Oral exposure to hazardous substances is not often addressed during risk assessments, but a new review and analysis highlights that it may be relevant in many workplaces.
Researchers at Germany's Federal Institute for Occupational Safety and Health undertook a systemic literature review and meta-analysis to investigate the relevance of unintentional oral exposure to hazardous substances and concluded that it can contribute significantly to total worker exposure and must be considered when conducting risk assessments.
The researchers sought to understand how often relevant behaviours (for example, hand to face contact) occurs in adults, and how often relevant occupational hygiene practices and measures (for example, hand washing) are performed in the workplace.
Secondary questions arose during the study, including – does regular training improve worker compliance with good occupational hygiene practice, and is it possible to consciously avoid behaviours that contribute to oral exposure.
The review looked at studies covering a range of different workplaces, including offices, healthcare site, industrial sites, lead refineries, e-waste recycling.
The analysis showed that workers across a wide range of industries are exposed to hazardous substances from touching their mouths, on average 17 times per hour. This behaviour may be intensified by emotionally and cognitively demanding situations.
Hazardous substances in the workplace frequently deposit on faces and under fingernails. The frequency of workers’ hands contacting their mouths is influenced by several factors including personal habits such as biting fingernails, stress, anxiety and nervousness.
Being aware of the hazards of occupational substances was associated with reduced contact, however training on behaviours or general occupational hygiene practices only has a small influence over hand-face contact frequency.
Regardless of PPE requirements and work processes, regular hand washing is an important part of staying safe at work. Making regular hand hygiene an unconscious habit through repetition is the smart approach to reducing oral exposure to hazardous substances in the workplace.