Chronic toxicity test with sea urchin Echinometra lucunter and Lytechinus variegatus (Echinodermata: Echinoidea), exposed to light-stick - flag paternoster used for longline surface fishing

Abstract

In this work, the chronic toxicity of a mixture of light-stick chemicals and water was tested. The light-stick is used in fishery activities to catch swordfish. The tubes were collected on the beaches of the Costa dos Coqueiros -BA, Brazil, in the period from 14th to 31st July 2007. The method used was a short chronic toxicity test where embryos of the sea urchins Echinometra lucunter and Lytechinus variegatus were exposed to a stock solution consisting of the supernatant formed from a mixture of sea water and the orange-colored light-stick chemical. After a preliminary test, concentrations defined were 0.002, 0.003, 0.01, 0.02, 0.1, 1.0% of stock solution. The final test ran for 36 hours for E. Lucunter and 24 hours for L. variegatus with 4 replicates for each concentration. The value of EC50 -36h was 0.062% with confidence limits ranging from 0.042 to 0.079% and the EC50 -24h was 0.011% with confidence limits ranging from 0.009 to 0.014%, i.e., the chemical mix present in the light-stick is potentially toxic. So, as these flags are commonly used for fishing there is potential danger in their disposal in the open ocean. RESUMOO objetivo deste trabalho foi avaliar a toxicidade crônica da água do mar em contato com o líquido contido no light-stick, sinalizador utilizado em pesca de espinhel de superfície para a captura de espadarte. Os tubos foram coletados nas praias da Costa dos Coqueiros -BA, no período de 14 a 31 de Julho de 2007. O método utilizado para a verificação da toxicidade crônica foi o teste de curta duração com embriões de ouriço-do-mar Echinometra lucunter e Lytechinus variegatus, os ensaios foram realizados com solução estoque que consiste do sobrenadante formado a partir de uma mistura de água do mar com o líquido do sinalizador de coloração laranja. Após um teste preliminar as concentrações definidas foram 0.002; 0.003; 0.01; 0.02; 0.1; 1.0%. O teste definitivo teve duração de 36 horas para E. lucunter e 24 horas para L. variegatus, sendo preparadas 4 réplicas para cada concentração. O valor da CE50 -36h encontrado foi de 0.062% com limites de aceitabilidade variando de 0.042 a 0.079% e a CE50 -24h encontrada foi de 0.011% com limites de aceitabilidade variando de 0.009 a 0.014%, ou seja, os compostos químicos presentes no light-stick são potencialmente tóxicos. Portanto já que esses sinalizadores são utilizados comumente como petrechos de pesca há a necessidade de que eles sejam recolhidos, pois podem causar efeitos adversos quando abrem nos oceanos.

Thyroid‐like hormone signaling in invertebrates and its potential role in initial screening of thyroid hormone system disrupting chemicals

“…Several researchers have extended the widelyused sea urchin fertilization assay (e.g., Environment Canada, 2011 ) to investigate various aspects of early development in echinoderms, including growth rate (e.g., Saco‐Alvarez et al, 2010 ), developmental delay, and morphological abnormalities up to the pluteus larval stage (e.g., Bellas et al, 2005 ; Cesar‐Ribeiro et al, 2010 ; Anselmo et al, 2011 ; Morroni et al, 2016 ; Picone et al, 2016 ). As indicated previously, it has been demonstrated that exposure to T4, T3, or T2 accelerates the initiation of skeletogenesis (spicule formation) in sea urchin Strongylocentrotus purpuratus gastrulae (2 dpf) and in six‐armed pluteus larvae (10–14 dpf; Taylor and Heyland, 2018 ).…”

Lightsticks cause adverse effects on behavior and mortality of marine mysids Promysis atlantica

“…An average of 13 lightsticks per km was found at the beaches in the Coqueiros coast. The orange color tubes were taken to the laboratory, where they were opened and used to prepare the stock solution used in the toxicity tests (Cesar-Ribeiro & Palanch-Hans 2010, Cesar-Ribeiro et al 2017. The immiscible compounds were extracted through the dissolution of 0.1 mL of lightstick fluids in 100 mL of filtered seawater (salinity of 35) with ethanol 0.5% (v/v) as a solvent [stock solution ethanol (SSE 0.1%)].…”

“…In Brazil, the international non-governmental organization (NGO) Global Garbage executed significant efforts to assess such a problem by collecting and identifying marine litter in beaches from Bahia State (Cesar-Ribeiro & Palanch-Hans 2010, Cesar-Ribeiro et al 2017. As a result, it was possible to identify various debris strongly related to marine vessels as the primary garbage source, potentially harmful to aquatic organisms as the lightsticks, the target object in this study.…”

“…As a result, it was possible to identify various debris strongly related to marine vessels as the primary garbage source, potentially harmful to aquatic organisms as the lightsticks, the target object in this study. It was reported that in distant places, local populations collected lightsticks from the beaches and tried to use the tube content as suntan lotion or for treatment of vitiligo and even mycoses (Cesar-Ribeiro & Palanch-Hans 2010, Cesar-Ribeiro et al 2017. After drifting to the shore, elevated temperatures and solar irradiation indicated the presence of reactive electrophiles and increased cyto and genotoxic potential in human cells forming mutagenic lesions (Oliveira et al 2014).…”

“…The isolation of hydrophilic compounds, i.e. oxalate ester, oxygen peroxide, and the salicylic acid; and hydrophobic compounds: PAH provided evidence of higher toxicity levels in the supernatant fraction that caused chronic toxicity (abnormality of pluteus larvae development) on sea urchins, Echinometra lucunter and Lytechinus variegatus (Cesar-Ribeiro & Palanch-Hans 2010, Cesar-Ribeiro et al 2017.…”