Fullerenes: Characteristics of the substance, biological effects and occupational exposure levels

AbstractAir force ground crew personnel are potentially exposed to fuels and lubricants, as raw materials, vapours and combustion exhaust emissions, during operation and maintenance of aircrafts. This study investigated exposure levels and biomarkers of effects for employees at a Danish air force military base. We enrolled self-reported healthy and non-smoking employees (n = 79) and grouped them by exposure based on job function, considered to be potentially exposed (aircraft engineers, crew chiefs, fuel operators and munition specialists) or as reference group with minimal occupational exposure (avionics and office workers). We measured exposure levels to polycyclic aromatic hydrocarbons (PAHs) and organophosphate esters (OPEs) by silicone bands and skin wipes (PAHs only) as well as urinary excretion of PAH metabolites (OH-PAHs). Additionally, we assessed exposure levels of ultrafine particles (UFPs) in the breathing zone for specific job functions. As biomarkers of effect, we assessed lung function, plasma levels of acute phase inflammatory markers, and genetic damage levels in peripheral blood cells. Exposure levels of total PAHs, OPEs and OH-PAHs did not differ between exposure groups or job functions, with low correlations between PAHs in different matrices. Among the measured job functions, the UFP levels were higher for the crew chiefs. The exposure level of the PAH fluorene was significantly higher for the exposed group than the reference group (15.9 ± 23.7 ng/g per 24 h vs 5.28 ± 7.87 ng/g per 24 h, p = 0.007), as was the OPE triphenyl phosphate (305 ± 606 vs 19.7 ± 33.8 ng/g per 24 h, p = 0.011). The OPE tris(1,3-dichlor-2-propyl)phosphate had a higher mean in the exposed group (60.7 ± 135 ng/g per 24 h) compared to the reference group (8.89 ± 15.7 ng/g per 24 h) but did not reach significance. No evidence of effects for biomarkers of systemic inflammation, genetic damage or lung function was found. Overall, our biomonitoring study show limited evidence of occupational exposure of air force ground crew personnel to UFPs, PAHs and OPEs. Furthermore, the OH-PAHs and the assessed biomarkers of early biological effects did not differ between exposed and reference groups.

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DNA effects of low level occupational exposure to extremely low frequency electromagnetic fields (50/60 Hz)

Toxicology and Industrial Health ◽

10.1177/0748233719851697 ◽

2019 ◽

Vol 35 (6) ◽

pp. 424-430 ◽

Cited By ~ 2

Author(s):

Rezvan Zendehdel ◽

Il Je Yu ◽

Behnam Hajipour-Verdom ◽

Zahra Panjali

Keyword(s):

Dna Damage ◽

Occupational Exposure ◽

Low Frequency ◽

International Agency ◽

Tail Moment ◽

Limit Values ◽

Strand Breaks ◽

Extremely Low Frequency ◽

Exposed Population ◽

Exposure Levels

Aims: Exposure to extremely low frequency magnetic fields (ELF-MF) occurs from natural and artificial sources. Although ELF-MF has been classified as a suspected humans carcinogen agent by the International Agency for Research on Cancer, little is known of the effects of ELF-MF at lower exposure levels of the recommended range. In the present study, DNA damage in the peripheral blood cells of power line workers was investigated. Materials and Methods: Occupational exposure to ELF-MF in a power plant was measured using the National Institute for Occupational Safety and Health (NIOSH) manual. Single-strand breaks (SSBs) in DNA were evaluated in 29 male utility workers as the exposed population and 28 male support personnel as the control subjects using the comet assay. Effects of ELF-MF on subjects were evaluated using DNA percent in tails, tail length, olive length, and tail moment. Results: Occupational exposure levels to ELF-MF in the utility workers were less than the threshold limit values (TLV) recommended by the American Conference of Government Industrial Hygienist (ACGIH). The median value of the magnetic field at the working sites was 0.85 µT. Induction of DNA damage was observed for the exposed workers compared with the controls. Olive length, tail moment, and tail DNA percent increased significantly ( p < 0.05) in the utility workers. Conclusions: Exposure to ELF-MF at levels less than the ACGIH exposure limit can produce DNA strand breaks.

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Exposure and Risk Assessment with Respect to Contaminated Soil: Significance of Biomarkers and Bioavailability

International Journal of Toxicology ◽

10.1080/109158197227044 ◽

1997 ◽

Vol 16 (4-5) ◽

pp. 419-432 ◽

Cited By ~ 6

Author(s):

Urvashi Rangan ◽

Christine Hedli ◽

Michael Gallo ◽

Paul Lioy ◽

Robert Snyder

Keyword(s):

Health Risk ◽

Exposure Assessment ◽

Health Risks ◽

Contaminated Soil ◽

Biological Effects ◽

Chemical Exposure ◽

Subsequent Exposure ◽

Gastrointestinal Barrier ◽

Exposure Levels

The evaluation of health risk from chemical exposure is evolving in concept and practice. The ability to sensitively detect levels of chemicals in the environment has served as the traditional foundation for determining exposure levels and consequent health risks. More recently, however, other parameters have been constructed to probe the pathway between environmental levels of a chemical and the biological effects of subsequent exposure. Among these, two that are discussed in this paper are bioavailability and biomarker determinations. Chemicals in the environment often are associated with a medium such as airborne particulate, water, or soil. The interaction between the chemical and its medium is dependent on the physicochemical properties of the system. In some cases, such as 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) in soil, the chemical becomes partially and irreversibly bound to the medium. Animalingestion studies of TCDD-contaminated soil suggest that some of the TCDD remains bound to the soil and does not cross the gastrointestinal barrier during digestion, and therefore only a fraction of the TCDD enters the blood and becomes bioavailable. The characterization of bioavailability provides for more accurate exposure assessment. Biomarker information potentially can validate exposure assessment information from bioavailability studies, elucidate specific biological effects from chemical exposure, and investigate genetic susceptibility issues that may increase the likelihood that an individual or population will experience increased health risks. Benzene-induced chromosome damage is discussed as an example of a significant biomarker that has demonstrated the potential for providing information useful for accurately prediction health risk.

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