Long-term effect of diet amended by risk elements contaminated soils on risk element penetration and physiological parameters of rats

Abstract

ABSTRACT:The long-term accumulation of risk elements (As, Cd, Pb) originated from differently contaminated soils in rat organism was investigated during a model two-generation experiment. The effect of soil contamination level, gender, and length of exposure as well as the interactions between risk elements and selected essential macro-and microelements were studied. Rat diet contained 10% of individual soils (based on dry weight): (i) Fluvisol heavily polluted by As, Cd, Zn, and Pb, (ii) Luvisol contaminated by As, Cd, and Zn, and (iii) uncontaminated Chernozem. Male and female Wistar rats used for the experiment were housed in cages in a room with controlled temperature for 60 days and were fed ad libitum the mentioned diets. Subsequently, the pregnant females were continuously fed the experimental diet until weaning when the young animals were separated to male and female and fed the experimental diet till day 110 of age. The element contents in rat tissues reflected the risk element contents in contaminated soils. The bioaccessibility and bioavailability of the risk elements decreased in the order Cd>As>Pb and was affected by the soil physicochemical parameters. No significant differences were observed between male and female rats as well as between the first and the second generation. However, interactions were reported among the risk elements where the high cadmium content in Fluvisol resulted in increasing arsenic accumulation in the rat liver. Moreover, arsenic-copper interactions were observed where significant increase of the copper level was determined in kidney of the animals fed Luvisol exceeding 50-fold the maximum permissible limits for As content in agricultural soils. Among the hematological and biochemical characteristics of rats, total erythrocyte count (Er), hematocrit (Hct) increased confirming adverse effect of soil-derived risk elements especially in male rats.

The oral bioavailability of soil-borne risk elements for small terrestrial mammals: Microtus arvalis (Pallas, 1778) and Apodemus sylvaticus L. and its implication in environmental studies

“…Additionally, competition with REs during uptake, absorption, and deposition may reduce the nal concentrations of essential elements in animal tissues(Whittaker et al 2011;Wang et al 2009). For instance, decreasing Zn levels in the organism exposed to elevated rates of Cd was published byMatovic et al (2012), and similar pattern was observed in our previous experiments with rat model(Vlčková et al 2014). The bioavailability of soil-borne elements depends on the characteristics of the soil (soil pH, element species in the soil, element binding on the soil particles, etc.…”

“…Individals in control group recieved 139 ± 26 grams of fresh clover-grass biomass for the same period. The 10% w/w rate of soil was chosen according to our previous experiments with laboratory rat model (Vlčková et al 2014, Száková et al 2012). The element contents in the individual components of the diets are summarized in Table 1.…”

“…However, the RE uptake and especially the uptake of soil-borne elements cannot be unambiguously estimated from the results of the monitoring provided in the contaminated areas. Therefore, the effect of a diet amended with soil contaminated with As, Cd, and Pb on the element uptake and physiological and hematological parameters was previously investigated in laboratory conditions using a rat model (Mascolo et al 2004;Vlčková et al 2014;Száková et al 2012). However, the physiological and metabolic differences between laboratory strains of rodents (Rattus and Mus) and common wild species such as Microtus, Apodemus, Myodes etc.…”

“…Moreover, substantial changes in the mobile proportions of elements can occur in the digestion tract due to the reactions of the soil particles and other components of the diet with the gastric and intestinal uids(Yang 2010). The response of the animal organisms on the soil-bearing elements as related to the physicochemical parameters of the soils presentedVlčková et al (2014) for the rat model. In their experiment, the bioavailability of the elements decreased in order Cd > As > Pb.…”

The oral bioavailability of soil-borne risk elements for small terrestrial mammals: Microtus arvalis (Pallas, 1778) and Apodemus sylvaticus L. and its implication in environmental studies

“…However, the RE uptake and especially the uptake of soil-borne elements cannot be unambiguously estimated from the results of the monitoring provided in the contaminated areas. Therefore, the effect of a diet amended with soil contaminated with As, Cd, and Pb on the element uptake and physiological and hematological parameters was previously investigated in laboratory conditions using a rat model (Mascolo et al 2004 ; Vlčková et al 2014 ; Száková et al 2012 ). However, the physiological and metabolic differences between laboratory strains of rodents ( Rattus and Mus ) and common wild species such as Microtus , Apodemus , and Myodes pose the pitfall of this methodological approach.…”