Relationships between benthic macroinvertebrate community structure and geospatial habitat, in‐stream water chemistry, and surfactants in the effluent‐dominated Trinity River, Texas, USA

Abstract

Over the past 20 years, benthic macroinvertebrate community structure studies have been conducted on the upper Trinity River, Texas, USA, which is dominated by municipal wastewater treatment plant (WWTP) and industrial effluents. The Trinity River is located in the Dallas-Fort Worth metropolitan area, and is the most highly populated and industrialized watershed in Texas. As such, the Trinity River represents a near-worst-case scenario to examine the environmental effects of domestic-municipal and industrial effluents on aquatic life. A 1987 to 1988 study concluded that many stretches of the river supported a diverse benthic community structure; however, a decline in taxa richness occurred immediately downstream of WWTPs. A 2005 study designed to parallel the 1987 to 1988 efforts evaluated how changes in water quality, habitat, and increased urbanization impacted benthic community structure. Physicochemical measurements, habitat quality, geospatial variables, and benthic macroinvertebrates were collected from 10 sites. Surfactants were measured and toxic units (TUs) were calculated for surface water and pore water as indicators of domestic/household use of cleaning products. Total TUs indicated a low potential for biological impacts. Toxic unit distribution was not dependent on WWTP location and did not correlate with any benthic variable. Eight environmental parameters were determined to be useful for predicting changes in benthic macroinvertebrate community structure: surfactant surface water TUs (SWTU), in-stream habitat cover, and surface water total organic carbon were the top three parameters. Abundance, taxa richness, and taxa similarity in 2005 had increased since the earlier study throughout the immediate vicinity of the metropolitan area.

Environmental Safety of the Use of Major Surfactant Classes in North America

“…For example, in Sanderson et al (2006a, 2006b), Atkinson et al (2009) and Slye et al (2011) studies, the monitoring sites were chosen based on the following criteria: (1) typical treatment efficiency (i.e., activated sludge); (2) wastewater influent that receives less than 10% industrial contributions; (3) low dilution (i.e., 7Q10 flow yielding dilution factors between 1 and 3) and (4) accessibility for sampling water, sediment, and biota. The presence of industrial contributions to domestic wastewater can both provide potential confounding chemical influences to wastewater treatment efficiencies as well as dilute the domestic sources of surfactants.…”

“…EPA, 1999) was used. For the Trinity River studies by Atkinson et al (2009) and Slye et al (2011), the Habitat Quality Index Score method was used (Texas Commission of Environmental Quality, 1999). Adequate habitat quality for fish and macroinvertebrates is essential for assessing the potential effects of chemicals.…”

“…The subsequent paragraphs represent a synthesis of several surfactant monitoring studies, including Sanderson et al (2006a, 2006b), Atkinson et al (2009), and Slye et al (2011).…”

“…Atkinson et al (2009) and Slye et al (2011) conducted a retrospective risk assessment study on the Trinity River in Texas. The Trinity River system has been extensively studied.…”

Use of Market Forensics to Estimate the Environmental Load of Ingredients from Consumer Products

“…While environmental risk assessments of these materials have predicted that there is low risk from their use in consumer products (Atkinson et al, 2009;Slye et al, 2011), it has been recognized that these conclusions are confounded by the presence of naturally occurring alcohols in the environment . Apportioning risk between anthropogenic sources and natural sources has been a difficult task in the past.…”