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The share of biofuels in the transportation sector is increasing. Previous studies revealed that the use of biofuels decreases the size of particles (which is linked to an increase in particulate toxicity). Current emission regulations do not consider small particles (sub-23 nm); however, there is a focus in future emissions regulations on small particles. These and the fact that within cold-start emissions are higher than during the warmed-up operation highlight the importance of a research that studies particulate matter emissions during cold-start. This research investigates the influence of biofuel on PN and PM concentration, size distribution, median diameter and cumulative share at different size ranges (including sub-23 nm and nucleation mode) during cold-start and warm-up operations using diesel and 10, 15 and 20% mixture (coconut biofuel blended with diesel). During cold-start, between 19 and 29% of total PN and less than 0.8% of total PM were related to the nucleation mode (sub-50 nm). Out of that, the share of sub-23 nm was up to 9% for PN while less than 0.02% for PM. By using biofuel, PN increased between 27 and 57% at cold-start; while, the increase was between 4 and 19% during hot-operation. The median diameter also decreased at cold-start and the nucleation mode particles (including sub-23 nm particles) significantly increased. This is an important observation because using biofuel can have a more adverse impact within cold-start period which is inevitable in most vehicles’ daily driving schedules.

Lay summary Firefighters are occupationally exposed to heat intensities and chemical concentrations that may affect fertility. Twenty firefighters participated in an exploratory study assessing fertility of firefighters via an online survey and semen analysis. Data analysis included consideration of demographic characteristics, reproductive history and occupational exposures. Overall, firefighter semen parameters were below World Health Organisation reference values designating fertility in men. Firefighters younger than 45 years had a higher incidence of abnormal semen parameters (42%) than those aged 45 years or greater (9%). Increased rank and higher levels of occupational and/or personal hygiene were associated with improved semen quality. Increased frequency of fire exposure was associated with a reduction in normal forms, volume, sperm concentration and total sperm count. Sperm clumping was greater than 10% in 26% of samples, suggesting reduced semen quality. This exploratory study provides novel data that support the hypothesis of an association between semen quality and firefighter’s occupational exposure to toxic environments.

Diesel emissions contain high levels of particulate matter (PM) which can have a severe effect on the airways. Diesel PM can be effectively reduced with the substitution of diesel fuel with a biofuel such as vegetable oil. Unfortunately, very little is known about the cellular effects of these alternative diesel emissions on the airways. The aim of this study was to test whether coconut oil substitution in diesel fuel reduces the adverse effect of diesel emission exposure on human bronchial epithelial cells. Human bronchial epithelial cells were cultured at air-liquid interface for 7 days and exposed to diesel engine emissions from conventional diesel fuel or diesel fuel blended with raw coconut oil at low (10%), moderate (15%) and high (20%) proportions. Cell viability, inflammation, antioxidant production and xenobiotic metabolism were measured. Compared to conventional diesel, low fractional coconut oil substitution (10% and 15%) reduced inflammation and increased antioxidant expression, whereas higher fractional coconut oil (20%) reduced cell viability and increased inflammation. Therefore, cellular responses after exposure to alternative diesel emission are dependent on fuel composition.

Endogenous chemicals specific to human metabolism have been suggested to be good candidates for markers of population size in wastewater-based epidemiology (WBE). So far, creatinine is the only endogenous chemical to be assessed against the criteria of in-sewer stability. This study thus aimed to evaluate the fate of three other endogenous compounds, 5-hydroxy indole acetic acid (5-HIAA), cortisol and androstenedione, under different sewer conditions using laboratory-scale sewer reactors. The results showed that while all compounds were stable in wastewater only (i.e. without biofilm), cortisol and androstenedione degraded quickly in sewers with the presence of sewer biofilms. The degradation followed first-order kinetics similar to that of creatinine. In contrast, 5-HIAA was relatively stable in sewer reactors. This study also recognised the impact of wastewater pH on the detectability of 5-HIAA using a LC-MS/MS direct injection method. In samples acidified to pH 2, the method did not allow routine detection/quantification of 5-HIAA whereas in non-acidified samples the method was sufficiently sensitive for routine quantification of 5-HIAA. The stability of 5-HIAA in sewers and the possibility to measure it using a simple and rapid analytical method corroborate that 5-HIAA may be a suitable biomarker for estimation of population size in WBE.

Human biomonitoring of persistent organic pollutants (POPs) is typically based on serum analysis and for comparison and modelling purposes, data are often normalised to the lipid content of the serum. Such approach assumes a steady state of the compound between the serum lipids and for example lipid-rich adipose tissue. Few published data are available to assess the validity of this assumption. The aim of this study was to measure concentrations of POPs in both serum and adipose tissue samples from 32 volunteers and compare the lipid-normalised concentrations between serum and adipose tissue. For p,p'-DDE, PCB-138, PCB-153 and PCB-180, lipid-normalised adipose tissue concentrations were positively correlated to the respective serum concentrations but generally were more highly concentrated in adipose tissue. These results suggest that the investigated legacy POPs that were consistently found in paired samples may often not be in a steady state between the lipid compartments of the human body. Consequently, the analysis of serum lipids as a surrogate for adipose tissue exposure may more often than not underestimate total body burden of POPs. Further research is warranted to confirm the findings of this study.

