The Effects of Motorway Runoff on Freshwater Ecosystems: 2. Identifying Major Toxicants

Abstract

Previous studies have provided prima facie evidence that runoff from the MI motorway, UK, affects both the quality of the receiving water and the biota living there, in sites short distances from point sources-i.e., possible worst-case situations. Because discharges contain a wide variety of contaminants, both the identification of toxicants and the establishment of causal relationships between observed changes in waterhediment quality and biology are often difficult. In this particular case, the problem was addressed by conducting a series of toxicity tests using the benthic amphipod Gummnruspulex. The abundance of this species was greatly reduced downstream of the point where motorway runoff entered the stream. Stream water contaminated with motorway runoff was not toxic to G. pulex. However, exposure to contaminated sediments resulted in a slight reduction in survival over 14 d, and sediment manipulation experiments identified hydrocarbons, copper, and zinc as potential toxicants. Spiking experiments confirmed the importance of hydrocarbons, and fractionation studies indicated that most of the observed toxicity was due to the fraction containing polycyclic aromatic hydrocarbons. Animals exposed to contaminated sediments and water spiked with sediment extract accumulated aromatic hydrocarbons in direct proportion to exposure concentrations.

Sediment Quality Assessment of Road Runoff Detention Systems in Sweden and the Potential Contribution of Tire Wear

“…Effects on the benthic fauna in streams receiving highway runoff have also been somewhat inconsistent between studies; effects were shown by Shutes (1984) and by Maltby et al (1995a), whereas no effects were observed by Grapentine et al (2004), and no or only slight effects were observed by Perdikaki and Mason (1999). Smith and Kaster (1983) observed no effects on macroinvertebrates in streams receiving runoff from roads with a traffic intensity of <7,000-8,000 vehicles per day, whereas a stream receiving runoff from a road with a higher traffic intensity showed a higher abundance.…”

“…Road runoff contains a range of contaminants, such as metals and PAHs, that can cause chemical and biological alterations in receiving waters (Maltby et al 1995a, b). The contaminants originate from vehicles (e.g.…”

Impact of urbanization on the water quality, fish habitat, and fish community of a Lake Ontario marsh, Frenchman’s Bay

“…These summer decreases and winter increases in conductivity following precipitation suggest that a relatively small increase in impervious surface area in the watershed can yield heightened stream conductivity (Walsh et al 2005). Highway run-off can also contain elevated levels of such heavy metals as cadmium, copper, lead and zinc (Marsalek and Ng 1989;Gray 2004), which has been linked to degraded aquatic diversity and health (Maltby et al 1995). Heavy metal contamination in the Bay is a recent phenomenon with sediment cores showing elevated levels of heavy metals only in the upper portion of the core that date back to the 1960s (Eyles et al 2003).…”

Evaluation of the Pollutant Content in Road Runoff First Flush Waters

“…All the above cited pollutants can enter aquatic systems mainly via runoff, thus contributing to water and soil contamination (Boxall and Maltby, 1995;Maltby et al, 1995a;Maltby et al, 1995b;Perdikaki and Mason, 1999), the extent of such contamination being related to different factors, among which volume of traffic, rainfall and size of receiving waters are crucial.…”