Firefighters are exposed to a wide range of chemicals whilst on duty, including polycyclic aromatic hydrocarbons (PAHs), organophosphate flame-retardants (OPFRs), and polybrominated diphenyl ethers ...(PBDEs). These groups of chemicals are related to combustion emissions. PAHs are formed during combustion. OPFRs and PBDEs are flame-retardants and are inadvertently released during combustion. Exposure to these chemicals occurs when attending fire scenes, and firefighters can track these chemicals back into fire stations leading to further exposure. The objective of this study was to understand the concentrations of PAHs, OPFRs, and PBDEs in fire stations, to evaluate factors that affect chemical concentration, and to assess how air and dust could contribute to firefighters' relevant exposure risk. Concentrations of 13 PAHs, 9 OPFRs, and 8 PBDEs were quantified in fire station dust (n = 49) and air (n = 15) samples collected between November 2017 and February 2018. The median ∑
13
PAH concentration was 15 ng m
−3
and 3.1 µg g
−1
in air and dust, respectively, while the median ∑
9
OPFR concentration was 56 ng m
−3
in air and 84 µg g
−1
in dust, and ∑
8
PBDE had a median concentration of 0.78 ng m
−3
in air and 26 µg g
−1
in dust. The estimated daily intakes through dust and air for ∑
13
PAHs, ∑
9
OPFRs, and ∑
8
PBDEs in firefighters were 3.6, 17, and 1.6 ng (kg body weight)
−1
day
−1
, respectively. The worst-case estimated daily intakes were only 2% of the reference dose for individual chemicals. Pearson's correlations with chemical concentration for several PAHs, OPFRs, and PBDEs were found between the number of years since fire stations were last renovated, as well as the storage locations of firefighting ensembles. These results suggest chemicals are brought back to fire stations from fire scenes and that they are accumulating in fire stations. They also suggest soiled firefighting ensembles are a source of these chemicals in fire stations and that their proximity to the rest of the station determines the extent to which they contribute to chemical concentrations in fire stations.
Paired indoor air and floor dust samples were collected from residential houses and offices (n = 28) in two Australian cities in 2015. For the air samples, a modified passive air sampler (PAS) was ...used to collect semi-volatile organic compounds (SVOCs) in gaseous phase and airborne particles simultaneously. Sampling rates (R) of the PAS for gaseous SVOCs ranged from 0.69 to 3.4 m3 sampler−1 day−1. Out of the 33 analytes, 22, 14 and 17 compounds were detected (above the method detection limit) in over 50% of air, airborne particles and floor dust samples respectively. The highest median level in air, airborne particles and floor dust was observed for phenanthrene (2.0 ng m−3), permethrin (8800 ng g−1) and permethrin (5100 ng g−1) respectively. Among polychlorinated biphenyl (PCB) congeners, with few exceptions, the largest contribution was from 3,3′-dichlorobiphenyl (PCB11) for both indoor air and floor dust samples. In these houses and offices, the indoor level of polycyclic aromatic hydrocarbons (PAHs) was mainly influenced by ambient (outdoor) air. Primary sources of PCBs were from within indoor environments and generally older houses have higher concentrations in air. Among pesticides, hexachlorobenzene in indoor environments appeared to be due to transfer from outdoor sources whereas chlordanes and pyrethroids were associated with past and current household application respectively. Compared to data from other countries/regions, concentrations of chlordanes, chlorpyrifos and pyrethroids in indoor air and dust samples from Australia were among the highest whereas PCB and PAH levels were among the lowest. The sum of estimated daily intakes (EDIs) via inhalation and dust contact and ingestion were calculated. The highest median value of EDI was observed for permethrin at 2.8 (for adults) and 74 ng kg−1 day−1 (for toddlers), which are <0.15% of the U.S. EPA reference dose.
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•A modified PAS was used to simultaneously collect gaseous SVOCs and particles.•PCB 11 was identified and quantified in indoor environments for the first time.•PCBs and pesticides were from indoor while PAHs were influenced by outdoor sources.•Indoor pesticide levels in Australia were among the highest in the world.•The highest EDI value was estimated for permethrin, mostly via exposure to dust.
