Influence of static and fluctuating salinity on cadmium uptake and metallothionein expression by the dogwhelk Nucella lapillus (L.)
نویسندگان
چکیده
The aim of this study was to investigate the effect of salinity on cadmium (Cd) accumulation and metallothionein (MT) expression in the dogwhelk Nucella lapillus (L.). Adult dogwhelks (shell length: 23.4F1.3 mm) were acclimated to salinity of 33 psu (control), 22 or 11 psu under controlled laboratory conditions (9.5 jC; pH 7.9) for 10 days in a stepwise manner by reducing the salinity by 5.5 psu day . Ten treatment groups were used and comprised five salinity regimes (three fixed salinity [33, 22 or 11 psu] and two fluctuating salinity [varied daily between 33 and 22 psu or 33 and 11 psu in a cyclic manner]) at each of two Cd concentrations (control: <0.001 Ag Cd l 1 or treatment: 500 Ag Cd l ). After acclimation, groups of 20 dogwhelks were exposed to each of the 10 Cd/salinity combinations. All the control and Cd-exposed dogwhelks exposed to 11 psu were dead within 5 days of exposure due to hypo-osmotic stress. Twenty days after exposure to all other treatments, concentrations of Cd and MTs in the tissues of surviving dogwhelks were quantified using atomic absorption spectrophotometry and the silver saturation method, respectively. Both Cd accumulation and MT induction in control or Cd-exposed N. lapillus were significantly influenced by changes in salinity, especially at a prolonged and fixed low salinity (22 psu), although such influences of salinity on the concentration of MTs were dependent on the tissue type. The study highlights that salinity should be considered when monitoring trace metals and/or MTs in intertidal molluscs, particularly in estuarine or transplanted biomonitors. D 2002 Elsevier Science B.V. All rights reserved.
منابع مشابه
AFLPs Reveal Different Population Genetic Structure under Contrasting Environments in the Marine Snail Nucella lapillus L.
Dispersal has received growing attention in marine ecology, particularly since evidence obtained with up-to-date techniques challenged the traditional view. The dogwhelk Nucella lapillus L., a sedentary gastropod with direct development, is a good example: dispersal was traditionally assumed to be limited until studies with microsatellites disputed this idea. To shed some light on this controve...
متن کاملGrowth rate as a factor confounding the use of the dogwhelk Nucella lapillus as biomonitor of heavy metal contamination
Growth rate of individually tagged dogwhelks Nucella lapillus (L.) was measured in free-living individuals at 3 sites of differing heavy metal contamination in the Firth of Clyde, west Scotland. Condition index (CI), concentrations of metals (Cd, Cu, Pb and Zn), metallothionein (MT), RNA (the RNA/protein ratio) and glycogen were also measured. In general, the marine environments of Gourock and ...
متن کاملImposex in the dogwhelk (Nucella lapillus): 22-year monitoring around England and Wales
Six imposex surveys in the dogwhelk (Nucella lapillus) have been conducted over the past two decades to assess legislation effectiveness controlling the use of tri-butyl tin (TBT) by the maritime shipping industry. This study firstly analysed the results of the 2014 survey and secondly carried out a trend assessment of the same 88 sampled sites between 1997 and 2014 of which 65 showed statistic...
متن کاملBehavior and morphology of Nucella lapillus influenced by predator type and predator diet
To reduce their risk of being eaten, prey may change their morphology or behavior in response to predators, which can result in slower growth and lower fitness. To minimize costs, prey limit anti-predator responses to risky situations, which requires prey to reliably detect cues indicative of predation risk. The purpose of this study was to ascertain how different types of risk cues would affec...
متن کاملHistorical shell size reduction of the dogwhelk (Nucella lapillus) across the southern UK
Body size reduction is predicted to be one of the most common ecological responses to climate change, yet examples within some taxonomic groups, such as marine molluscs, are rare. Here, we document a significant reduction in shell size of the rocky shore gastropod Nucella lapillus across the southern UK using natural history collections and modern field data. These results are correlated with t...
متن کامل