Lead-210 and Beryllium-7 fallout rates on the southeastern coast of Brazil

• Published in: Journal of environmental radioactivity Vol. 102; no. 12; pp. 1122 - 1125
• Main Authors: Sanders, Christian J., Smoak, Joseph M., Cable, Peter H., Patchineelam, Sambasiva R., Sanders, Luciana M.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.12.2011; Elsevier
• Subjects: 210Pb; 210Pb sediment inventories; 7Be; Air masses; Air Movements; Applied sciences; Atmosphere - chemistry; Atmospheric; Atmospherics; Beryllium - analysis; Beryllium - chemistry; Brazil; Deposition; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Exact sciences and technology; Fallout; Flux; Geologic Sediments - chemistry; Lead Radioisotopes - analysis; Lead Radioisotopes - chemistry; Pollution; Pollution sources. Measurement results; Pollution, environment geology; Radiation Monitoring; Radioactive Fallout - analysis; Radioactivity; Radioisotopes - analysis; Radioisotopes - chemistry; Sedimentation; Soil and sediments pollution; Wind mass; South America; Brazil; America; ASW, Brazil, Rio de Janeiro, Niteroi; Wind mass; 7Be; 210Pb; 210Pb sediment inventories; Atmospheric; Natural origin pollution; Atmospheric condition; Radioactive pollution; Pb sediment inventories; Atmospheric fallout; Be; Lead 210; Cosmogenic factor; Radioisotope; Beryllium 7; Sediments; Radioactive fall out; Coastal zone; Pb
• ISSN: 0265-931X; 1879-1700
• DOI: 10.1016/j.jenvrad.2011.07.008

Total 210Pb and 7Be fallout rates were measured on the coastal region of Niteroi, Brazil. The monthly depositional flux of 210Pb and 7Be varied by a factor of 26, from 1.7 to 43.3 mBq cm −2 year −1 and ∼27, from 7.5 to 203.5 mBq cm −2 year −1, respectively. The relatively large oscillations in the depositional flux of 210Pb at this study site were likely due to variations in air mass sources, while the 7Be fluctuations may be driven by a combination of weather conditions. Local geology could support the periodic high fluxes of 210Pb from continental air masses, as shifting oceanic wind sources were affirmed by the uncorrelated 210Pb and 7Be fallout activities and 7Be/ 210Pb ratios. The 210Pb atmospheric deposition was found to be in agreement with local sediment inventories, an important consideration in geochemical studies that estimate sedimentation processes. ► Fallout rates of 210Pb and 7Be indicate depositional flux during a 12-month period. ► Oscillations in 210Pb and 7Be fallout are driven by geology ( 210Pb) and weather. ► Regional trends in 7Be and 210Pb fluxes used in geochemical processes.