Pharmaceuticals and Personal Care Products (PPCPs) and their effects on the freshwater rotifer Plationus patulus: a comparison between impacted and unimpacted populations

Pharmaceuticals and Personal Care Products (PPCPs) are chemicals of emerging concern that are present in our nation’s waterways. The Rio Grande is important to the United States and Mexico since it’s a major source of drinking and irrigation water. The river receives pollutants from industrial, urban and agricultural returns that potentially affect the aquatic ecosystem. Little is known about PPCPs in the river and less is understood about their impacts on aquatic life. A rotifer population from an urban location, El Paso, TX, (EP) and one from a remote location near Big Bend National Park, TX (BB) were tested for acute and chronic toxicity of 4 PPCPs (caffeine, acetamidophenol, triclosan, fluoxetine). 48 hr LC₅₀ tests show the BB population has higher tolerance to acetamidophenol (BB:319 mg/L; EP:121 mg/L) while LC50s for caffeine were similar (BB:423 mg/L; EP:435 mg/L). In chronic exposures, even low concentrations of acetamidophenol (10-20 mg/L) resulted in the production of unviable eggs (0% in control vs. 58% in treatments) and thus negative growth rates for both populations. GLMM analysis of chronic exposures show significant decreases in growth rates among treatments for acetamidophenol (BB: F=20.96, p<0.0001 for days 3-6 and EP: F=43.04, p<0.0001 for days 3-6), caffeine (BB: F=6.63, p<0.0185 for days 4-6 and EP: F=11.42, p<0.0001 for days 3-6), and triclosan (BB: F=10.06, p<0.0001 for days 4-6 and EP: F=29.39, p<0.0001 for days 3-6). Fluoxetine exposures are underway. Our results provide insight into how these compounds impact aquatic invertebrates and provide data to better protect aquatic ecosystems.