Tintas usadas no revestimento de estruturas portuárias fixas: Composição, bioacumulação e toxicidade sobre ostras da espécie Crassostrea brasiliana
Arquivos
Data
2020-04-28
Autores
Chiovatto, Ana Cristina Lazzari 
Orientadores
Castro, Ítalo Braga
Tipo
Dissertação de mestrado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
Poluição resultante do lançamento de produtos químicos perigosos no ambiente está entre as principais causas de perda da biodiversidade. Tintas utilizadas para evitar a incrustação marinha e impermeabilizar superfícies em contato direto com o mar tem sido alvo de grande preocupação recente. A maior parte, destas estruturas fixas em terminais portuários são confeccionadas em concreto e estão sujeitas a incrustação e desgaste causado pelo contato com a água do mar. Para minimizar o impacto sobre as estruturas, a tinta Lackpoxi Alcatrão de Hulha N 1761 (LAC) é utilizada com finalidades anti-incrustantes e impermeabilizantes. Em contato com a água, esse produto pode liberar resíduos causando efeitos deletérios sobre a biota local. Tal situação é ainda mais grave considerando que essas tintas são aplicadas durantes as marés baixas e entram em contato com a água poucas horas após pintura. Apesar disso, nenhum estudo avaliou a potencial toxicidade deste tipo de revestimento sobre organismos aquáticos. Sendo assim, o objetivo do presente estudo foi avaliar a composição, a bioacumuação e a toxicidade desse produto sobre ostras da espécie Crassostrea brasiliana. Para tanto um experimento de exposição usando estacas de concreto em miniatura pintadas com a tinta LAC foi realizado em escala de laboratório. Paralelamente as concentrações de 12 elementos traço e 16 HPAs foram determinadas analiticamente na matriz da tinta, na água do meio de exposição e nos tecidos os organismos expostos. Elevadas concentrações dos elementos e de HPAs foram verificadas a matriz da tinta. Entretanto, no meio de exposição não foi possível verificar variações nas concentrações dos elementos analisados. Por outro lado, aumentos abruptos nas concentrações de HPAs foram vistos tanto em 48, como em 96 horas de exposição. Essas variações foram acompanhas por um aumento proporcional na bioacumulação desses compostos nos tecidos de ostras. Entre os elementos, apenas o Cd, Pd e Sn mostraram variações significativas em tecidos de ostras. Essas observações indicam que ambos os grupos de compostos analisados são lixiviados a partir do produto estudado podendo causar contaminação. Adicionalmente os organismos expostos durante o procedimento experimental mostraram uma redução significativa da integridade das membranas lisossômicas de seus hemócitos. Considerando que esse tipo de resposta é universalmente aceita como um marcador do estado de saúde geral dos organismos, os efeitos resultantes da exposição a tinta apresentam potencial para induzir severos danos ambientais. Portanto, organismos habitantes de zonas onde procedimentos de pintura usando o produto estejam sendo aplicados, estão provavelmente expostos a severas ameaças químicas que podem levar a danos fisiológicos irreparáveis. Assim, baseado no exposto se recomenda que o produto seja banido para utilização em zonas costeiras.
Pollution resulting from discharges of hazardous chemicals are among the main causes of biodiversity loss. Paints based in chemicals substances and used to prevent fouling and provide waterproof surfaces have been recently of major environmental concern. Despite this, concrete static structures in ports are subject to environmental stressors able to cause damages. To minimize the impact on these structures, the paint Lackpoxi Coal Tar N 1761 (LAC) is used as protective coating. However, the seawater contact can release harmful substance which may affects the local biota. Such a situation is more serious considering that these products are only applied during low tides and come into contact with water few hours after painting. Despite this, any study has evaluated the potential toxicity of this type of coating on aquatic organisms. Thus, the objective of the present study, was to assess chemical composition, bioaccumulation rates and toxicity of this paints on oysters (Crassostrea brasiliana). For that, experimental study using miniature concrete stakes painted with LAC paint, was carried out in laboratory scale. Simultaneously, concentrations of 12 trace elements and 16 PAHs were analytically determined from the paint matrix, in seawater exposure media and in tissues of exposed organisms. High concentrations of elements and PAHs were verified in the paint matrix. However, in the exposure it was not possible to verify variations in the levels of the analyzed elements. On the other hand, sharp increases in PAH concentrations were seen in both, 48 and 96 hours of exposure. These variations were accompanied by a proportional increase in the bioaccumulation rates of these compounds in oyster tissues. Among elements, only Cd, Pd and Sn showed significant variations in oyster tissues. These findings indicate that analyzed substances are leached from the studied paint, and can cause environmental contamination. In addition, the organisms exposed during the experimental procedure showed a significant reduction in the integrity of the lysosomal membranes of their hemocytes. Considering that this type of response is universally accepted as a marker of the general health status, the exposure effects presents potential to induce severe environmental damage. Therefore, organisms inhabiting areas where painting procedures using this product are being applied, are probably exposed to severe chemical threats that can lead to irreparable physiological damages. Therefore, based on the above, it is recommended that the product be banned for use in coastal areas.
Pollution resulting from discharges of hazardous chemicals are among the main causes of biodiversity loss. Paints based in chemicals substances and used to prevent fouling and provide waterproof surfaces have been recently of major environmental concern. Despite this, concrete static structures in ports are subject to environmental stressors able to cause damages. To minimize the impact on these structures, the paint Lackpoxi Coal Tar N 1761 (LAC) is used as protective coating. However, the seawater contact can release harmful substance which may affects the local biota. Such a situation is more serious considering that these products are only applied during low tides and come into contact with water few hours after painting. Despite this, any study has evaluated the potential toxicity of this type of coating on aquatic organisms. Thus, the objective of the present study, was to assess chemical composition, bioaccumulation rates and toxicity of this paints on oysters (Crassostrea brasiliana). For that, experimental study using miniature concrete stakes painted with LAC paint, was carried out in laboratory scale. Simultaneously, concentrations of 12 trace elements and 16 PAHs were analytically determined from the paint matrix, in seawater exposure media and in tissues of exposed organisms. High concentrations of elements and PAHs were verified in the paint matrix. However, in the exposure it was not possible to verify variations in the levels of the analyzed elements. On the other hand, sharp increases in PAH concentrations were seen in both, 48 and 96 hours of exposure. These variations were accompanied by a proportional increase in the bioaccumulation rates of these compounds in oyster tissues. Among elements, only Cd, Pd and Sn showed significant variations in oyster tissues. These findings indicate that analyzed substances are leached from the studied paint, and can cause environmental contamination. In addition, the organisms exposed during the experimental procedure showed a significant reduction in the integrity of the lysosomal membranes of their hemocytes. Considering that this type of response is universally accepted as a marker of the general health status, the exposure effects presents potential to induce severe environmental damage. Therefore, organisms inhabiting areas where painting procedures using this product are being applied, are probably exposed to severe chemical threats that can lead to irreparable physiological damages. Therefore, based on the above, it is recommended that the product be banned for use in coastal areas.
Descrição
Citação
CHIOVATTO, Ana Cristina Lazzari. Tintas usadas no revestimento de estruturas portuárias fixas: Composição, bioacumulação e toxicidade sobre ostras da espécie Crassostrea brasiliana. 2020. 55 f. Dissertação (Mestrado em Biodiversidade Marinha e Costeira) - Instituto do Mar, Universidade Federal de São Paulo, Santos, 2020.