Male fertility is progressively declining in many developed countries, but the relationship between male infertility and environmental factors is still unclear.To assess the influence of environmental temperature and air pollution on semen parameters, using a big-data approach.A big data analysis of parameters related to 5131 men, living in a province of Northern Italy and undergoing semen analyses between January 2010 and March 2016 was performed. Ambient temperature was recorded on the day of analysis and the 90 days prior to the analysis and the average value of particulate matter (PM) and NO2 in the year of the test. All data were acquired by geocoding patients residential address. A data warehouse containing 990,904,591 data was generated and analysed by multiple regressions.5573 semen analyses were collected. Both maximum and minimum temperatures registered on the day of collection were inversely related to total sperm number (p < .001), non-progressive motility (NPrM) (p < .005) and normal forms (p < .001). Results were confirmed considering temperature in the 30 and 60 days before collection, but not in the 90 days before collection. Total sperm number was lower in summer/autumn (p < .001) and was inversely related with daylight duration (p < .001). PM10 and PM2.5 were inversely related to PrM (p < .001 and p < .005) and abnormal forms (p < .001).This is the first evaluation of the relationship between male fertility-related parameters and environment using a big-data approach. A seasonal change in semen parameters was found, with a fluctuation related to both temperature and daylight duration. A negative correlation between air pollution and semen quality is suggested. Such seasonal and environmental associations should be considered when assessing changes of male fertility-related parameters over time.

Passive air samplers (PAS) have become recurrent methods for environmental monitoring. However, the influence of environmental variables, such as temperature, over these devices has not been fully investigated. Since climate change is likely to induce major environmental changes, the role of the temperature needs to be studied to assure the suitability of PAS for the long-term monitoring of semi-volatile organic compounds (SVOCs) and their utility to compare data from different locations. This study aimed at evaluating the potential loss of polycyclic aromatic hydrocarbons (PAHs) in PAS containing disks of polyurethane foam (PUF) at different temperatures. The gradient of temperature inside and outside the PAS was firstly determined, being noted an internal/external difference of up to 5 °C. Secondly, a lab-controlled experiment was performed by daily analyzing PAHs in PUF-based PAS exposed to 25 °C and 38 °C, for a period of 7 days. A significant loss of PAHs in PUFs was not observed for any of both scenarios, remaining constant through time. Moreover, PAH levels were not significantly different according to the temperature. These findings indicate that the environmental temperature does not affect the stability of PAHs in PAS. Once PAHs have been uptaken, they are not easily volatilized from these devices. Consequently, PAS are good environmental monitors independently on the ambient conditions of temperature, being suitable for the comparability of data, either temporally or spatially, on the airborne concentrations of PAHs.