A key uncertainty of wastewater-based epidemiology is the size of the population which contributed to a given wastewater sample. We previously developed and validated a Bayesian inference model to ...estimate population size based on 14 population markers which: (1) are easily measured and (2) have mass loads which correlate with population size. However, the potential uncertainty of the model prediction due to in-sewer degradation of these markers was not evaluated. In this study, we addressed this gap by testing their stability under sewer conditions and assessed whether degradation impacts the model estimates. Five markers, which formed the core of our model, were stable in the sewers while the others were not. Our evaluation showed that the presence of unstable population markers in the model did not decrease the precision of the population estimates providing that stable markers such as acesulfame remained in the model. However, to achieve the minimum uncertainty in population estimates, we propose that the core markers to be included in population models for other sites should meet two additional criteria: (3) negligible degradation in wastewater to ensure the stability of chemicals during collection; and (4) < 10% in-sewer degradation could occur during the mean residence time of the sewer network.
Understanding the actual consumption of alcohol and tobacco in the population is important for forming public health policy. For this purpose, wastewater‐based epidemiology has been applied as a ...complementary method to estimate the overall alcohol and tobacco consumption in different communities. However, the stability of their consumption biomarkers – ethyl sulfate, ethyl glucuronide, cotinine, and trans‐3′‐hydroxycotinine – in the sewer system has not yet been assessed. This study aimed to conduct such assessment using sewer reactors mimicking conditions of rising main, gravity sewer, and wastewater alone, over a 12‐hour period. The results show that cotinine and trans‐3′‐hydroxycotinine are relatively stable under all sewer conditions while ethyl sulfate was only stable in wastewater alone and gradually degraded in rising main and gravity sewer conditions. Ethyl glucuronide quickly degraded in all reactors. These findings suggest that cotinine and trans‐3′‐hydroxycotinine are good biomarkers to estimate tobacco consumption; ethyl sulfate may be used as a biomarker to estimate alcohol consumption, but its in‐sewer loss should be accounted for in the calculation of consumption estimates. Ethyl glucuronide, and probably most of glucuronide compounds, are not suitable biomarkers to be used in wastewater‐based epidemiology due to their in‐sewer instability.
Tobacco consumption can be measured with high confidence through wastewater‐based epidemiology, as its biomarkers are stable in the sewer system while monitoring alcohol consumption is more difficult because its biomarkers degrade rapidly in‐sewer.
Wastewater contains a large range of biological and chemical markers of human activity and exposures. Through systematic collection and analysis of these markers within wastewater samples it is ...possible to measure the public health of whole populations. The analysis of effluent and biosolids can also be used to understand the release of chemicals from wastewater treatment plants into the environment. Wastewater analysis and comparison with catchment specific data (e.g. demographics) however remains largely unexplored. This manuscript describes a national wastewater monitoring study that combines influent, effluent and biosolids sampling with the Australian Census. An archiving program allows estimation of per capita exposure to and consumption of chemicals, public health information, as well as per capita release of chemicals into the environment. The paper discusses the study concept, critical steps in setting up a coordinated national approach and key logistical and other considerations with a focus on lessons learnt and future applications. The unique combination of archived samples, analytical data and associated census-derived population data will provide a baseline dataset that has wide and potentially increasing applications across many disciplines that include public health, epidemiology, criminology, toxicology and sociology.
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•Framework for national wastewater sampling to measure public and environment health•Aligned wastewater influent, effluent and biosolid sampling and archiving with census•Developed a questionnaire to characterise wastewater catchments and treatment plant processes•Defined recruitment strategies to achieve comprehensive population coverage•Matched census data will enhance interpretation of wastewater sample analysis.
