Calculator Inputs
The page uses a single-column structure overall. Only the calculator fields use a responsive grid: three columns on large screens, two on medium screens, and one on mobile.
Formula Used
Water absorbed lead (μg/day) = Water concentration × Water intake × Water bioaccessibility
Air absorbed lead (μg/day) = Air concentration × Inhalation rate × Respiratory uptake
Soil or dust absorbed lead (μg/day) = (Soil concentration × Soil ingestion ÷ 1000) × Soil bioaccessibility
Food absorbed lead (μg/day) = Food concentration × Food intake × Food bioaccessibility
Paint absorbed lead (μg/day) = (Paint concentration × Paint ingestion ÷ 1000) × Paint bioaccessibility
Total absorbed lead (μg/day) = Water + Air + Soil/Dust + Food + Paint
Weekly burden (μg/week) = Total absorbed lead × Exposure days per week
Average daily dose (μg/kg/day) = (Weekly burden ÷ 7) ÷ Body weight
Screening ratio = Average daily dose ÷ Custom screening benchmark
Cumulative absorbed lead (mg) = Weekly burden × 52 × Duration ÷ 1000
How to Use This Calculator
- Enter body weight, weekly exposure frequency, duration, and your chosen screening benchmark.
- Fill in pathway concentrations for water, air, soil or dust, food, and paint.
- Enter contact or ingestion rates for each pathway in the stated units.
- Adjust bioaccessibility percentages to reflect expected absorption behavior.
- Click Calculate Exposure to display results above the form.
- Review pathway shares, dose-normalized metrics, and cumulative totals.
- Use the CSV or PDF buttons to save the calculated summary.
Example Data Table
| Example Parameter | Example Value | Unit |
|---|---|---|
| Body weight | 70 | kg |
| Exposure days | 5 | days/week |
| Water lead concentration | 8 | μg/L |
| Water intake | 2.2 | L/day |
| Air lead concentration | 0.20 | μg/m³ |
| Inhalation rate | 16 | m³/day |
| Soil lead concentration | 180 | mg/kg |
| Soil ingestion | 40 | mg/day |
| Food lead concentration | 5 | μg/kg |
| Food intake | 1.4 | kg/day |
| Paint lead concentration | 900 | mg/kg |
| Paint ingestion | 5 | mg/day |
| Illustrative total absorbed lead | 14.605 | μg/day |
| Illustrative weekly burden | 73.025 | μg/week |
| Illustrative average daily dose | 0.1490 | μg/kg/day |
Frequently Asked Questions
1. What does this calculator estimate?
It estimates absorbed lead from water, air, soil or dust, food, and paint pathways. It then summarizes daily intake, weekly burden, body-weight-normalized dose, screening ratio, and cumulative absorbed mass over the chosen duration.
2. Why are bioaccessibility percentages included?
Lead present in a material is not always fully absorbed by the body. Bioaccessibility factors let you model partial uptake, making the estimate more flexible than using raw concentration values alone.
3. Why do some pathways use mg/kg and others use μg/L or μg/kg?
Different media are commonly reported in different units. Water and air often use concentration per volume, while soil and paint commonly use mass per mass. The calculator converts these into absorbed micrograms per day.
4. What is the screening ratio?
The screening ratio compares the calculated average daily dose with your selected benchmark dose. A higher ratio means the modeled exposure is larger relative to that chosen screening target.
5. Is this a medical diagnosis tool?
No. It is an educational and screening calculator. It does not diagnose poisoning, replace laboratory testing, or substitute for advice from qualified environmental health, industrial hygiene, or medical professionals.
6. How should I choose the benchmark dose?
Use a benchmark that matches your project, internal policy, or technical review method. Because different organizations use different screening conventions, the field is intentionally user-defined.
7. Can I use only one or two pathways?
Yes. Leave any unused pathway values at zero. The calculator will still total only the active routes and show their percentage contribution in the results table and chart.
8. What is the benefit of the chart?
The Plotly graph quickly highlights which pathway contributes the most absorbed lead. That makes it easier to prioritize mitigation steps, compare scenarios, and present results in reviews or audits.