Firefighters’ uniforms become contaminated with a wide range of chemicals, including polycyclic aromatic hydrocarbons (PAHs), organophosphate flame retardants (OPFRs), and polybrominated diphenyl ethers (PBDEs). Laundering practices do not completely remove PAHs, OPFRs, and PBDEs from firefighting uniforms. This residual contamination of firefighting ensembles may be an ongoing source of exposure to firefighters. Firefighters are known to occasionally store firefighting ensembles in private vehicles. This study aimed to assess whether a firefighting uniform in a vehicle could act as a source for PAHs, OPFRs, and PBDEs to vehicle users. The shell layers of four laundered firefighting uniforms were sampled non-destructively. Three of these uniforms were heated in a laboratory oven (40, 60, and 80 °C) while the fourth was placed in a private vehicle on a summer day and off-gassing samples were collected from the uniforms. The off-gassing results for PAHs and OPFRs were relatively consistent between laboratory oven and the in-vehicle sample with ∑13 PAHs in off-gas ranging from 7800–23,000 ng uniform−1 day−1, while the ∑6 OPFRs off-gassed was an order of magnitude lower at 620–1600 ng uniform−1 day−1. The off-gassing results for PBDEs were much lower and less consistent between the experiments, which may reflect differences in uniform history. Currently, there is limited understanding of how PAHs, OPFRs, and PBDEs off-gassed from firefighting uniforms influence firefighter exposure to these chemicals. These findings suggest that firefighting ensembles off-gassing in private vehicles could be a relevant source of PAHs, OPFRs, and PBDEs that contributes to firefighters’ exposure and that this warrants further investigation.

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.

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 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.

This study investigates the effect of engine temperature during cold start and hot start engine operation on particulate matter emissions and engine performance parameters. In addition to a fundamental study on cold start operation and the effect of lubricating oil during combustion, this research introduces important knowledge about regulated particulate number emissions and particulate size distribution during cold start, which is an emerging area in the literature. A further aspect of this work is to introduce waste lubricating oil as a fuel. By using diesel and two blends of diesel with 1 and 5% waste lubricating oil in a 6-cylinder turbocharged engine on a cold start custom test, this investigation studied particle number (PN), friction losses and combustion instability with diesel and waste lubricating oil fuel blends. In order to understand and explain the results the following were also studied: particle size distribution and median diameter, engine oil, coolant and exhaust gas temperatures, start of injection, friction mean effective pressure (FMEP), mechanical efficiency, coefficient of variation (CoV) of engine speed, CoV of indicated mean effective pressure (IMEP) and maximum rate of pressure rise were also studied. The results showed that during cold start the increase in engine temperature was associated with an increase in PN and size of particles, and a decrease in FMEP and maximum rate of pressure rise. Compared to a warmed up engine, during cold start, PN, start of injection and mechanical efficiency were lower; while FMEP, CoV of IMEP and maximum rate of pressure rise were higher. Adding 5% waste lubricating oil to the fuel was associated with a decrease in PN (during cold start), decreased particle size, maximum rate of pressure rise and CoV of IMEP and was associated with an increase in PN and nucleation mode particles (during hot start) and FMEP.

[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA; International audience; Glyphosate (PMG) is one of the most widely used herbicides with a reported 8.6 million tons applied globally in 2016. Due to widespread use and limited understanding of long-term environmental impacts, it is expected that future monitoring requirements for PMG and its primary metabolite aminomethyl phosphonic acid (AMPA) in aquatic environments will increase, along with the need for low cost monitoring and risk assessment strategies. The aim of this study was to investigate a microporous polyethylene tube (MPT; 2-mm thickness, 17.6 cm2 surface area, 35% porosity, 2.5 μm pore size) as a diffusive layer for the passive sampling of PMG and AMPA. Levels of PMG and AMPA sorbed to MPT were low ($K_{mw}$ close to 1 mL $g^{−1}$), validating MPT as a diffusive layer. Uptake experiments were conducted first under controlled laboratory conditions (pH = 6.8, 6 days), followed by an in situ freshwater lake system deployment (pH = 7.3, 11 days). PMG and AMPA accumulated linearly (slope relative standard deviation < 6%) under laboratory conditions with sampling rates ($R_s$) of 18 and 25 mL d$^{−1}$, respectively. PMG in situ $R_s$ was 28 mL $d^{-1}$, and was not different from the one found in the laboratory. AMPA was below the limit of quantification (LOQ, 1 ng mL$^{−1}$) in grab water samples, but was detected (>LOQ) in all passive samplers. Results illustrate the gain in sensitivity provided by the passive sampling technique, and the applicability of the device developed for the passive sampling of PMG and AMPA.

