Volatile organic compounds (VOCs) are released to the indoor air of retail stores from numerous products and activities, but available literature lacks a systematic understanding of the variability of VOC concentrations. In this study, we measured concentrations of total VOCs (TVOC) in 32 retail stores using a high-sensitivity photoionization detector (PID). Indoor thermal comfort parameters, including temperature, relative humidity, and air velocity, were simultaneously measured using an anemometer. The store-level TVOC concentrations ranged from 30 to 869 ppb and exceeded the LEED guideline in 31 stores. TVOC levels were notably high in hardware stores (median = 536 ppb, p = 0.0002) and paints, household, and home accessories sections within stores (p < 0.05). TVOC levels were elevated in mornings and evenings, possibly due to low ventilation and cleaning activities at the beginning and end of business hours. The between-store, within-store, and temporal variations accounted for 85%, 0.5%, and 14% of the total variance, respectively. The variance structure suggested that in-store VOC concentrations were predominantly driven by their source location, and representative monitoring should first consider covering various store types. Current store VOC levels present health concerns, but further studies are needed to evaluate risks among customers.

Passive sampling for airborne volatile organic compounds (VOCs) has gained popularity; however, diffusive uptake rates (URs) have been experimentally determined for only a small subset of VOCs. This study aims to develop empirical models that can interpolate effective URs (UR_eff) for a wide range of VOCs. The modelling was based on the standard automated thermal desorption (ATD) tubes packed with Tenax TA and targeted the sampling efficiency (α), defined as the ratio between the ideal UR (UR_ideal) and UR_eff. Available experimentally determined URs were compiled from literature. Method detection limits were determined on a thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS) system. The 8-h UR_eff can be modeled with retention volumes or boiling points (BPs) and the biases were within ±20%. The α for 7-day UR_eff can be estimated by the model: α = 0.3626 Ln(BP) − 1.2324. The 8-h and 7-day UR_eff values were then compiled for 75 VOCs commonly encountered in the environmental and occupational settings. The TD analytical method showed high precision, linearity and sensitivity, suitable for measuring indoor and outdoor VOCs. The approach and data presented here are anticipated to ease passive monitoring of VOCs for the general users.

The lockdowns due to the COVID-19 pandemic have been reported to reduce ambient air pollution in many cities globally. This study aims to examine whether air pollution dropped in Memphis, a typical U.S. metropolitan city and transportation hub, during the lockdown from 25 March to 4 May, 2020. Daily air pollution data measured at five representative monitoring stations in the Memphis Metropolitan Area were downloaded from the U.S. Environmental Protection Agency’s Air Quality System. The mean concentrations of fine particulate matter (PM_2.5), nitrogen dioxide (NO₂), and ozone during the lockdown were compared with the baseline concentrations measured during the same periods in 2017–2019 using linear regression models. The average vehicle miles traveled (VMT) reduced by 57% in this region during the lockdown compared to that during 1–24 March, 2020. The mean (± standard deviation) concentrations of PM_2.5, NO₂, and ozone were 7.5 ± 2.6 μg/m³, 16.5 ± 9.4 ppb, and 44.5 ± 8.4 ppb, respectively, during the lockdown. They did not statistically differ from the baseline concentrations, nor were they lower than the mean concentrations in the prior month (25 February–24 March, 2020), after accounting for meteorological conditions. The lack of effect could be explained by the small contribution of traffic emissions to air pollution. The results suggest that the “stay-at-home” order had an insignificant impact on reducing air pollution in Memphis.

The implications of environmental contamination on human health in the Niger Delta region of Nigeria remain a topic of growing international public health interest. To better understand ongoing air pollution and initiate remediation efforts, the United Nations Environmental Programme (UNEP) report recommended the monitoring of volatile organic compounds (VOCs) across different media (water, soil, and air) in Ogoniland, an at-risk population in the Niger Delta region of Nigeria. In this pilot study, we measured indoor VOC concentrations in the indoor air of 20 households in Ogale, an Ogoniland community whose groundwater system is contaminated with benzene at levels 900 times the World Health Organization guidelines and evaluated self-reported health conditions and predicted cancer risks and hazards from inhalation exposure to VOCs. We detected higher concentrations of benzene (mean = 25.7 μg/m³, SD = 23.2 μg/m³) and naphthalene (mean = 7.6 μg/m³, SD = 13.8 μg/m³) than has been reported in other regions. Although study participants reported health symptoms consistent with VOC exposure, we were underpowered to detect a significant association between select indoor VOCs and these self-reported health symptoms using univariate logistic regression models. These findings suggest that that the health symptoms reported by participants may be poor proxies for the underlying disease processes associated with adverse health outcomes due to VOC exposure in this community and that the burden of adverse health effects due to VOC exposure may stem from the contaminated groundwater system. We estimated a non-cancer hazard quotient of 3 from exposure to naphthalene and lifetime excess cancer risks from exposure to naphthalene, benzene, p-dichlorobenzene, carbon tetrachloride, and ethylbenzene of 3 × 10⁻⁴, 2 × 10⁻⁴, 6 × 10⁻⁵, 6 × 10⁻⁶, and 1 × 10⁻⁵, respectively. These results exceed common risk benchmarks in the United States, suggesting a need for further studies to characterize VOC exposures, sources, and associated health risks in the Niger Delta.