Study question: Could pollution exposure play a key role on sperm quality, interms of DNA fragmentation index (DFI)?Summary answer: Patients exposed to high level of pollution show an higherpercentage of sperm DNA fragmentation index in contrast with patient fromcontrol group.What is known already: Taranto area is characterized by a number of steelfactories and petrochemical industries. Data about the detrimental effects of environmentalpollution are alarming. Pollution coming from the industrial plantscauses health and fertility risks, mainly due to the exposure to several pollutant(PM10, heavy metals, etc).Toxic substances can affect DNA directly or indirectly, through oxidativestress, impairing sperm quality: high levels of sperm DNA fragmentation indexhas been summoned as possible cause of male infertility; it is known, in effect,that a spermatic DFI less than 15% is physiologic, while above 30% is relatedto fertility issues.Study design, size, duration: Case-control study: valuation of DFI in patientsexposed to different level of environmental pollutants.A. Patients from the city of Taranto leaving far from industriesB. Patients working in local steel factories in TarantoC. Patients from Palermo (control group)Duration of the study: 24 months, from January 2010 to December 2012.DFI assessed by in situ TUNEL assay. The fields of fixed semen sampleswere analysed, by fluorescence and light microscopy. Participants/materials, setting, methods: Three different groups of patients(tot. number of pts 152), afferent to an assisted reproduction clinic in Taranto:Group A) workers of local steel factories (pt. No: 28) and B) Taranto residents(pt. No: 61) and a Control group C) (pt. No: 63) afferent to an assisted reproductionclinic in Palermo with supposed fertility issues.Main results and the role of chance: Our study analyzed sperm samples fromthree patients groups: A) workers of local steel factories; B) Taranto residents;C) Controls.We observed a highly statistically significant increase of spermatic DNAfragmentation Index (DFI) in the “factory workers” group, constantly exposedto environmental pollutants for professional reasons” compared with control(DFI 31% vs 16.8% P ≤ 2.685 * 10−6) as well as in comparison with the Tarantoresident (DFI 31% vs 25% P ≤ 2.9 * 10−3). We have also observed a statisticallysignificant difference between Taranto resident and control group (DFI 25% vs16.8% P ≤ 3.681*10−6).Limitations, reasons for caution: The limitation of this study is that it is aretrospective study and the size of cohort of patients.Wider implications of the findings: Our study supports the hypothesis thatthe level of dioxin exposition might be positively correlated with the spermDFI.Interrupting the sperms damaging source might bring back the DFI levelto normal values. So, moving away from the damaging source, patients from Aand B groups could restore spermatogenesis.Trial registration number: The trial is an observational study and no registrationis needed.
|Numero di pagine||1|
|Stato di pubblicazione||Published - 2016|