MTBE Ambient Water Quality Criteria Development:  A Public/Private Partnership

Abstract

A public/private partnership was established in 1997, under the administrative oversight of the American Petroleum Institute (API), to develop aquatic toxicity data sufficient to calculate ambient water quality criteria for methyl tertiary-butyl ether (MTBE), a gasoline oxygenate. The MTBE Water Quality Criteria Work Group consisted of representatives from private companies, trade associations, and USEPA. Funding was provided by the private entities, while aquatic biological/toxicological expertise was provided by industry and USEPA scientists. This public/private partnership constituted a nonadversarial, cost-effective, and efficient process for generating the toxicity data necessary for deriving freshwater and marine ambient water quality criteria. Existing aquatic toxicity data were evaluated for acceptability, consistent with USEPA guidance, and nineteen freshwater and marine tests were conducted by commercial laboratories as part of this effort to satisfy the federal criteria database requirements. Definitive test data were developed and reported under the oversight of industry study monitors and Good Laboratory Practice standards auditors, and with USEPA scientists participating in advisory and critical review roles. Calculated, preliminary freshwater criteria for acute (Criterion Maximum Concentration) and chronic (Criterion Continuous Concentration) exposure effect protection are 151 and 51 mg MTBE/L, respectively. Calculated, preliminary marine criteria for acute and chronic exposure effect protection are 53 and 18 mg MTBE/L, respectively. These criteria values may be used for surface water quality management purposes, and they indicate that ambient MTBE concentrations documented in U. S. surface waters to date do not constitute a risk to aquatic organisms.

Adsorption of methyl tert-butyl ether (MTBE) onto ZSM-5 zeolite: Fixed-bed column tests, breakthrough curve modelling and regeneration

“…In spite of the bans in some countries, it is still the second most common volatile organic compound in shallow groundwater (Levchuk et al, 2014). Due to its genotoxicity, its hazard of causing skin and eye irritation and its unpleasant odour (Mancini et al, 2002), the existence of MTBE in aquatic environments has raised considerable public concerns.…”

Effect of Methyl tert-Butyl Ether on the Bioconcentration and Photoinduced Toxicity of Fluoranthene in Fathead Minnow Larvae (Pimephales promelas)

“…1634-04-4), in a typical gasoline formulation, has an equilibrium water concentration of approximately 5000 mg/L at room temperature and readily partitions into aquatic systems (4). The toxicity of MTBE is low as compared to environmental exposures in both mammals and aquatic organisms (5)(6)(7)(8). Thus, it has been suggested that the risk of adverse effects because of MTBE in aquatic systems is minimal (8).…”

“…The toxicity of MTBE is low as compared to environmental exposures in both mammals and aquatic organisms (5)(6)(7)(8). Thus, it has been suggested that the risk of adverse effects because of MTBE in aquatic systems is minimal (8).…”

Using Monte Carlo analysis to characterize the uncertainty in final acute values derived from aquatic toxicity data

“…As a result, it is common for EPA WQC documents to present only deterministic values for criteria (e.g., USEPA 2009). Several peer-reviewed publications that present proposed WQC using the 1985 Guidelines also provide only deterministic values with no quantitative characterization of uncertainty (Hohreiter and Rigg 2001, Tong et al 1996, Yin et al 2003, Mancini et al 2002, Augspurger et al 2003, March et al 2007). …”