Aquatic hazard assessment of MON 0818, a commercial mixture of alkylamine ethoxylates commonly used in glyphosate-containing herbicide formulations. Part 1: Species sensitivity distribution from laboratory acute exposures

Environ Toxicol Chem. 2017 Feb;36(2):501-511. doi: 10.1002/etc.3559. Epub 2016 Aug 30.

Abstract

The sensitivity of 15 aquatic species, including primary producers, benthic invertebrates, cladocerans, mollusks, and fish, to MON 0818, a commercial surfactant mixture of polyoxyethylene tallow amines, was evaluated in standard acute (48-96-h) laboratory tests. In addition, the potential for chronic toxicity (8 d) was evaluated with Ceriodaphnia dubia. Exposure concentrations were confirmed. No significant effects on any endpoint were observed in the chronic test. A tier-1 hazard assessment was conducted by comparing species sensitivity distributions based on the generated data, as well as literature data, with 4 exposure scenarios. This assessment showed moderate levels of hazard (43.1% of the species exposed at or above median effective concentration levels), for a chosen worst-case scenario-unintentional direct over-spray of a 15-cm-deep body of water with the maximum label application rate for the studied formulations (Roundup Original, Vision Forestry Herbicide; 12 L formulation ha-1 , equivalent to 4.27 kg acid equivalent [a.e.] ha-1 ). The hazard decreased to impairment of 20.9% of species under the maximum application rate for more typical uses (6 L formulation ha-1 , 2.14 kg a.e. ha-1 ), and down to 6.9% for a more frequently employed application rate (2.5 L formulation ha-1 , 0.89 kg a.e. ha-1 ). Finally, the percentage (3.8%) was less than the hazardous concentration for 5% of the species based on concentrations of MON 0818 calculated from maximum measured concentrations of glyphosate in the environment. Environ Toxicol Chem 2017;36:501-511. © 2016 SETAC.

Keywords: Alkylamine ethoxylates; Hazard; MON 0818; Polyoxyethylene tallow amines; Species sensitivity distribution; Toxicity.

MeSH terms

  • Animals
  • Aquatic Organisms / drug effects*
  • Fats / chemistry
  • Fats / toxicity*
  • Glycine / analogs & derivatives*
  • Glycine / chemistry
  • Glyphosate
  • Herbicides / chemistry*
  • Polyethylene Glycols / chemistry
  • Polyethylene Glycols / toxicity*
  • Risk Assessment
  • Species Specificity
  • Surface-Active Agents / chemistry
  • Surface-Active Agents / toxicity*
  • Water Pollutants, Chemical / chemistry
  • Water Pollutants, Chemical / toxicity*

Substances

  • Fats
  • Herbicides
  • MON 0818
  • Surface-Active Agents
  • Water Pollutants, Chemical
  • Polyethylene Glycols
  • Glycine