The Tire-Derived Chemical 6PPD-quinone Is Lethally Toxic to the White-Spotted Char Salvelinus leucomaenis pluvius but Not to Two Other Salmonid Species

Environmental Science & Technology Letters, Год журнала: 2022, Номер 9(12), С. 1050 - 1055

Опубликована: Ноя. 7, 2022

N-(1,3-Dimethylbutyl)-N′-phenyl-p-phenylenediamine-quinone, also known as 6PPD-quinone (6PPD-Q), was recently identified the toxic chemical that causes acute mortality in coho salmon following exposure to urban road runoff. Subsequent studies found there were large differences sensitivity 6PPD-Q (>100-fold) even among salmonid species. Here we performed 96 h toxicity tests of with three species (Salvelinus leucomaenis pluvius, Salvelinus curilus, and Oncorhynchus masou masou) lethally S. pluvius a 24 median lethal concentration (LC50) 0.51 μg/L but not other two at environmentally relevant concentrations (<3.8 μg/L). In addition, measured suspected monohydroxylated metabolite brain gill tissues for The internal (ILC50) estimated be 4.0 μg/kg wet weight 6.2 while tissue surviving exceeded ILC50 values pluvius. These results suggest might affected by toxicodynamic factors well toxicokinetics.

Язык: Английский

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Widespread N-(1,3-Dimethylbutyl)-N′-phenyl-p-phenylenediamine Quinone in Size-Fractioned Atmospheric Particles and Dust of Different Indoor Environments

Environmental Science & Technology Letters, Год журнала: 2022, Номер 9(5), С. 420 - 425

Опубликована: Апрель 25, 2022

Transformed from the antioxidant N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine (6-PPD), emerging toxicant 6-PPD quinone (6-PPDQ) has received extensive attention because of its potential toxic effects. However, evidence on size distribution patterns atmospheric particles and environmental occurrence remains limited. We determined 6-PPDQ pollution levels in eight size-segregated (0.43–10 μm) four waste recycling plants dust samples six typical indoor compartments South China. tended to accumulate coarse (9–10 with highest concentrations (7.78–23.2 pg m–3). Model simulations revealed that deposition efficiency (flux) particle-bound were 89%–91% (10.8–39.1 h–1), 3.2%–3.8% (0.45–1.64 6.0%–6.9% (0.80–2.85 h–1) workers' head airways, tracheobronchial, pulmonary alveoli areas respiratory tracts, respectively. The matrix was not main carrier 6-PPDQ, lower multiple environments than those suspended air particles. In-vehicle rubber-related places seemed be most polluted by this ozone-initiated quinone. Our study further enriches knowledge ubiquitous distributions 6-PPDQ. Additional toxicity experiments should conducted using based high exposure risk for humans upper tract via inhalation.

Язык: Английский

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Chiral perspective evaluations: Enantioselective hydrolysis of 6PPD and 6PPD-quinone in water and enantioselective toxicity to Gobiocypris rarus and Oncorhynchus mykiss

Environment International, Год журнала: 2022, Номер 166, С. 107374 - 107374

Опубликована: Июнь 27, 2022

As a ubiquitous tire antidegradant, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD) is persistently released into the environment. It highly toxic to aquatic organisms, and its transformation product 6PPD-quinone (6PPD-Q), "very toxic" Oncorhynchus kisutch at median lethal concentration (LC50) of < 0.1 ng/mL. Notably, 6PPD 6PPD-Q are chiral compounds. Here, enantioselective evaluations, including hydrolysis acute toxicity were conducted after preparing enantiomer, confirming enantiomer absolute configuration establishing enantioseparation methods. In experiments, products 6PPD-Q, phenol, 4-[(1,3-dimethylbutyl)amino]- (4-DBAP) 4-hydroxydiphenylamine (4-HDPA) detected. different water solutions, 4-DBAP 4-HDPA was very fast (0.87-107 h), while half-lives (12.8-16.3 d) significantly longer than (4.83-64.1 h). At enantiomeric level, no conversion occurred. R-6PPD generated R-6PPD-Q, S-6PPD S-6PPD-Q, formation rate S-6PPD-Q 1.77 times faster R-6PPD-Q. terms toxicity, China-specific Gobiocypris rarus (LC50, 162-201 ng/mL), it had difference. 1.66-4.31 ng/mL) mykiss, which commercial importance, toxicities rac-6PPD-Q 1.9 2.6 higher Furthermore, concentrations R-6PPD-Q in solutions LC50 values O. species-specific, should raise concern. These results provide important information for environmental risk assessments especially from perspective enantiomers.

