Assessment of Flame Retardant Exposure Pathways in Households in the UK

Supervisors:

• Professor Anna Hansell
• Dr Rebecca Cordell

Project Description:

Flame retardants (FRs) are a diverse group of chemicals widely used since the 1970s in consumer products like furniture, textiles, electronics, and building materials to reduce flammability. Many of the early generation flame retardants e.g., polychlorinated biphenyls (PCBs), and more recently most polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane isomers (HBCDD) have been banned owing to their environment persistence, potential for bioaccumulation and deleterious health effects. Despite this legislation these compounds reside within the environment and are continued to be emitted from older products and waste recycling/incineration facilities. 

Successive generations of FRs including organic phosphorus FRs (OPFRs) and novel brominated FRs (NBFRs) have been introduced to replace their banned predecessors, however, evidence is mounting that the bioaccumulation and health effects of the banned FRs are also common issues with the replacement compounds. Many of these chemicals can accumulate in indoor air, dust, and on surfaces, leading to the possibility of inhalation and dermal exposure within the domestic environment. Previous studies have primarily focused on exposure in specific regions or industries, but there is limited data on how flame retardants, particularly the new generation products, disperse and accumulate in the home. Despite the fact the UK has some of the highest use of flame retardants in the world only a small number of studies in the UK have looked at FR exposure from the indoor environment within the general population.

This research aims to assess and quantify the exposure of individuals to FRs by measuring levels of FRs and their metabolites in urine samples. The study will also examine the levels of FRs in and around volunteers’ homes, by measuring air, dust, soil, and surface contamination to understand exposure routes. The project will review data from past studies on older FRs to evaluate how exposure profiles have changed over time with new legislation and regulations to determine whether government policy has successfully reduced exposure risks.

The work will be carried out in synergy with personnel at UKHSA and the PhD the student will spend time in UKHSA’s analytical laboratories and take part in a laboratory inter-comparison study.

PhD Objectives:

Quantification of FRs 
Apply state-of-the-art two-dimensional gas chromatography – mass spectrometry (GCxGC-MS) to quantify the levels of FRs in various environmental samples (e.g., indoor air, dust, outdoor air and soil) and in human urine, which will be measured at UKHSA and UoL labs as part of a laboratory comparison.

Examine variability in FR Concentrations  
Investigate the variability of FR concentrations across different homes, examining physical factors such as geography, building age, and the presence of specific flame-retarded materials or products, alongside sociodemographic factors. 

Evaluate exposure pathways
Evaluate potential exposure routes from air and dust, assessing the relationship between concentrations in air, dust, and within urine. 

Engage with policy
Collaborate with UKHSA on how to review existing data from previous studies and how it can, alongside data from this new study and further studies, contribute to evidence-based public health recommendations.

Comprehensive data on the concentrations of FRs in indoor air, dust, and outdoor air in UK households, highlighting potential sources of exposure.

Data on personal exposure levels to FRs, as measured through urine samples, to better understand individual exposure levels in the population.

Identification of key sources of flame retardants in homes, including specific materials and products, as well as factors influencing their distribution in indoor and outdoor environments.

Evidence-based recommendations for reducing FR exposure in residential environments, guiding policy makers, industry stakeholders, and the public on effective measures for risk reduction.

The National Institute for Health and Care Research (NIHR) Health Protection Research Unit (HPRU) in Chemical Threats and Hazards is based at the University of Leicester and is a partnership between the University, the UK Health Security Agency (UKHSA) and the Health and Safety Executive (HSE). As part of the HPRU, students will benefit from co-supervision and placements at least one of UKHSA or HSE. The HPRU in Chemical Threats and Hazards is dedicated to career development, and all students will receive tailored training and will be engaged with Patient and Public Involvement (PPI) and Research Inclusion.

Please refer to the How to Apply section below before applying. Download and complete the Widening Participation Form and upload to your online application.