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Calcimator

Biological Monitoring Calculator

Compare biological specimen results (blood or urine) against ACGIH Biological Exposure Indices (BEIs) with creatinine correction for urine samples.

Inputs

Results

BEI ratio

0.42

Corrected concentration20.83
Creatinine valid? (1/0)1
Action code (0-3)0
Trend vs prior (%)0%
Exceeds BEI?0
Geometric Mean25
How to Use This Calculator
  1. Enter Measured value (µg/L or µg/dL), BEI reference value, and Urine creatinine (g/L).
  2. Set Specimen type (1=Urine, 0=Blood), Workers in group, and Prior result (µg/L).
  3. Review the BEI ratio result.
  4. Use Corrected concentration and Creatinine valid? (1/0) to inform your decision.

What each input means

Measured value (µg/L or µg/dL)
Laboratory result for the biomarker (µg/L for urine, µg/dL for blood).
BEI reference value
ACGIH Biological Exposure Index for the substance (same units as measured value).
Urine creatinine (g/L)
Creatinine concentration in g/L for urine dilution correction. Acceptable range: 0.3–3.0 g/L.
Specimen type (1=Urine, 0=Blood)
1 for urine specimen (applies creatinine correction), 0 for blood specimen.
Workers in group
Number of workers monitored (for group assessment context).
Prior result (µg/L)
Previous measurement for trend analysis (0 if none).

What each result means

BEI ratio
Ratio of measured (corrected) value to BEI. Values > 1.0 exceed the BEI.
Corrected concentration
Creatinine-corrected concentration for urine; raw value for blood.
Creatinine valid? (1/0)
1 if creatinine is in the acceptable 0.3-3.0 g/L range, 0 if sample may be unreliable.
Action code (0-3)
0=well controlled, 1=acceptable, 2=investigate, 3=overexposure.
Trend vs prior (%)
Percentage change from the prior measurement.
Exceeds BEI?
1 if the BEI ratio is ≥ 1.0, indicating exposure above the biological index.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Measured value (µg/L or µg/dL) = 25, BEI reference value = 50, Urine creatinine (g/L) = 1.2, Specimen type (1=Urine, 0=Blood) = 1 = 6 input(s) provided
  2. Calculate BEI ratio
    0.417 = 0.417
  3. Calculate Corrected concentration
    20.83 = 20.83
  4. Calculate Creatinine valid?
    Creatinine valid?
    1 = 1

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