The usefulness of ecotoxicological approaches to assess environmental impacts caused by oil spills

Accidents involving oil spills have a high potential to cause catastrophic environmental impacts. However, the Brazilian legislation and guidelines to plan and determine response actions in case of oil accidents are vague and generally do not include the assessment of toxic effects of oil on the exposed biota and ecosystems. Therefore, such actions are unable to adequately assess the environmental effects of oil in the short, medium and long terms. Ecotoxicological methods consist of cost-effective and robust alternatives to identify and quantify the effects of oil on the exposed ecosystems. Such approaches should be incorporated into response actions in episodes of oil spills in aquatic environments

Urbanización costera y polución marina

Historicamente, as cidades litorâneas brasileiras foram estabelecidas sem um planejamento adequado, muitas vezes deixando de lado alguns aspectos básicos, como os sistemas de saneamento. Assim, esgotos e águas de drenagem urbanas frequentemente acabam despejados no mar, onde produzem impactos negativos sobre o ambiente, a saúde pública e a economia. A situação ainda é bastante complicada, dado o enorme atraso na adequação das cidades quanto à coleta e à disposição final dos esgotos, e um quadro ainda mais preocupante se refere às drenagens urbanas. É fundamental que seja dada prioridade ao saneamento das cidades costeiras, considerando os objetivos de sustentabilidade previstos na Agenda 2030.Historically, the Brazilian coastal cities have established and grown without proper planning. Some basic aspects were often left aside, such as the sanitation systems. Thus, waste waters and urban stormwater runoff normally end up being released into the sea, where they cause adverse impacts on the environment, public health and economy. This scenario remains quite complicated, as the improvement of the cities’ infrastructure for collecting and treating waste waters is deeply delayed, and a more concerning picture refers to the urban drainage. It is necessary to prioritize the sanitation of Brazilian coastal cities, based on the sustainable development goals proposed in the Agenda 2030.Históricamente, las ciudades costeras brasileñas se establecieron sin una planificación adecuada, frecuentemente dejando de lado algunos aspectos básicos, como los sistemas de saneamiento. Por lo tanto, las aguas residuales y de drenaje urbanas terminan en el mar, en la mayoría de los casos, donde producen impactos negativos sobre el medio ambiente, la salud pública y la economía. La situación sigue siendo bastante complicada, dado el enorme retraso en la adecuación de las ciudades respecto a la recogida y destino final de las aguas residuales, y un panorama aún más preocupante se refiere en al drenaje urbano. Es fundamental que se dé prioridad al saneamiento en las ciudades costeras, considerando los objetivos de sostenibilidad establecidos en la Agenda 2030

Contamination and toxicity in a subtropical Estuarine Protected Area influenced by former mining activities

The present paper reviews information about sources, fate, concentrations and toxicity of the metals found in the Cananéia-Iguape Estuarine Complex (CIEC), which is within a Ramsar site, the Cananéia-Iguape-Peruíbe Environmental Protected Area (CIP-PA). The main sources of metals to CIEC are the former mining sites located upstream, on the Ribeira de Iguape River basin. Pb is reported as the element of primary concern, but Cu, Zn, Cr and As have been detected in sediments and biota. In general, higher levels of metals are associated with muddy sediments, in depositional portions of the estuary. Metals appear to be bioavailable, as sediment toxicity has been reported, together with bioaccumulation and sub-chronic effects in fish and invertebrates. Areas with higher concentrations of metals and more severe sediment toxicity are not necessarily the closest to the sources. The worse conditions occur in depositional sites, which depend on rainfall in catchment basin and hydrological processes in the estuary. In fact, during the flooding season the deposition of particles seems to move southward, carrying metals to the southern portion of the CIEC. The results suggest that the protection objectives are not being fully achieved, demanding actions to ensure control of both internal and external sources of contaminants for the CIEC. Additionally, new enforcements and actions are required to control the contamination sources of mining residues located upstream. The current review highlights that estuarine and marine protected areas may be impacted by contaminants released from distant sources, and this situation should be properly addressed in management plans

