Research use only ✓ COA Bacteriostatic Water

Lab Supplies

Bacteriostatic Water BAC water

Name: Bacteriostatic Water
Brand: Clean Peptide
SKU: bacteriostatic-water
Price: 14.00 USD
Availability: InStock

BATCH BAC-0023530

Bac water (bacteriostatic water) is sterile water with 0.9% benzyl alcohol added as a preservative, so one vial can be entered more than once. Clean Peptide sells it for laboratory use in 3 ml and 10 ml vials. What is bac water? "Bac water" is the short name for bacteriostatic water: water containing a small amount of benzyl alcohol, a preservative that suppresses bacterial growth. That preservative is the only thing that separates it from plain sterile water, and it is the reason a bacteriostatic vial is made as a multiple-dose container rather than for a single use.

Mass

Clear

Quantity

−30% applied

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Verified test results

Every batch, independently verified.

Each batch is analyzed by an ISO/IEC 17025 accredited third-party laboratory before it ships. This is the released report for the size selected above, exactly as the lab signed it.

Accurate Test LabsIndependent, ISO/IEC 17025 accredited

Certificate of analysis

0.50 EU/ml

Endotoxin

Lot: BAC-0023530
Tested: Jul 22, 2026
Labeled: 3ml

ISO 17025 accredited

Full QC panel

1 passed

Endotoxin

limit 350.00

0.50 EU/mlPass

Every size on record

Open any size’s signed certificate. Your order ships with the report for the size you buy.

Bacteriostatic Water 3ml

Selected

LOT BAC-0023530

Labeled: 3ml
Endotoxin: 0.50 EU/ml
Tested: Jul 22, 2026

1 assay passed · Accurate Test Labs, ISO/IEC 17025 accredited

Bacteriostatic Water 10ml

Selected

LOT BAC-0023530

Labeled: 10ml
Endotoxin: 0.50 EU/ml
Tested: Jul 22, 2026

1 assay passed · Accurate Test Labs, ISO/IEC 17025 accredited

What is bac water?

“Bac water” is the short name for bacteriostatic water: water containing a small amount of benzyl alcohol, a preservative that suppresses bacterial growth. That preservative is the only thing that separates it from plain sterile water, and it is the reason a bacteriostatic vial is made as a multiple-dose container rather than for a single use.

The benzyl alcohol is not there to do anything chemically to what it is mixed with. It keeps the water itself from supporting bacterial growth between uses. That is why bacteriostatic water is the diluent most often stocked alongside lyophilised research peptides.

Bacteriostatic water specification

Product	Bacteriostatic water (bac water)
Composition	Sterile water with 0.9% benzyl alcohol as a bacteriostatic preservative
Preservative	Benzyl alcohol (phenylmethanol), C₇H₈O, 108.14 g/mol, CAS 100-51-6
Sizes	3 ml and 10 ml vials
Container	Multiple-dose vial
Certificate	Endotoxin report for the current lot (below)
Intended use	Laboratory use only

Benzyl alcohol identity: PubChem CID 244.

Certificate for the current lot

The current lot of bac water, BAC-0023530, was tested for bacterial endotoxin. The certificate reports a single result, endotoxin, against the limit printed on the report:

Size	Lot	Laboratory	Analysed	Result
3ml	BAC-0023530	Accurate Test Labs	22 Jul 2026	Endotoxin: 0.50 EU/ml · limit 350.00
10ml	BAC-0023530	Accurate Test Labs	22 Jul 2026	Endotoxin: 0.50 EU/ml · limit 350.00

Transcribed from the certificate issued for each size on sale today. Open the signed certificate for any size under Verified test results above. Every Bacteriostatic Water COA, lot by lot

The report covers endotoxin only. It does not state a purity figure, so this page does not show one.

Bacteriostatic water vs sterile water

The three diluents below are often confused. The differences are composition and how many times a container is meant to be opened.

	Bacteriostatic water	Sterile water	Bacteriostatic sodium chloride
What it is	Water with benzyl alcohol preservative	Water with no preservative	0.9% sodium chloride (saline) with benzyl alcohol preservative
Preservative	Benzyl alcohol, 0.9%	None	Benzyl alcohol, 0.9%
Container	Multiple-dose	Single-dose	Multiple-dose
Contains salt	No	No	Yes, 9 mg/mL

For reference, the FDA-registered labelling for the pharmaceutical product “Bacteriostatic Water for Injection, USP” describes it as water containing 0.9% (9 mg/mL) benzyl alcohol, supplied in a multiple-dose container, with a pH of 5.7 (4.5 to 7.0). The same labelling states that benzyl alcohol has been associated with toxicity in neonates and carries the warning “Not for use in neonates”. Source: DailyMed label, Bacteriostatic Water for Injection, USP; DailyMed label, Bacteriostatic 0.9% Sodium Chloride Injection, USP.

Clean Peptide’s bac water is sold as a laboratory supply. It is not that labelled pharmaceutical product, and it is not for human or veterinary use.

Where to buy bacteriostatic water

You can buy bacteriostatic water here in two sizes, 3 ml and 10 ml, priced on this page. It ships with the rest of an order from the same catalogue as our research peptides, and every peptide in that catalogue has its own certificate of analysis on its product page.

BPC-157, TB-500 and the BPC-157 / TB-500 blend
GLP-3 Reta (retatrutide) and GLP-2 Tirz (tirzepatide)
GHK-Cu, KLOW and KPV
All lab supplies

Before you buy any vial, it is worth knowing what its certificate should show: see how to read a peptide certificate of analysis.

Technical specification

What is on file, and how it is handled

Every figure below is transcribed from the paperwork for this compound.

Material

Compound: Bacteriostatic Water
Class: Laboratory diluent
Form: Solution: water with 0.9% benzyl alcohol
Sizes: 3ml, 10ml

Verification

Identity: Not tested on the current certificate
Purity: See certificate
Batch: BAC-0023530
Documentation: Per-batch certificate of analysis

Handling

Storage: Store at −20 °C, protected from light
Intended use: In-vitro laboratory research only

QuestionsBacteriostatic Water: frequently asked

What is bac water?+

Bac water is bacteriostatic water: sterile water with 0.9% benzyl alcohol added as a preservative, which lets a vial be entered more than once.

What is in bacteriostatic water?+

Water and benzyl alcohol at 0.9%. Benzyl alcohol (C7H8O, CAS 100-51-6) is the bacteriostatic preservative; nothing else is added.

What sizes of bac water does Clean Peptide sell?+

3 ml and 10 ml vials. Both sizes are on this page with their current prices.

Is bacteriostatic water the same as sterile water?+

No. Sterile water has no preservative and is meant for a single use. Bacteriostatic water contains 0.9% benzyl alcohol so the vial can be used more than once.

How is this bac water tested?+

The current lot, BAC-0023530, has an endotoxin report from Accurate Test Labs: 0.50 EU/mL against a limit of 350 EU/mL. The report covers endotoxin only.

Is Clean Peptide's bac water for human use?+

No. It is sold as a laboratory supply, not as the pharmaceutical product Bacteriostatic Water for Injection, USP, and it is not for human or veterinary use.

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