Effect of a smartphone-based educational toolkit on behavioural outcomes in personal care product use: a randomized controlled trial

Abstract

Aim: In 2023, the average woman used 13 different personal care products (PCPs) daily, exposing them to 114 different chemical toxins, including carcinogens, synthetic preservatives, and fragrances. Parabens, commonly used as preservatives and fragrance ingredients, are found in household and PCPs, such as cosmetics and hair products. Exposure to parabens has been associated with an increased risk of breast cancer and endocrine disorders. This study aims to evaluate the effectiveness of the “Paraben-Free & Me” educational toolkit (OSF Registration DOI: 10.17605/OSF.IO/WXU34) by exploring whether it influences changes of 3.5 points (10%) in paraben-free behaviour in women aged 18–35 years old when compared to the control group.

Methods: This study consists of a randomized controlled trial to evaluate the effectiveness of the educational toolkit among 101 female students aged 18 to 35 years old following a four-week intervention period. Baseline and follow-up questionnaires were used to assess participants’ knowledge and access to information, risk perception, health beliefs, and paraben-free behaviour by providing composite scores for each construct.

Results: The change in the knowledge and access to information score was significantly greater in the intervention group compared to the control group (+3.96, 95% CI [1.95, 5.96]). There were slight differences between groups in relation to health beliefs (+0.63, 95% CI [–1.02, 2.27]), risk perception (+0.96, 95% CI [–0.61, 2.54]), and paraben-free behaviour (–0.16, 95% CI [–2.88, 2.57]); however, these were not statistically significant.

Conclusions: This study suggests that while the “Paraben-Free & Me” educational toolkit was unsuccessful in promoting greater paraben-free behaviour in the intervention group, it can increase women’s knowledge and access to information related to parabens in their PCPs. Future studies can focus on evaluating paraben-free behaviour and the effectiveness of the educational toolkit by exploring biological measures, such as urinary concentrations of parabens, and air pollutant concentrations.

Keywords

parabens / exposure / educational toolkit / behaviour

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