de Angelis, Cristina (2020) The environment and male fertility: observational study evaluating semen quality in a large cohort of young men living in the land of fires. [Tesi di dottorato]

Anteprima

Testo de_angelis_cristina_32.pdf Download (1MB) | Anteprima

Abstract

Campania Region has been characterized by a waste management crisis since 1980, resulting in the largely documented illegal disposal of urban, toxic and industrial waste, and diffuse practice of illegal waste burning set up by residents, which by time determined a significant increase in local environmental pressure. Despite mounting media attention and pervasive concern among residents in regards of potential waste exposure-induced health problems, no large investigations have been performed so far, addressing semen quality of young men living within the “Land of “Fires” (LF), and/or the potential implication of heavy metals burden, quantitatively determined in a large number of semen samples. The aim of the current research study was to bridge the existing gap of information concerning semen quality of men living in the high environmental pressure area of the LF, and to investigate the potential association between non-occupational exposure to non-essential trace elements, particularly cadmium (Cd), and seminal parameters, by evaluating a large cohort of healthy men with at least 10 years of residence within the LF, exhaustively controlled for potential confounders. The study included two different cohorts of subjects, recruited within two awareness and prevention campaigns on infertility and testis cancer in high environmental impact (HI) areas, identified on the basis of the Campania Region Environmental Protection Agency (ARPAC) reports. Within the first cohort (C1), 730 participants were enrolled: 544 healthy males from HI areas belonging to the LF, and 186 healthy males resident in a low environmental impact (LI) area not belonging to the LF. Within the second cohort (C2) 512 participants were enrolled, resident in the HI municipalities of Acerra (N=197), Afragola (N=117), and Giugliano in Campania (N=162), belonging to the LF. Participants were interviewed on medical history and underwent a complete physical examination including evaluation of anthropometric characteristics, urogenital examination, and scrotal and prostate transrectal ultrasonography, and semen analysis according to the 2010 World Health Organization laboratory manual guidelines. Trace elements quantitative determination by ICP-MS was performed in serum and semen of C2. The current research study on clinically healthy young men of reproductive age, non-occupationally exposed to toxic chemicals, demonstrated that seminal parameters of men who had lived for at least 10 years within HI areas of Campania Region, did not differ from age- and BMI-matched controls from LI areas with similar anthropometric characteristics, dietary habits, and physical activity. Moreover, no difference in the prevalence of below-reference values for any seminal parameter was detected. The current study also demonstrated that Cd, a known reproductive toxicant, might be detected in semen at significantly higher concentrations than serum, suggesting that seminal Cd determination might serve as a sensitive earlier marker of exposure, particularly in non-occupationally exposed men, and that semen Cd did nor correlate to serum Cd, therefore confirming the widely accepted notion that Cd specifically accumulates within the human testis, and more precisely mirrors local testicular exposure. Noteworthy, semen Cd, but not serum Cd burden, was negatively correlated to sperm concentration and sperm total count and this finding was consistent across different statistical modeling strategies, therefore supporting the assumption that even micro-doses of metal may have effects on semen quality. Concurrent factors potentially implicated in semen Cd burden might be snatched from additional observations deriving from the current study, including the potential presence of isolated sources of Cd in specific areas within the HI target of the study, or the potential contribution of the balance between seminal concentrations of essential and non-essential trace elements to the individual susceptibility to Cd accumulation within the testis.

Downloads

Actions (login required)

Modifica documento