Using Maximum Cumulative Ratio to Assess Cumulative Risk from Chemical Exposures
Author Information
Author(s): Price Paul S., Han Xianglu
Primary Institution: The Dow Chemical Company
Hypothesis
The study proposes the Maximum Cumulative Ratio (MCR) as a tool to evaluate when cumulative risk assessments are necessary for chemical exposures.
Conclusion
The MCR can help identify the need for cumulative risk assessments and quantify the toxicity missed when such assessments are not performed.
Supporting Evidence
- MCR values suggest that cumulative toxicity is often dominated by one or two chemicals.
- 98% of samples had Hazard Indices (HI) less than one, indicating low cumulative risk.
- Non-detects significantly impacted estimates of MCR and HI for samples with low cumulative toxicity.
- Correlation between HI and the number of detected chemicals was strong, while MCR showed weak correlation.
- Performing cumulative risk assessments may not significantly change risk predictions for more toxic mixtures.
Takeaway
This study shows a way to figure out if we need to check for risks from many chemicals together, instead of just one at a time.
Methodology
The study analyzed surface water samples for multiple chemicals and calculated MCR values based on cumulative toxicity assessments.
Potential Biases
Non-detects in the data could influence the estimates of cumulative toxicity.
Limitations
The study's findings may not reflect current practices as the data is from samples taken over a decade ago.
Participant Demographics
The study analyzed samples from various locations across the U.S. without specific demographic details.
Statistical Information
P-Value
p<0.0001
Statistical Significance
p<0.0001
Digital Object Identifier (DOI)
Want to read the original?
Access the complete publication on the publisher's website