Organophosphate flame retardants (PFRs) have been proposed as alternatives for the phased out PBDE formulations. However, there exists no information on indoor dust contamination with PFRs in Africa. ...In this study, we report--for the first time--on levels and profiles of PFRs in dust samples from Egyptian houses (n = 20), offices (n = 20), cars (n = 20), and public microenvironments (PMEs; n = 11). Results revealed that PFR levels in Egyptian indoor dust are among the lowest reported worldwide. This may be attributed to less strict fire-safety standards and lack of regulatory actions against PBDEs. Triphenylphosphate was the only PFR detected in all samples with highest average concentration (386 ng g(-1)). While tris-2-chloroethyl phosphate, tris(1-chloro-2-propyl)phosphate and tris-1,3-dichloropropylphosphate showed higher detection frequency (DF = 69%, 57%, and 56%; average = 233, 229, and 144 ng g(-1), respectively), tri(2-butoxyexthyl)phosphate (37%; 294 ng g(-1)) displayed the second highest average concentration. Statistical analysis revealed significantly (P < 0.05) higher concentrations of ΣPFRs in cars (average = 1011 ng g(-1)) and PMEs (2167 ng g(-1)) than in houses (310 ng g(-1)) and offices (450 ng g(-1)). Estimated exposures of adults and toddlers to PFRs via dust ingestion were much lower than the reported reference doses, indicating no immediate health risk to the Egyptian population.
Organophosphate esters (OPEs) are ubiquitous in the environment and may pose potential health risks to humans. Drinking water is suspected as one possible exposure pathway of OPEs to humans. In this ...study, we investigated the residues of 9 OPEs in five types of drinking water in Eastern China. The median concentrations of Σ9OPEs were determined to be 3.99, 4.50, 27.6, 59.2 and 192ng/L in the bottled, well, barreled, direct drinking and tap waters, respectively. Triethyl phosphate (TEP) was the most abundant OPE in the tap water and filtered drinking water with median concentrations of 50.2 and 30.2ng/L, respectively. The mixture of tri(chloropropyl) phosphate (TCPP) and tri(chloroisopropyl) phosphate (TCIPP), named here as TCPP, dominated in the barreled and well water with median concentrations of 8.04 and 2.49ng/L, respectively. The calculated average daily doses of OPEs ranged from 0.14 to 7.07ng/kgbw/day for people consuming the five different types of drinking water. Among the drinking water, the tap water exhibited the highest exposure doses of OPEs. The calculated non-cancer hazard quotients (10−4–10−7) from OPEs were much lower than the theoretical threshold of risk. The carcinogenic risks posed by TCEP were very low (<10−7) for all types of drinking water. The results revealed that there was currently low risk to human health from exposure to OPEs through drinking water in Eastern China.
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•Residues of OPEs in drinking water were investigated in Eastern China.•The concentrations of OPEs in tap water were higher than other drinking waters.•Uptake of OPEs via drinking water was similar to airborne exposure for adults.•Non-cancer and carcinogenic risks of OPEs for people via drinking water were low.
The bioavailability and biomagnification of organophosphate esters (OPEs) were investigated in a food web in the Zhushan Bay of Taihu Lake, China. The organisms included mainly three biological ...groups: plankton, invertebrates, and fish, which displayed distinctly different compositional profiles of OPEs. In general, the log BAFs (bioaccumulation factor) of OPEs displayed a significant correlation with their log Kow (octanol-water partitioning coefficient), suggesting that the bioaccumulation was mainly controlled by the hydrophobicity. The log BAFs of the more hydrophobic OPEs in benthic invertebrates were higher than in fish, suggesting that ingesting sediment constituted additional exposure route for benthic invertebrates. The log BSAFs (biota-sediment accumulation factor) in the benthic invertebrates increased with log Kow in the range of 1.44–5.73 and decreased afterwards. The depressed bioavailability of the highly hydrophobic OPEs was attributed to their strong adsorption to the sediment. The biomagnification potency of OPEs was affected by hydrophobicity of the compounds and biotransformation properties in the organisms at different trophic levels. 2-Ethylhexyl diphenyl phosphate biomagnified in the fish food web of Taihu Lake with a TMF (trophic magnification factor) of 3.61, which was due to the combined results of its relatively high hydrophobicity (log Kow of 5.73) and decreased metabolism potential in the high-trophic-level fish. The constant metabolism diminished the biomagnification potency of hydrophobic compounds triphenyl phosphate and tricresyl phosphate in this food web.