Firefighter uniforms protect firefighters from exposure to potentially harmful chemicals including a range of semi-volatile organic compounds (SVOCs). Contaminated uniforms can become a secondary ...source of firefighters' exposure to these chemicals. There is inconsistency on the removal efficiency of SVOCs during the cleaning, laundering and field decontamination of firefighting uniforms. Therefore, this study aims to assess how effective decontamination and laundering processes are in reducing firefighter uniforms as a vector for transport and exposure to SVOCs. Firefighters who had attended a controlled house fire and simulated container burns had their uniforms sampled pre- and post-laundering. Clean station wear was laundered with contaminated uniforms and after a load of contaminated uniforms to assess inter and intra load contamination. Surface wipes were collected from uniforms across 12 fire stations, after they had returned from a laundering provider. Concentrations of 13 polycyclic aromatic hydrocarbons (PAHs), six organophosphate flame retardants (OPFRs) and seven polybrominated diphenyl ethers (PBDEs) were measured in the collected samples. The concentrations of ∑13 PAHs in firefighters uniforms ranged between 0.063 and 43 μg g−1, while concentration of ∑6 OPFRs were between 0.061 and 90 μg g−1 with ∑7 PBDEs concentrations being measured between 0.00054 and 0.97 μg g−1.The highest concentrations of ∑13 PAHs were measured on the outer layers of gloves at an average of 19 μg g−1, with the highest ∑6 OPFRs concentrations being measured in the middle layers of gloves at an average of 31 μg g−1. The highest ∑7 PBDEs concentrations were measured on the shell layers of turnout jackets at 0.42 μg g−1. The significant reduction in ∑13 PAHs after laundering or decontamination was only found in 3 of the 16 sampled areas from firefighting uniforms. No significant differences were found in the between pre- and post-laundering concentrations of ∑6 OPFRs or ∑7 PBDEs in firefighting uniforms. The current laundering techniques do not appear to effectively remove PAHs, OPFRs and PBDEs at the measured concentrations from firefighters’ uniforms. Further research is required to assess if chemical exposure though firefighting uniforms poses a health risk to firefighters and to develop methods for the removal of SVOCs from firefighting uniforms.
•Current washing and water-only field decontamination techniques do not effectively remove SVOCs from firefighters' uniforms.•Contamination of washing machines and cross-contamination of laundry can occur when washing firefighting uniforms.•Chemical diffusion from firefighting uniforms may contribute to the air and dust concentration of SVOCs in fire stations.
•Socks, briefs and crop tops worn during firefighting activities can become contaminated by polycyclic aromatic hydrocarbons.•Laundering resulted in a slight reduction of the concentration of PAHs in ...socks and briefs, while increasing in crop tops.•Domestic laundering is insufficient to remove the contaminants on such items.•The change in these concentrations of PAHs did not appear to differ between laundry detergents used.•It is recommended firefighters remove these items as soon as possible and launder them separately from domestic laundry.
Firefighters are exposed to a wide range of toxic chemicals due to combustion, with numerous biomonitoring studies completed that have assessed exposure. Many of these studies focus on individual ...classes of chemicals, with a few considering a broad range of systemic exposures. As yet, no review process has been undertaken to comprehensively examine these studies. The aims of this review are to: (1) ascertain whether biomonitoring studies pertaining to firefighters demonstrate occupational exposure to volatile organic compounds, semivolatile organic compounds, and metals; (2) determine and present results of biomonitoring studies; (3) provide any recommendations presented from the literature that may support exposure mitigation; and (4) suggest future study parameters that may assist in providing a greater understanding surrounding the occupational exposure of firefighters. A systematic review was undertaken with regards to firefighters and biomonitoring studies utilising the matrices of blood, urine, semen and breast milk. This yielded 5690 results. Following duplicate removal, inclusion and exclusion criteria screening and full text screening, 34 studies remained for review. Results of over 80% of studies analysed determined firefighters to experience occupational exposure. Results also show firefighters to be exposed to a wide range of toxic chemicals due to fire smoke; potentially exceeding the range of exposure of other occupations. As firefighters may face increased risk of health effects due to the additive, synergistic, and/or antagonistic effects of chemical exposure, all care must be taken to reduce exposure. This may be achieved by considering tactical decisions, increased personal hygiene, and thorough decontamination procedures. Future biomonitoring studies recognising and assessing the range of chemical exposure firefighters face would be beneficial.
