Toxic inhalation surveillance

Chemical and biological hazards in the workplace have the potential to cause adverse health effects such as breathing problems, burns, skin disease, and cancer. Workplace air sampling data collected by L&I’s compliance officers and workers’ compensation data are used to identify trends in exposure, injury and illness. We work with employers, workers, and trade associations to identify and test best practices to eliminate or reduce harmful exposures.

Toxic Inhalation Surveillance

Toxic inhalation refers to an inhalation exposure of vapor, gas, dust or fume that may result in an adverse health effect. The exposure may be a one-time event or ongoing from daily processes. The health effects may be immediate or they may develop over time. Exposure to the following compounds are tracked through SHARP’s surveillance system on an ongoing systematic process: ammonia, beryllium, carbon monoxide, chlorine, chromium, metal fume, methylene chloride, and wildland smoke. The data source for SHARP’s toxic inhalation system is workers’ compensation claims, beginning with the year 2017.  Please see the Journal Article and Technical Reports tab on this page for detailed technical reports that summarize the toxic inhalation surveillance system.

Exposure surveillance

Airborne exposures to chemical substances and noise are routinely documented through personal airborne chemical sampling conducted by Labor and Industries’ Division of Occupational Safety and Health (DOSH). In addition to supporting DOSH’s mission, these exposure samples provide insight into the hazards faced by workers. Such hazards include both well-known and emerging hazards in either known or novel applications.

The purpose of exposure surveillance is to describe the trends for airborne exposures, to make comparisons among industries and occupations, and to identify opportunities for exposure prevention activities.

Research Topics

Research Topics

Methylene Chloride used in bathtub refinishing

Carbon Monoxide poisoning from forklifts

Isocyanate exposure in collision repair painters

Exposure to food flavorings and lung disease

Methylene Chloride used in bathtub refinishing

Methylene chloride, also known as dichloromethane, is an industrial solvent and effective paint stripper. It is found in both industrial and consumer products and has extensive OSHA safety regulations.

The deaths of at least 17 bathtub refinishers have been attributed to methylene chloride exposure, a key ingredient in paint stripper. Thirteen of the deaths are profiled across 10 states between 2000 and 2011, with some of these deaths resulting from less than 90 minutes of exposure to methylene chloride. Methylene chloride is highly volatile and easy to inhale, with vapors that are heavier than air. As a result, the vapors sink and collect low inside the bathtub where the refinisher is working and breathing. Additionally, bathtub refinishers often work alone in small bathroom spaces with limited or no ventilation. Methylene chloride’s heavier-than-air chemical properties, it’s toxicity, and the working conditions combine to make bathtub refinishing with methylene chloride -based products a very hazardous task. Beyond the immediate fatal health effects, long-term health effects from exposure to methylene chloride include cancer, depression of respiratory function, and central nervous system damage. Additional effects include skin burns and skin irritation.

While ventilation and personal protective equipment can reduce a worker’s risks when used correctly, some experts argue that methylene chloride-based strippers cannot be used safely under the conditions bathtub refinishers work under. In the European Union, the use of methylene chloride-based paint strippers outside of a controlled industrial setting were banned in 2009. To identify whether your product contains methylene chloride (CAS number 75-09-2), review the product’s Safety Data Sheet or active ingredients on the product label.

Alternatives to methylene chloride-based paint strippers

SHARP has profiled two businesses who use safer alternatives to methylene chloride-based paint strippers. One business successfully uses a benzyl alcohol-based chemical stripper and the other relies on mechanical scraping and sanding for finish removal. Be aware that some alternative products advertised as “safer” still contain hazardous substances, such as N-methylpyrrolidone (NMP), a known reproductive hazard. Products containing NMP are not recommended. All chemicals in paint stripping and refinishing have hazards, be sure to read the product’s Material Safety Data Sheet (MSDS).

See the Prevention Resources tab for educational resources on this topic.

Additional Resources:

Carbon Monoxide poisoning from forklifts

Carbon monoxide is produced by the incomplete combustion of carbon-containing fuels. All combustion engines produce exhaust emissions that can contain harmful levels of carbon monoxide. Emission sources are vehicles, portable fuel-burning saws, generators, heaters, furnaces, power washers, insulation blowers, man lifts, compressors, ovens, and floor buffers.

