Metal-specific biomagnification and trophic dilution in the coastal foodweb of the California sea lion (Zalophus californianus) off Bahía Magdalena, Mexico: The role of the benthic-pelagic foodweb in the trophic transfer of trace and toxic metals.

Trace metals concentrations along with stable isotopes ratios were measured in marine algae, sea grass, sponges, echinoderms, mollusks, crustaceans, fishes, and the California sea lion, to assess the bioaccumulation potential and detect potential risks for top predators off Bahia Magdalena, Mexico. We assessed the trophic magnification factor (TMF) to determine the potential for biomagnification of 11 trace metals. The concentrations of Fe and Zn were one order of magnitude higher than all other metals.

Inferring pollution records in sediment cores from transitional environments of Marquelia coast, Guerrero, Mexico.

The vertical distribution pattern and concentrations of elements (Fe, Al, Ca, Mg, Mn, Cr, Cu, Ni, Co, Pb, Zn, and As) in the estuarine and lagoon region of Marquelia coast, Guerrero, Mexico, were studied to comprehend the origin and pollutant phases of geochemical elements. Henceforth, two sediment core samples [C1 (127 cm) and C2 (110 cm)] were collected to assess the pollution status using geochemical indices, namely anthropogenic factor (AF), enrichment factor (EF), and geoaccumulation index (I). Additionally, the elemental concentrations were compared with the sediment quality guidelines (SQGs) to examine the potential risks to biota.

Comprehensive study on metal contents and their ecological risks in beach sediments of KwaZulu-Natal province, South Africa.

Sediment metal concentrations were assessed in five different beach regions (n = 183) of KwaZulu-Natal (KZN) province in South Africa. Metal distribution revealed that Cr, Cu, Mo, Cd, Zn, Hg and As exceed the background upper continental crust values suggesting their anthropogenic origin (mining, agricultural and industrial) apart from natural geological inputs (gold placer deposits and heavy minerals). Various geochemical indices (Geoaccumulation index, Enrichment factor and Degree of contamination) confirmed that the sediment samples are extremely contaminated with Cr, Cd and Hg.

Trace elements in marine organisms of Magdalena Bay, Pacific Coast of Mexico: Bioaccumulation in a pristine environment.

Trace element (Fe, Mn, Cr, Cu, Ni, Co, Pb, Zn, Cd, As, Hg) concentrations were assessed in marine organisms (n = 52) sampled from the Magdalena Bay lagoon complex in Baja California Sur, Mexico, a pristine marine environment. The overall trend of metal concentrations (dry weight) in the organisms was found to be Fe > Zn > Cd > Cu > Mn > Pb > As > Hg > Ni > Cr > Co. Bivalve mollusks (53.

Heavy metal concentrations in diploid and triploid oysters (Crassostrea gigas) from three farms on the north-central coast of Sinaloa, Mexico.

The concentrations of Cu, Cd, Pb, Zn, and Hg in diploid and triploid oysters from three farms (Guasave, Ahome, and Navolato) on the north-central coast of Sinaloa, Mexico, were assessed based on samples recovered during a single culture cycle 2013-2014. Metal burdens were more strongly correlated (p < 0.05) with the location of the farm than with either the ploidy or the interaction of both variables.

Bioaccumulation of trace metals in farmed pacific oysters Crassostrea gigas from SW Gulf of California coast, Mexico.

The aim of the study was to evaluate the bioavailability of trace metals (Chromium, Copper, Nickel, Lead, Zinc, Cadmium, Arsenic, and Mercury) in the commercially consumed Crassostrea gigas oysters collected over a 12-month growth period (2011-12) from an experimental cultivation farm in La Pitahaya, Sinaloa State, Mexico. Sediment and water samples were also collected from four different zones adjacent to the cultivation area to identify the concentration patterns of metals. The results revealed that sewage disposals, fertilizers used for agricultural practices and shrimp culture are the major sources for the enrichment of certain toxic metals.

Metal concentration in the tourist beaches of South Durban: An industrial hub of South Africa.

South Durban basin of South Africa has witnessed tremendous urban, industrial expansion and mass tourism impacts exerting significant pressure over marine environments. 43 sediment samples from 7 different beaches (Bluff beach; Ansteys beach; Brighton beach; Cutting beach; Isipingo beach; Tiger Rocks beach; Amanzimtoti beach) were analyzed for acid leachable metals (ALMs) Fe, Mg, Mn, Cr, Cu, Mo, Ni, Co, Pb, Cd, Zn and Hg. The metal concentrations found in all the beaches were higher than the background reference values (avg.

Metal enrichment of soils following the April 2012-2013 eruptive activity of the Popocatépetl volcano, Puebla, Mexico.

We analyzed the total (Zn, Pb, Ni, Hg, Cr, Cd, Cu, As) and partially leachable metals (PLMs) in 25 ash and soil samples from recent (2012-2013) eruptions of the Popocatépetl Volcano in Central Mexico. More recent ash and soil samples from volcanic activity in 2012-2013 had higher metal concentrations than older samples from eruptions in 1997 suggesting that the naturally highly volatile and mobile metals leach into nearby fresh water sources. The higher proportions of As (74.

Metal concentrations in demersal fish species from Santa Maria Bay, Baja California Sur, Mexico (Pacific coast).

Concentrations of 11 trace metals (Fe, Mn, Cr, Cu, Ni, Co, Pb, Zn, Cd, As, Hg) in 40 fish species from Santa Maria Bay, Baja California Sur, Mexico, the strategically important area for marine mammals and organisms were analyzed. Based on their concentrations the ranking of metals Fe>Zn>Ni>Cr>Mn>Pb>Cu>Co>As>Cd>Hg suggests that organism size, metabolism and feeding habits are correlated with metal concentrations. Local geological formations affect the concentrations of different metals in the aquatic environment and are subsequently transferred to fishes.