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•Plankton, invertebrates, and fish displayed distinctly different OPE profiles.•Log BAFs of hydrophobic OPEs in benthic invertebrates were higher than in fish.•Parabolic relationship was obtained between log BSAF and log Kow for OPEs.•The OPE biomagnification was also affected by metabolisms in different organisms.•EHDPP biomagnified in the fish food web of Taihu Lake with a TMF of 3.61.
► Bisphenol-A, triclosan and nonyl-phenol were at low ng/g levels in human tissues. ► Highest concentrations of bisphenol-A were found in adipose tissue, followed by liver. ► Highest concentrations ...of triclosan were found in liver, followed by adipose tissue. ► Nonyl-phenol was not detected in the majority of the samples. ► These phenolic compounds seem to have a low bioaccumulation potential.
In this study, an analytical method was optimized for the determination of bisphenol-A (BPA), triclosan (TCS) and 4-n-nonylphenol (4n-NP), environmental contaminants with potential endocrine disruptive activities, in human tissues. The method consisted of a liquid extraction step, derivatization with pentafluorobenzoylchloride followed by a clean-up on acidified silica and detection with gas chromatography coupled with mass spectrometry (GC-ECNI/MS). Recoveries ranged between 92% and 102% with a precision below 5%. Limits of quantification ranged between 0.3–0.4ngg−1, 0.045–0.06ngg−1 and 0.003–0.004ngg−1 for BPA, TCS and 4n-NP in different tissues, respectively. The method was applied for the determination of BPA, TCS and 4n-NP in paired adipose tissue, liver and brain samples from 11 individuals. BPA could be detected in almost all tissues, with the highest concentrations found in adipose tissue (mean 3.78ngg−1), followed by liver (1.48ngg−1) and brain (0.91ngg−1). TCS showed the highest concentrations in liver (3.14ngg−1), followed by adipose tissue (0.61ngg−1), while it could be detected in only one brain sample. Levels of 4n-NP were much lower, mostly undetected, and therefore 4n-NP is considered of minor importance for human exposure. Despite the measurable concentrations in adipose tissue, these compounds seem to have a low bioaccumulation potential. The reported concentrations of free BPA in the various tissues are slight disagreement with pharmacokinetic models in humans and rats and therefore the possibility of external contamination with BPA during sample collection/storage cannot be ruled out.
As many people spend a large part of their life indoors, the quality of the indoor environment is important. Data on contaminants such as flame retardants, pesticides and plasticizers are available ...for indoor air and dust but are scarce for consumer products such as computers, televisions, furniture, carpets, etc.
This review presents information on semi-volatile organic compounds (SVOCs) in consumer products in an attempt to link the information available for chemicals in indoor air and dust with their indoor sources. A number of 256 papers were selected and divided among SVOCs found in consumer products (n = 57), indoor dust (n = 104) and air (n = 95). Concentrations of SVOCs in consumer products, indoor dust and air are reported (e.g. PFASs max: 13.9 μg/g in textiles, 5.8 μg/kg in building materials, 121 ng/g in house dust and 6.4 ng/m3 in indoor air). Most of the studies show common aims, such as human exposure and risk assessment. The main micro-environments investigated (houses, offices and schools) reflect the relevance of indoor air quality. Most of the studies show a lack of data on concentrations of chemicals in consumer goods and often only the presence of chemicals is reported. At the moment this is the largest obstacle linking chemicals in products to chemicals detected in indoor air and dust.
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•Information on semi-volatile organic compounds (SVOCs) in consumer products, indoor air and dust was reviewed.•Limited data on concentrations of SVOCs in consumer goods is available, mainly their presence is reported.•The largest obstacle linking SVOCs in products to indoor air/dust ones is the lack on SVOC concentrations in consumer goods.