Язык: Английский

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Tire-rubber related pollutant 6-PPD quinone: A review of its transformation, environmental distribution, bioavailability, and toxicity

Journal of Hazardous Materials, Год журнала: 2023, Номер 459, С. 132265 - 132265

Опубликована: Авг. 15, 2023

Язык: Английский

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Transformation Product Formation upon Heterogeneous Ozonation of the Tire Rubber Antioxidant 6PPD (N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine)

Environmental Science & Technology Letters, Год журнала: 2022, Номер 9(5), С. 413 - 419

Опубликована: Апрель 12, 2022

Transformation products (TPs) originating within tire tread wear particles (TWPs) are likely pervasive contaminants of roadway environments although their formation, fate, and risks poorly characterized. Here, we investigated TP formation occurring during heterogeneous reaction gas-phase ozone with the common rubber antioxidant 6PPD (N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine); exposures included both pure compound TWP rubbers. Oxidative transformation occurred ozonation (∼360 ppbv), up to 81% mass reacting over 6 h. Conversion 6PPD-quinone (6PPDQ)─a recently reported highly toxic TP─was confirmed at a 9.7% molar yield for 0.95% present TWPs, representing minima these time scales conditions. Leveraging high-resolution spectrometry, identified 19 probable 6PPD-derived TPs in ozonated samples, underscoring diverse from this antioxidant. By screening environmental nine were detected runoff. The data confirm that when antioxidants react ozone, as intended, they form release various surrounding environments.

Язык: Английский

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Transformation Products of Tire Rubber Antioxidant 6PPD in Heterogeneous Gas-Phase Ozonation: Identification and Environmental Occurrence

Environmental Science & Technology, Год журнала: 2023, Номер 57(14), С. 5621 - 5632

Опубликована: Март 30, 2023

6PPD, a tire rubber antioxidant, poses substantial ecological risks because it can form highly toxic quinone transformation product (TP), 6PPD-quinone (6PPDQ), during exposure to gas-phase ozone. Important data gaps exist regarding the structures, reaction mechanisms, and environmental occurrence of TPs from 6PPD ozonation. To address these gaps, ozonation was conducted over 24–168 h were characterized using high-resolution mass spectrometry. The probable structures proposed for 23 with 5 subsequently standard-verified. Consistent prior findings, 6PPDQ (C18H22N2O2) one major in (∼1 19% yield). Notably, not observed 6QDI (N-(1,3-dimethylbutyl)-N′-phenyl-p-quinonediimine), indicating that formation does proceed through or associated TPs. Other included multiple C18H22N2O C18H22N2O2 isomers, presumptive N-oxide, N,N′-dioxide, orthoquinone structures. Standard-verified quantified roadway-impacted samples, total concentrations 130 ± 3.2 μg/g methanol extracts tread wear particles (TWPs), 34 4 μg/g-TWP aqueous TWP leachates, 2700 1500 ng/L roadway runoff, 1900 1200 creeks. These demonstrate are likely an important ubiquitous class contaminants environments.

Язык: Английский

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Exposure to 6-PPD Quinone at Environmentally Relevant Concentrations Causes Abnormal Locomotion Behaviors and Neurodegeneration in Caenorhabditis elegans

Environmental Science & Technology, Год журнала: 2023, Номер 57(12), С. 4940 - 4950

