The incidence of occupational injuries and diseases associated with industrialization has declined markedly following developments in science and technology, such as engineering controls, protective equipment, safer machinery and processes, and greater adherence to regulations and labor inspections. Although the introduction of health and safety management systems has further decreased the incidence of occupational injuries and diseases, these systems are not effective unless accompanied by a positive safety culture in the workplace. The characteristics of work in the 21(st) century have given rise to new issues related to workers' health, such as new types of work-related disorders, noncommunicable diseases, and inequality in the availability of occupational health services. Overcoming these new and emerging issues requires a culture of prevention at the national level. The present paper addresses: (1) how to change safety cultures in both theory and practice at the level of the workplace; and (2) the role of prevention culture at the national level.

The mechanisms by which iron is absorbed are similar to those of divalent metals, particularly manganese, lead, and cadmium. These metals, however, show different toxicokinetics in relation to menarche or menopause, although their interaction with iron is the same. This review focuses on the kinetics of these three toxic metals (manganese, lead, and cadmium) in relation to menarche, pregnancy, and menopause. The iron-manganese interaction is the major factor determining sex-specific differences in blood manganese levels throughout the whole life cycle. The effects of estrogen overshadow the association between iron deficiency and increased blood lead concentrations, explaining why women, despite having lower ferritin concentrations, have lower blood lead concentrations than men. Iron deficiency is associated with elevated cadmium levels in premenopausal women, but not in postmenopausal women or men; these findings indicate that sex-specific differences in cadmium levels at older ages are not due to iron-cadmium interactions, and that further studies are required to identify the source of these differences. In summary, the potential causes of sex-specific differences in the blood levels of manganese, lead, and cadmium differ from each other, although all these three metals are associated with iron deficiency. Therefore, other factors such as estrogen effects, or absorption rate as well as iron deficiency, should be considered when addressing environmental exposure to toxic metals and sex-specific differences in the blood levels of these metals.

Manganese (Mn) is an essential trace element for humans and animals, but excess intake of Mn can lead to adverse developmental outcome. Few studies have investigated the effects of deficiency or excess of Mn on the human foetus. In this study, we assessed the quantitative relationship between maternal blood Mn and birth weight of a newborn.

Lee H, et al. J Korean Med Sci. 2016 Apr;31(4):579-584. https://doi.org/10.3346/jkms.2016.31.4.579