•Results of over 80% of studies analysed by systematic review determine firefighters to experience occupational exposure.•The wide range of toxic chemicals due to fire smoke may lead to firefighters exceeding the range of exposure of other occupations.•Firefighters may face increased risk of health effects due to the additive, synergistic, and/ or antagonistic effects of chemical exposure.•All care must be taken to reduce exposure by considering tactical decisions, increased personal hygiene, and thorough decontamination procedures.•Future biomonitoring studies recognising and assessing the range of chemical exposure firefighters face would be beneficial, as would those following a cohort over time.
This systematic review examines biomonitoring studies that have assessed firefighter occupational exposure to chemicals due to combustion.
This study assessed the composition of single-use face mask materials, quantified the concentration of phthalate esters in masks and evaluated associated inhalation exposure risk. All the mask ...samples, including 12 surgical and four N95/P1/P2 masks, were identified to be made of polypropylene, with polyethylene terephthalate present in the N95/P1/P2 masks. Di-methyl phthalate, di-n-butyl phthalate, di-ethyl phthalate, di-isobutyl phthalate and di(2-ethylhexyl) phthalate were frequently detected and their concentration summed up 55 ± 35 ~ 1700 ± 140 ng per surgical mask and 2300 ± 150 ~ 5200 ± 800 ng per N95/P1/P2 mask. Our simulation experiment suggested a mean loss of 13 – 71% of phthalate mass depending on compounds, during 5-hour wearing of these masks. This resulted in an estimated daily intake of individual compounds no higher than 20 ng/kg/day for adults and 120 ng/kg/day for toddlers, which were at least 80 times lower compared to relevant tolerable daily intake values. Two interventional trials were conducted where a volunteer wore a mask for four hours and urine samples were collected before and after the mask wearing. No obvious increase was observed for the urinary concentration of any phthalate metabolite, indicating minimal contribution to overall exposure to phthalate esters.
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•Single-use face masks generally composed of polypropylene.•Phthalate concentrations in face masks were quantified.•DnBP and DEHP were the greatest contributors to the summed phthalates.•Exposure to phthalates via mask wearing was quantified but risk is low per each use.
Firefighters are exposed to a wide variety of chemicals including polycyclic aromatic hydrocarbons (PAHs) while attending fire scenes. The objective of this study was to understand the exposure of ...firefighters to PAHs when attending simulated compartment fires that consisted of either a diesel pan or particleboard fire. Firefighters remained in the compartment fires for 15 min while using standard gear including self contained breathing apparatus (SCBA). Firefighters were able to remove firefighting clothing and shower within 10 min of leaving the burn. Air samples were collected from inside the compartment during the fire. Twenty-six (26) firefighters participated in the study providing urine and skin wipe samples collected from the wrist and neck before and after either one of the burn types. The concentrations of PAHs were measured in skin wipes and air samples, while concentrations of monohydroxy metabolites of PAHs (OH-PAHs) were measured in urine. The concentrations of all PAHs were significantly higher (p < 0.05) in the smoke layer of particleboard fires than in diesel pan fires. Correspondingly, the level of PAHs deposited on the wrists and necks of participants attending the particleboard fires was higher than those attending diesel pan fires. Urine samples from participants who attended diesel pan fires showed no significant difference (p > 0.05) in the concentration of all OH-PAHs between pre-burn and post-burn. Samples from participants who attended particleboard fires, showed no significant difference (p > 0.05) between 1-hydroxypyrene (1-OH-PYR) concentrations in urine pre- and post-burn. However, median concentrations of hydroxynaphthalenes (OH-NAPs), hydroxyfluorenes (OH-FLUs) and hydroxyphenanthrenes (OH-PHEs) increased significantly from 5.2, 0.44 and 0.88 μg g−1 creatinine pre-burn to 12, 1.4 and 1.2 μg g−1 creatinine post-burn, respectively. This suggests that in compartment burns with high concentrations of PAHs in the smoke layer, such as those created by the particleboard fires, exposure to PAHs can be observed though urinary OH-PAH metabolites. Overall, concentrations of urinary OH-PAHs were relatively low considering the potential exposure in these burns. This suggests protective equipment in combination with rapid removal of firefighting ensembles and showering are relatively effective in controlling exposure.
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