Cyclopentanone: an unexpected airborne pollutant in a plastics moulding plant.

  • Paolo Sacco Istituti Clinici Scientifici Maugeri – Centro Ricerche Ambientali – Vigonza
  • Roberto Calisti ASUR MARCHE- SPreSAL Epi Occ-Civitanova Marche
  • Rossano Mei ASUR MARCHE- SPreSAL Epi Occ-Civitanova Marche
  • Caterina Boaretto Istituti Clinici Scientifici Maugeri – Centro Ricerche Ambientali – Vigonza
  • Franco Quaglio Istituti Clinici Scientifici Maugeri – Centro Ricerche Ambientali – Vigonza
  • Laura Zaratin Istituti Clinici Scientifici Maugeri – Centro Ricerche Ambientali – Vigonza
Keywords: occupational exposure ; cyclopentanone ; tetrahydrofuran ; plastics moulding; thermal degradation; risk assessment, risk control strategies

Abstract

A Local Unit of the Italian Public Health Service for Occupational Safety and Health was consulted by a male worker complaining an acute respiratory distress, sharply arisen during his previous nocturnal work shift in a plastics moulding plant.

Some months before, a female worker from the same plant had been sent to consultation at the above mentioned Local Unit, for suffering hacking cough, thoracic heaviness and mild dyspnoea every time she entered the workshop at the beginning of the workweek.

The plant produces soles and components for footwear by injection moulding of a variety of thermoplastic compounds (mainly thermoplastic rubber and thermoplastic polyurethane); many batches of these compounds are charged with a wide range of pigments.

For the above, the Public Health Service Local Unit activated an inspection inside the plant, evaluating the results of samplings of airborne total dusts and airborne chemicals performed by the firm consultants: subsequently, both the firm consultants and the Public Health Service carried out a specific monitoring of airborne chemicals applying the respective standard techniques.

The early results from both the sources showed no significant presence of aldehydes and other VOCs (Volatile Organic Compounds), with the sole relevant exceptions of an, at the moment, undetermined chemical revealed, in all the first five samplings for aldehydes collected by the Public Health Service, with responses ranging from 1484 to 1598 µg / m3, and of a minor concentration of tetrahydrofuran in two samples for VOCs (standard set) collected by the Public Health Service.

A subsequent series of three quali-quantitative samplings performed by the Public Health Service at three different plastic presses by means of a different sampling technique (adsorption onto Tenax tubes) revealed an unexpected, outstanding presence of cyclopentanone, corresponding to the above mentioned, initially unidentified chemical.

After a set of interventions determining a substantial amelioration of the general forced ventilation inside the workshop, further samplings were performed by both the firm consultants and the Local Unit of the Public Health Service, searching for both aldehydes and other VOCs (standard set) and revealing no persisting considerable presence of cyclopentanone and other airborne relevant pollutants, except for some tetrahydrofuran in the Public Health Service samples. No other cases of respiratory disease subsequently emerged.

Cyclopentanone is a fragrant chemical whose toxic potential has been poorly studied. It is reasonable that cyclopentanone vapours, such as vapours of other chemicals from the thermal degradation products of thermoplastic blends, develop inside the plastic moulding workshop in particular conditions when some compounds are overheated; this situation could be accompanied by dusts’ emission too. The two reported cases, classifiable as “sentinel events” though clinically not weighty, reasonably were a consequence of an occurrence of such situations.

In any case, the reported results suggest that standard samplings of VOCs not always can reveal all the relevant species in a plastic moulding workshop and that, especially in the presence of “sentinel events” such as cases of respiratory distress, this kind of work environments needs both close examinations and competent risk assessments, and specific preventive interventions.

 

References

Cocheo, V., Boaretto, C., Sacco, P., 1996. High uptake rate radial diffusive sampler suitable for both solvent and thermal desorption. Am. Ind. Hyg. Assoc. J., 57, 897-904.

de Oliveira Gomes. A.C., Gomes Oliveira, M., Paranhos, M., Guenther Soares. B., 2013. Thermal protection of polyamide 6 / acrylonitrile – butadiene rubber thermoplastic - vulcanizates: influence of type and content on blend properties. Rubber Chem Technol; 86(2): 286-298.

Elovaara, E., Pfäffli, P., Savolainen, H., 1984. Biochemical effects and decreased body burden of cyclopentanone by extended vapour inhalation. Acta Pharmacol Toxicol (Copenh); 55(4): 283-6.

New Jersey Department of Health and Senior Services, 2000. Hazardous substance fact sheet. Cyclopentanone. nj.gov/health/eoh/rtkweb/documents/fs/0585.pdf. Last on line access 2019 Aug 21.

International Agency for Research on Cancer (IARC), 2019. Some chemicals that cause tumors of the urinary tract in rodents. IARC Monographs, volume 119: 205-224.

National Toxicology Program (NTP), 1998. NTP toxicology and carcinogenesis studies of tetrahydrofuran (CAS No. 109-99-9) in F344/N rats and B6C3F1 mice (inhalation studies). Natl Toxicol Program Tech Rep Ser; 475: 1-244.

RIFM Expert Panel, Belsito, D., Bickers, D., Bruze, M., Calow, P., Dagli, M.L., Dekant, W., Fryer, A.D., Greim, H., Miyachi Y., Saurat, J.H., Sipes, I.G., 2012. A toxicologic and dermatologic assessment of cyclopentanones and cyclopentenones when used as fragrance ingredients. Food Chem Toxicol; 50 Suppl 3: S17-56.

Scognamiglio, J., Jones, L. Letizia, C.S., Api, A.M., 2012. Fragrance material review of cyclopentanone. Food Chem Toxicol; 50 Suppl 3: S608-12.

Smith, J.N., White, G.V. II, White, M. I, Bernstein, R., Hochrein, J.M., 2012. Characterization of volatile Nylon 6.6 thermal-oxidative degradation products by selective isotopic labelling and cryo-GC/MS. J Am Soc Mass Spectrom; 23: 1579-1592.

Soto-Valdez H., Gramshaw, J.V.V., Vandenburg, H.J., 1997. Determination of potential migrants present in Nylon “microwave and roasting bags” and migration into olive oil. Food Addit Contam; 14(3): 309-18.

PubChem. U.S. National Library of Medicine, National Center for Biotechnology Information, 2019. Compound summary. Cyclopentanone / C5H8O. https://pubchem.ncbi.nlm.nih.gov. Last on line access 2019 Aug 21.

Published
2019-12-22