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 ∑13PAH 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.

Our previous biomonitoring study of hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) in a population in Australia found high levels of 1-naphthol, a metabolite of both naphthalene and carbaryl, in some adult samples. Here, we conducted a follow-up study to collect and analyse pooled urine samples, stratified by age and sex, from 2014 to 2017 using a GC-MS method. Geometric mean concentrations of 1-hydroxypyrene, the most common biomarker of PAH exposure, were 100 and 120 ng/L urine in 2014–2015 and 2016–2017, respectively. The concentrations of most OH-PAHs in this study except 1-naphthol are in line with those reported by biomonitoring programs in the US and Canada. In general, concentrations of OH-PAHs are lower in samples from small children (0–4 years) and school-aged children (5–14 years) compared with samples from the older age groups, except for some cases in the recent monitoring period. The concentrations of 1-naphthol in some adult samples of both sexes are very high, which is consistent with our previous findings. Such high concentrations of 1-naphthol together with the high 1-naphthol/2-naphthol ratio suggest potential exposure to the insecticide carbaryl in this population but other exposure sources and different rates of naphthalene metabolism should also be investigated.

NOx emissions from diesel engines are a concern from both environmental and health perspectives. Recently this attention has targeted cold-start emissions highlighting that emission after-treatment systems are not effective in this period. Using a 6-cylinder, turbocharged, common-rail diesel engine, the current research investigates NOx emissions during cold-start using different engine performance parameters. In addition, it studies the influence of waste lubricating oil on NOx emissions introducing it as a fuel additive (1 and 5% by volume). To interpret the NOx formation, this study evaluates different parameters: exhaust gas temperature, engine oil temperature, engine coolant temperature, start of injection/combustion, in-cylinder pressure, heat release rate, maximum in-cylinder pressure and maximum rate of pressure rise. This study clarified how cold-start NOx increases as the engine is warming up while in general cold-start NOx is higher than hot-start. Results showed that in comparison with warmed up condition, during cold-start NOx, maximum in-cylinder pressure and maximum rate of pressure rise were higher; while start of injection, start of combustion and ignition delay were lower. During cold-start increased engine temperature was associated with decreasing maximum rate of pressure rise and peak apparent heat release rate. During cold-start NOx increased with temperature and it dropped sharply due to the delayed start of injection. This study also showed that using waste lubricating oil decreased NOx and maximum rate of pressure rise; and increased maximum in-cylinder pressure. NOx had a direct correlation with the maximum rate of pressure rise; and an inverse correlation with the maximum in-cylinder pressure.

Chlorinated paraffins (CPs) are high production volume chemicals of which some show resistance to environmental degradation, long-rang transport, bioaccumulation and toxicity potential. Information regarding their presence in humans is limited, including their human bioaccumulation potential. The present study aimed to evaluate CP levels in human serum from Australia in order to better understand their exposure and current pollution status as well as trends associated with age and time between 2004 and 2015. For this, we selected a male sub-group of the Australian population under 60 years old (n = 16 pools, total 1600 serum samples). While long-chain CP (C18-20) and most short-chain CP (C10-13, SCCPs) levels were below method detection limits (MDL), medium-chain CPs (C14-17, MCCPs) were found in most serum samples (detection frequency 94%) as well as CPs with a carbon chain length of nine (detection frequency 76%). The levels of ΣSCCPs and ΣMCCPs ranged from

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., Environment International, 122, ISSN:0160-4120, ISSN:1873-6750

Concentrations of nine organophosphate flame retardants (OPFRs) and eight polybrominated diphenyl ethers (PBDEs) were measured in samples of indoor dust (n = 85) and air (n = 45) from Australian houses, offices, hotels, and transportation (buses, trains, and aircraft). All target compounds were detected in indoor dust and air samples. Median ∑9OPFRs concentrations were 40 μg/g in dust and 44 ng/m3 in indoor air, while median ∑8PBDEs concentrations were 2.1 μg/g and 0.049 ng/m3. Concentrations of FRs were higher in rooms that contained carpet, air conditioners, and various electronic items. Estimated daily intakes in adults are 14000 pg/kg body weight/day and 330 pg/kg body weight/day for ∑9OPFRs and ∑8PBDEs, respectively. Our results suggest that for the volatile FRs such as tris(2-chloroethyl) phosphate (TCEP) and TCIPP, inhalation is expected to be the more important intake pathway compared to dust ingestion and dermal contact.

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.