Water toxicity assessment of Santos Bay under different climate conditions

Climate conditions and the movement of water masses are among the main factors that influence the destination of pollutants, acting upon transport and dispersion affecting, thus, the quality of water. Samples from Santos Bay were collected under normal conditions (08/21/2008) and during the entrance of a frontal system (08/22/2008) and tested for chronic ecotoxicity using fertilized eggs of sea urchin Lytechinus variegatus. Samples were toxic for stations near Xixová-Japuí State Park, Port of Santos, Submarine Outfall and Moela’s Island, sites related to pollution sources. Differences in climate conditions were observed and its contribution on toxicity seemed to be significant at the entrance of São Vicente estuary and Moela’s Island. At the stations in Santos Bay under influence of contamination from multiple sources such as the presence of outfall and sediments disposal from dredging, the continuous release of compounds still plays an important role in environmental quality

Modeling the dispersion of endocrine disruptors in the Santos Estuarine System (Sao Paulo State, Brazil)

Estrogens are hormones responsible for growth and reproduction. They are naturally synthesized by animals and humans alike. Xenoestrogens are identical to natural hormones, but they are man-made and used as oral contraceptives. Xenoestrogens are a specific group of drugs found in domestic wastewater and some environmental matrices. These compounds remain after conventional sewage treatment and, consequently, affect both the environment and non-target aquatic organisms. In this study, we used the Delft3D hydrodynamic model to estimate the amount of both natural and synthetic estrogens that have been released in the Estuarine System of Santos and São Vicente and the Santos Bay. The data on flow from the sewage treatment plants and on average concentrations of natural and synthetic estrogens released in aquatic environments were obtained from the literature. The results of the modeling showed higher concentrations of estrogens in the estuarine waters of the Largo Pompeba region, the São Vicente Canal, and the Santos Bay, which are regions that receive greater inflows of domestic sewage. The results also suggest that higher concentrations of estrogenic compounds are expected to be found in areas with higher levels of salinity.Estrogênios são hormônios responsáveis pelo crescimento e reprodução, sendo naturalmente sintetizados por animais e seres humanos. Os xenoestrogênios são hormônios idênticos aos naturais, porém fabricados pelo homem e utilizados como contraceptivos orais. Xenoestrogênios formam um grupo específico de fármacos encontrados em efluentes domésticos e em algumas matrizes ambientais. Estes compostos persistem nos tratamentos convencionais de esgotos e, consequentemente, atingem os ambientes e os organismos aquáticos não alvos. Neste trabalho, foi estimada a dispersão de estrogênios naturais e sintéticos quando estes são possivelmente lançados no Sistema Estuarino de Santos e São Vicente e Baía de Santos, utilizando o modelo hidrodinâmico Delft3D. Os dados das vazões de estações de tratamento de esgotos e de concentrações médias de estrogênios naturais e sintéticos lançadas nos ambientes aquáticos foram obtidos da literatura. Os resultados mostraram concentrações mais elevadas de estrogênios nas águas estuarinas da região do Largo da Pompeba, Canal de São Vicente, e na Baía de Santos, sendo estas as regiões que recebem maior aporte de esgotos domésticos. Os resultados da modelagem sugerem ainda que maiores concentrações dos compostos estrogênicos são esperadas nos locais com níveis mais elevados de salinidade

Chronic effects of fire suppressors on the reproduction of the copepod Nitocra sp.

