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ng/g to PPB Converter

↔ Convert ppb to ng/g instead

Common Conversions

ng/g ppb
0.1 0.1
1 1
5 5
10 10
50 50
100 100
500 500
1000 1000
5000 5000
10000 10000
100000 100000
1000000 1000000

Why this conversion matters in chemistry

For solid and tissue samples, ng/g and ppb describe the same mass ratio. Both are nanograms of analyte per 10⁹ ng of sample. A 25 ng/g PCB result on a fish-tissue composite is 25 ppb on a regulatory consumption advisory — same number, two unit conventions. The identity rests on the mass per mass framing; for liquid samples reported in ng/mL, the equivalence depends on density. Trace residue analysis runs almost entirely at this scale, which is why the two notations stay interchangeable in environmental and food-chemistry work.

Formula

ppb = ng/g × 1

Worked Examples

1 ng/g = 1 ppb

The identity itself — one nanogram per gram is one part per 10⁹ by mass.

10 ng/g = 10 ppb

A trace contaminant at the low end of routine analytical detection in a solid matrix.

100 ng/g = 100 ppb

An elevated contaminant level — well above background for many regulated trace analytes in food or sediment.

1000 ng/g = 1000 ppb

Equivalently 1 ppm or 1 mg/kg — the boundary where the next prefix up becomes more readable.

Frequently Asked Questions

Are ng/g and ppb the same?
For mass per mass measurements, yes. One ng per gram of sample is one part per billion by mass — exactly. The identity is built into the unit definitions.
When does ng/g notation make sense?
When the sample is a solid weighed in grams — soil, sediment, food matrices, biological tissues. Stating the units as mass per mass keeps the value unambiguous, where ppb alone might be misread as a volume or mole ratio.
What instruments operate at ng/g levels?
ICP-MS for trace metals, GC-MS/MS for volatile and semi-volatile organics, and LC-MS/MS for polar organics all routinely quantify analytes at ng/g levels in solid matrices. Sample digestion or extraction precedes the instrumental quantification.