The occurrence of eight phosphorus flame retardants (PFRs) was investigated in 53 composite food samples from 12 food categories, collected in 2015 for a Swedish food market basket study. ...2-ethylhexyl diphenyl phosphate (EHDPHP), detected in most food categories, had the highest median concentrations (9 ng/g ww, pastries). It was followed by triphenyl phosphate (TPHP) (2.6 ng/g ww, fats/oils), tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) (1.0 ng/g ww, fats/oils), tris(2-chloroethyl) phosphate (TCEP) (1.0 ng/g ww, fats/oils), and tris(1-chloro-2-propyl) phosphate (TCIPP) (0.80 ng/g ww, pastries). Tris(2-ethylhexyl) phosphate (TEHP), tri-n-butyl phosphate (TNBP), and tris(2-butoxyethyl) phosphate (TBOEP) were not detected in the analyzed food samples. The major contributor to the total dietary intake was EHDPHP (57%), and the food categories which contributed the most to the total intake of PFRs were processed food, such as cereals (26%), pastries (10%), sugar/sweets (11%), and beverages (17%). The daily per capita intake of PFRs (TCEP, TPHP, EHDPHP, TDCIPP, TCIPP) from food ranged from 406 to 3266 ng/day (or 6–49 ng/kg bw/day), lower than the health-based reference doses. This is the first study reporting PFR intakes from other food categories than fish (here accounting for 3%). Our results suggest that the estimated human dietary exposure to PFRs may be equally important to the ingestion of dust.
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•The occurrence of eight PFRs was investigated in 53 samples from 12 food categories.•EHDPHP was detected in most food samples and had the highest median concentrations.•Cereals, pastries, sweets, and beverages contributed the most to the PFR intake.•The daily per capita intake of PFRs from food ranged from 6 to 49 ng/kg bw/day.•The dietary exposure to PFRs may be equally important to dust ingestion.
Due to increasing amounts of hazardous chemicals released into the environment, there is a high demand for developing easy and non-destructive biomonitoring tools. In a recent paper published in ...Trends in Analytical Chemistry, Rutkowska et al. (2018) concluded that feathers are a good matrix for biomonitoring of environmental pollutants in birds. In this commentary, we discuss the general conclusion of this paper. We provide several examples for which this statement is not correct, and we emphasize that only for legacy persistent organic pollutants (POPs) and mercury there is currently enough scientific evidence to use feathers as a reliable biomonitor, given that appropriate sampling designs and QA/QC protocols are taken into account. Furthermore, we discuss different pretreatment (e.g. feather washing) and analytical protocols along with specific QA/QC to be considered. In summary, this commentary provides an overview of the prospects and pitfalls when using feathers as a biomonitor for environmental pollutants.
•The suitability of feathers as a biomonitor for various contaminants is discussed.•Pitfalls regarding collection, storage, preparation and analysis are presented.•Recommendations regarding QA/QC for different contaminants are given.•Feathers can be useful as a biomonitor for POPs, Hg and potentially other metals.•Other contaminants need further study before feathers can be used for biomonitoring.
The present study was carried out in Nepal, a landlocked country located between world's two most populous countries i.e. India and China. In this study, the occurrence, profiles, spatial ...distributions and fate of eight organophosphate ester flame retardants (OPFRs) were investigated in indoor air and house dust. Overall, the concentrations of ∑OPFR were in the range of 153–12100 ng/g (median732 ng/g) and 0.32–64 ng/m3 (median 5.2 ng/m3) in house dust and indoor air, respectively. The sources of high OPFR in the indoor environment could be from locally used wide variety of consumer products and building materials in Nepalese houses. Significantly, high concentration of tri-cresyl phosphate (TMPP) was found both in air and dust, while tri (2-ethylhexyl) phosphate (TEHP) had the highest concentration in air samples. It might be due to fact that the high concentrations of TMPP are related to intense traffic and/or nearby airports. On the other hand, significantly high concentration of TEHP could be due to anthropogenic activities. Only TEHP showed positive correlation between indoor air and house dust (Rho = 0.517, p < 0.01), while rest of compounds were either less correlated or not correlated at all. The estimated human exposure to ∑OPFR via different pathway of intake suggested dermal absorption via indoor dust as major pathway of human exposure to both children and adult population. However, other pathways of OPFR intake such as dietary or dermal absorption via soil may still be significant in case of Nepal.
