Acute and Chronic Toxicity of Sodium Nitrate and Sodium Sulfate to Several Freshwater Organisms in Water‐Only Exposures

Abstract

Elevated nitrate (NO3) and sulfate (SO4) in surface water are of global concern, and studies are needed to generate toxicity data to develop environmental guideline values for NO3 and SO4. The present study was designed to fill existing gaps in toxicity databases by determining the acute and/or chronic toxicity of NO3 (tested as NaNO3) to a unionid mussel (Lampsilis siliquoidea), a midge (Chironomus dilutus), a fish (rainbow trout, Oncorhynchus mykiss), and 2 amphibians (Hyla versicolor and Lithobates sylvaticus), and to determine the acute and/or chronic toxicity of SO4 (tested as Na2SO4) to 2 unionid mussels (L. siliquoidea and Villosa iris), an amphipod (Hyalella azteca), and 2 fish species (fathead minnow, Pimephales promelas and O. mykiss). Among the different test species, acute NO3 median effect concentrations (EC50s) ranged from 189 to >883 mg NO3‐N/L, and chronic NO3 20% effect concentrations (EC20s) based on the most sensitive endpoint ranged from 9.6 to 47 mg NO3‐N/L. The midge was the most sensitive species, and the trout was the least sensitive species in both acute and chronic NO3 exposures. Acute SO4 EC50s for the 2 mussel species (2071 and 2064 mg SO4/L) were similar to the EC50 for the amphipod (2689 mg SO4/L), whereas chronic EC20s for the 2 mussels (438 and 384 mg SO4/L) were >2‐fold lower than the EC20 of the amphipod (1111 mg SO4/L), indicating the high sensitivity of mussels in chronic SO4 exposures. However, the fathead minnow, with an EC20 of 374 mg SO4/L, was the most sensitive species in chronic SO4 exposures whereas the rainbow trout was the least sensitive species (EC20 > 3240 mg SO4/L). The high sensitivity of fathead minnow was consistent with the finding in a previous chronic Na2SO4 study. However, the EC20 values from the present study conducted in test water containing a higher potassium concentration (3 mg K/L) were >2‐fold greater than those in the previous study at a lower potassium concentration (1 mg K/L), which confirmed the influence of potassium on chronic Na2SO4 toxicity to the minnow. Environ Toxicol Chem 2020;39:1071–1085. © 2020 SETAC

Evaluation of Acute and Chronic Toxicity of Nickel and Zinc to 2 Sensitive Freshwater Benthic Invertebrates Using Refined Testing Methods

“…An irregular concentration response was also found in 3 chronic mussel tests with ammonia, chromium (VI), and KCl (Wang et al 2011a, 2017b, 2018a), although regular concentration responses were generally observed in >50 chronic mussel tests conducted at CERC with >15 organic and inorganic chemicals (e.g., Wang et al 2007, 2011b, 2018b, 2020; Besser et al 2011; Kunz et al 2017; Ivey et al 2018). Unlike commonly tested invertebrates, such as amphipods ( H. azteca ), the size variation of juvenile mussels may substantially increase over time within a batch, treatment, or replicate group in laboratory culture and long‐term toxicity testing (Barnhart et al 2006; Wang et al 2018a; Kunz et al 2020a).…”

Acute Toxicity of Sodium Chloride, Nitrates, Ortho-Phosphates, Cadmium, Arsenic and Aluminum for Juveniles of the Freshwater Pearl Mussel: Margaritifera Margaritifera (L.1758)

“…In our study, the 96 h median effective concentrations for nitrate and ortho-phosphate on 13-month old juveniles were between 1000 and 1500 mg NO 3 − /L and >5.01 mg PO 4 3− /L, respectively. We also found that 13-month-old juveniles are tolerant to very high concentrations of NO 3 − and PO for larvae midge (Chironomus dilitus) and rainbow trout juveniles (Oncorhynchus mykiss), respectively, with nitrate EC50 of 2946 mg NO 3 − /L for the unionid mussel [58]. However, these threshold values are significantly higher than the nitrate concentrations reported in the natural environment.…”

Method Development for a Short‐Term 7‐Day Toxicity Test with Unionid Mussels

“…The test water for the feeding experiments and NaCl tests was a diluted well water prepared by diluting the CERC well water (a hardness of ~300 mg/L as CaCO 3 ) with deionized water to a hardness of 100 mg/L as CaCO 3 . The diluted well water is routinely used in laboratory toxicity testing and culture with different test species, including different ages of juvenile mussels, at CERC and nominal water quality characteristics are generally as follows: hardness 100 mg/L as CaCO 3 , alkalinity 90 mg/L as CaCO 3 , pH 8.2, calcium 26 mg/L, potassium 1.0 mg/L, magnesium 9.0 mg/L, sodium 10 mg/L, chloride 11 mg/L, sulfate 20 mg/L, and dissolved organic carbon 0.5 mg/L (Wang et al, 2016(Wang et al, , 2018a(Wang et al, , 2018c(Wang et al, , 2020a(Wang et al, , 2020b. The water quality characteristics of the diluted well water are similar to those of the MHRW, except that the MHRW has higher concentrations of potassium (~3.0 mg/L) and sodium (36 mg/L), but a lower concentration of chloride (3.0 mg/L) compared with the diluted well water (Wang et al, 2016).…”

“…Unionid mussels are one of the most imperiled faunal groups in the world, and environmental pollution has been linked as a contributing factor to the decline of mussel populations (Haag, 2012; Lopes‐Lima et al, 2017; Lydeard et al, 2004; Strayer et al, 2004). Recent studies have demonstrated that mussels are among the most sensitive freshwater species to a variety of contaminants, including ammonia, some metals (e.g., aluminum, copper, nickel, and zinc), and major ions (e.g., chloride, nitrate, potassium, and sulfate; Bringolf et al, 2007; Cope et al, 2008; Gillis, 2011; Gillis et al, 2008, 2010, 2021; Miao et al, 2010; Newton & Bartsch, 2007; Salerno et al, 2020; Wang et al, 2007a, 2007b, 2010, 2011a, 2011b, 2016, 2017; 2018a, 2018b, 2018c; 2020a, 2020b). Therefore, mussels are likely susceptible to the effects of these and other toxicants from nonpoint and point sources, including effluent discharges.…”