A review of workers’ compensation claims showed that poisonings can be caused by fuel-driven forklifts and occur frequently in Wholesale Trade, Agriculture, Manufacturing, and Transportation. The risk of carbon monoxide poisoning is higher with older forklifts whose engines were manufactured before 2004 and with forklifts used inside enclosed spaces such as cold rooms, controlled atmosphere rooms, refrigerated warehouses, and other non-ventilated spaces. Even when used indoors with ventilation, fuel-driven forklifts can still pose a risk because poisoning can occur at very low concentrations. We recommend routine, in-house forklift emission testing of propane-powered forklifts. Emission testing can save fuel costs as well as reduce the risk of poisonings.

Carbon monoxide poisoning can be severe or even fatal, can involve large numbers of workers in a single incident, and may result in production delays. You cannot smell, see or taste carbon monoxide. The early symptoms of carbon monoxide poising are flu-like and nonspecific such as headache, nausea, dizziness, visual disturbances, and rapid breathing.

See the Prevention Resources tab for educational resources on this topic.

Isocyanate exposure in collision repair painters

Collision repair painters are potentially exposed to a wide range of harmful substances while prepping and painting vehicles such as airborne particles, solvents, and paint pigments. Most two-part paints and coatings used in automotive refinishing include an isocyanate-based catalyst or hardener.

Painters are at risk for developing work-related asthma from exposure to isocyanates. Asthma is a disease that affects the lungs and makes it increasingly hard to breathe. Workers who develop asthma may need to stop working with automotive paints or leave their job.

New information suggests that isocyanates can cause asthma through breathing as well as through skin contact. Workers may absorb isocyanates through their skin if they use bare hands to mix paint, shoot paint, or clean up spills. Isocyanates may also be absorbed through the skin at the neck, wrists and on the face during painting.

We recommend ventilated spray booths and that all automotive spray painters wear an air-purifying respirator to protect their lungs. We recommend 9 millimeter (ml) thick (or thicker) nitrile gloves and shoot suits be worn during painting. Latex gloves do not protect against isocyanates.

Do the paints you use contain isocyanates?

Any two-part polyurethane coating (primer, basecoat or clearcoat) will likely contain isocyanates. The isocyanates are formulated into the hardener or catalyst. If you are unsure if you are using isocyanate containing paint systems, refer to your product Safety Data Sheets (SDS). The most common isocyanate used in auto refinish coating systems is hexamethylene diisocyanate (HDI). Other isocyanates that may be used are 2,4-toluene diisocyanate (TDI), 4,4'-diphenyl methane diisocyanate (MDI); and isophorone diisocyanate (IPDI).

See the Prevention Resources tab for educational resources on this topic.

Exposure to food flavorings and lung disease

Food flavorings are a mixture of compounds that may include a chemical called diacetyl (also known as 2,3-Butanedione). Diacetyl imparts a buttery taste to food. It is naturally present at low concentrations in a wide variety of foods such as dairy, beer, coffee, honey and fruits. There is increasing scientific evidence that links diacetyl exposure to a severe form of lung disease called bronchiolitis obliterans. It is not clear whether diacetyl exposure alone is capable of causing disease, or whether diacetyl along with mixtures of volatile organic compounds result in disease. While much is unknown regarding the toxicity of food flavorings and diacetyl, steps can be taken in the workplace to reduce employee exposure to these chemicals.

In food manufacturing, diacetyl is added to a wide range of foods. Examples include: butter, cheese, milk, flour mixes, cookies, crackers, chips, candy and confectionery products, chocolate and cocoa products, flavored and unflavored coffee, shortening and food oils, flavored syrups, ready-mix and gelatin desserts, and prepared frosting. People who make or work near flavorings in the production and packaging of food may be at risk for diacetyl exposure in the form of vapors, dusts or sprays.

To identify whether diacetyl is in the materials you may be handling, check container labels and product Safety Data Sheets (SDS). Diacetyl has the Chemical Abstract Service (CAS) number 431 03 8 and should be listed in Section 2 of the SDS. However, because diacetyl is often present in low quantities, it may not be specifically listed on the SDS sheet.

See the Prevention Resources tab for educational resources on this topic.

