Absorption, Distribution and Excretion
This study aimed to investigate the percutaneous absorption of JP-8 through porcine ear skin and human skin in vitro, and to examine the effects of JP-8 exposure on the skin barrier function and irritation of Yucatan miniature pigs. In vitro percutaneous absorption studies used excised porcine ear skin and human skin, employing JP-8 solutions containing 5.0 μCi radiolabeled tridecane, nonane, naphthalene, or toluene (specific components of JP-8). In in vivo studies, 250 μL of JP-8 or two of its components (toluene or nonane) was placed in a Hill top chamber® and applied to the labeled treatment area for 24 hours. Transdermal water loss (TEWL), skin capacitance (water content), and skin irritation (erythema and edema) were assessed before treatment and at 1, 2, and 24 hours after patch removal. Components of JP-8, such as tridecane, nonane, naphthalene, and toluene, significantly penetrated porcine ear skin and human skin, with the penetration rate proportional to their composition in JP-8. Steady-state flux values of tridecane showed no significant difference between porcine ear skin and human skin (P>0.05). Although there were statistically significant differences in the steady-state flux values of nonane, naphthalene, and toluene between porcine and human skin (P<0.01), these values remained close, considering the large variability typically observed in transdermal absorption studies. Application of toluene, nonane, or JP-8 all increased TEWL, with JP-8 showing the strongest effect (TEWL was 3.5 times the baseline level at 24 hours). Skin moisture content decreased after JP-8 application, but the difference was not significant compared to baseline (P>0.05). JP-8 caused moderate erythema and moderate to severe edema. Although edema subsided after 24 hours, the degree of erythema remained essentially unchanged over 24 hours. JP-8 caused stronger skin irritation than pure toluene or nonane. Transdermal water loss (TEWL) data for toluene, nonane, and JP-8 correlated well with skin irritation data (erythema and edema). JP-8 contains hundreds of aliphatic and aromatic hydrocarbons. Exposure to this substance leads to significant alterations in skin barrier function, manifested as increased transepidermal water loss (TEWL), and in miniature pigs, it causes marked erythema and edema. Furthermore, as evidenced by increased TEWL following JP-8 exposure, disruption of the skin barrier function may lead to increased permeability of JP-8 components and/or other chemicals exposed to the skin. This study further confirms that pig ear skin can serve as a model for predicting the rate of chemical permeation through human skin. Despite the global use of over 4.5 billion gallons of JP-8 annually by governments and industry, little is known about the mechanisms of skin permeation and absorption of jet fuels, particularly JP-8. Routes of exposure to JP-8 include vapor, liquid, and aerosol. Inhalation and skin contact are the most common routes. Repeated or prolonged exposure to JP-8 may cause irritation, but it remains unclear whether skin permeation of the fuel leads to systemic toxicity. This study aimed to measure the permeation and absorption of JP-8 and its main components on rat skin to assess its potential impact on human exposure. We used a static diffusion cell to measure the transdermal flux of JP-8 and its components, as well as skin absorption kinetics. The total flux of hydrocarbon components was 20.3 μg/cm²/h. Thirteen components of JP-8 permeated into the receptor solution. The flux ranged from a high of 51.5 μg/cm²/h (additive diethylene glycol monomethyl ether) to a low of 0.334 μg/cm²/h (tridecane). Aromatic components permeated the fastest. Six components (all aliphatic) were detected in the skin. The concentrations absorbed by the skin after 3.5 hours ranged from 0.055 μg/g skin (tetradecane) to 0.266 μg/g skin (undecane). These results indicate that (1) the permeation of JP-8 does not cause systemic toxicity due to the low flux of all components; and (2) the absorption of aliphatic components by the skin may be one of the causes of skin irritation. The partition coefficients (PCs) of octane, nonane, decane, undecane, and dodecane (n-C8 to n-C12 n-alkanes) in rat tissue/air and blood/air were determined using the vial equilibration method. The blood/air PC values for n-C8 to n-C12 alkanes were 3.1, 5.8, 8.1, 20.4, and 24.6, respectively. The lipophilicity of n-alkanes increased with increasing carbon chain length, indicating that lipophilicity is a significant determinant of the blood/air PC value for n-alkanes. The PC values for