Assessment of bioaccumulation of cu and Pb in experimentally exposed spiders, Lycosa terrestris and Pardosa birmanica, using different exposure routes.

Nida Aziz,Hany M Elsheikha,Abida Butt

doi:10.1007/s11356-019-07055-0

Abstract

Major concerns exist regarding the environmental and human health risks caused by exposure to heavy metals. Spiders are often used as a model in ecotoxicological studies to assess soil pollution. Here, we measured the bioaccumulation of copper (Cu) and lead (Pb) in spiders, Lycosa terrestris and Pardosa birmanica, by inductively coupled plasma mass spectrometry (ICP-MS). We investigated whether Cu and Pb accumulation differs according to different spider species, single versus combined metal exposure, and routes of exposure. Spiders were exposed to 10mM CuSO4 and 10mM PbCl2 solutions separately or in combination (10mM + 10mM) through different exposure routes (spiked soil and food) for 6weeks. The effect of metals on the survival and body mass of exposed and unexposed (control) spiders was determined. We found that in both spider species, accumulation of metals increased with exposure time. In single metal exposure, Cu accumulation from food was higher than soil exposure in both spider species, whereas the opposite was observed for Pb. The simultaneous uptake of Cu and Pb significantly decreased from food and soil, respectively. Soil exposure caused more accumulation of metals in L. terrestris than P. birmanica. Metal exposure via contaminated food caused higher mortality compared to soil exposure. Body mass of both spider species was significantly decreased and negatively correlated with metal's concentration. Overall, our results show that bioaccumulation efficiency of Cu and Pb differs significantly in spiders exposed to metal's mixture compared to single metal exposure and is dependent on the exposure route, the type of metal, and spider species. More understanding of the effects of exposure to metal mixture and exposure routes is essential for designing and supporting risk assessment and ecological monitoring programs.

Highlights

Industrial activities and agriculture practices have resulted in release of large amounts of metals into the environment, posing risks to human and environmental health (Wongsasuluk et al 2014, Shulman et al 2017).Copper (Cu) and lead (Pb) are common metals in soil ecosystems and are often found together in high concentrations especially near industrial areas and in agricultural fields irrigated with urban and industrial wastewaters (Iqbal and Khera 2015; Ahmad et al 2018)
The present study investigated the effect of exposure of spider species, Lycosa terrestris and Pardosa birmanica, to Cu and Pb on their survival and body mass change (BMC)
Our results showed that bioaccumulation of Cu and Pb differed significantly in spiders exposed to combined metals compared to a single metal exposure, and was dependent on exposure route, type of metal and spider species

Summary

Introduction

Industrial activities and agriculture practices have resulted in release of large amounts of metals into the environment, posing risks to human and environmental health (Wongsasuluk et al 2014, Shulman et al 2017).Copper (Cu) and lead (Pb) are common metals in soil ecosystems and are often found together in high concentrations especially near industrial areas and in agricultural fields irrigated with urban and industrial wastewaters (Iqbal and Khera 2015; Ahmad et al 2018). Cu is a crucial element for normal physiological functions in organisms, but can be toxic at high concentrations and cause oxidative damage in cells by generating free radicals (Gaetke et al 2014; Zeeshan et al 2016). Free Cu ions bind with thiol group of membrane protein and disrupt its structure and function (Holmstrup et al 1998; Huang et al 2012). Pb represents a risk for terrestrial organisms due its high toxicity and long-term retention time in the environment (Kumar et al.1995; Peterson et al 2017). Pb is a redox inactive metal which produce oxidative stress indirectly by binding with sulfhydryl group of proteins and cause depletion of glutathione, alteration of Ca hemostasis, DNA damage and

Methods

Results

Discussion

Conclusion