Laboratório de Mamíferos Aquáticos e Bioindicadores ''Prof(a). Izabel Gurgel'' (MAQUA), Faculdade de Oceanografia, Universidade Do Estado Do Rio de Janeiro, Rua São Francisco Xavier, 524, Sala 4002, CEP 20550-013, Maracanã, Rio de Janeiro, RJ, Brazil; Programa de Pós-Graduação Em Ciências Biológicas (Biofísica), Universidade Federal Do Rio de Janeiro, Av. Carlos Chagas Filho, 373, CEP 21941-902, Rio de Janeiro, RJ, Brazil.
Laboratório de Mamíferos Aquáticos e Bioindicadores ''Prof(a). Izabel Gurgel'' (MAQUA), Faculdade de Oceanografia, Universidade Do Estado Do Rio de Janeiro, Rua São Francisco Xavier, 524, Sala 4002, CEP 20550-013, Maracanã, Rio de Janeiro, RJ, Brazil.
Chemosphere. 2021 Jan;263:128286. doi: 10.1016/j.chemosphere.2020.128286. Epub 2020 Sep 13.
An unusual mortality event (UME) attributed to morbillivirus infection was identified in two Guiana dolphin populations from the Southeastern Brazilian coast. The aim of this study was to characterize total mercury (THg), methylmercury (MeHg) and selenium (Se) bioaccumulation and body burden in Guiana dolphins from Sepetiba Bay (RJ) collected before (n = 61) and during the UME (n = 20). Significantly lower Se concentrations were found in the livers of individuals collected during the UME (Mann-Whitney test; p = 0.03), probably due to impairment of the detoxification process in the liver. There were differences in THg and Se concentrations in the organs and tissues of individuals (Kruskal-Wallis test, p < 0.05), but not MeHg (Kruskal-Wallis test, p = 0.07). For THg, the liver showed the higher concentrations and differed among organs and tissues analyzed such as blubber (Tukey's test for unequal N; p = 0.003). For Se concentrations, the skin and kidney presented the higher concentrations and varied among other tissues/organs, like muscle (Tukey's test for unequal N; p = 0.02). Differences in body burdens were observed among specimens collected previously and during the UME probably due to the remobilization and transport of the muscle-stored MeHg to other tissues/organs. This abrupt input of MeHg into the bloodstream may cause serious health damage. Indeed, evidences of methylmercury intoxication was observed in Guiana dolphins in Sepetiba Bay. In conclusion, bioaccumulation patterns, the detoxification process and body burden were affected by morbillivirus.
在巴西东南海岸的两个瓜纳亚那海豚种群中，发现了一起归因于麻疹病毒感染的异常死亡率事件（UME）。本研究的目的是描述塞佩提巴湾（里约热内卢州）瓜纳亚那海豚的总汞（THg）、甲基汞（MeHg）和硒（Se）生物积累和体内负荷，这些海豚是在 UME 之前（n=61）和期间（n=20）采集的。在 UME 期间采集的个体肝脏中发现 Se 浓度显著降低（Mann-Whitney 检验；p=0.03），这可能是由于肝脏解毒过程受损。个体器官和组织中 THg 和 Se 浓度存在差异（Kruskal-Wallis 检验，p<0.05），但 MeHg 浓度无差异（Kruskal-Wallis 检验，p=0.07）。对于 THg，肝脏的浓度最高，且在分析的器官和组织之间存在差异，如鲸脂（Tukey 检验，不等 N；p=0.003）。对于 Se 浓度，皮肤和肾脏的浓度最高，且在其他组织/器官之间存在差异，如肌肉（Tukey 检验，不等 N；p=0.02）。在 UME 之前和期间采集的标本中观察到体内负荷的差异，这可能是由于肌肉中储存的 MeHg 向其他组织/器官的重新动员和运输所致。这种 MeHg 突然进入血液可能会导致严重的健康损害。事实上，在塞佩提巴湾的瓜纳亚那海豚中观察到了甲基汞中毒的证据。总之，生物积累模式、解毒过程和体内负荷都受到麻疹病毒的影响。
