Variation in the response of juvenile and adult gastropods (Lymnaea stagnalis) to cyanobacterial toxin (microcystin-LR)

Abstract

Owing to the increasing public health problem related to the proliferation of toxin-producing cyanobacteria in aquatic ecosystems, we have investigated the response of the pond snail Lymnaea stagnalis exposed to 33 microg/L microcystin-LR for 6 weeks, through its life traits (survival, growth, fecundity) and locomotion; uptake of microcystin-LR was also quantified in the snail body tissues. To study the potential plasticity of the response related to the development stage, snails were exposed to the toxin as sexually immature and mature. According to our results, microcystin-LR accumulated in snail tissues at a higher level in juveniles (7.96 ng/g fresh weight) versus adults (2.17 ng/g fresh weight). Whatever the age, survival, growth, and locomotion were not affected by the toxin, and fecundity of polluted adults was reduced by half. These results are discussed in terms of negative effects of aqueous microcystin-LR occurrence on the dynamics of natural populations of gastropods.

Transfer, distribution and bioaccumulation of microcystins in the aquatic food web in Lake Taihu, China, with potential risks to human health

“…Ding et al (2006) pointed out that when male mice exposed intraperitoneally to 3.33 or 6.67 μg/g microcystins/kg body weight for 14 days, their mean body weight decreased, seminiferous tubules were damaged, the quality of mature sperm in the seminiferous tubules was decreased and the motility and viability of the sperm were reduced. Gérard et al (2005) reported that when the pond snail L. stagnalis were exposed to 33 μ g/L MC-LR for a period of 6 weeks, survival, growth, and locomotion of the snail were not affected, but their fecundity decreased to half. Baganz et al (1998) reported that when zebrafish (Danio rerio) were exposed to 50 μg/L MC-LR, their spawning activity and success were reduced.…”

Oxidative stress responses and toxin accumulation in the freshwater snail Radix swinhoei (Gastropoda, Pulmonata) exposed to microcystin-LR

“…However, the effects of MCs on snails have been rarely investigated. Gérard et al (2005) initially confirmed that MCs can decrease the survival, growth, and fecundity of Lymnaea stagnalis after 35 days of exposure. Furthermore, toxic cyanobacteria or MCs adversely affect the histopathological characteristics, reproduction, and community structure of L. stagnalis (Lance et al 2007;Gérard et al 2009;Lance et al 2011).…”

Bioaccumulation of microcystins in two freshwater gastropods from a cyanobacteria-bloom plateau lake, Lake Dianchi

“…It has been proposed that MCs are likely transferred from adult females to offspring (Zhang et al, 2007). Decreased fecundity has also been demonstrated after exposure to intracellular MCs (ingestion of cyanobacteria) (Gérard et al, 2005). In fact, impact of MCs on gonads and on life-history traits may directly impair the population dynamics of gastropods (Lance et al, 2011).…”

“…5). Apparently a detoxification mechanism exists in the hepatopancreas after a certain adaptive phase of exposure to high (Gérard et al, 2005;Xie et al, 2007). Lance et al (2006Lance et al ( , 2010a indicated that gastropods can eliminate free MCs and probably can even bind MCs during the renewal of proteins phosphatase.…”

“…The various organs have different structures and functions, possibly resulting in their different abilities for bioaccumulation of MCs (Ozawa et al, 2003;Xie et al, 2007). However, up to now almost all the research about accumulation of MCs for pulmonates have been studied with regard to the whole body level (Kotak et al, 1996;Zurawell et al, 1999;Gérard et al, 2005Gérard et al, , 2009Lance et al, 2010a), and several at the digestive gland level (Lance et al, 2006;Zurawell et al, 2006Zurawell et al, , 2007, but fewer in other tissues.…”