isotopic differences during 1953–1963, smaller differences in interval-mean 208 Pb/ 207 Pb during 1964–1984, and persistent site-specific characteristics. In 1985–1998, Lutao had a statistically distinguishable lower 208 Pb/ 207 Pb composition than Dongsha, whereas the middle-to-late change within Lutao itself was not statistically resolved. This contrast shows that inter-site isotopic differences need not imply an equivalent temporal shift at an individual site. Published Pb isotope reference fields are compatible with multiple possible source combinations but do not uniquely identify historical sources or marine transport mechanisms. Together, these results reveal spatial heterogeneity in coral Pb isotope histories, with smaller inter-site differences during 1964–1984, and highlight the need to evaluate the spatial representativeness of individual coral Pb isotope records before extrapolating site-specific signatures to regional historical interpretations.