ctxR: Utilities for interacting with the CTX APIs

Area of Science:

• Computational toxicology
• Environmental science
• Data science

Background:

• The US EPA's Center for Computational Toxicology and Exposure developed CTX APIs for accessing chemical data.
• The CompTox Chemicals Dashboard (CCD) aggregates chemical data from various sources.
• Programmatic access to toxicology data is crucial for reproducible scientific research.

Purpose of the Study:

• Introduce ctxR, an open-source R package for interacting with CTX APIs.
• Demonstrate the utility of ctxR through a case study.
• Facilitate transparent and reproducible access to toxicology and exposure data.

Main Methods:

• Developed ctxR, an R client package for CTX APIs.
• Utilized CTX APIs for data retrieval from the CompTox Chemicals Dashboard and other sources.
• Conducted a case study comparing traditional Points of Departure (PODs) with PODs derived from New Approach Methods (NAMs), termed PODNAM.

Main Results:

• The ctxR package provides seamless programmatic access to diverse toxicological datasets.
• The case study successfully compared traditional PODs and PODNAMs against external exposure estimates.
• The analysis highlighted the effectiveness of ctxR in integrating various data types for risk assessment.

Conclusions:

• ctxR enhances scientific research by enabling transparent, reproducible, and programmatic access to computational toxicology and exposure data.
• The package empowers researchers to conduct complex analyses, such as comparing different methods for deriving Points of Departure.
• ctxR facilitates a deeper understanding of chemical risks by integrating diverse data sources and analytical approaches.