Inflammation response and cytotoxic effects in human THP-1 cells of size-fractionated PM10 extracts in a polluted urban site.

To contribute to a greater characterization of the airborne particulate matter's toxicity, size-fractionated PM10 was sampled during different seasons in a polluted urban site in Torino, a northern Italian city. Three main size fractions (PM10 - 3 µm; PM3 - 0.95 µm; PM < 0.95 µm) extracts (organic and aqueous) were assayed with THP-1 cells to evaluate their effects on cell proliferation, LDH activity, TNFα, IL-8 and CYP1A1 expression. The mean PM10 concentrations were statistically different in summer and in winter and the finest fraction PM<0.95 was always higher than the others. Size-fractionated PM10 extracts, sampled in an urban traffic meteorological-chemical station produced size-related toxicological effects in relation to season and particles extraction. The PM summer extracts induced a significant release of LDH compared to winter and produced a size-related effect, with higher values measured with PM10-3. Exposure to size-fractionated PM10 extracts did not induce significant expression of TNFα. IL-8 expression was influenced by exposure to size-fractionated PM10 extracts and statistically significant differences were found between kind of extracts for both seasons. The mean fold increases in CYP1A1 expression were statistically different in summer and in winter; winter fraction extracts produced a size-related effect, in particular for organic samples with higher values measured with PM<0.95 extracts. Our results confirm that the only measure of PM can be misleading for the assessment of air quality moreover we support efforts toward identifying potential effect-based tools (e.g. in vitro test) that could be used in the context of the different monitoring programs.

Feasibility and reliability of a questionnaire for evaluation of the exposure to indoor and outdoor air pollutants, diet and physical activity in 6-8-year-old children.

INTRODUCTION: The MAPEC-Life project aims to study the biological effects of early exposure to air pollutants on the oral mucosa cells of school-age children in five Italian cities. A questionnaire was created to evaluate the association between outdoor and indoor airborne pollutants, lifestyle, diet and biomarker effects. The feasibility and reliability of the questionnaire were evaluated. METHODS: A questionnaire was drawn up to be filled in by the parents of 6-8-year-old children. It consisted of 148 questions on the children's health, physical activity, environmental exposures and the frequency of food consumption at the main meals. First we conducted a questionnaire feasibility study involving 53 volunteer parents. We then performed a reliability study by administering the questionnaire to a further 156 parents and again one month later (test/retest method). The correlations between answers at the first and second administration of the questionnaire were evaluated using the Kappa statistic and Spearman's coefficient. RESULTS: After verifying the feasibility of the questionnaire, we conducted a reliability analysis on 132 completed questionnaires. The percentage of agreement between the first and the second responses given was over 70%, all K values being greater than 0.6. The analysis of calories and macronutrients also showed good agreement. CONCLUSIONS: The questionnaire drawn up for the study proved to be sufficiently reliable for gathering information about the factors of interest in our study of the relationship between air pollution and early biological effects in children.

PM10 in a background urban site: chemical characteristics and biological effects.

PM10 was sampled in a background urban site in Torino, a northern Italian city. PM10 extracts were tested with THP-1 and A-549 cells to evaluate their effects on cell proliferation, LDH activity, TNFα, IL8 and CYP1A1 expression, and genotoxic damage induction (Comet assay). Through Principal Component Analysis (PCA), it was observed that (1) the aqueous extracts induced the inhibition of cell proliferation in the warm season that clustered together to total ions, (2) organic extracts determined a winter cell viability reduction and (3) there was a genotoxic effect associated with PAH and metal concentrations. The analysed low PAH levels were unable to induce significant CYP1A1 expression. The results obtained confirmed that PM composition and seasonality play an important role in particle-induced toxicity. The presence of PM10-induced biological effects at a low polluted site suggested that a reduction of PM10 mass did not seem to be sufficient to reduce its toxicity.

Monitoring air pollution effects on children for supporting public health policy: the protocol of the prospective cohort MAPEC study.

INTRODUCTION: Genotoxic biomarkers have been studied largely in adult population, but few studies so far have investigated them in children exposed to air pollution. Children are a high-risk group as regards the health effects of air pollution and some studies suggest that early exposure during childhood can play an important role in the development of chronic diseases in adulthood. The objective of the project is to evaluate the associations between the concentration of urban air pollutants and biomarkers of early biological effect in children, and to propose a model for estimating the global risk of early biological effects due to air pollutants and other factors in children. METHODS AND ANALYSIS: Two biomarkers of early biological effects, DNA damage by the comet assay and the micronuclei (MN) test, will be investigated in oral mucosa cells of 6-8-year-old children. Concurrently, some toxic airborne pollutants (polycyclic aromatic hydrocarbon (PAH) and nitro-PAH) and in vitro air mutagenicity and toxicity in ultra-fine air particulates (PM0.5) will be evaluated. Furthermore, demographic and socioeconomic variables, other sources of exposures to air pollutants and lifestyle variables will be assessed by a structured questionnaire. The associations between sociodemographic, environmental and other exposure variables and biomarkers of early biological effect using univariate and multivariate models will be analysed. A tentative model for calculating the global absolute risk of having early biological effects caused by air pollution and other variables will be proposed. ETHICS AND DISSEMINATION: The project has been approved by the Ethics Committees of the local Health Authorities. The results will be communicated to local Public Health Agencies, for supporting educational programmes and health policy strategies. LIFE+2012 Environment Policy and Governance. LIFE12 ENV/IT/000614.

Microbiological contamination of digested products from anaerobic co-digestion of bovine manure and agricultural by-products.

AIMS: This study was performed to investigate the microbiological contamination of digestate product (DP) obtained from the anaerobic co-digestion of bovine manure and agricultural by-products. METHODS AND RESULTS: Microbiological analyses were performed on bovine manure, fresh DP, liquid and solid fractions and stored liquid fraction of DP. A statistically significant reduction of faecal bacterial indicator was found after anaerobic digestion except for enterococci. After liquid/solid DP separation, bacteria tend to be concentrated in the solid fraction. Storage does not seem to influence the indicator parameters, except for enterococci. Escherichia coli O157:H7 and Yersinia were not found in any samples analysed. Salmonella was rarely detected in DP samples and its derivates, while Listeria monocytogenes was encountered in many samples. CONCLUSIONS: The results obtained indicate that the hygienic quality of DP is for almost all microbiological parameters better than that of the bovine manure (range of reduction 1.6-3.1 log10) and suggest the need to identify specific pathogen indicators related to the hygienic characteristics of DPs. SIGNIFICANCE AND IMPACT OF THE STUDY: This study highlights that the anaerobic co-digestion of bovine manure and agricultural by-products in a field-scale biogas plant does not increase human health risk with respect to the use of animal manure for agricultural fertilization.