Formaldehyde exposure patterns in a set of Italian indoor workplaces with and without specific emission sources - 2011-2018

Roberto Calisti, Lucia Isolani, Rossano Mei


Formaldehyde is a ubiquitous carcinogen causing widespread exposures, both occupational and non- occupational.

In order to prevent both short-term and long-term adverse health effects (cancer included), different guideline values and limit values for indoor formaldehyde vapours concentration have been proposed.

There is a widespread debate about the existence of a threshold exposure value for the arising of carcinogenic effects of formaldehyde, impacting on the significance of the proposed limit values(health-based vs. risk-based).

Specific criticalities arise when specific emission sources are present inside a workplace and it is necessary to distinguish background from more significant exposure levels, establishing strategies for a proper management of the so-called “low” occupational exposures.

The aim of this paper sets not about the discussion about safe vs. not-safe exposure levels, but about the necessity to distinguish scenarios of background vs. significant (“qualified”) occupational indoor exposures to formaldehyde. Specific preventive and protective actions are requested in the latter case.

The paper presents the patterns of formaldehyde vapours’ concentration measured in a set of indoor Italian workplaces with and without specific emission sources, discusses a pragmatic cut-off value of 35 μg m-3 for long exposures in order to identify significant (“qualified”) occupational exposures and proposes clues about the efficacy of distinct exposure management approaches.

Over the 2011 – 2018 period, a sequence of 117 passive diffusive indoor samplings was performed: 26 samplings (all environmental) lasting 1 hour or longer in workplaces without specific sources of formaldehyde, 75 samplings (69 environmental, 6 personal) lasting 1 hour or longer in workplaces with specific sources of the agent, and 16 samplings (5 environmental, 11 personal) lasting less than 1 hour in workplaces with specific sources of the agent.

In the data analysis, the samplings were grouped according to duration, i.e. more than 1 hour (“long samplings”) and less than 1 hour (“short samplings”).

The mean formaldehyde levels determined from environmental long samplings in workplaces with and without specific emission sources (plastics moulding factories, foundries, abrasive disksmanufacturingplants, a women’s hairdressing salon, a surgical block where formalin was used for tissue fixation, a hospital Histopathology unit vs. an office, a medical practice, a waiting room, a reception hall, a sterilization room were no formaldehyde-based product was in use, and a conference hall) were 16.6μg m-3 and 12.2 μg m-3 respectively. Both groups of values are, as a whole, low and very close between them, clearly as a result of more or less effective industrial hygiene measures (enclosure of emission points, local exhausts aspiration, general ventilation) where specific sources are present.

However, personal long samplings in a subset of the aforesaid workplaces with occupational exposure to formaldehyde showed a mean value of exposure of 34.8 μg m-3.

In general, personal samplings, both longer and shorter than one hour, showed formaldehyde levels higher than the corresponding environmental ones: twice higher in the above mentioned women’s hairdressing salon (43.1 μg m-3 vs 21.9 μg m-3), more than four times higher in three farms and a mortuary (the mean values from short and long samplings were found to be 512.3μg m-3 and 122.2 μg m-3 respectively).

These results highlight the need to pay attention to all aspects of the workers’ activities involving any condition of close proximity to the emission sources which increase individual exposure.

A growing pattern of mean formaldehyde levels emerged, from 12.2μg m-3 (long samplings, no specific sources) up to 512.3μg m-3 (short samplings, presence of specific sources).

In the workplaces with no specific formaldehyde sources (all environmental long samplings), the level of 30 μg m-3 was never exceeded, with the only exception (31 μg m-3) of an office where the sampler had been located very close to a sporadically used laser printer.

Only a subset of long samplings taken in workplaces with specific formaldehyde sources showed levels exceeding 30 μg m-3, up to 75 μg m-3: these were strictly related to the inadequacy of emission point enclosures, to faulty local exhaust aspiration and to poor general ventilation.