© 2019 Firefighting is an occupation with exposure to a wide range of chemicals by means of inhalation, ingestion or dermal contact. Although advancements in personal protective clothing and equipment have reduced the risks for acute exposure during fire suppression operations, chronic exposure may still be present at elevated levels in fire stations. The aim of this study was to assess chemicals in air and on surfaces in fire stations, compare this with other indoor environments, and use this data to estimate firefighter exposure within the fire station. Fifteen Australian fire stations were selected for chemical exposure assessment by means of 135 active air monitors, 60 passive air monitors, and 918 wipe samples. These samples were collected from the interior and exterior of fire stations, from personal protective clothing and equipment, and from within the cabins of vehicles. Chemicals analysed included polycyclic aromatic hydrocarbons, volatile organic compounds, metals, and diesel particulate matter. Specific chemicals were detected from within each class of chemicals, with metals being most frequently detected. Statistical analysis by means of Pearson's Correlations and threshold tests were used to consider the source of exposure, and a collective addition risk quotient calculation was used to determine firefighter exposure. The presence of metals in fire stations was compared with findings from global indoor dust measurements. Concentrations across firefighter ensemble, inside vehicle cabins, and within fire stations for chromium (39.5–493 μg/m2), lead (46.7–619 μg/m2), copper (594–3440 μg/m2), zinc (11100-20900 μg/m2), nickel (28.6–2469 μg/m2) and manganese (73.0–997 μg/m2) were in most instances orders of magnitude higher when compared with concentrations measured in homes and offices. Our study suggests that the elevated concentrations are associated with the transfer of chemicals from fire suppression operations. Due to this elevated concentration of chemicals, firefighters may face increased exposure, and in turn increased risk of adverse health effects. Data suggest that exposure may be mitigated by means of increased laundering frequency and increased decontamination at the scene of the fire. Capsule: This study examines the exposures firefighters face to metals and other chemicals while at the fire station.

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

Polybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardants (BFRs) once extensively used in the plastics of a wide range of consumer products. The listing of certain congeners that are constituents of commercial PBDE mixtures (including c-octaBDE) in the Stockholm Convention and tightening regulation of many other BFRs in recent years have created the need for a rapid and effective method of identifying BFR-containing plastics. A three-tiered testing strategy comparing results from non-destructive testing (X-ray fluorescence (XRF)) (n = 1714), a surface wipe test (n = 137) and destructive chemical analysis (n = 48) was undertaken to systematically identify BFRs in a wide range of consumer products. XRF rapidly identified bromine in 92% of products later confirmed to contain BFRs. Surface wipes of products identified tetrabromobisphenol A (TBBPA), c-octaBDE congeners and BDE-209 with relatively high accuracy (>. 75%) when confirmed by destructive chemical analysis. A relationship between the amounts of BFRs detected in surface wipes and subsequent destructive testing shows promise in predicting not only the types of BFRs present but also estimating the concentrations present. Information about the types of products that may contain persistent BFRs will assist regulators in implementing policies to further reduce the occurrence of these chemicals in consumer products. © 2014 Elsevier B.V.

Wastewater-based epidemiology (WBE) is considered to be a useful tool for monitoring chemical consumption in the population. However, the lack of information on potential transformation of biomarkers in the sewer system can compromise the accuracy of the consumption estimation. The present study contributes to addressing this issue by investigating the in-sewer stability of biomarkers from a number of commonly used drugs using laboratory sewer reactors that canmimic different sewer conditions. A stable and an unstable chemical (carbamazepine and caffeine) were also used as benchmarking chemicals to reflect the chemical degradation potential in different sewer conditions. The results suggested that ketamine and norketamine were unstable in gravity and rising main sewers, ketamine was unstable in bulk liquid while norketamine was stable under the same condition. Similarly, mephedrone and methylone were unstable in sewer conditions with considerable deviation. Significant loss of buprenorphine, methadone, oxycodone and codeine was observed in the rising main sewer. Morphine and codeine glucuronide were found to be deconjugated from their glucuronides quickly in the presence of biofilms. This study indicates that it is important to evaluate the stability of biomarkers in the sewer system before using them in WBE for estimating consumption/exposure to reduce uncertainties. (C) 2017 Elsevier B.V. All rights reserved.

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.

The levels of perfluroalkyl substances (PFASs), polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCDDs) were studied in Australian landfill leachate and biosolids. Leachate was collected from 13 landfill sites and biosolids were collected from 16 wastewater treatment plants (WWTPs), across Australia. Perfluorohexanoate (PFHxA) (12-5700ng/L) was the most abundant investigated persistent, bioaccumulative and toxic (PBT) chemical in leachate. With one exception, mean concentrations of PFASs were higher in leachate of operating landfills compared to closed landfills. Polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane isomers (HBCDDs) were detected typically at operating landfills in comparatively lower concentrations than the PFASs. Decabromodiphenyl ether (BDE-209) (