ECOTOXICOLOGICAL BIOASSAYS OF THE EARTHWORMS <i>ALLOLOBOPHORA CALIGINOSA</i> SAVIGNY AND <i>PHERETIMA HAWAYANA</i> ROSA TREATED WITH ARSENATE

Abstract

Little research has been carried out on the effect of arsenate on earthworms. Ecotoxicological laboratory tests are fundamental tools for assessing the toxicity of arsenate to soil organisms. In this study, the impact of arsenate on the survival, reproduction and behaviour of the endogenic earthworms Allolobophora caliginosa and the anecic earthworms Pheretima hawayana has been quantified. The 96-h LC 50 of arsenate was estimated as 233.43 mg arsenate Kg −1 soil. d.w. for P. hawayana which is significantly higher than that of A. caliginosa 147.24±27.16 mg arsenate kg −1 soil d.w. The number of juveniles of P. hawayana was significantly higher than that of A. caliginosa at the arsenate concentrations 180, 240 and 400 mg kg −1 soil dry weight. With the exception of the control (6.5 mg arsenate kg −1 soil.d.w.), P. hawayana showed an avoidance behaviour for soils treated with all tested concentrations. A. caliginosa preferred soils treated with 6.5, 60, 110, 180 mg arsenate kg −1 soil d.w., while the avoidance behaviour has been recorded only at 240 and 400 mg arsenate kg −1 soil. d.w. This means that A. caliginosa individuals feed less when exposed to arsenate. On the contrary, the P. hawayana worms could be escaped into their deep vertical burrows when exposed to arsenate.

Effects of metal contaminated soils on Eisenia fetida (Savigny) at Ludhiana (Punjab), India

“…Relationship between arsenic (As) contamination of abandoned mine sites in Korea and the average weight of earthworms was found significant by Shin et al (2007). It was observed by Khalil (2013) that earthworms Allolobophora caliginosa feed less and Pheretima hawayana escaped into their burrows when exposed to arsenate. Miguel et al (2012) revealed in a study that weight and mortality of worms were significantly affected by high levels of heavy metals.…”

Negative Effect of Phosphogypsum Over Physiological Activity of Earthworm Eisenia Fetida

“…Here it is important to mention that Cadmium is one of the heavy metal present in the phosphogypsum beyond the recommended range. It was observed (Khalil, 2013) that earthworms Allolobophora caliginosa feed less and Pheretima hawayana escaped into their burrows when exposed to arsenate. Miguel et al (2012) revealed in a study that weight and mortality of the worms were significantly affected by high levels of heavy metals.…”

“…Impact can vary due to the different contact times during which the earthworm exposed to contaminants (Haghparast;2013;Golchin et al, 2013). Concentration of the metals in the body of earthworms can reach the toxic level if the contact time of earthworm is a prolonged duration (Hagparast et al, 2013).…”

Efeitos Tóxicos de Arsênio em Eisenia Andrei em Exposição a Solos do Entorno de Minerações de Ouro

“…Estudos específicos relacionados à toxicidade de As em oligoquetas são relativamente raros (Khalil, 2013), e as informações existentes desse grupo não se referem a E. andrei. Para Lumbricus terrestris, Meharg et al (1998) Apesar disso, a forma pentavalente predomina nos solos naturais, o que também se acredita acontecer nos solos avaliados nesse estudo, dada a maior similaridade dos valores encontrados com aqueles associados a essa forma química do As.…”