Nonylphenol and Nonylphenol Ethoxylates in Fish, Sediment, and Water from the Kalamazoo River, Michigan K. Kannan, 1 T. L. Keith, 1 C. G. Naylor, 2 C. A. Staples, 3 S. A. Snyder, 1 J. P. Giesy 1 1 Department of Zoology, 213 National Food Safety and Toxicology Center, and Institute for Environmental Toxicology, Michigan State University, East Lansing, Michigan 48824, USA 2 Huntsman Corporation, Austin, Texas 78752, USA 3 Assessment Technologies Incorporated, Fairfax, Virginia 22030, USA Received: 18 December 2001 /Accepted: 13 May 2002 Abstract. A survey measuring concentrations of nonylphenol (NP) and its ethoxylates (NPEs) in fish was performed in the Kalamazoo River, Michigan, USA, in 1999. Of 183 fish ana- lyzed, 59% had no detectable NP or NPE. Detected concentra- tions were reported to range from 3.3 (limit of detection) to 29.1 ng NP/g wet weight. To further explore the means of exposure of NP and NPE in the fish, concentrations of NP and its mono-through tri-ethoxylates (NPE 1–3 ) were measured in fish, sediment, and water collected near two wastewater treat- ment plants on the Kalamazoo River in 2000. Samples were analyzed using exhaustive steam distillation with concurrent liquid extraction. Nonylphenol ethoxycarboxylates (NPE 1–3 C) were also analyzed in water. Concentrations of NP and NPEs in fish were less than the method detection limits (MDLs) in all the samples except one fish, which contained 3.4 ng NP/g wet weight, just above the detection limit of 3.3 ng/g. Three of 36 sediments and 1 of 24 water samples contained detectable concentrations of NP or NPE 1 . NPE 2 , NPE 3 , and NPEC were not detected in water samples. Alkylphenol ethoxylates, particularly nonylphenol ethoxylates (NPEs), are widely used nonionic surfactants. NPEs are used as detergents, emulsifiers, wetting agents, and dispersing agents in household and industrial products and in agricultural applica- tions. These compounds enter wastewater treatment plants (WWTPs) through domestic and industrial discharges. Effi- cient biological wastewater treatment processes generally re- move approximately 95% of the NPEs (Naylor 1995). In the sewage treatment process, NPEs aerobically degrade to nonyl- phenol (NP), mono- and di-ethoxylates (NPE 1–2 ) and ethoxy carboxylates (NPECs) (Figure 1). Some of the degradation products, such as NP, are more lipophilic and tend to sorb to organic surfaces. For instance, log 10 octanol-water partitioning coefficient (K ow ) of NP is in the range of 4.2 to 4.5 (McLeese et al. 1981; Ahel and Giger 1993) and hence are associated mainly with final sewage sludge. Sludge is usually applied to fields as a biosolid, incinerated, or land-filled. The remaining residues of the biological breakdown of NPE are discharged to receiving waters and are the presumed source of exposure to fish and other aquatic organisms. The occurrence of NP and NPEs in sewage treatment plant effluents (Ahel et al. 1987; Bennie et al. 1997) and in water and sediments has been documented (Naylor et al. 1992; Nimrod and Benson 1996; Maguire 1999; Snyder et al. 1999; Yamashita et al. 2000; Kannan et al. 2001). Nonylphenol ethoxycarboxylates (NPECs 1–3 ) are aerobic degradation products of NPEs formed during wastewater treatment (Ahel et al. 1987; Lee et al. 1997). Some studies have reported the occurrence of NPECs in water (Di Corcia et al. 1994; Field and Reed 1996; Lee et al. 1998). Only a few studies have examined the occurrence of NP and NPEs in fish (Lye et al. 1999; Tsuda et al. 2000; Keith et al. 2001). The first part of this study (Keith et al. 2001) reported the occurrence of NP in fish tissues collected from the Kalama- zoo River, Michigan, USA, in 1999. Of 183 fish analyzed, 41% had concentrations ranging from 3.3 to 29 ng NP/g wet weight (Keith et al. 2001). Some of the fish with detectable concen- trations of NP were collected near WWTPs in the cities of Kalamazoo and Battle Creek (Figure 2). This study was con- ducted to further examine the occurrence of NP, nonylphenol mono- through triethoxylates (NPE 1–3 ) in sediment, water, and fish tissue collected at those same sites during July–August 2000. In addition, concentrations of NPE 1–3 C were also ana- lyzed in water samples. Materials and Methods Samples Sampling on the Kalamazoo River was conducted up and downstream of the Kalamazoo and Battle Creek WWTPs in Michigan (Figure 2). The stream flow rate at the time of sampling was approximately 500 cubic feet per s. The Battle Creek WWTP employs activated sludge treatment process (secondary), and the Kalamazoo WWTP employs Correspondence to: K. Kannan; email: kuruntha@msu.edu Arch. Environ. Contam. Toxicol. 44, 77– 82 (2003) DOI: 10.1007/s00244-002-1267-3 ARCHIVES OF Environmental Contamination and T oxicology © 2003 Springer-Verlag New York Inc.