Review of the analysis of 234 Th in small volume (2-4 L) seawater samples: improvements and recommendations.

The short-lived radionuclide ²³⁴ Th is widely used to study particle scavenging and transport from the upper ocean to deeper waters. This manuscript optimizes, reviews and validates the collection, processing and analyses of total ²³⁴ Th in seawater and suggests areas of further improvements. The standard ²³⁴ Th protocol method consists of scavenging ²³⁴ Th from seawater via a MnO ₂ precipitate, beta counting, and using chemical recoveries determined by adding ²³⁰ Th. The revised protocol decreases sample volumes to 2 L, shortens wait times between steps, and simplifies the chemical recovery process, expanding the ability to more rapidly and safely apply the ²³⁴ Th method.
Competing Interests: Conflict of interestThe authors have no relevant financial or non-financial interests to disclose.
(© The Author(s) 2021.)