Examining hydraulic fracturing chemicals: A temporal and comparative analysis.

Area of Science:

• Environmental Science
• Public Health
• Chemical Safety

Background:

• Hydraulic fracturing (HF) is a key global energy policy issue.
• Understanding risks of HF chemicals to drinking water is crucial.
• Limited and variable disclosure of HF chemicals hinders research.

Purpose of the Study:

• To develop a repeatable method for processing HF chemical disclosure data.
• To analyze HF chemical trends from 2014-2020 using US FracFocus data.
• To compare HF chemicals with those in drinking water, food, and cosmetics.

Main Methods:

• Utilized US FracFocus data from 2014-2020.
• Identified and quantified unique hydraulic fracturing chemicals.
• Cross-referenced identified chemicals with reference lists of common exposure chemicals.

Main Results:

• 1,244 unique hydraulic fracturing chemicals were identified.
• Annual unique chemical counts decreased by 32.3% (878 to 594).
• 69.7% of identified HF chemicals are also found in drinking water, food, or cosmetic reference lists.

Conclusions:

• The hydraulic fracturing chemical landscape is dynamic, trending towards fewer and generally safer disclosed chemicals.
• Increased data quality and transparency were observed.
• Significant overlap exists between HF chemicals and those with known human contact, warranting further risk assessment.