Figure 1

The GC × GC-TOFMS total ion chromatograms for fatty tissue of mussels exposed to produced water from hydraulic fracturing operations (A) control group, (B) low-dose, (C) high-dose (D) the produced water used for the dosing. The mussels exposed to produced water (panel B and C) show an increase in cyclic hydrocarbons as observed in the produced water panel (D) as highlighted in the white ovals. The produced water (D) is dominated by saturated hydrocarbons, including n-alkanes, branched alkanes, and cyclic saturated hydrocarbons.