Опубликована: Март 13, 2023

6-PPD quinone (6-PPDQ) can be transformed from through ozonation. Nevertheless, the potential neurotoxicity of 6-PPDQ after long-term exposure and underlying mechanism are largely unclear. In Caenorhabditis elegans, we here observed that 0.1–10 μg/L caused several forms abnormal locomotion behaviors. Meanwhile, neurodegeneration D-type motor neurons was in 10 6-PPDQ-exposed nematodes. The associated with activation Ca2+ channel DEG-3-mediated signaling cascade. this cascade, expressions deg-3, unc-68, itr-1, crt-1, clp-1, tra-3 were increased by 6-PPDQ. Moreover, among genes encoding neuronal signals required for control stress response, jnk-1 dbl-1 decreased 6-PPDQ, daf-7 glb-10 RNAi jnk-1, dbl-1, daf-7, resulted susceptibility to toxicity decreasing locomotory ability inducing neurodegeneration, suggesting JNK-1, DBL-1, DAF-7, GLB-10 also induction neurotoxicity. Molecular docking analysis further demonstrated binding DEG-3, GLB-10. Together, our data suggested risk at environmentally relevant concentrations causing organisms.

Язык: Английский

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Screening p-Phenylenediamine Antioxidants, Their Transformation Products, and Industrial Chemical Additives in Crumb Rubber and Elastomeric Consumer Products

Environmental Science & Technology, Год журнала: 2023, Номер 57(7), С. 2779 - 2791

Опубликована: Фев. 9, 2023

Recently, roadway releases of

Язык: Английский

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Environmental Occurrence and Toxicity of 6PPD Quinone, an Emerging Tire Rubber-Derived Chemical: A Review

Environmental Science & Technology Letters, Год журнала: 2023, Номер 10(10), С. 815 - 823

Опубликована: Сен. 1, 2023

N-(1,3-Dimethylbutyl)-N′-phenyl-p-phenylenediamine (6PPD) is a chemical added to tires prevent their oxidative degradation. 6PPD highly reactive with ozone and oxygen, leading the formation of transformation products such as quinone (6PPDQ) on tire surfaces and, subsequently, in road wear particles. 6PPDQ toxicant that has been found roadway runoff receiving water systems. Its presence municipal stormwater led acute mortality coho salmon during migration urban creeks reproduce, generating global interest studying its occurrence toxicity environment. This review aims provide critical overview current state knowledge 6PPDQ, assisting researchers policymakers understanding potential impacts this emerging environment human health. As there are many unanswered questions surrounding further research needed. highlights importance including regulations for 6PPD, well all synthetic chemicals concern.

Язык: Английский

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Acute Toxicity of 6PPD‐Quinone to Early Life Stage Juvenile Chinook (Oncorhynchus tshawytscha) and Coho (Oncorhynchus kisutch) Salmon

Environmental Toxicology and Chemistry, Год журнала: 2023, Номер 42(4), С. 815 - 822

Опубликована: Янв. 24, 2023

Abstract The breakdown product of the rubber tire antioxidant N ‐(1,3‐dimethylbutyl)‐ N' ‐phenyl‐ p ‐phenylenediamine‐quinone (6PPD)‐6‐PPD‐quinone has been strongly implicated in toxic injury and death coho salmon ( Oncorhynchus kisutch ) urban waterways. Whereas recent studies have reported a wide range sensitivity to 6PPD‐quinone several fish species, little is known about risks Chinook tshawytscha ), primary prey endangered Southern Resident killer whales Orcinus orca subject much concern. face numerous conservation threats Canada United States, with many populations assessed as either or threatened. We evaluated acute toxicity newly feeding (~3 weeks post swim‐up) juvenile coho. Juvenile were exposed for 24 h under static conditions five concentrations 6PPD‐quinone. 3 orders magnitude more sensitive compared Chinook, 24‐h median lethal concentration (LC50) estimates 41.0 than 67 307 ng/L, respectively. LC50 was 2.3‐fold lower what previously 1+‐year‐old (95 ng/L), highlighting value evaluating age‐related differences this tire‐related chemical. Both species exhibited typical symptomology (gasping, increased ventilation, loss equilibrium, erratic swimming), that symptomatic generally exhibiting mortality. values derived from our study are below measured salmon‐bearing waterways, suggesting potential population‐level consequences waters. higher relative merits further investigation, including population‐relevant sublethal effects. Environ Toxicol Chem 2023;42:815–822. © 2023 His Majesty King Right Authors. Environmental Toxicology Chemistry published by Wiley Periodicals LLC on behalf SETAC. Reproduced permission Minister Fisheries Oceans Canada.

Язык: Английский

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