**6. Work-related stress**

*Safety and Health for Workers - Research and Practical Perspective*

agents [62, 67, 68].

occupational hazards.

contributes to an unequal distribution of working conditions as well as exposure to different physical and psychological risks between sexes [64]. Women are also more likely to have part-time or temporary contracts than men [65]. Job segregation strongly contributes to different hazard exposure and consequently to different health outcomes. Examples of these could include skin diseases that women suffer when working with wet hands, chemical cleaning, and sterilizing agents as well as protective gloves containing latex dust. Several studies have also reported male-female differences in the prevalence of symptoms of work-related musculoskeletal disorders, some arising from workplace exposure differences [66]. In this regard, it is important to emphasize that gender-related biological differences may result in differential vulnerability of women and men at the same physical, chemical, and biological workplace factors such as hazardous substances and biological

Many studies, on which occupational safety and health are based on, have been performed on men excluding women [60]. In addition, gender differences have been rarely studied in epidemiologic research related to occupational safety and health. For many years, Food and Drug Administration guidelines specifically precluded participation of women in many toxicological studies [69]. Currently, it is believed that women and men differ in many aspects of biological vulnerability to

Chemicals may induce variable toxic actions according to the amount absorbed by the body (or Body Burden) [70]. Toxicological studies have defined the threshold limit value (TLV) or daily level to which a worker can be exposed without adverse health effects. However, TLV has been calculated on men, and few studies have measured exposure for men and women in the same occupational setting. Toxicity varies depending how quickly and efficiently toxic agent is metabolized. Generally, the relationship between exposure dose, absorbed dose, and effective dose is complex and depending on various factors that are studied by pharmacokinetics or toxicokinetic that is split up in four different phases [(1) absorption across the body barriers (e.g., skin and hair), (2) the distribution into the body, (3) the metabolism, and (4) the excretion] are all subject to sex differences [71]. Absorption probably differs between women and men due to the condition of the skin (with or without cosmetics), number of hair follicles, breathing rates, and respiratory volume. It has been identified a number of chemical agents for which the body burden is different in women and men even when they carry out the same job [70]. Differences in "Body Burden" are clarified by the anthropometric differences between sexes according to muscle mass, fatty tissue, and bone mass. Women have a higher percentage of body fat than men. Adipose tissue makes women more susceptible to dangerous fat-soluble substances, such as organic solvents (e.g., benzene and trichloroethylene). All together these factors affect the extent of distribution of the chemical into the body compartments. However, the greater role in toxicokinetic variability is played by differences in xenobiotic metabolism [71]. Primarily, these reflect the differences in gene expression for enzymes of the CYP450 superfamily, the major family of enzymes involved in the metabolism of chemical agents. Sexbased variance in the expression and activity of CYP isoenzymes are been reported in different studies [71]. In addition, CYP450 activity is also modulated by sex hormones [72, 73]. Finally, renal excretion of compounds is higher in men than in women [71]. It is clear that the limits defined by TLV should be monitored according to gender differences, in order to determine appropriate procedures in OSH. Work-related asthma is one of the most frequently reported occupational lung diseases, and sensitivity to asthmatic attacks is an emblematic example of gender differences in workplaces as the asthmatic attacks are closely related to hormonal changes [72, 73]. Men are highly sensitive in prepubescent age, but

**62**

Work-related stress can be defined as the adverse reaction people have to excessive pressures or extra demand placed on them at workplace [74]. Generally, work-related stress is due to the type of work, position in the social hierarchy, horizontal and vertical discrimination, sexual harassment, and the situation outside of work. In this scenario, work-related stress is an important intermediate factor linking workers in more disadvantaged socioeconomic positions with poor health [74, 75]. Factors like skills and experience, age, gender, ethnicity or disability may all affect whether an employee can cope. Employees feel stress when they cannot cope with pressures and other issues [74, 75]. Both women and men report high levels of work-related stress but stress affects people differently and what stresses one person may not affect another depending on the context in which people live and work [74, 75]. Stress is not an illness but it can make workers ill. As described above, stress raises blood pressure, increases the risk of heart disease [76], and weakens the immune system. It can cause depression and even lead to suicide and cause a number of mental and physical disorders [77, 78]. Finally, stress can increase drinking or smoking, reinforcing inequalities [28, 29].
