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Household cleaning products improve domestic cleanliness but they can have a negative impact on indoor air quality and the wide range of chemicals used in them may have adverse effects on respiratory health, especially in children.

The Chinese University of Hong Kong (CUHK) conducted Asia’s first comprehensive epidemiological study investigating health impacts of household cleaning products on children with rhinitis. The study investigated the use of cleaning products and their association with rhinitis among primary school children in Hong Kong. The results show that frequent use of chemical cleaning products at home almost doubles the risk of triggering childhood rhinitis. The findings have been published online in the leading medical journal – Journal of Allergy and Clinical Immunology ^[1]. 

Frequent use of household cleaning products may increase the risk of triggering rhinitis in children by 29%-97% 

In 2012/2013, a research team led by Dr. Xiang Qian LAO, Assistant Professor, The Jockey Club School of Public Health and Primary Care (JCSPHPC), Faculty of Medicine at CUHK commenced a three-year longitudinal study to investigate health impacts of household cleaning products on the respiratory health of primary school children in Hong Kong. This was funded by the Health and Medical Research Fund of the Food and Health Bureau and the General Research Fund of the University Grants Committee. 

Researchers surveyed a total of 2,299 students from 21 primary schools representing a wide geographical coverage in Hong Kong. Questionnaires were used to collect information on the usage of household cleaning products at the students’ homes, including the weekly frequency, duration of each use and the chemical cleaning products they were exposed to. The collected data was then used to calculate the cumulative time of exposure to chemical cleaning products of the students. 

The students were then grouped into tertiles, based on the cumulative time of exposure. Compared to the students within the lowest tertile (cumulative time less than 2.4 hours per week), students within the highest tertile (cumulative time more than 3.2 hours per week) had an increased risk of 29%, 97% and 67% for occasional, frequent, and persistent rhinitis respectively after controlling a wide range of confounders. Every one hour increment of usage time was associated with an increased risk of 2.1%, 3.6% and 1.2% for occasional, frequent, and persistent rhinitis in children. However, there were no such associations observed if clean water was used for daily household cleaning. 

According to the function of the cleaning products, they were categorized into 13 types. The top three types of highest exposure were kitchen cleaners, floor cleaners and bathroom cleaners. The research team also examined whether a single type of chemical product had dominant health effects. Result suggested that the effect should be due to the total exposure to all or several types of the cleaning products. 

Parents are recommended to reduce children’s exposure to chemical cleaning products 

Rhinitis is a common respiratory disease in children. According to the recent study data, around 50% of children are suffering from the condition. Symptoms of Rhinitis include stuffy nose, sneezing, running nose and itching eyes. It may impair the quality of the children’s life as well as their school performance. Because household cleaning products are commonly used in people’s daily lives, their health impacts are an important issue in public health. 

Dr. LAO stated, ‘The recent findings suggest that it is necessary to develop healthier cleaning products. Parents are also recommended to prevent triggering rhinitis in children by reducing their exposure to chemical cleaning products at home.’ 

Suggestions include:  

1) Use fewer (including frequency and duration) chemical cleaning products and avoid abuse;
2) Conduct thorough cleanings when children are not at home; and
3) Maintain sufficient ventilation during the use of household cleaning products

JCSPHPC will continue further studies in the relationship between the use of household cleaning products and respiratory health of children, which may hopefully provide more relevant information and recommendations to the public in the future. 

^[1]Click this link for the full text of the research findings:
http://www.jacionline.org/article/S0091-6749(16)30254-8/fulltext