Abstract:

The production environment of traditional mining and metallurgy industry is abominable, and there is a lot of dust and heavy metal pollution which is a serious threat to the skin health of front-line workers. At present, little attention has been paid to the skin cleaning of mining and metallurgy workers, and there are few relevant products in the market. In this study, by adding microbial inactivated spores to the soaps, the effects of different amounts of spores on the detergency of cleaning soaps were studied. The similarities and differences of dust removal and heavy metal removal between diatomite, activated carbon and spore-added soaps were compared. The effects of these three kinds of soaps on skin cleaning were tested by sensory evaluation. The results show that the addition of diatomite can achieve a dust removal rate of 80%. Although activated carbon has high specific surface area, its fine particles are also easy to be adsorbed in the texture of the palm, causing secondary pollution. Therefore, the removal rate of activated carbon is the lowest. Adding 1% （w/w） inactivated spores to the soap base can remove 95% of the dust pollution, and the removal rate of heavy metals can be increased from 90% to more than 95% by secondary washing. In the sensory evaluation, the palm of the hand after being washed is still not clean enough because of the adsorption of black activated carbon, and the impression is the worst; the cleaning effect of diatomite soap is close to that of daily household soap, and the impression is in the middle; the cleaning effect of spore-added soap has the most obvious cleaning effect, and the impression is the best. There are various functional groups on the microbial spore wall, such as amino acid residues, lipids and proteins, which may play an important role in the cleaning of heavy metals. In conclusion, a cleaning soap for mining dust based on microbial inactivated spores was developed, which could provide deep skin cleaning and effective removal of heavy metals and provide protection for skin health of workers in mining and metallurgy.

Key words: mining and metallurgy, dust, spore, cleaning soap, heavy metal, skin