Top values largely exceeding 100 μg m-3 were observed in short samplings from the three above mentioned farms (where the problem was quickly worked out each time by replacing all formaldehyde-based products) and from the mortuary (a setting where the use of formaldehyde-free products for corpse preservation is not an established routine yet).

Theseresults support the feasibility of adopting conventional, pragmatic cut-off values for indoor formaldehyde levels, in order to conventionally distinguish between background and significant (“qualified”) occupational exposures in presence of specific emission sources of the agent.



formaldehyde; occupational exposure; passive sampling, risk assessment, risk control strategies

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ACGIH, 2017. 2017 TLVs and BEIs. Cincinnati, OH.

Aprea, C., Bozzi, N., Nanni C., Cardelli, D., Pulcinelli, R., Sciarra, G., 2007. Formaldeide e acetaldeide nelle rivendite di mobili. Giornale degli Igienisti Industriali, 32 (2): 109-119.

Baker, D.C., 1994. Projected emissions of hazardous air pollutants from a Shell coal gasification process-combined-cycle power plant. Fuel, 73 (7): 1082–1086.

Belanger, P.L., Kilburn, K.H., 1981. California Society for Histotechnology, Los Angeles, CA, Health Hazard Evaluation Report, (NIOSH Report No. HETA 81-422-1387), Cincinnati, OH, US Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health.

Bolt, H.M., Johnson, G., Nielsen, G.D., Papameletiou, D., Klein, C.L., 2016. SCOEL/REC/ 125 Formaldehyde Recommendation from the Scientific Committee on Occupational Exposure Limits. Adopted 30 June 2016. Publications Office of the European Union, Luxembourg.

Brickus, L.S.R., Cardoso, J.N., Aquino Neto, F.R., 1998. Distributions of indoor and outdoor air pollutants in Rio de Janeiro, Brazil: Implications to indoor air quality in bayside offices. Environ. Sci. Technol., 32, 3485–3490.

Bruinen De Bruin, Y., Koistinen, K., Kephalopoulos, S., Geiss, O., Tirendi, S., Kotzias, D., 2008. Characterisation of urban inhalation exposures to benzene, formaldehyde and acetaldehyde in the European Union: comparison of measured and modelled exposure data. Environ. Sci. Pollut. Res., 15 (5): 417-430.

CAREX, 1999. Carex industry specific estimates – Summary. Available at

Chang, C.J., Cheng, S.F., Chang, P.T., Tsai, S.W., 2018. Indoor air quality in hairdressing salons in Taipei. Indoor Air; 28 (1): 173-180.

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.

EN 482, Workplace exposure - General requirements for the performance of procedures for the measurement of chemical agents, European Committee for Standardization, Bruxelles, 2015.

EN 689, Workplace atmospheres. Guidance for the assessment of exposure by inhalation to chemical agents for comparison with limit values and measurement strategy, European Committee for Standardization, Bruxelles, 1997.

Environment Canada, 1997 a. Results of the CEPA Section 16 Notice to Industry respecting the second Priority Substances List and di(2-ethylhexyl) phthalate. Hull, Quebec, Environment Canada, Commercial Chemicals Evaluation Branch, Use Patterns Section.

Environment Canada, 1997 b. VOC emissions survey of adhesives, sealants and adhesive tape manufacturers in Canada. Draft report prepared for Pollution Data Branch, Environment Canada, Hull, Quebec.

Environment Canada, 1997 c. Notice respecting the second Priority Substances List and di(2-ethylhexyl) phthalate. In Canada Gazette, Part I, 15 February 1997, 366–368.

Environment Canada, 1999. Canadian Environmental Protection Act — Priority Substances List — Supporting document for the environmental assessment of formaldehyde. Hull, Quebec, Environment Canada, Commercial Chemicals Evaluation Branch.

European Chemical Industry Council (CEFIC). The EU formaldehyde market. Brussels: Formcare, 2009.

Fantuzzi, G., Aggazzotti, G., Righi, E., Cavazzuti, L., Predieri, G., Franceschelli, A., 1996. Indoor air quality in the university libraries of Modena (Italy). Sci. Total Environ., 13; 193 (1): 49-56.

