Insights about levels and sources of organic pollution in an urbanized Amazon estuary (Belém, PA, Northern Brazil).

Amazon aquatic systems have been affected by organic pollution from urbanized regions. This study was conducted to determine the levels, sources, and distribution patterns of 16 polycyclic aromatic hydrocarbons (PAHs) and 6 steroid markers in surficial sediments from an important urbanized Amazon estuarine system (Belém, PA, Northern Brazil). Total PAH concentration (∑PAH) ranged from 878.

Assessment of polycyclic aromatic hydrocarbons in three environmental components from a tropical estuary in Northeast Brazil.

The evaluation of occurrence, risk quotient (RQ), bioaccumulation factor (BAF), and sources of PAH was conducted in Sergipe-Poxim estuarine system. PAH distribution that ranged from 7.1 to 30.

The impact of anthropogenic activity at the tropical Sergipe-Poxim estuarine system, Northeast Brazil: Fecal indicators.

The individual concentrations and sources of sterols in sediments samples collected in two periods 2017 (dry period /March and rainy period/August) were determined along with the Sergipe-Poxim estuarine system, Aracaju, Brazil. The individual sterols concentration ranged from 135 to 21,746 ng g (March) and 191 to 144,748 ng g (August) and the distribution was mainly dominated by β-sitosterol in both periods with 37.2% (March) and 70.

Polycyclic aromatic hydrocarbons in sediments of the Amazon River Estuary (Amapá, Northern Brazil): Distribution, sources and potential ecological risk.

The distribution, sources and potential ecological risk of priority polycyclic aromatic hydrocarbons (PAHs) in sediment from the Amazon River Estuary (Macapá and Santana, Amapá, Northern Brazil) were investigated. The total PAHs concentration (∑PAH) ranged from 22.2 to 158.

PAH Baselines for Amazonic Surficial Sediments: A Case of Study in Guajará Bay and Guamá River (Northern Brazil).

The 16 priority PAH were determined in sediment samples from the insular zone of Guajará Bay and Guamá River (Southern Amazon River mouth). Low hydrocarbon levels were observed and naphthalene was the most representative PAH. The low molecular weight PAH represented 51% of the total PAH.

Concentration, distribution and source apportionment of polycyclic aromatic hydrocarbons (PAH) in Poxim River sediments, Brazil.

The individual concentrations, total amount and sources of 16 priority polycyclic aromatic hydrocarbons (PAH) in sediments collected along of the Poxim River, Aracaju, Brazil, were for the first time determined. The ΣPAH ranged between 2.2±1.

Evaluation of anthropogenic contamination using sterol markers in a tropical estuarine system of northeast Brazil.

The São Francisco River estuarine system, located in the Northeast coast of Brazil, has great economic, tourist and social importance. Its waters are used for activities such as agriculture, aquaculture, navigation and fishery, which supplies the surrounding communities. In this study, sterols markers were determined in twenty-eight sediment samples from São Francisco River estuary by gas chromatography - mass spectrometry (GC-MS).

Seasonal distribution of aliphatic hydrocarbons in the Vaza Barris Estuarine System, Sergipe, Brazil.

The seasonal assessment of anthropogenic activities in the Vaza Barris estuarine river system, located in the Sergipe state, northeastern Brazil, was performed using the aliphatic hydrocarbon distribution. The aliphatic hydrocarbon and isoprenoid (Pristane and Phytane) concentrations ranged between 0.19 μg g(-1) and 8.