Assessing new methods for measuring occupational exposure to flame retardants

Status: The study is currently recruiting participants.


The goal of this study is to explore two new methods for measuring occupational exposure to flame retardants:

  1. Simple silicone wristbands to passively sample flame retardant levels in workplace air; and
  2. High resolution metabolomics to measure levels of flame retardants and their metabolites within the body.

The study will investigate if these methods can determine whether workers have been occupationally exposed to flame retardants, and if they can identify changes in workers’ exposure to flame retardants over time.


Flame retardants are chemicals incorporated into many consumer products, such as electronics and home furnishings, in order to meet fire safety standards. Flame retardants can be released from these products and enter the surrounding environment. People may be exposed at home or at work, by breathing in, touching, or ingesting flame retardants. Flame retardants have been associated with a variety of health effects, including cancer, but there is little information on what levels of exposure are hazardous, in part because we lack reliable and easy to use methods for measuring these chemicals.

Valid and reliable methods for identifying occupational exposure are needed to better understand the impact of chemicals such as flame retardants on the development of cancer and other disease. Traditional sampling methods are effective, but can often be impractical. For example, measuring levels of chemicals in the air often requires sampling equipment that is expensive, disruptive to wear and difficult to set up. Advancements in technology are making it possible to measure exposures using simple samplers such as silicone wristbands, or by monitoring levels of contaminants and their metabolites inside the body (metabolomics). These new technologies can be used to estimate external and internal exposures for large and diverse worker groups, and offer innovative alternatives to traditional sampling methods if they can be validated.


The study will include firefighters (who are expected to have high levels of flame retardant exposure), and office workers (who are expected to have low levels of exposure). Participants will be asked to wear wristbands made of polydimethylsiloxane (PDMS), a type of silicone rubber, for three days. Participants will also provide blood and urine samples at the beginning and end of the sampling period. The silicone wristbands and biological samples will be analyzed in a laboratory to determine levels of exposure to flame retardants. The biological samples will be analyzed using novel high resolution metabolomics methods, and the results from all samples will be compared to more traditional methods of measuring flame retardant chemicals in biological samples in order to validate the new methods.

Participants will also fill out questionnaires about their work in order to better understand their risk factors and the tasks or products that may be associated with exposure to flame retardants.


This study will provide information on the validity of two new methods for assessing exposure to flame retardants. The results will tell us whether these methods may be useful for measuring chemical exposures in larger, future studies of workers or the general population. If validated, these methods could also allow researchers to leverage large existing cohorts to investigate occupational exposures and their relationship to disease.

This study will also provide information on the level of exposure to flame retardants among firefighters and office workers, and the types of tasks that increase the risk of exposure. This information may be useful in targeting prevention efforts among exposed workers.

Although the focus of the current study was exposure to flame retardants, many of the laboratory analyses conducted as part of this study are “untargeted,” meaning that the results can be used to identify a wide range of chemicals. Thus, the innovative methods developed for this study have the potential to be used to assess exposure to a wide variety of potentially toxic exposures at relatively little or no additional costs.

Progress (updated March 2021):

We have collected samples from 20 of 40 firefighters. In 2022, we hope to recruit the remaining participants (20 firefighters, 20 paramedics and 20 office workers) and complete sample collection.


This project is funded by a Prevention Innovation Grant from the Canadian Cancer Society (award #705577).


Toronto Fire Services
Toronto Professional Fire Fighters’ Association

Research Team:

Joseph Okeme
Sheila Kalenge
Paul Demers
Victoria Arrandale
Yizhi Zhang (University of Toronto)
Miriam Diamond (University of Toronto)
Philip Awadalla (Ontario Institute for Cancer Research)
Roel Vermeulen (Utrecht University)
Nikhil Rajaram (University of Toronto & MLTSD)
Douglas Walker (Mt Sinai Health System, New York)
Lia Alderete (Life Labs)