Fire suppressors are widely used in firefighting and their chemical composition may present a mixture of perfluorochlorinated surfactants (PFCs), including the perfluorooctane sulfonate (PFOS) which has been internationally banned due to its classification as a persistent organic pollutant (POP). PFCs have been found in environmental matrices and soft tissues of organisms, but the potential effect of such compounds on marine organisms has been overlooked. Here, it was evaluated whether the chronic exposures (i.e., seven days) to the fire suppressors Ageofoam, Cold Fire, Kidde and Argus could affect the reproduction of the copepod Nitocra sp. The tested concentrations consisted of those recommended on the products’ manuals and those ranging between 0.0001% and 1%. For each compound, the effective concentrations to 50% exposed organisms (EC50) and the lowest observed effect concentrations (LOEC) were estimated. All the fire suppressors exhibited high toxicity, causing fecundity reduction. At the recommended dilutions, 100% lethality occurred for all compounds. The EC50 values ranged from 0.00817% - Ageofoam - to 0.03081% - Argus. The LOECs ranged from 0.001% - Ageofoam - to 0.1% - Argus and Kidde; and were much lower than the concentrations recommended for commercial use. The fire suppressors showed high toxicity to the copepod, reducing the reproduction rates, even in very low concentrations, suggesting that the release of such substances in the estuary caused severe effects to the environment. This assessment provides subsides to the environmental regulation of fire suppressors in Brazil, because these compounds do not have national regulations for their use and disposal

Toxicidade aguda e contaminação por metais em sedimentos do rio dos Bugres, Ilha de São Vicente, SP.

A contaminação de ambientes aquáticos em regiões costeiras, especialmente nos sistemas estuarinos, tem sido frequentemente associada às atividades antropogênicas e aumento da densidade populacional. Contaminação provoca graves efeitos sobre a biota e pode causar riscos ecológicos e ameaças à saúde humana. O presente estudo investigou a qualidade dos sedimentos do Rio dos Bugres, um corpo d’ água pequeno localizado no Sistema Estuarino de Santos e São Vicente (SESS). Os sedimentos de quatro locais distribuídos ao longo deste estuário foram coletados por meio de um amostrador van Veen e avaliados quanto à toxicidade aguda, por meio da utilização de testes de toxicidade com o anfípodo Tiburonella viscana. As texturas dos sedimentos foram estimadas pelo método de peneiramento a seco, e análises químicas foram feitas por ICP OES para a determinação da concentração de metais. Para interpretar os resultados e estimar o grau de poluição, fator de enriquecimento (EF) foi aplicado aos dados químicos. Todos os sedimentos exibiram toxicidade aguda e contaminação por metais. Foram encontradas concentrações elevadas de vários elementos, Hg, Cr, Cu, Ag, Be, Ba, Zn, Ni, Cd e Pb, e os valores excederam as diretrizes de qualidade de sedimentos locais e internacionais para o Cd (> 0,7 mg/kg), Pb (> 10,3 mg/kg), Cu (> 18,7 mg/kg), Ni (> 3,89 mg/kg), Hg (>0,08 mg/kg) e Zn (> 37,9 mg/kg). As concentrações foram influenciadas pela localização e texturas dos sedimentos, e aqueles mais arenosos exibiram concentrações relativamente mais baixas de metais. O estudo mostrou toxicidade e contaminação dos sedimentos do Rio dos Bugres, possivelmente devido às contribuições advindas do antigo lixão de Sambaiatuba, das favelas e palafitas instaladas ás margens do rio e à drenagem dos bairros próximos, que não dispõem ainda de serviço de coleta e tratamento do esgoto e lixo. 

Sediment quality assessment of the tributaries of the Santos-São Vicente Estuarine System – Brazil

The Santos-São Vicente Estuarine System has a long history of environmental impacts, and several studies have been performed in this region. However, the quality of its tributaries was not previously studied. This study aimed to investigate the quality of sediments from five rivers (Santana, Mariana, Piaçabuçu, Quilombo, and Diana Rivers) and three sampling sites at Piaçaguera Canal (riverbed, right and left banks), by using an integrated approach involving chemical analyses and whole sediment toxicity tests. Chronic and acute toxicity tests were performed using, respectively, copepods Nitocra sp. and amphipods Tiburonella viscana. The studied sediments presented moderate to high levels of PAHs, PCBs, metals (Cu, Hg, Ni, Pb, Zn), and As. The majority of sediments produced chronic toxic effects, and samples from Piaçaguera Canal were consistently toxic in all acute and chronic tests. The integration of data through multivariate analyses indicated that the toxicity was closely related to the sediments contamination. Chemical data were compared with sediment quality guidelines, which evidenced that the site-specific values are adequate to predict impacts. The levels of organic chemicals and metals suggest constant inputs from diffuse and point sources, demanding actions to ensure effective control and management of the contamination sources to the estuary