Fisher, P.W., Foster, J.A., Deb, K.., 1991. Development of toxic air pollutant emissions for thirteen pulp and paper mills in Wisconsin. In: TAPPI Proceedings 1991 Environmental Conference. Atlanta, GA, Technical Association of the Pulp and Paper Industry, 469–481.

Fuselli, S., Zanetti, C., 2006. Formaldeide in aria di ambienti interni ed esterni di un’area urbana, in relazione all’esposizione dell’uomo. Ann. Ist. Super. Sanità 42 (3): 365-8.

Heikkilä, P., Priha, E., Savela, A., 1991. Formaldehyde. Exposures at Work No. 14. Helsinki, Finnish Institute of Occupational Health and Finnish Work Environment Fund.

Howard, P.H., in Handbook of environmental fate and exposure data for organic chemicals. Vol. 1. Large production and priority pollutants. Chelsea, MI, Lewis Publishers, 1989.

I.P.C.S., Formaldehyde. Geneva, World Health Organization, International Programme on Chemical Safety. Environmental Health Criteria 89, 1989.

IARC, 1981. Wood, leather and some associated industries. IARC Monographs on the Evaluation of Carcinogenic Risk of Chemicals to Humans, Volume 25, Lyon, International Agency for Research on Cancer, 1–412.

IARC, 2006. Formaldehyde, 2-butoxyethanol and 1-tertbutoxypropan- 2-ol. IARC Monographs on the evaluation of carcinogenic risk of chemicals to humans, Volume 88, Lyon, International Agency for Research on Cancer, 1–478.

IARC, 2012. Chemical agents and related occupations. IARC Monographs on the evaluation of carcinogenic risk to humans, Volume 100F, Lyon, International Agency for Research on Cancer, 401–436.

ISO 16000-4, Indoor air — Part 4: Determination of formaldehyde — Diffusive sampling method, International Organization for Standardization, 2011.

Jermini, C., Weber, A., Grandjean, E., 1976. Quantitative determination of various gas-phase components of the side-stream smoke of cigarettes in the room air as a contribution to the problem of passive smoking. Int. Arch. Occup. Env. Health, 36: 169–181.

Kauppinen, T., Toikkanen, J., Pedersen, D., Young, R., Ahrens, W., Boffetta, P., Hansen, J., Kromhout, H., Blasco, J.M., Mirabelli, D., de la Orden-Rivera, V., Pannett, B., Plato, N., Savela, A., Vincent, R., Kogevinas, M., 2000. Occupational exposure to carcinogens in the European Union. Occup. Environ. Med., 57: 10–18.

Kelly, T.J., Smith, D.L., Satola, J., 1999. Emission rates of formaldehyde from materials and consumer products found in California homes. Environmental Science & Technology. 33: 81–88.

Kitchens, J.F., Casner, R.E., Edwards, G.S., Harward, W.E., Macri, B.J., in Investigation of selected potential environmental contaminants: formaldehyde. Washington, DC, US Environmental Protection Agency, 1976.

Kotzias, D., Geiss, O., Tirendi, S., 2005. Valutazione dell’esposizione totale a benzene e formaldeide nei paesi europei. Epidemiol. Prev., 29 (5-6 Suppl): 17-21.

Kromhout, H., 2016. Hygiene without numbers. Ann. Occup. Hyg., 60 (4): 403-4.

Lange, J.H., Harrison, R.M., 1998. Evaluation of personal exposure to monoaromatic hydrocarbons. Occup. Environ. Med., 55: 249–257.

Lange, J.H., Kuhn, B.D., Thomulka, K.W., 2000. A study of matched area and personal airborne asbestos samples: evaluation for relationship and distribution. Indoor and Built Environment, 9: 192–200.

Lipari, F., Dasch, J.M., Scruggs, W.F., 1984. Aldehyde emissions from wood-burning fireplaces. Environ. Sci. Technol., 18: 326–330.

