Diagnosis of trace metal contamination in sediments: the example of Ensenada and El Sauzal, two harbors in Baja California, Mexico.
Total metal concentrations in sediments from within Ensenada and El Sauzal Harbors are generally higher than at the mouths. Grain-size analyses suggested that this enrichment could be due to the presence of fine-grained sediments in the inner part of the harbors rather than to anthropogenic perturbations. The (Me/Al)sample ratios for Pb, Co, Ni and Fe were significantly higher for Ensenada Harbor relative to El Sauzal Harbor, whereas the ratios for Cd, Mn, Zn and Cu were statistically equivalent for both harbors. Calculated enrichment factors [EFMe=(Me/Al)sample/(Me/Al)shale] indicated that the metals showing slight enrichment were those associated with anthropogenic contamination (Pb, Zn), or probably related to primary productivity in the water column (Cd, Co). The levels of most of the metals were not greatly enriched, a consideration that is of the utmost importance when contamination issues are at stake.
Huerta-Diaz
Miguel Angel
MA
Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, PMB-133, P.O. Box 189003, Coronado, CA 92178-9003, USA. mhuerta@uabc.mx
Delgadillo-Hinojosa
Francisco
F
Hernández-Ayón
Martín
M
Segovia-Zavala
José Antonio
JA
García-Esquivel
Zaúl
Z
López-Zárate
Héctor
H
Siqueiros-Valencia
Arturo
A
Galindo-Bect
Salvador
S
D002244:Carbon / Q000032:analysis; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000032:analysis*; D019015:Geologic Sediments / Q000737:chemistry*; D019216:Metals, Heavy / Q000032:analysis*; D008800:Mexico; D010316:Particle Size
D004785:Environmental Pollutants; D019216:Metals, Heavy; D002244:Carbon