Geochemical background indicators within a tropical estuarine system influenced by a port-industrial complex.

This study aims to determine the background values for metals in the Suape estuarine system, Brazil, and to identify contamination caused by anthropogenic sources. Two cores were sampled. Sedimentation rates and metal content were analysed. The Al-normalized method was used to infer the background values, and to identify anthropic influences, the enrichment and contamination factors and the geoaccumulation index were employed. The results revealed an Mn, Ni, Zn, Ga, Pb, Sr, Ti, Mg, V and Fe content (mg kg-1) of 101.8, 5.7, 24.4, 8.3, 14.5, 41.9, 2744.6, 4581, 14.9 and ~ 1% respectively. After the installation of the Suape port, an increase in metal contents and in fluxes were recorded. Increases in Zn, Ga, V and Pb are supported by the indexes showing moderate contamination, enrichment and suggest an area moderately polluted. The other studied metals do not reflect an anthropogenic impact, with low values of contamination, enrichment factors and geoaccumulation indexes.

Origanum majorana Essential Oil Lacks Mutagenic Activity in the Salmonella/Microsome and Micronucleus Assays.

The present study aimed to investigate the in vitro mutagenic activity of Origanum majorana essential oil. The most abundant compounds identified by GC-MS were γ-terpinene (25.73%), α-terpinene (17.35%), terpinen-4-ol (17.24%), and sabinene (10.8%). Mutagenicity was evaluated by the Salmonella/microsome test using the preincubation procedure on TA98, TA97a, TA100, TA102, and TA1535 Salmonella typhimurium strains, in the absence or in the presence of metabolic activation. Cytotoxicity was detected at concentrations higher than 0.04 µL/plate in the absence of S9 mix and higher than 0.08 µL/plate in the presence of S9 mix and no gene mutation increase was observed. For the in vitro mammalian cell micronucleus test, V79 Chinese hamster lung fibroblasts were used. Cytotoxicity was only observed at concentrations higher than or equal to 0.05 µg/mL. Moreover, when tested in noncytotoxic concentrations, O. majorana essential oil was not able to induce chromosome mutation. The results from this study therefore suggest that O. majorana essential oil is not mutagenic at the concentrations tested in the Salmonella/microsome and micronucleus assays.