Biodegradability of anionic surfactants in sea water

Com a finalidade de avaliar a biodegradabilidade de quatro tensoativos aniônicos (ASSL, DSS, n-DBSS, TPBSS) em água do mar, foram realizados testes, de 19 dias, seguindo o método exigido pelo Ministério da Saúde para a aprovação de produtos comerciais. Esse método sofreu modificações para que pudesse ser realizado em água do mar uma vez que foi originalmente descrito para água doce. Essas modificações foram consideradas satisfatórias uma vez que o inóculo manteve-se ativo até o final do teste. Com base nos resultados dos testes, há evidências de que o processo de biodegradação ocorre mais lentamente em água do mar do que em água doce.In order to evaluate the biodegradability of four anionic surfactants (LAS, SDS, n-SDBS, STPBS) in sea water, 19-day biodegradation tests were conducted, according to the method required by the Health Ministry for approval of commercial products. This method was modified for testing in sea water, as it originally had been described for freshwater. The modifications were considered sufficient as the microorganisms remain active till the end of the test. The results suggested that the biodegradation process was slower in sea water than in freshwater

Assessing legacy contaminants in sediments from marine protected areas of the central coast of São Paulo (Brazil)

The presence of legacy contaminants in sediments from three Marine Protected Areas (MPAs) of the coast of São Paulo State was evaluated. Four sampling surveys were conducted between 2013 and 2015 in 10 sites, distributed along the Laje de Santos Marine and Xixova-Japui State Parks (PEMLS and XJSP, respectively) and Central Coast Marine Protection Area (APAMLC). Samples were analyzed for sediment texture, total organic carbon, CaCO3, metals (Al, Fe, Hg, Cd, Co, Cr, Cu, Ni, Pb and Zn), aliphatic and polycyclic aromatic hydrocarbons (AH and PAH). Sediments were generally sandy (excepting muddy samples from APAMLC), with variable amounts of TOC, OM and CaCO3. Most of the sediments exhibited low to moderate concentrations of metals, except APAMLC. Low contamination of sediments by hydrocarbons was found but samples from XLSP and APAMLC exhibited the highest concentrations of biogenic AH and PAH from pyrogenic sources. In APAMLC and PEMLS, the levels of metals can be considered as background levels according to geochemical indices (Igeo and EF). In XJSP and especially in APAMLC data indicated poor sediment quality, probably due to the effect of anthropic activities.A contaminação dos sedimentos superficiais foi avaliada neste estudo em amostras de áreas marinhas protegidas (AMP) da costa central de São Paulo. Quatro campanhas de amostragem foram feitas entre 2013 e 2015 em 10 sítios localizados nos Parques Estaduais Marinho da Laje de Santos e Xixová-Japuí (PEMLS e PEXJ, respectivamente), e Área de Proteção Ambiental Litoral Centro (APAMLC). As amostras foram analisadas quanto granulometria, carbono orgânico total, CaCO3, metais (Al, Fe, Hg, Cd, Co, Cr, Cu, Ni, Pb e Zn) e hidrocarbonetos alifáticos(AHs) e policíclicos aromáticos (PAHs). Em geral os sedimentos foram arenosos (exceto aqueles de APAMLC, que foram lamosos) e com quantidades variáveis de COT, MO e CaCO3. A maioria das amostras apresentaram baixas concentrações de metais de acordo com índices geoquímicos (Igeo e fatores de enriquecimento - FE). Baixa contaminação por hidrocarbonetos foi encontrada e em APAMLC os sedimentos apresentaram as maiores concentrações de AHs de origem biogênica e PAHs de pirogênicos. Nos sedimentos de APAMLC e PEMLS, os níveis de metais podem ser considerados como valores de referência. Já em PEXJ, os dados indicaram baixa qualidade de sedimentos, possivelmente devido às fontes antrópicas