Occurrence of imposex in Thais haemastoma: possible evidence of environmental contamination derived from organotin compounds in Rio de Janeiro and Fortaleza, Brazil

Abstract

There are indications that the widespread use of organotin compounds (TBT and TPT) as antifoulings, as stabilizers in plastic and as pesticides, has severely affected several species of marine organisms. The most striking effect of TBT and TPT as hormonal disruptors is the development of male organs in females of gastropods, currently denominated imposex. This syndrome can lead to the sterilization and death of affected organisms. The present work gives an overview of the present state of knowledge on imposex occurrence and reports results of a survey conducted in Guanabara Bay, Rio de Janeiro and in several sites along the coast of Fortaleza, Ceará State. Different stages of imposex development were verified in this survey, however, the most prominent levels appeared associated to known spot sources of TBT and TPT.

Direct electrochemical analysis of dexamethasone endocrine disruptor in raw natural waters

“…However, this trick has become very limited due to the irregular rainfall season and sometimes to the low accumulated volume. 3 In addition, the combination Vol. 23, No.…”

Imposex in endemic volutid from Northeast Brazil (Mollusca: Gastropoda)

“…The reliability of this bioindicator is derived from the fact that imposex originates in one highly specific hormonal alteration, occurring just in gastropods exposed to organotin compounds (Matthiessen and Gibbs, 1998). More than a hundred gastropod species exhibited this response in a worldwide scale (Fioroni et al, 1991;Gibson and Wilson, 2003). Although imposex has already been observed in some studies in Latin America (Gooding et al, 1999;Penchaszadeh et al, 2001;Bigatti and Penchaszadeh, 2005;Cledòn et al, 2006), no monitoring studies over large areas have been carried out in this region.…”

“…In Central Chile, Osorio and Huaquín (2003) found symptoms of populational decline within populations of the muricid Acanthina monodon, found in the proximity of port terminals. In Brazil, imposex was observed in the muricids Stramonita haemastoma (Castro et al, 2000;Fernandez et al, 2002;Fernandez et al, 2005), Stramonita rustica (Camillo et al, 2004;Castro et al, 2004), and in the olivid Olivancillaria vesica (Caetano and Absalão, 2003). Voluta ebraea (Fig.…”

Síntese e caracterização de um novo composto obtido pela reação entre hidreto de trifenilestanho e ácido (±)-mandélico e avaliação de seu potencial biocida sobre o fungo Fusarium oxysporum f. sp. cubense

“…Estas placas foram vedadas e levadas a uma câmara de incubação a 23-25 o C durante 6-8 dias. Durante este período de crescimento, a cada 2-3 dias, foram feitas medições ortogonais do dos diâmetros das colônias com o uso de paquímetro, tendo como referência o crescimento da placa testemunha preenchida (DIAS, 1999;FERNANDEZ, 1993;SILVA, 2000).…”

“…Cada placa de teste continha uma lâmina de vidro, sobre a qual colocouse 20 mL de solução do composto organoestânico na concentração de 500 ppm e 20 mL de solução micelial do Fusarium oxysporum. Depois de 10 horas em câmara a 18 o C, adicionou-se 20 mL de solução do corante Lacto Fenol/ Azul de Tripan, levou-se ao microscópio, com aumento de 40x, para contagem de conídios e microconídios, germinados e não-germinados, em cada um dos quatro quadrantes das amostras nas lâminas, sendo os resultados expressos como médias aritméticas simples (DIAS, 1999;FERNANDEZ, 1993;SILVA, 2000 O composto organoestânico obtido, de cor branca, quando observado ao microscópio, apresenta natureza microcristalina. Nas tentativas para recristalização do sólido obtido, não foi possível a obtenção de monocristais com características adequadas para determinação de estruturas por difratometria de raios-X.…”