1,2,3-benzotriazole, with the chemical formula C6H5N3, is a heterocyclic molecule with three nitrogen atoms. There are numerous applications for this polar, colorless aromatic molecule.

Metabolism / Metabolites
Benzotriazoles (BTs) are exogenous pollutants widely distributed in aquatic environments. Due to their polarity, recalcitrant nature, and widespread applications, they have become a growing concern. In some water recycling activities, such as rainwater bioretention or the use of reclaimed water for crop irrigation, BTs come into contact with plants, providing potential exposure pathways for consumers. We found that in hydroponic systems, Arabidopsis plants can rapidly absorb (approximately 1 log unit per day) BT and metabolize it into novel BT metabolites structurally similar to plant hormones such as tryptophan and auxin; less than 1% of BT remains in the form of the parent compound. Using LC-QTOF-MS untargeted metabolomics, we identified two major BT transformation products: glycosylated products and products incorporated into the tryptophan biosynthesis pathway. BT amino acid metabolites are structurally similar to the storage forms of tryptophan and auxin, plant hormones. Key intermediates were synthesized (and identified by 1H/13C NMR) for product validation. In time-weighted equilibrium after multiple exposures, the three major metabolites accounted for over 60% of the total BT. Glycosylated BT was secreted into the hydroponic medium by plants, a phenomenon previously unobserved. The observed amino acid metabolites may be formed by tryptophan biosynthesizers replacing natural indole molecules with synthetic BT, potentially producing plant hormone analogs. These results suggest that plant metabolism of BT may mask the presence of BT pollution in the environment. Furthermore, BT-derived metabolites are structurally related to plant auxin hormones, and their adverse biological effects should be assessed. 1-H-benzotriazole is metabolized in vitro by rat liver microsomes to 4-hydroxybenzotriazole and 5-hydroxybenzotriazole.

Toxicity Summary
Identification and Uses: 1,2,3-Benzotriazole (BT) is a white to light brown crystalline powder. It is used as a photographic limiter and chemical intermediate. It is also used as a corrosion inhibitor in industrial water treatment and as a treatment for bronze erosion in the restoration of metal artworks. Human Studies: One report shows that two metalworkers developed contact dermatitis after exposure to lubricating oil containing BT. Animal Studies: In primary irritation and sensitization tests on guinea pig skin, BT showed only mild irritation at concentrations up to 50% ethanol and was not sensitizing. The dry powder was severely irritating to rabbit eyes (0.1 mL unwashed), but immediate rinsing with water significantly reduced the irritation. BT was positive in mutagenicity tests against Salmonella Typhimurium and Escherichia coli. Ecotoxicity Studies: This chemical has been widely detected in aquatic environments and exhibits some environmental persistence. BT exposure can have negative effects on the endocrine system and may cause neurotoxicity in fish. BT has shown hepatotoxicity and neurotoxicity in the rare Chinese flounder. In female marine killifish, exposure to 0.01 mg/L BT significantly altered the expression levels of vitellogenin, CYP1A1, and CYP19a. In vitro assays using recombinant yeast (anti)estrogens demonstrated that BT possesses significant anti-estrogenic properties. Plant metabolism of BT may mask the presence of BT pollution in the environment. Furthermore, BT-derived metabolites are structurally related to plant growth hormones.

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Toxicity Data
LC50 (rat) = 1,910 mg/m3/3H

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Interactions
Benzotriazole (BTR) is an emerging environmental pollutant widely used in industrial applications and household detergents. Although BTR has been reported to be toxic to aquatic organisms, its effects on terrestrial invertebrates are poorly understood. Copper (Cu) accumulates in farmland soils receiving municipal waste, fertilizers, fungicides, and urban sewage. This study employed two different bioassay methods (acute toxicity test and behavioral toxicity test) to evaluate the toxicity of Cu and BTR, alone and in combination, to earthworms (Eisenia fetida) in artificial soil. Avoidance behavior tests showed that the EC50 (48-hour) values of Cu and BTR were 1.47 and 0.46 mmol/kg, respectively. Acute toxicity tests showed that the LC50 (7-day) and LC50 (14-day) values of Cu in earthworms were 9.19 and 5.28 mmol/kg, respectively, while the LC50 (7-day) and LC50 (14-day) values of BTR were 2.43 and 1.76 mmol/kg, respectively. Toxicity analysis indicated that the binary mixture of BTR and Cu had a significant antagonistic effect on earthworm avoidance behavior and survival rate. With increasing BTR concentration, the activity and mortality of Cu²⁺ in earthworms significantly decreased, while the solid-liquid partition coefficient of Cu increased. These results suggest that the presence of BTR can reduce the toxicity and bioavailability of copper in soil.
As an emerging pollutant, 1-H-benzotriazole (1H-BTR) has been detected in both artificial and natural aquatic environments, often coexisting with heavy metals and causing complex pollution. This study investigated the acute toxicity of cadmium (Cd) and 1H-BTR, as well as their individual and combined hepatotoxicity, using wild-type and transgenic zebrafish (Danio rerio). Although 1H-BTR showed low acute toxicity in zebrafish, increased expression of liver-specific fatty acid-binding proteins was observed after transgenic zebrafish embryos were exposed to 5.0 μM 1H-BTR for 30 days. Furthermore, co-exposure to 1H-BTR and cadmium not only reduced the acute toxicity caused by cadmium but also mitigated cadmium-induced liver atrophy in transgenic fish. Accordingly, this study also investigated the effects of co-exposure to 1H-BTR and cadmium on the expression of genes related to multiple cadmium-induced signaling pathways, as well as superoxide dismutase and glutathione S-transferase proteins. Based on the determination of cadmium bioaccumulation in fish and the complexation stability constant (β) of cadmium-BTR complexes in solution, the detoxification mechanism of coexisting 1H-BTR on cadmium in zebrafish was investigated.

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Non-human toxicity values
Rat inhalation LC50: 1900 mg/m³/hr
Rat oral LD50: 600 mg/kg
Mouse oral LD50: 615 mg/kg
Mouse intraperitoneal injection LD50: 400 mg/kg
For more complete non-human toxicity data for 1,2,3-benzotriazoles (6 in total), please visit the HSDB record page.

1,2,3-Benzotriazole is a white to light brown crystal or white powder, odorless. (NTP, 1992)
Benzotriazole is the simplest member of the benzotriazole class of compounds, its structure consisting of a benzene ring fused with a 1H-1,2,3-triazole ring. It is an environmental pollutant and an exogenous substance.

C6H5N3

119.12

119.048

95-14-7

1H-Benzotriazole-4,5,6,7-d4;1185072-03-0

7220

Needles from chloroform or benzene
White to light tan, crystalline powder

1.3±0.1 g/cm3

204 ºC (15 mmHg)

97-99 °C(lit.)

170 ºC

0.0±0.8 mmHg at 25°C

1.715

1.34

1

2

0

9

92.5

0

N1NC2C(=CC=CC=2)N=1

QRUDEWIWKLJBPS-UHFFFAOYSA-N

InChI=1S/C6H5N3/c1-2-4-6-5(3-1)7-9-8-6/h1-4H,(H,7,8,9)

2H-benzotriazole

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)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*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.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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