Mandin, C., Trentallidi, M., Cattaneo, A., Canha, N., Mihucz, VG., Szigeti, T., Mabilia, R., Perreca, E., Spinazzè, A., Fossati, S., De Kluizenaar, Y., Cornelissen, E., Sakellaris, I., Saraga, D., Hanninen, O., De Oliveira Fernandes, E., Ventura, G., Wolkoff, P., Carrer, P., Bartzis, J., 2017 Assessment of indoor air quality in office buildings across Europe – The OFFICAIR study. Sci Total Environ. Sci Total Environ 1; 579; 169-178.

Maneli, M.H., Smith, P., Khumalo, N.P., 2014. Elevated formaldehyde concentration in "Brazilian keratin type" hair-straightening products: a cross-sectional study. J. Am. Acad. Dermatol., 70 (2):276-80.

Miguel, A.H., De Aquino Neto, F.R., Cardoso, J.N., Vasconcellos, P.C., Pereira, A.S., Marquez, K.S.G., 1995. Characterization of indoor air quality in the cities of São Paulo and Rio de Janeiro, Brazil. Environ. Sci. Technol., 29, 338–345.

Mirabelli, D., Kauppinen, T., 2005. Occupational exposures to carcinogens in Italy: an update of CAREX database. Int. J. Occup. Environ. Health. 11 (1): 53-63.

Mundt, K.A., Robinan Gentry, P., Dell, L.D., Rodricks, J.V., Boffetta, P., 2018. Six years after the NRC review of EPA's Draft IRIS Toxicological Review of Formaldehyde: Regulatory implications of new science in evaluating formaldehyde leukemogenicity. Regulatory Toxicology and Pharmacology 92, 472–490.

National Toxicology Program (NTP). Report on carcinogens, Twelfth Edition: Formaldehyde. Research Triangle Park, NC: U.S. Department of Health and Human Services, Public Health Service, 2011.

Nielsen, G.D., Wolkoff, P., 2010. Cancer effects of formaldehyde: a proposal for an indoor air guideline value. Arch. Toxicol., 84 (6): 423-46.

Nielsen, G.D., Larsen, S.T., Wolkoff, P., 2013. Recent trends in risk assessment of formaldehyde exposures from indoor air. Arch. Toxicol., 87 (1): 73-98.

Nielsen, G.D., Larsen, S.T., Wolkoff, P., 2017. Re-evaluation of the WHO (2010) formaldehyde indoor air quality guideline for cancer risk assessment. Arch. Toxicol., 91 (1): 35-61.

NIOSH, Manual of Analytical Methods (NMAM), Fourth Edition. Method: 2016, Formaldehyde. Issue 2, Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH), 2003.

O’Connor, B., Voss, R., 1997. Guidance with respect to PSL2 survey. Pointe-Claire, Quebec, Pulp and Paper Research Institute of Canada.

Peteffi, G.P., da Silva L.B., Antunes M.V., Wilhelm, C., Valandro, E.T., Glaeser, J., kaefer, D., Linden, R., 2016. Evaluation of genotoxicity in workers exposed to low levels of formaldehyde in a furniture manufacturing plant. Toxicol. Ind. Health,, 31 (10): 1763-76.

Peteffi, G.P., Antunes, M.V., Carrer, C., Valandro, E.T., Santos, S., Glaeser, J., Mattos, L., da Silva L.B., Linden, R., 2016. Environmental and biological monitoring of occupational formaldehyde exposure resulting from the use of products for hair straightening. Environ. Sci. Pollut. Res. Int., 23 (1): 908-17.

Peters, C.E., Ge, C.B., Hall, A.L. Davies, H.W., Demers, P.A., 2015. CAREX Canada: an enhanced model for assessing occupational carcinogen exposure. Occup. Environ. Med., 72: 64–71.

