Investigations on cytotoxic and genotoxic effects of laser printer emissions in human epithelial A549 lung cells using an air/liquid exposure system

Abstract

Exposure to emissions from laser printers during the printing process is commonplace worldwide, both in the home and workplace environment. In the present study, cytotoxic and genotoxic effects of the emission from five low to medium-throughput laser printers were investigated with respect to the release of ozone (O(3) ), volatile organic compounds (VOC), particulate matter (PM), and submicrometer particles (SMP) during standby and operation. Experiments were conducted in a 1 m(3) emission chamber connected to a Vitrocell® exposure system. Cytotoxicity was determined by the WST-1 assay and genotoxicity by the micronucleus test in human A549 lung cells. The five laser printers emitted varying but generally small amounts of O(3) , VOC, and PM. VOC emissions included 13 compounds with total VOC concentrations ranging from 95 to 280 μg/m(3) (e.g., 2-butanone, hexanal, m,p-xylene, and o-xylene). Mean PM concentrations were below 2.4 μg/m(3). SMP number concentration levels during standby ranged from 9 to 26 particles/cm(3). However, three of the printers generated a 90 to 16 × 10(3) -fold increase of SMP during the printing process (maximum 294,460 particles/cm(3)). Whereas none of the printer emissions were found to cause cytotoxicity, emissions from two printers induced formation of micronuclei (P < 0.001), thus providing evidence for genotoxicity. As yet, differences in biological activity cannot be explained on the basis of the specific emission characteristics of the different printers. Because laser printing technology is widely used, studies with additional cytogenetic endpoints are necessary to confirm the DNA-damaging potency and to identify emission components responsible for genotoxicity.

Toxicological effects of PM0.25–2.0particles collected from a photocopy center in three human cell lines

“…In vitro (fine particle dosing) In vitro (nanoparticle dosing) (Khatri et al, 2013b) In vivo (Khatri et al, 2013a) " " " " " " IL-8 *** ** ** *** *** *** *** IL-6 ** --*** --*** IL-1b Bello et al, 2013) and cyto-/toxicity potential (Tang et al, 2012). No data exist at present regarding variations in the chemical composition and toxicity of similar size-fractionated particles from other copy environments.…”

“…Such devices are known to emit potentially harmful pollutants, more notably nanoparticles, raising concern over toxicological effects resulting from chronic exposures to such pollutants (Bar-Sela & Shoenfeld, 2008;Bello et al, 2013;Khatri et al, 2013a;Lee & Hsu, 2007;Manikantan et al, 2010;Pirela et al, 2013;Tang et al, 2012;Theegarten et al, 2010). In the past, the focus of emission studies has been on respirable particulate matter, ozone, volatile organic compounds (VOC) and semi-volatile organic compounds (SVOC) (Destaillats et al, 2008;Tuoni et al, 2000).…”

“…A major source of PM 0.25-2.0 in the copy center environment could be aggregation of nanoparticles over time. Additionally, some toner fragments are emitted as fine particles themselves (Bello et al, 2013;Lee & Hsu, 2007;Tang et al, 2012). As primary particle/aggregate size and chemistry of the PM 0.25-2.0 fraction differs from that of the nanoscale fraction, it is expected their deposition sites, cellular uptake rates, clearance, translocation and induced cytotoxic effects may also differ significantly, as is common for different fractions of air pollution or other contaminants (e.g.…”

Genotoxic properties of XLR-11, a widely consumed synthetic cannabinoid, and of the benzoyl indole RCS-4

“…It mimics the physiological conditions in the respiratory tract and eliminates the interactions of potential constituents with culture media (Thorne and Adamson 2013). These experiments were conducted with the buccal cells (TR-146) and with the human cell line A-459 which is derived from lung fibroblasts (Lieber et al 1976) and was used in earlier gaseous exposure experiments (Majeed et al 2014; Tang et al 2012). …”

Personal and Atmospheric Concentrations of Ozone in Southeastern Hyogo Prefecture, Japan

“…We cannot explain these results, perhaps because our questionnaire did not include questions about the office or house construction, equipment, and outdoor environment that they spent during sampling period. Items such as a window fan, 9) a laser printer, 19) or an air cleaner 20) might increase ozone levels, and the close proximity of a main road might be decrease the ozone level. 9) An improved questionnaire will be used in our next study.…”