Body burden and influencing factors of polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) in male workers from a municipal waste incineration plant in China

Emissions of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) from municipal solid waste incinerators (MSWIs) have aroused public concern around the world. However, biomonitoring evidence regarding the influence of MSWIs on the human body burden of PCDD/Fs is scarce. The aim of this study is to investigate the human body burden levels of PCDD/Fs in MSWI workers and to further explore the potential influencing factors, including duration of occupation and dietary habits, on the PCDD/F levels. A total of 98 paired serum samples from MSWI workers and non-MSWI workers were collected. Seventeen 2,3,7,8-chlorine substituted PCDD/Fs in the serums were analyzed using an isotope dilution high-resolution gas chromatograph/high-resolution mass spectrometer (HRGC/HRMS). The results showed that the mean levels of toxic equivalent (TEQ)-PCDD/Fs for the MSWI workers and the control group were 18.28 pg TEQ g^-1 lipid and 5.81 pg TEQ g^-1 lipid, respectively. Significantly higher concentrations of PCDD/Fs existed in the incinerator workers compared with the control subjects after adjustment of the confounding factors. OCDD was the most abundant congener in both the MSWI workers and the control subjects, accounting for 82.2% and 89.4% of the ∑₁₇PCDD/Fs, respectively. The serum levels of PCDFs in the MSWI workers increased with the duration of occupation (β = 0.498, P = 0.031), and a higher total concentration of PCDD/Fs were present in senior workers classified as production supervisors than routine operation staff (β = 8.809, P = 0.008). No significant relationship was found between the PCDD/F concentrations and dietary habits. This study was the first to explore the associations between the body burden of PCDD/Fs and occupational exposure as well as dietary intake of MSWI workers in China. The findings provide scientific information for health risk assessments of human exposure to PCDD/Fs.

Human biomonitoring of metals in workers at the waste-to-energy incinerator of Turin: An Italian longitudinal study

Evidence of negative health effects of solid waste management is uncertain. Available reviews suggests the use of biomarkers in human biomonitoring (HBM) to detect low exposure levels. In September 2013, a waste-to-energy plant located in the Turin (Italy) went into operation. The SPoTT (acronym for Population health Surveillance in the Turin incinerator's area) monitoring program was set up to assess the potential health impact caused by the plant. The paper illustrates the results of HBM of metals in the workers before the plant went into operation and then at 1 year and 3 years. This study is one of the few focusing on workers with a longitudinal design (the first in Italy). Eighteen metals in urine and lead in blood were determined by sector field inductively coupled plasma mass spectrometry. Information on participant habits and other characteristics that could potentially affect metals concentrations were collected via a structured questionnaire. Subjects were classified according to their work role at the facility: administrative staff workers (AW); plant workers (PW). Nonparametric methods were used to evaluate the changes in metals concentration over time. Comparison of the metals concentration in the samples taken at baseline and at the following two-time points shows a general decrease in levels: urinary concentration of beryllium (Be), cobalt (Co), mercury (Hg), Ir, nickel (Ni), tin (Sn), thallium (Tl), and blood level of lead (Pb) among the PW and Ir and Pd among the AW were significantly lower at T2 versus baseline. A decrease was also recorded in arsenic (As) among the PW and in cadmium (Cd), chromium (Cr), palladium (Pd), rhodium (Rh), and zinc (Zn) for both groups, whereas the levels of copper (Cu) and vanadium (V) remained unchanged over time. The downward trend remained also after taking confounding factors into account. The only exceptions were Mn, Pt, Sb among the PW: increase levels between T0 and T2 were recorded, which cannot be specifically attributable to the plant activity. The median urinary and blood concentrations of the metals were lower than those reported in the literature and were below the occupational reference values at all three-time points. Our results are consistent with those reported for the cohort of local residents and with the ambient air measurements.

Biomonitoring of toxic metals in incinerator workers: A systematic review

Exposure to chemicals released during urban waste disposal and treatment is increasingly regarded as a potential occupational health issue. Indeed, several toxic metals emitted by an incinerator, including As, Be, Cd, Cr, Pb, Mn, Hg, Ni and V, have potentially toxic properties and their exposure, therefore, may be of concern for the health of the workers involved. The levels of exposure should therefore be carefully measured. Environmental monitoring, however, may be unable, alone, to assess true exposure, due to its intrinsic limitations mainly concerning its inability to assess oral and dermal absorption. In these cases biological monitoring may represent a fundamental supplementary tool for the definition of the workers' true occupational exposure and for the prevention of the related health effects. There is, therefore, an increasing interest in developing and using, in these workers, sensitive and specific biomarkers for health risk assessment, particularly at low or even very low levels of exposure. Despite the large number of original and review articles present in the literature on the biomonitoring of workers exposed to metals, the data on subjects employed in waste treatment activities are scattered and results are sometimes inconsistent. This is the first systematic review, performed according to PRISMA methodology, of the major studies investigating the levels of different toxic metals measured in the main biological matrices (blood, urine, hair) of incinerator workers. The results show that the levels of metals measured in incinerators' workers are generally low, with some notable exceptions for Cd and Pb. These results, though, can be affected by several confounders related either to non-occupational exposure, including diet, area of residence and others, and/or by a number of methodological limitations, as we found in the reported studies. Future work should focus on an integrated approach, using ideally both biological and environmental monitoring. A particular emphasis should be given to the measurement of the different granulometric fractions of the dust containing metals, i.e. inhalable, thoracic, respirable and ultrafine fractions. Moreover, an accurate description of the work tasks and the characteristics and levels of non-occupational exposure should always be provided.