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•Concentration of OPFRs were highly detected in house dust than indoor air.•Source of OPFR in this study was from locally used consumer products and building materials.•Elevated level of TMPPs were related to intense traffic emission and/or nearby airport.•Dermal absorption via indoor dust was major pathway of human exposure in Nepal.
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•Most OPEs tend to bind with plasma proteins, such as human serum albumin.•Metabolism and binding with plasma proteins affect the clearance rates of OPEs.•Extrapolation from the in ...vitro microsomal intrinsic clearance method is feasible.•Half-lives of Cl-OPEs are longer than those of the aryl- and alkyl-OPEs.
The renal and hepatic clearance rates of organophosphate esters (OPEs) in humans were estimated. Six OPEs and their corresponding diester metabolites (mOPEs) were quantified respectively in 30 paired human plasma and urine samples collected in Hengshui, Hebei province, China. The renal clearance rate (CLrenal) of triphenyl phosphate (TPHP), tris(chloroethyl) phosphate (TCEP) and tris(1,3-dichloro-isopropyl) phosphate (TDCIPP) was estimated to be 68.9, 50.9 and 33.3 mL/kg/day, respectively, while it was not calculated for other three OPEs due to the low detection frequencies in human samples. To estimate the clearance rates of the target OPEs, hepatic clearance rates (CLh) of OPEs were extrapolated from their in vitro intrinsic clearance data in human liver microsomes (CLHLM). The calculated CLh values of TCEP and TDCIPP were comparable to their CLrenal, indicating that the in vitro extrapolation method was suitable for estimating the clearance rates of OPEs. The higher binding affinity of TDCIPP with plasma proteins could reduce its renal clearance. The estimated half-lives of Cl-OPEs in human were longer than those of the aryl- and alkyl-OPEs. This study provided a feasible in vitro method to predict the clearance and half-lives of OPEs in human, which is significant for their accurate health risk assessment.
•First qualitative metabolism study on PFRs using human liver microsomes.•Rates of substrate depletion were lowest for tris(2-chloroethyl) phosphate.•Tris(dichloropropyl)phosphate metabolism was ...similar to in vivo rat studies.•Triphenyl phosphate was mostly transformed by hydroxylation.•Tris(chloropropyl) phosphate was mostly metabolized by oxidative dehalogenation.
Phosphate flame retardants and plasticizers (PFRs) are additives used in a wide range of polymers. Important representatives, such as tris(2-butoxyethyl) phosphate (TBOEP), triphenyl phosphate (TPHP), tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCIPP), tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), have been found in the indoor environment at high levels. Biotransformation of these PFRs needs to be investigated because it can be a major determinant of their bioavailability and toxicity in humans. TBOEP, TPHP, TCEP, TCIPP and TDCIPP were incubated with human liver S9 fraction and microsomes. Supernatants were analyzed using a liquid chromatography coupled to a quadrupole-time-of-flight mass spectrometer. Chromatograms were scanned for the presence of Phase-I and Phase-II metabolites and tentatively identified based on mass accuracy of the molecular formula, isotopic pattern, and MS/MS spectra. The two major metabolites of TBOEP were products of O-dealkylation and of hydroxylation, respectively. TPHP was mainly transformed to its diester metabolite by O-dearylation and to a hydroxylated metabolite. TCEP was poorly metabolized into its diester and a product of oxidative dehalogenation. The major metabolite of TCIPP was a product of oxidative dehalogenation. TDCIPP was mainly transformed into its diester and a glutathione S-conjugate. The metabolites identified in the present study are candidate biomarkers for future human biomonitoring studies.
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