Impact of SARS-CoV-2 lockdown and de-escalation on air-quality parameters.

The SARS-CoV-2 health crisis has temporarily forced the lockdown of entire countries. This work reports the short-term effects on air quality of such unprecedented paralysis of industry and transport in different continental cities in Spain, one of the countries most affected by the virus and with the hardest confinement measures. The study takes into account sites with different sizes and diverse emission sources, such as traffic, residential or industrial emissions.

Secondary organic aerosol formation from styrene photolysis and photooxidation with hydroxyl radicals.

The formation of secondary organic aerosol (SOA) generated by irradiating styrene in the presence and/or absence of OH, NOx, HO vapour and seed aerosol has been investigated for the first time. Experiments were conducted in a smog chamber at 298 K and atmospheric pressure. Styrene decay was measured by gas chromatography with a mass spectrometric detector (GC-MS), and the temporal evolution of the aerosol was monitored using a fast mobility particle sizer (FMPS).

Assessment of chemical and microbiological parameters of indoor swimming pool atmosphere using multiple comparisons.

The aim of this study was to evaluate the air quality of an indoor swimming pool, analyzing diurnal and seasonal variations in microbiological counts and chemical parameters. The results indicated that yeast and bacteria counts, as well as carbon dioxide (CO ), nitrogen oxides (NO ) and O concentrations, showed significant diurnal difference. On the other hand, temperature, relative humidity (R.