muscle/blood, liver/blood, brain/blood, and fat/blood were: octane (1.0, 1.9, 1.4, and 247), nonane (0.8, 1.9, 3.8, and 274), decane (0.9, 2.0, 4.8, and 328), undecane (0.7, 1.5, 1.7, and 529), and dodecane (1.2, 1.9, 19.8, and 671). The tissue/blood PC value was highest in fat and lowest in muscle. The brain/air PC value for undecane was inconsistent with the PC values for other n-alkanes. Using the measured partition coefficients of these n-alkanes, linear regression was employed to predict the tissue (excluding brain tissue) and blood/air partition coefficients of larger-chain n-alkanes (tetane, tetradecane, pentadecane, hexadecane, and heptadecane, i.e., n-C13 to n-C17). The measured tissue/air and blood/air partition coefficients for n-C8 to n-Cl2 showed good agreement with the predicted values, enhancing our confidence in the prediction of long-chain n-alkanes partition coefficients. ...This study aimed to evaluate the dose-related transdermal absorption of various aliphatic and aromatic hydrocarbons. The first treatment (1X) was prepared in a porcine skin flowing diffusion cell using hexadecane solvent, containing undecane (4.1%), dodecane (4.7%), tridecane (4.4%), tetradecane (3%), pentadecane (1.6%), naphthalene (1.1%), and dimethylnaphthalene (1.3% of the jet fuel). Other treatments (n = 4 cells) were prepared at concentrations of 2X and 5X. Perfusion fluid samples were analyzed using headspace solid-phase microextraction fiber technology via gas chromatography-flame ionization detector (GC-FID). We standardized the detection method to ensure good linear correlation of all test components with culture medium standards. We estimated the absorption parameters for all tested hydrocarbons, including diffusion coefficient, permeability coefficient, steady-state flux, and percentage of absorbed dose. This method provides a baseline for assessing interactions between components and between components and diluents (solvents). We established a quantitative structure-activity relationship (QSPR) model to predict the permeability of unknown aviation kerosene hydrocarbons in this solvent system using their physicochemical parameters. The results showed that the absorption rates of naphthalene and dimethylnaphthalene (DMN) were positively correlated with dose. More absorption, distribution, and excretion (ADEC) data for n-tetanes (10 in total) can be found on the HSDB record page. Metabolites/Metabolites: Alternative fuels are being considered in both civilian and military applications. One of these is S-8, an alternative aviation kerosene synthesized via the Fischer-Tropsch synthesis. It contains no aromatic compounds and is primarily composed of straight-chain and branched alkanes. No metabolites of S-8 fuel have yet been identified in experimental animals. This study aimed to identify metabolites in male Fischer 344 rats exposed to aerosol S-8 and a designed mixture of straight-chain alkane/polycyclic aromatic hydrocarbons (decane, undecane, dodecane, tridecane, tetradecane, pentadecane, naphthalene, and 2-methylnaphthalene). Blood and tissue samples were collected, and 70 straight-chain and branched alcohols and ketones with 7 to 15 carbon atoms were analyzed. No fuel metabolites were detected in blood, lung, brain, or adipose tissue after exposure to S-8. Metabolites were detected in liver, urine, and feces. Most metabolites were alcohols and ketones at the 2 and 3 positions of the main hydrocarbon compounds, with only trace amounts at the 1 or 4 positions. After exposure to the alkane mixture, metabolites were detected in blood, liver, and lung tissue. Interestingly, re-metabolites (3-tetranone, 2-tetranol, and 2-tetradecanool) were observed only in lung tissue, which may indicate that metabolism occurs in the lungs. Apart from these re-metabolites, the metabolic profile observed in this study is consistent with previously reported findings on single alkane metabolism. Further investigation is needed to determine potential metabolic interactions between parent, primary, and secondary metabolites and to identify more polar metabolites. Some metabolites may have potential use as biomarkers of fuel exposure. This study investigated the effects of culture conditions on inosine production in the adenine auxotrophic strain Corynebacterium rockophile SB 4082. Inosine production depends on the adenine content in the culture medium. The optimal conditions for inosine production were achieved by adding 10 mg of adenine and 0.5 g of yeast extract to 100 mL of medium. Ammonium chloride or ammonium sulfate were both effective nitrogen sources. Tridecane was used as a carbon source.

