Effect of short-term exposure to air pollution on COVID-19 mortality and morbidity in Iranian cities.

Purpose: The association between air pollutant (PM, PM, NO, and O) concentrations and daily number of COVID-19 confirmed cases and related deaths were evaluated in three major Iranian cities (Tehran, Mashhad, and Tabriz).

Methods: Hourly concentrations of air pollutants and daily number of PCR-confirmed cases and deaths of COVID-19 were acquired (February 20, 2020 to January 4, 2021). A generalized additive model (GAM) assuming a quasi-Poisson distribution was used to model the associations in each city up to lag-day 7 (for mortality) and 14 (for morbidity).

The detection of SARS-CoV-2 RNA in indoor air of dental clinics during the COVID-19 pandemic.

In the indoor environment of dental clinics, dental personnel and patients are exposed to a risk of infection because of the transmission of SARS-CoV-2 via particles or droplets. This study investigated the presence of SARS-CoV-2 RNA in indoor air of dental clinics in Tehran, Iran. Air sampling was done (n = 36) collecting particulate samples on PTFE filters at flow rates of 30 to 58 L/min.

Presence of SARS-CoV-2 in the air of public places and transportation.

This study investigated the presence of SARS-CoV-2 in air of public places such as shopping centers, a post office, banks, governmental offices, and public transportation facilities including an airport, subways, and buses in Tehran, Iran. A total of 28 air samples were collected from the eight groups of public and transportation locations. The airborne particle samples were collected on PTFE or glass fiber filters using two types of samplers with flow rates of 40 and 3.

Exposure to BTEX in beauty salons: biomonitoring, urinary excretion, clinical symptoms, and health risk assessments.

Benzene, toluene, ethylbenzene, and xylene (BTEX) concentrations were measured in beauty salons (BS) and in the urine of the beauty practitioners and a control group. Indoor and outdoor concentrations of BTEX were measured in 36 randomly selected salons. Before- and after-shift urinary BTEX were measured from one female non-smoker employee in each salon, and repeated three times.