## 1 Biomarkers and Human Biomonitoring in Occupational Medicine
Statistically significant differences (\(p\) = 0.03) were found between the free 2,5-HD urinary levels according to the vehicular traffic intensity within the area of residence and to body mass index of subjects. The background levels of free 2,5-HD found in this study could contribute to the definition of reference values of the general population non-occupationally exposed and could be useful to toxicologists and industrial hygiists to determine whether workers have been exposed to higher levels of n-hexane than the general population. The influence of genetic polymorphisms of the enzymes for DNA repair and detoxification of reactive intermediates on spontaneous and bleomycin-induced (BLM) genotoxic damage in workers exposed to very low doses of ionizing radiation (IR) (mean cumulative dose 5.31 mSv) was studied by [PERSON] et al. [10]. In all the subjects examined, the frequency of chromosome aberrations (CAs) and micronucleeli (MN), both spontaneous and BLM-induced, the Comet assay parameters (tail intensity), the genotypic variants of the DNA repair enzymes XRCC1 (Arg194 Trp, Arg280 His, Arg399 Gln), XRCC3 (Thr241 Met), XPD (Lys751 Gln), and of the detoxification enzymes GSTM1 and GSTT1 (null genotype) and BLMH (A1450G) were determined. Among the biomarkers considered, only the frequency of total CAs (\(p<0.05\)), and in particular of chromosome breaks (\(p<0.01\)), was found to be significantly higher in the exposed workers than the controls. The frequency of spontaneous MN was higher in subjects with at least one allelic variant in XRCC1 than in carriers of the wild type, but again only in exposed workers (\(p=0.046\)). Linear regression analysis showed a positive dependency of the frequency of spontaneous chromosome breaks on occupational exposure, and a dependency of the frequency of BLM-induced MN negative on occupational exposure and positive on alcohol consumption and the null GSTM1 genotype. This study points out that the frequency of chromosome breaks seems to be a useful cytogenetic biomarker for exposure to very low doses of IR, while only the combined effect of different gene variants or genetic, occupational, and lifestyle habits factors seems to be able to modulate the genotoxic effect of very low doses of IR [10]. Endocrine disruptors are an emerging chemical risk in the workplace. [PERSON] et al. [11] examined the occupational exposure to phthalates of hairdressing apprentices from Slovakia and the outcomes related to body composition and pulmonary functions. They observed a decrease of % of predicted values of forced vital capacity (FVC% of PV) related exposure to mono(2-ethyl-5-oxohexyl) phthalate (MEOHP; \(p=0.054\)) and sum of bis(2-ethylhexyl) phthalate metabolites (\(\sum\)DEHP; \(p=0.037\)), and a decrease of % of predicted values of vital capacity (VC% of PV) related to exposure to MEOHP, \(\sum\)DEHP (\(p=0.008\)), and mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP; \(p=0.014\)) in females. They detected associations between forced vital capacity (FVC) with weight (\(p=0.002\)) and fat-free mass index (FFMI, \(p=0.010\)). Vital capacity (VC) and VC% of PV increased with weight, body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-hip ratio (WHR), the waist-heightratio (WHtR), fat mass index (FMI), and FFMI in females (\(p\leq 0.014\)). Results of multivariate regression between PFT and anthropometric parameters adjusted to phthalates indicated exposure to MnBP and MEHP, changing body structure (BMI and FMI), subsequently affecting values of FEV\({}_{1}\)/FVC. These data indicate that hairdressing-related phthalate exposure is significant. Moreover, biomonitoring of phthalates in this type of occupational environment is needed to regulate the harmful effect on health. Adequate attention should be given to education about potential hazards and preventive strategies in this occupational environment. An appropriate preventive strategy by pulmonary function test in periodical monitoring can detect early signs of pulmonary dysfunctions [11].