Oil spill in the Río de la Plata estuary,Argentina:1.

COLOMBO J.C.; BARREDA A.; BILOS C.; CAPPELLETTI N.; DEMICHELIS S.; LOMBARDI P.; MIGOYA M.C.; SKORUPKA C.; SUÁREZ G.

ENVIRONMENTAL POLLUTION

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2005 vol. 134 p. 277 - 289

0269-7491

Aliphatic (ALI)and aromatic (ARO)hydrocarbon concentrations,composition and sources were evaluated in waters,sediments, soils and biota to assess the impact of w tons of oil spilled in R. ´o de la Plata coastal waters.Total ALI levels ranged from 0.4 .262 m l in waters,0.01 .87 m g in sediments,5 .39 m g in bivalves,12 .323 m g in macrophytes to 948 .5187 m g in soils.ARO varied from non-detected 10 m l,0.01 .1.3 m g,1.0 .16 m g,0.5 .6.9 m g to 22 .67 m g,respectively.O .shore (1,5,15 km)waters and sediments were little a .ected and contained low background hydrocarbon levels re .ecting an e .ective wind-driven transport of the slick to the coast.Six months after the spill,coastal waters,sediments,soils and biota still presented very high levels exceeding baseline concentrations by 1 .3 orders of magnitude.UCM/resolved aliphatic ratio showed a clear trend of increasing decay:coastal waters (3.3)! (6.7)! (9.4)!.shore sediments (13)! sediments (17)! (52).All environmental compartments consistently indicated that the most impacted area was the central sector close to Magdalena city,specially low-energy stream embouchures and bays which acted as e .cient oil traps.The evaluation of hydrocarbon composition by principal component analysis indicated the predominance of biogenic (algae,vascular plant cuticular waxes),background anthropic,pyrogenic and diagenetic ydrocarbons,o .shore and in non-impacted coastal sites.In contrast,polluted stations presented petrogenic signatures characterized by the abundance of isoprenoids,low molecular weight n -alkanes and methylated aromatics in di .erent stages of alteration.The petrogenic/biogenic ratio (!-C22 C n -C15 C -C17 C n -C23)and petrogenic/pyrogenic relationship (methylated/unsubstitued PAH)discriminated the samples according to the di .erent degree of impact.The following paper present the results of the study of the progress of hydrocarbon disappearance in sediments and soils 13 and 42 months after the spill. n -alkanes and methylated aromatics in di .erent stages of alteration.The petrogenic/biogenic ratio (!-C22 C n -C15 C -C17 C n -C23)and petrogenic/pyrogenic relationship (methylated/unsubstitued PAH)discriminated the samples according to the di .erent degree of impact.The following paper present the results of the study of the progress of hydrocarbon disappearance in sediments and soils 13 and 42 months after the spill.