Toxicity Summary
Identification and Uses: Tridecane is a colorless liquid. It is used in organic synthesis, aviation fuel research, paraffin product manufacturing, the rubber industry, the paper industry, and as a solvent and distillation aid. Human Exposure and Toxicity: During industrial use, tridecane may cause harm through inhalation, ingestion, or skin absorption. Animal Studies: In a swine skin irritation study, significant erythema was observed after repeated daily exposure for four consecutive days. In rabbit skin exposure, tridecane caused greater increases in temperature and capacitance at all time points than any other component of JP-8 aviation fuel. Mice treated with tridecane developed tumors on their backs after exposure to ultraviolet radiation at wavelengths greater than 350 nm (generally considered non-carcinogenic). Inhalation into the lungs: Tridecane is an asphyxiating substance. It can cause death and chemical pneumonia. The following genotoxicity studies were negative: cell transformation and co-transformation with benzo[a]pyrene in Syrian hamster embryonic cells, and intercellular communication in Syrian hamster embryonic cells.

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Toxicity Data
LC50 (Rat)>41 ppm/8H

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Non-human Toxicity Values
LD50 (Mice, Intravenous Injection) 1161 mg/kg

[1]. Influence of Winemaking Processing Steps on the Amounts of (E)-2-Decenal and Tridecane as Off-Odorants Caused by Brown Marmorated Stink Bug (Halyomorpha halys). J Agric Food Chem. 2017 Feb 1;65(4):872-878.

[2]. The effect of pressure on the phase transition behavior of tridecane, pentadecane, and heptadecane: a Fourier transform infrared spectroscopy study. J Chem Phys. 2011 Apr 14;134(14):144503.

Tridecane is an oily, pale yellow, transparent liquid with a hydrocarbon odor. Its flash point is 190-196 °F (88-90 °C). Its specific gravity is 0.76. Its boiling point is 456 °F (230 °C). Repeated or prolonged skin contact may cause irritation or redness, and may develop into dermatitis. Exposure to high concentrations of its vapor may cause headaches and coma. Tridecane is a straight-chain alkane containing 13 carbon atoms. It is a component of essential oils extracted from plants such as okra. It is both a plant metabolite and a volatile oil component. Tridecane has been reported to be present in camellia, neem, and other organisms with relevant data.

C13H28

184.36

184.219

629-50-5

Tridecane-d28; 121578-12-9

12388

Colorless to light yellow liquid

0.756 g/mL at 25 °C(lit.)

110-112 °C12 mm Hg(lit.)

−6-−4 °C(lit.)

215 °F

1 mm Hg ( 59.4 °C)

n20/D 1.425(lit.)

5.317

0

0

10

13

66.1

0

C([H])([H])(C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H]

IIYFAKIEWZDVMP-UHFFFAOYSA-N

InChI=1S/C13H28/c1-3-5-7-9-11-13-12-10-8-6-4-2/h3-13H2,1-2H3

tridecane

Tridecane

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Ethanol: 100 mg/mL (542.42 mM)
DMSO: 100 mg/mL (542.42 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (13.56 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (13.56 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 3: ≥ 2.5 mg/mL (13.56 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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Solubility in Formulation 4: ≥ 1.25 mg/mL (6.78 mM) (saturation unknown) in 10% EtOH + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 12.5 mg/mL clear EtOH stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 5: ≥ 1.25 mg/mL (6.78 mM) (saturation unknown) in 10% EtOH + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 12.5 mg/mL clear EtOH stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)