Impact of Soil Cadmium on Land Snails: A Two-Stage Exposure Approach under Semi-Field Conditions Using Bioaccumulative and Conchological End-Points of Exposure

Abstract

Land snails are highly tolerant to cadmium exposure and are able to accumulate soil cadmium independently of food ingestion. However, little information exists on the kinetics of cadmium retention in terrestrial gastropods exposed to an increase in the soil cadmium content, over time. There is also little knowledge about how exposure to cadmium-polluted soils influences shell growth and architecture. In this context, we examined cadmium accumulation in the hepatopancreas and shell of juvenile Cantareus aspersus exposed to elevating high levels of cadmium in soil. Also, the toxicity of cadmium to snails was assessed using a range of conchological endpoints, including shell height, width, volume, allometry and integrity. Test snails, aged three months, were reared under semi-field conditions, fed an uncontaminated diet and exposed first, for a period of 30 days, to a series of soil cadmium concentrations, and then, for a second period of 30 days, to soils with higher cadmium content. Cadmium showed a dose-dependent accumulation in both the hepatopancreas and shell. The kinetics of cadmium retention in the hepatopancreas of snails previously exposed to cadmium-spiked soils was significantly influenced by a new exposure event. The shell was not a relevant bioaccumulator for soil cadmium. Under the present experimental conditions, only high cadmium exposure significantly affected either the shell growth or snail survival. There was no consistent effect on shell allometry, but the shell integrity, especially in rapidly growing parts, appeared to be affected by high cadmium exposure. Our results attest to the value of hepatopancreas for describing cadmium retention in land snails and to the difficulty of using conchological parameters in field surveys for estimating the environmental hazard of soil cadmium.

High-level dietary cadmium exposure is associated with global DNA hypermethylation in the gastropod hepatopancreas

“…aspersus , concentrated substantive amounts of cadmium in the hepatopancreas without significant lethal effects. This is in accordance with the results of other investigations [ 13 , 34 ], confirming the exceptional tolerance of this gastropod species to Cd exposure [ 13 , 16 , 34 , 35 , 52 , 53 ]. Most studies to date found no significant mortality in C .…”

“…There is also compelling evidence for the presence of 5mC in the genome of the land snail Helix pomatia (Linnaeus, 1758) [ 11 ]. However,there is no relevant epigenetic information available concerning other terrestrial gastropods that are commonly used as ecotoxicological study systems, such as the brown garden snail Cantareus aspersus (Müller, 1774)[ 12 – 16 ]or the grove snail Cepaea nemoralis (Linnaeus, 1758)[ 17 , 18 ].…”

Short-term effects of very low dose cadmium feeding on copper, manganese and iron homeostasis: A gastropod perspective

“…Cadmium sulfate will extend our knowledge on the bioavailability of different chemical forms of Cd in land snails, which is currently limited to cadmium chloride (Coeurdassier et al, 2002;Nica et al, 2015;Nica et al, 2017aNica et al, , 2017b and cadmium nitrate (Laskowski and Hopkin, 1996).…”

“…These invertebrates serve as excellent macro-concentrators for cadmium (Dallinger and Rainbow, 1993), with the hepatopancreas being the main retention endpoint (Russel et al, 1981;Rabitsch, 1996;Dallinger et al, 2004;Fritsch et al, 2011;Pauget et al, 2013). Therefore, the concentration of Cd in this organ is a reliable tool for exposure assessment and provides accurate estimates of its bioavailability for these mollusks (Rabitsch, 1996;Nica et al, 2015).…”

Oxidative stress, lipid metabolism, and neurotransmission in freshwater snail (Pomacea patula) exposed to a water-accommodated fraction of crude oil

“…Biomarker evaluation. Test specimens were measured with a Vernier caliper and weighed in analytical balance with a sensitivity of 0.1 g. Organisms were euthanized by fast-freezing them at -20 °C/30 min, as previously reported (Nica et al, 2015). Tissues of tegogolo (foot, head, intestine, mantle, digestive gland, and kidney) were obtained according to the anatomy of gastropods (Barnes, 1980).…”