Proietti, L., Fantauzzo, R., Gulino, S., Trizzino, M., Longo, B., Duscio, D., 2004. Risultati di una indagine sull’inquinamento da formaldeide responsabile di malessere negli impiegati di alcuni uffici pubblici. Ig. Sanità Pubbl. 60: 219-227.

Ramdahl, T., Alfheim, I., Rustad, S., Olsen, T., 1982. Chemical and biological characterization of emissions from small residential stove burning wood and charcoal. Chemosphere, 11 (4): 601–611.

Reinhardt, T.E.. Monitoring firefighter exposure to air toxins at prescribed burns of forest and range biomass. Portland, OR, US Department of Agriculture, Forest Service, Pacific Northwest Research Station, 1991.

Righi, E., Aggazzotti, G., Fantuzzi, G., Ciccarese, V., Predieri, G., 2002. Air quality and well-being perception in subjects attending university libraries in Modena (Italy). Sci. Total Environ., 286, 41-50.

Rosén, G., Bergström, B. & Ekholm, U., 1984. Occupational exposure to formaldehyde in Sweden. Arbete Hälsa, 50, 16–21.

Rovira J, Roig N, Nadal M, Schuhmacher M, Domingo JL, 2015 Human health risks of formaldehyde indoor levels: An issue of concern. J Environ Sci Health. 51 (4), 257-63.

Salthammer, T., Mentese, S., Marutzky, R., 2010. Formaldehyde in the indoor environment. Chemical Reviews. 110: 2536–2572.

Scarselli, A., Corfiati, M., Di Marzio, D., Iavicoli, S., 2017. National Estimates of Exposure to Formaldehyde in Italian Workplaces. Annals of Work Exposures and Health, Vol. 61 (1), 33–43.

Shah, J.J., Singh, H.B., 1988. Distribution of volatile organic chemicals in outdoor and indoor air. A national VOCs data base. Environ. Sci. Technol., 22, 1381–1388.

Stewart, P.A., Cubit, D.A., Blair, A., 1987. Formaldehyde levels in seven industries. Appl. Ind. Hyg., 2, 231–236.

Stopponi, R., Astuti M.C., Mattozzi, C., 2014 Allevatori avicoli ed esposizione professionale a formaldeide. Med. Lav., 105(3), 234.

Tsigonia, A., Lagoudi, A., Chandrinou, S,, Linos, A., Evlogias, N., Alexopoulos, E.C., 2010. Indoor air in beauty salons and occupational health exposure of cosmetologists to chemical substances. Int. J. Environ. Res. Public Health, 7 (1): 314-24.

US EPA. Evaluation of emission factors for formaldehyde from certain wood processing operations. Final report, May–August 1989. Research Triangle Park, NC, US Environmental Protection Agency, Office of Research and Development, Air and Energy Engineering Research Laboratory (EPA/600/8-90/052), 1990.

US EPA. Motor vehicle-related air toxics study. Ann Arbor, MI, US Environmental Protection Agency, Office of Mobile Sources, Emission Planning and Strategies Division, April (EPA 420-R-93-005), 1993.

Walker, B.L., Cooper, C.D., 1992. Air pollution emission factors for medical waste incinerators. J. Air Waste Manag. Assoc., 42: 784–791.

WHO, 2002. Formaldehyde: Concise International Chemical Assessment Document 40, World Health Organization.

WHO, 2010. WHO Guidelines for Indoor Air Quality: Selected Pollutants, Copenhagen, WHO Regional Office for Europe, ISBN 978 92 890 0213 4: 103-156.

Wieslander, G., Norbäck, D., Wålinder, R., Erwall, C., Venge, P., 1999. Inflammation markers in nasal lavage, and nasal symptoms in relation to relocation to a newly painted building: A longitudinal study. Int. Arch. Occup. Environ. Health, 72, 507–515.

Wu, P.C., Li, Y.Y., Lee, C.C., Chiang, C.M., Su, H.J.J., 2003. Risk assessment of formaldehyde in typical office buildings in Taiwan. Indoor Air, 13, 359–363.


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