Trace elements bioaccumulation in Porcellionides pruinosus (Brandt, 1833) and related biomarkers of exposure

First Insights Into Trace Element Accumulation by Philoscia affinis (Crustacea, Isopoda): a Novel Tracer to Assess Soil Contamination in Lowland Plains?

Isopods are terrestrial invertebrates that accumulate trace elements in large quantities, thus providing information on levels of soil contamination. However, the accumulation pattern seems to be species dependent. For this study, specimens of Philoscia affinis (Isopoda, Oniscidea) and soil samples were collected from both a protected area (site 1) and urban roadside (site 2) in the low plain of Friuli-Venezia Giulia (northeast Italy) to determine whether P. affinis could serve as a potential candidate for monitoring soil contamination. To do this, the following objectives were achieved: a) the level of trace elements (Al, Cd, Cu, Fe, Hg, Mn, Pb, Zn) were detected in soils and isopods; 2) the difference in trace elements accumulation was compared in the two sampling sites; 3) the bioaccumulation factor (BAF) was calculated for each element. With some exceptions, trace element concentrations were higher in both isopods and soil samples from the urban roadside compared to the protected area. Furthermore, except for Cd, Cu, and Zn, trace element levels were higher in the soil than in the isopod samples. The higher mean BAF values were recorded for Cd (6.169 and 6.974 for site 1 and 2, respectively), Cu (10.324 and 11.452 for site 1 and 2, respectively), and Zn (1.836 and 2: 1.943 for site 1 and 2, respectively), whereas BAF values <1 were recorded for the other elements. Philoscia affinis was found to be a potential candidate to monitor soil contamination as a macro-concentrator of Cu and Cd and a micro-concentrator of Zn.

Toxicity assessment of nano-TiO2 in Apis mellifera L., 1758: histological and immunohistochemical assays

The aim of this study was to evaluate the toxicity of titanium dioxide nanoparticles (TiO₂ NPs) by short-term toxicity tests in Apis mellifera, considered an excellent bioindicator organism mainly due to its sensitivity. Bees have been exposed to several concentrations of TiO₂ NPs (1 × 10^-3 , 1 × 10^-4 , 1 × 10^-5 , 1 × 10^-6 mg/10 ml) for 10 days. Morphostructural and histological assays were done on gut and honey sac. The research of exposure biomarkers like metallothioneins 1 (MT1) and Heat Shock Protein 70 (HSP70) was performed to verify if a detoxification mechanism has been activated in the exposed animals. No histological alteration on the epithelium of the gut and honey sac were observed in exposed samples. A significant positivity for anti-MT1 antibody was observed only in the honey sac cells. A weak positivity for HSP70 was observed in both structures analyzed. In several studies have shown the non-toxicity of TiO₂ NPs on other model organisms, in our study, titanium dioxide nanoparticles was proven to be highly toxic at the highest concentration tested (100% of lethality to 1 × 10^-3 mg/10 ml) and moderately toxic at lower concentrations. Honey bees proved to be excellent models for study of NPs toxicity and for monitoring environment.

Biomarkers of Exposure to Chemical Contamination in the Commercial Fish Species Lepidopus caudatus (Euphrasen, 1788): A Particular Focus on Plastic Additives

In recent years, the Mediterranean Sea has become an accumulation zone for waste generated by the 22 countries bordering its shores. Although the effects of plastic litter on the marine environment and on organisms have recently been studied in other areas, further information is needed for the Mediterranean Sea and, in particular, about plastics additives inputs and interactions with the biota and the trophic network, such as phthalates and bisphenol A. Plastic material production, use and disposal contribute also to the release of heavy metals into the environment, such as mercury (Hg), often used during the production of chlorine, the primary ingredient in PVC, lead (Pb) and cadmium (Cd), which are used as stabilizers in PVC and leach out of products during use and disposal. Our research aims to evaluate phthalates, bisphenol A and heavy metals contamination in Lepidopus caudatus (Pisces, Trichiuridae), which could be considered as a potential sentinel species. For the evaluation of toxicological effects, we evaluated the expression of vitellogenin and metallothioneins 1. In all samples analyzed, we have not found microplastics in the gastrointestinal tract but chemical analysis revealed the presence of high content of phthalates, and in particular high quantities of DIDP, DEHP, bis-benzylester phthalate, bis-butyl ester phthalate and mono-N-butyl ester phthalate in different organs. Instead, trace elements detected in tissue revealed a trend of concentrations generally higher in liver and intestine than gill and muscle tissues. Immunohistochemical analysis for anti-metallothionein 1 antibody showed a strong positivity of liver cells, both in females and males. Analysis for the anti-vitellogenin antibody showed in females a strong positivity both in the liver cells and in the gonads, in male specimens was found to be always negative except for a specimen, in which it was highlighted a positivity in some areas of the liver and of the gonad.