The effects of exposure to different levels of ionising radiation were assessed on the genetic, epigenetic and microbiome characteristics of the “hologenome” of earthworms collected at sites within the Chernobyl exclusion zone (CEZ). The earthworms Aporrectodea caliginosa (Savigny, 1826) and Octolasion lacteum (Örley, 1881) were the two species that were most frequently found at visited sites, however, only O. lacteum was present at sufficient number across different exposure levels to enable comparative hologenome analysis. The identification of morphotype O. lacteum as a probable single clade was established using a combination of mitochondrial (cytochrome oxidase I) and nuclear genome (Amplified Fragment Length Polymorphism (AFLP) using MspI loci). No clear site associated differences in population genetic structure was found between populations using the AFLP marker loci. Further, no relationship between ionising radiation exposure levels and the percentage of methylated loci or pattern of distribution of DNA methylation marks was found. Microbiome structure was clearly site dependent, with gut microbiome community structure and diversity being systematically associated with calculated site-specific earthworm dose rates. There was, however, also co-correlation between earthworm dose rates and other soil properties, notably soil pH; a property known to affect soil bacterial community structure. Such co-correlation means that it is not possible to attribute microbiome changes unequivocally to radionuclide exposure. A better understanding of the relationship between radionuclide exposure soil properties and their interactions on bacterial microbiome community response is, therefore, needed to establish whether these the observed microbiome changes are attributed directly to radiation exposure, other soil properties or to an interaction between multiple variables at sites within the CEZ.

Genetic and epigenetic changes were investigated in chronically irradiated Scots pine (Pinus sylvestris L.) populations from territories that were heavily contaminated by radionuclides as result of the Chernobyl Nuclear Power Plant accident. In comparison to the reference site, the genetic diversity revealed by electrophoretic mobility of AFLPs was found to be significantly higher at the radioactively contaminated areas. In addition, the genome of pine trees was significantly hypermethylated at 4 of the 7 affected sites.

In this report, the toxic effect of TCE (trichloroethylene), PCE (tetrachloroethylene), and potassium dichromate on P. subcapitata was investigated. The test was conducted at different concentrations of pollutants, starting from the European Community limit values defined for each analysed contaminant. Mixtures of pollutants were also tested to verify the combined effect of algae cells. Results suggest that both TCE and PCE were able to reduce P. subcapitata growth and metabolism starting from 0.05 and 0.02 mg L⁻¹ of contaminant, respectively. PCE seems to be substantially more toxic than TCE. Chromium produces a clear effect on algae growth and esterase activity only starting from 1 mg L⁻¹ of potassium dichromate; this result confirms the suitability of EU limit value. AFLP analysis showed that all tested pollutants produce DNA mutations probably due to oxygen radicals. Generally, chromium, at high concentrations, is more toxic and genotoxic that TCE or PCE. Test performed with a mixture of pollutants showed a synergic effect of chromium and organic compounds suggesting that the membrane damage induced from organic substances should increase the chromium cellular access.

A number of compounds found in particulate matter with an aerodynamic diameter <2.5 (PM2.5) can interact with DNA either directly or after enzymatic transformation to induce DNA modifications. These particulate matter (PM)-induced alterations in DNA may be associated with increased frequencies of pollution-associated diseases, such as lung cancer. In the present study, we applied different methods to assess the mutagenicity and genotoxicity of monthly PM2.5 organic extracts collected over a full year. We used the Salmonella assay, exposed cultured human embryonic lung fibroblasts and applied extracellular lactate dehydrogenase (LDH) and 2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxyanilide inner salt (XTT) assays to assess the cytotoxicity of PM2.5 on the cells. We assessed both the expression levels of a number of DNA repair genes (using qRT-qPCR) and the genetic profile of the treated cells compared to the control. The expression levels of XRCC1 and APE1, which are involved in the first steps of base excision repair, as well as ERCC1, XPA and XPF, which encode nucleotide excision repair subunits, were analysed. The monthly mean of the PM2.5 collected was 35.16 ± 22.06 μg/m³. The mutagenicity of PM2.5 to TA98 was 46 ± 50 net revertants/m³, while the mutagenicity to TA98 + S9 was 17 ± 19 net revertants/m³. The mean IC₅₀values were 2.741 ± 1.414 and 3.219 ± 2.764 m³of equivalent air in the XTT and LDH assays, respectively. A marked and significant increase in APE1 expression levels was observed in the exposed cells. This effect was also significantly correlated with mutagenicity (p < 0.01). No induced AFLP fragment profile alterations were detected. The proposed approach seems to be useful for integrated evaluation and for highlighting the mechanisms inducing DNA damage.

In this study, Hypnum cupressiforme moss bags were used to examine the atmospheric deposition of trace elements in the oil refinery region of Sardinia (Italy) compared with surrounding natural zones. The concentrations of 13 elements [arsenic (As), calcium (Ca), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), sodium (Na), nickel (Ni), lead (Pb), vanadium (V), and zinc (Zn)] were determined using inductively coupled plasma optical emission spectrometry. A significant accumulation of pollutants was detected using active biomonitoring with moss bags compared with a control site. The most relevant contaminants for all of the tested sites were Cr, Cu, Ni, and Zn. Moreover, the accumulation of Cr and Zn in the refinery industrial areas, IA1 and IA2, was more than five times greater than that detected at the control site. Levels of Cd, Mg, and Pb were also higher at all of the monitored sites compared with the control site. Both genomic and proteomic methods were used to study the response of H. cupressiforme to air pollution. No DNA damage or mutations were detected using the amplified fragment length polymorphisms (AFLP) method. At the protein level, 15 gel spots exhibited differential expression profiles between the moss samples collected at the IA1 site and the control site. Furthermore, among the 14 spots that showed a decrease in protein expression, nine were associated with ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and proteins of the light-harvesting complexes of photosystem (PS) II, three were associated with protein synthesis, and three were stress-related proteins. Thus, some of these proteins may represent good moss biosensors which could be used as pre-alert markers of environmental pollution.