We reviewed available evidence in medical literature concerning experimental models of exposure to ionizing radiations (IR) and their mechanisms of producing damages on living organisms. The traditional model is based on the theory of “stochastic breakage” of one or both strands of the DNA double helix. According to this model, high doses may cause the breaks, potentially lethal to the cell by damaging both DNA strands, while low doses of IR would cause essentially single strands breaks, easily repairable, resulting in no permanent damages. The available evidence makes this classical model increasingly less acceptable, because the exposure to low doses of IR seems to have carcinogenic effects, even after years or decades, both in the exposed individuals and in subsequent generations. In addition, the cells that survived the exposure to low doses, despite being apparently normal, accumulate damages that become evident in their progeny, such as nonclonal chromosomal aberrations, which can be found even in cells not directly irradiated due to the exchange of molecular signals and complex tissue reactions involving neighboring or distant cells. For all these reasons, a paradigm shift is needed, based on evidence and epigenetics.
Wildlife has often presented and suggested the effects of endocrine disrupting chemicals (EDCs). Animal studies have given us an important opportunity to understand the mechanisms of action of many chemicals on the endocrine system and on neurodevelopment and behaviour, and to evaluate the effects of doses, time and duration of exposure. Although results are sometimes conflicting because of confounding factors, epidemiological studies in humans suggest effects of EDCs on prenatal growth, thyroid function, glucose metabolism and obesity, puberty, fertility, and on carcinogenesis mainly through epigenetic mechanisms. This manuscript reviews the reports of a multidisciplinary national meeting on this topic.
Background: Cancer Registries (CRs) remain the gold standard for providing official epidemiological estimations. However, due to CRs' partial population coverage, hospitalization records might represent a valuable tool to provide additional information on cancer occurrence and expenditures at national/regional level for research purposes. The Epidemiology of Cancer in Italy (EPIKIT) study group has been built up, within the framework of the Civic Observers for Health and Environment: Initiative of Responsibility and Sustainability (COHEIRS) project under the auspices of the Europe for Citizens Program, to assess population health indicators. Objective: To assess the burden of all cancers in Italian children and adults. Methods: We analyzed National Hospitalization Records from 2001 to 2011. Based on social security numbers (anonymously treated), we have excluded from our analyses all re-hospitalizations of the same patients (n = 1,878,109) over the entire 11-year period in order to minimize the overlap between prevalent and incident cancer cases. To be more conservative, only data concerning the last five years (2007-2011) have been taken into account for final analyses. The absolute number of hospitalizations and standardized hospitalization rates (SHR) were computed for each Italian province by sex and age-groups (0-19 and 20-49). Results: The EPIKIT database included a total of 4,113,169 first hospital admissions due to main diagnoses of all tumors. The annual average number of hospital admissions due to cancer in Italy has been computed in 2362 and 43,141 hospitalizations in pediatric patients (0-19 years old) and adults (20-49 years old), respectively. Women accounted for the majority of cancer cases in adults aged 20-49. As expected, the big city of Rome presented the highest average annual number of pediatric cancers (n = 392, SHR = 9.9), followed by Naples (n = 378; SHR = 9.9) and Milan (n = 212; SHR = 7.3). However, when we look at SHR, minor cities (i.e., Imperia, Isernia and others) presented values >10 per 100,000, with only 10 or 20 cases per year. Similar figures are shown also for young adults aged 20-49. Conclusions: In addition to SHR, the absolute number of incident cancer cases represents a crucial piece of information for planning adequate healthcare services and assessing social alarm phenomena. Our findings call for specific risk assessment programs at local level (involving CRs) to search for causal relations with environmental exposures.
NDs are a collection of disorders that appear in the early stages of development and are variously associated with cognitive and behavioral dysfunctions. The strong heritability of these conditions (in particular autism and schizophrenia) argues in favor of a genetic origin. On the other hand, the massive increase in NDs implies a preponderant role of environmental factors and epigenetic mechanism (Panisi et al. 2021).
