Urinary levels of metal elements in the non-smoking general population in Italy: SIVR study 2012-2015

The purpose of this study of the Italian Society of Reference Values (SIVR) was to provide the reference values for metals in the urine of the Italian general population. Thirteen sampling centres situated in the north, centre and south of Italy took part in this project. Each sampling centre selected 20 adult subjects. The sample was made up of 120 male and 140 female non-smokers or smokers who had abandoned the habit at least 5 years previously, aged between 18 and 60 years. Urine samples were obtained from the same subjects in June and again in November of the same year. During collection of these two samples, we administered an ad hoc questionnaire designed to assess factors that might influence exposure and the results of the study such as personal characteristics, occupational or extra-occupational activities, dietary habits, the presence of dental fillings containing amalgam, the frequency and mode of exposure to passive smoking and exhaust gases of motor vehicles (traffic). Therefore, the urinary levels of thirteen trace elements (Be, Cd, Co, Cr, Cu, In, Mn, Ni, Pb, Pt, Sb, Tl and V) were determined by Inductively Coupled Plasma Mass Spectrometry. The concentrations obtained (95th percentile) are in μg/L: 0.034, 0.900, 2.24, 0.600, 24.0, 0.013, 1.53, 4.44, 2.64, 0.022, 0.095, 0.759 and 0.855 for Be, Cd, Co, Cr, Cu, In, Mn, Ni, Pb, Pt, Sb, Tl and V, respectively. Further studies with a larger number of subjects are needed in order to continue the biomonitoring of the Italian general population and to monitor the modified levels over time

Methodology to define biological reference values in the environmental and occupational fields: the contribution of the Italian Society for Reference Values (SIVR)

BACKGROUND: Biological reference values (RVs) explore the relationships between humans and their environment and habits. RVs are fundamental in the environmental field for assessing illnesses possibly associated with environmental pollution, and also in the occupational field, especially in the absence of established biological or environmental limits. OBJECTIVES: The Italian Society for Reference Values (SIVR) determined to test criteria and procedures for the definition of RVs to be used in the environmental and occupational fields. METHODS: The paper describes the SIVR methodology for defining RVs of xenobiotics and their metabolites. Aspects regarding the choice of population sample, the quality of analytical data, statistical analysis and control of variability factors are considered. The simultaneous interlaboratory circuits involved can be expected to increasingly improve the quality of the analytical data. RESULTS: Examples of RVs produced by SIVR are presented. In particular, levels of chromium, mercury, ethylenethiourea, 3,5,6-trichloro-2-pyridinol, 2,5-hexanedione, 1-hydroxypyrene and t,t-muconic acid measured in urine and expressed in micrograms/g creatinine (μg/g creat) or micrograms/L (μg/L) are reported. CONCLUSIONS: With the proposed procedure, SIVR intends to make its activities known to the scientific community in order to increase the number of laboratories involved in the definition of RVs for the Italian population. More research is needed to obtain further RVs in different biological matrices, such as hair, nails and exhaled breath. It is also necessary to update and improve the present reference values and broaden the portfolio of chemicals for which RVs are available. In the near future, SIVR intends to expand its scientific activity by using a multivariate approach for xenobiotics that may have a common origin, and to define RVs separately for children who may be exposed more than adults and be more vulnerable

Biological monitoring of exposure to low concentrations of benzene in workers at a metallurgical coke production plant: new insights into S-phenylmercapturic acid and urinary benzene

Context: Urinary S-phenylmercapturic acid (SPMA) and benzene (U-Ben) are usually measured at the end of the work shift (ES), although their kinetic of elimination is not clearly known. Objective: To investigate SPMA and U-Ben elimination 16 h after the ES, in 93 coke production workers exposed to low benzene concentrations. Materials and methods: Airborne benzene (A-Ben) was measured by passive samplings, while SPMA, U-Ben, methyl-tert-butyl ether (U-MTBE), cotinine (U-Cot) and creatinine were determined on urine samples collected at ES and before the beginning of the next work shift (next BS). Results: Median A-Ben concentrations were 17.2 mg/m3 in the personal and 34.7 mg/m3 in the stationary samplings. SPMA was always detectable, whereas U-Ben was below the limit of quantification in 26.7% of the ES and 35.6% of the next BS samples, and U-MTBE in more than the 80.0% of the samples. At both the sampling times, SPMA and U-Ben showed a positive dependence on personal A-Ben, as well as on creatinine and U-Cot values. Discussion and conclusion: SPMA and U-Ben at the next BS were dependent on the exposure to low benzene concentrations suffered in the previous work shift, prompting a reconsideration of the urine sampling time recommended by the American Conference Governmental Industrial Hygienists (ACGIH)