TY - JOUR
T1 - Decline of anthropogenic lead in South Atlantic Ocean surface waters from 1990 to 2011
T2 - New constraints from concentration and isotope data
AU - Olivelli, Arianna
AU - Murphy, Katy
AU - Bridgestock, Luke
AU - Wilson, David J.
AU - Rijkenberg, Micha
AU - Middag, Rob
AU - Weiss, Dominik J.
AU - van de Flierdt, Tina
AU - Rehkämper, Mark
N1 - Publisher Copyright:
© 2023 The Author(s)
PY - 2023/4
Y1 - 2023/4
N2 - Anthropogenic emissions have severely perturbed the marine biogeochemical cycle of lead (Pb). Here, we present new Pb concentration and isotope data for surface seawater from GEOTRACES section GA02, sampled in the western South Atlantic in 2011. The South Atlantic is divided into three hydrographic zones: equatorial (0–20°S), subtropical (20–40°S), and subantarctic (40–60°S). The equatorial zone is dominated by previously deposited Pb transported by surface currents. The subtropical zone largely reflects anthropogenic Pb emissions from South America, whilst the subantarctic zone presents a mixture of South American anthropogenic Pb and natural Pb from Patagonian dust. The mean Pb concentration of 16.7 ± 3.8 pmol/kg is 34 % lower than in the 1990s, mostly driven by changes in the subtropical zone, with the fraction of natural Pb increasing from 24 % to 36 % between 1996 and 2011. Although anthropogenic Pb remains predominant, these findings demonstrate the effectiveness of policies that banned leaded gasoline.
AB - Anthropogenic emissions have severely perturbed the marine biogeochemical cycle of lead (Pb). Here, we present new Pb concentration and isotope data for surface seawater from GEOTRACES section GA02, sampled in the western South Atlantic in 2011. The South Atlantic is divided into three hydrographic zones: equatorial (0–20°S), subtropical (20–40°S), and subantarctic (40–60°S). The equatorial zone is dominated by previously deposited Pb transported by surface currents. The subtropical zone largely reflects anthropogenic Pb emissions from South America, whilst the subantarctic zone presents a mixture of South American anthropogenic Pb and natural Pb from Patagonian dust. The mean Pb concentration of 16.7 ± 3.8 pmol/kg is 34 % lower than in the 1990s, mostly driven by changes in the subtropical zone, with the fraction of natural Pb increasing from 24 % to 36 % between 1996 and 2011. Although anthropogenic Pb remains predominant, these findings demonstrate the effectiveness of policies that banned leaded gasoline.
KW - GEOTRACES
KW - Isotopic composition
KW - Lead
KW - Pollution
KW - Seawater
UR - http://www.scopus.com/inward/record.url?scp=85149960283&partnerID=8YFLogxK
U2 - 10.1016/j.marpolbul.2023.114798
DO - 10.1016/j.marpolbul.2023.114798
M3 - Article
C2 - 36907166
AN - SCOPUS:85149960283
SN - 0025-326X
VL - 189
JO - Marine Pollution Bulletin
JF - Marine Pollution Bulletin
M1 - 114798
ER -