Prevention Resources Journal Articles & Technical Reports

Technical Reports:

Occupational toxic inhalation of carbon monoxide among Washington workers, 2017 – 2022. This report summarizes the carbon monoxide surveillance methods and describes trends in exposures for 2017-2022 by industry, occupation, and source.

Surveillance of Toxic Inhalation for Washington Workers, 2017 - 2020.  This report summarizes 2604 inhalation cases; the data can be used to identify patterns in hazardous workplace exposures and identify the industries and occupations where prevention work is needed.

Supplementary Report: Methods and evaluation for Washington State's toxic inhalation surveillance system, 2017 - 2020.  This report describes and evaluates the case-capture methods used in the  surveillance system.

Appendix Tables: Surveillance of Toxic Inhalation for Washington Workers, 2017 - 2020.  Includes 47 data tables that characterize toxic inhalations by industry and occupation.

Industrial Hygiene Exposure Assessment Measurements in Washington State, 2008 - 2016. This report characterizes airborne personal exposure monitoring for chemicals and noise, by industry and exposure severity.

Health and Safety in Washington State's Collision Repair Industry: A Needs Assessment

Journal Articles:

Reeb-Whitaker CK, Eckert C, Anderson NJ, and Bonauto DK (2015). Occupational hydroflouric acid injury from car and truck washing - Washington, 2001 - 2013. Center for Disease Control, Morbidity and Mortality Weekly Report (MMWR), 64(32): 874-877. Research Finding

Lofgren DJ, Reeb-Whitaker CK, and Adams D (2010). Surveillance of Washington OSHA exposure data to identify uncharacterized or emerging occupational health hazards. Journal of Occupational and Environmental Hygiene DOI: 10.1080/15459621003781207.

Reeb-Whitaker CK, Bonauto DK, Whittaker SG, and Adams D (2010). Occupational carbon monoxide poisoning in Washington State, 2000-2005. Journal of Occupational and Environmental Hygiene DOI: 10.1080/15459624.2010.488210.

Reeb-Whitaker C, Anderson NJ, and Bonauto DK (2013) Prevention Guidance for Isocyanate-Induced Asthma Using Occupational Surveillance Data. Journal of Occupational & Environmental Hygiene DOI: /10.1080/15459624.2013.818236 | Research Finding

Reeb-Whitaker C, Whittaker SG, Ceballos DM, Weiland EC, Flack SL, Fent KW, Thomasen JM, Trelles Gaines LG, and Nylander-French LA (2012). Airborne isocyanate exposures in the collision repair industry and a comparison to occupational exposure limits. Journal of Occupational and Environmental Hygiene DOI: 10.1080/15459624.2012.672871 | Research Finding

Ceballos DM, Whittaker SG, Yost MG, Dills RL, Bello D, Thomasen JM, Nylander-French LA, Reeb-Whitaker CK, Peters PM, Weiland EC, and Suydam WW (2011). A laboratory comparison of analytical methods used for isocyanates. Analytical Methods DOI: 10.1039/c1ay05225j.

Ceballos DM, Yost MG, Whittaker SG, Reeb-Whitaker C, Camp J, and Dills R (2011). Development of a permeation panel to test dermal protective clothing against sprayed coatings. Annals of Occupational Hygiene https://academic.oup.com/annweh/article/55/2/214/476734.

Ceballos DM, Yost MG, Whittaker SG, Camp J, and Dills R (2009). Objective color scale for the SWYPE surface sampling technique using computerized image analysis tools. Journal of Occupational and Environmental Hygiene DOI: 10.1080/15459620903117710.

Ceballos D. Reeb-Whitaker C, Glazer P, Murphy-Robinson H, and Yost M (2014). Understanding factors that influence protective glove use among automotive spray painters. Journal of Occupational Environmental Hygiene DOI: 10.1080/15459624.2013.862592.

Ceballos DM, Fent KW, Whittaker SG, Gaines LGT, Thomasen JM, Flack SL, Nylander-French LA, Yost MG, and Reeb-Whitaker CK (2011). Survey of dermal protection in Washington State collision repair industry. Journal of Occupational and Environmental Hygiene DOI: 10.1080/15459624.2011.602623.

Whittaker SG, and Reeb-Whitaker C (2009). Characterizing the health and safety needs of the collision repair industry. Journal of Occupational and Environmental Hygiene DOI: 10.1080/15459620902775609.