Exploring pH levels and environmental impacts on handwash products in Riyadh, Saudi Arabia: A cross-sectional study

Abstract

ABSTRACT Background: The human skin, with a pH of 4 to 6, serves as a barrier against external pathogens. Alkaline handwash products (HWPs) can compromise this barrier and are widely used following the Coronavirus disease-2019 (COVID-19) pandemic. This study aims to determine the pH of a sample of HWPs in Riyadh, Saudi Arabia, and assess the effect of environmental factors on their pH. Methods: This is a cross-sectional, descriptive, observational study carried out in Riyadh, Saudi Arabia. The study involved a convenience sample of 33 liquid soaps, soap bars, and synthetic detergents (Syndets) from various brands. The pH of the handwash products was measured using laboratory-validated techniques. Data analysis was conducted using RStudio 2022 software. Results: Of the HWPs, 16 (48.5%) had a highly alkaline pH (≥10), while 14 (42.4%) had an acidic pH (4.0-6.9). Most liquid soaps were acidic (84.6%), with a mean pH of 5.9, whereas soap bars had a mean pH of 10.3. Syndets had a mean pH of 6.0. Conclusions: On average, liquid soaps and syndets offered a more physiological pH than soap bars. Liquid soaps were more affordable than synthetic detergents, making them a better value option among the three types of HWPs. Environmental factors such as exposure to hot weather did not have a significant impact on HWPs.