Microplastics: addressing ecological risk through lessons learned.

Plastic litter is an environmental problem of great concern. Despite the magnitude of the plastic pollution in our water bodies, only limited scientific understanding is available about the risk to the environment, particularly for microplastics. The apparent magnitude of the problem calls for quickly developing sound scientific guidance on the ecological risks of microplastics.

Decay model for biocide treatment of unballasted vessels: application for the Laurentian Great Lakes.

A biocide decay model was developed to assess the potential efficacy and environmental impacts associated with using glutaraldehyde to treat unballasted overseas vessels trading on the Laurentian Great Lakes. The results of Monte Carlo simulations indicate that effective glutaraldehyde concentrations can be maintained for the duration of a vessel's oceanic transit (approximately 9-12 days): During this transit, glutaraldehyde concentrations were predicted to decrease by approximately 10% from initial treatment levels (e.g.

Chronic toxicity of glutaraldehyde: differential sensitivity of three freshwater organisms.

The biocide, glutaraldehyde, is a potential environmental contaminant due to its widespread use in medical applications, off-shore oil extraction, and pulp mill processing. It has also been proposed as a candidate for treating the ballast water of vessels, which could result in a substantial increase in environmental release. To assess the potential for environmental impacts associated with glutaraldehyde, three standard chronic toxicity bioassays were performed: 96-h phytoplankton growth bioassays using Pseudokirchneriella subcapitata (formerly, Selenastrum capricornutum), three-brood reproduction bioassays using Ceriodaphnia dubia, and an embryo-larval bioassay using steelhead trout, Oncorhynchus mykiss.