Canadian Environmental Effects Monitoring: Experiences with Pulp and Paper and Metal Mining Regulatory Programs

In Canada, Environmental Effects Monitoring (EEM) programs exist within two regulations: the Pulp and Paper Effluent Regulations and the newMetal Mining Effluent Regulations under the Canadian Fisheries Act. EEM provides a biological, effects-based feedback loop to assess the effectiveness of technology-based regulations in protecting receiving environments. The promulgation of the Pulp and Paper Effluent Regulations, in 1992, represented a significant step forward in the Canadian regulatory approach by incorporating directly into a regulation a requirement to assess the effects of effluent discharges on receiving environments using proven scientific monitoring methodologies. Similarly, an assessment of the aquatic impacts of mines resulted in recommendations to amend the Metal Mining Effluent Regulations, recently promulgated in 2002, and includes an EEM program as a science-based feedback loop. As such, these regulations recognize the possibility that national, technology-based standards may not necessarily protect all receiving environments because of the diversity and variability of both discharges and receiving sites across the country. Since that time, EEM has improved its flexibility by considering both advances in science and the uniqueness of monitoring sites across Canada to allow the most appropriate and cost-effective monitoring approaches at each site while maintaining national consistency. This paper discusses the use of monitoring under two Canadian regulations to assess effects on aquatic ecosystems. As well, the National EEM approach to maintaining up-to-date scientific practices in a national regulatory program is discussed using examples.     

Evaluation of a guild approach to habitat assessment for forest-dwelling birds

The applicability of the Habitat Evaluation Procedure (HEP) was assessed for several nongame bird species in the central Adirondack Mountains of New York. Measures for 24 avian species and 33 associated habitat variables were collected during the summers of 1985 and 1986. The accuracy of four published Habitat Suitability Index (HSI) models was examined: pileated and downy woodpeckers, black-capped chickadee, and veery. Chickadee and veery models were judged successful and were then used to predict habitat quality for respective avian foragingguild members. The HSI model/guild approach provided poor predictors of habitat quality for ubiquitous and uncommon species. Information on relative abundance within the geographic region and specific cover types must be included when designing habitat evaluations using the guild approach.     

Fire ant thermal preferences: behavioral control of growth and metabolism

Summary Thermal preferences of well-fed and food-limited fire ant colonies (Solenopsis invicta) were studied in relation to colony growth and metabolic costs. The growth curve for well-fed colonies was strongly skewed toward warmer temperatures with maximal growth occurring near 32° C (Fig. 2A). The growth curve for food-limited colonies was skewed toward cooler temperatures with maximal colony size occurring around 25° C (Fig. 2B). Food-limited colonies apparently grew larger at cooler temperatures because metabolic costs of workers were reduced. A series of binary choice tests confirmed three predictions concerning fire ant thermal preferences (Figs. 3–4). First, well-fed colonies preferred brood temperatures very near the optimum for colony growth (31° C versus 32° C). Colonies were also able to select appropriate suboptimal growth temperatures when the optimal range was unavailable. Secondly, as predicted, a large percentage of colony workers ( 30% in well-fed colonies) consistently chose cooler temperatures than those selected for the brood. This strategy probably increases longevity of workers not directly associated with brood care. Thirdly, food-limited colonies preferred cooler temperatures than well-fed colonies. Metabolic costs of food-limited colonies were reduced by approximately 7% because of (1) slightly cooler brood temperatures (30° C versus 31° C) and because (2) an additional 20–30% of the workers selected cooler temperatures. The addition of excess food reversed food-limited thermal preferences within 12 h for the brood (Fig. 5) and several days for the workers. Contrary to expectations, thermal preferences for brood in food-limited colonies did not match the food-limited growth curve, perhaps because fire ant colonies can choose to rear brood at warm temperatures while maintaining accumulated colony biomass at cooler temperatures. Correspondence to: S.D. Porter     

Dioxin-like compounds in Australian sewage sludge--review and national survey

An Australian survey of dioxin-like compounds in sewage sludge was conducted in two parts (a) a national survey, and (b) a time-study. All sewage sludge samples analysed as part of these studies had low overall concentrations of dioxin-like compounds. Out of 37 samples, all except one, were within the reported concentration range of soil within the Australian environment. The mean concentration of dioxin-like compounds in the Australian sewage sludge survey of 2006 was found to be 5.6 (s.d. 4.5) ng WHO(05) TEQkg(-1) (n=14) and were within the range of 1.2-15.3 ng WHO(05) TEQ kg(-1). All the Australian sewage sludge samples cited in these studies were below the Victorian EPA "investigation limit" of 50 ng WHO(98) TEQ kg(-1), and well below the European proposed guidelines of 100 ng I-TEQ kg(-1). The burden of dioxin-like compounds in Australian sewage sludge is low and its land application as biosolids is not likely to pose a problem. A general positive relationship was found between population of the town producing the waste and both dioxin-like PCDD/Fs and dioxin-like PCBs. The one exception to this trend was sludge from a town that had a history of smelting and had a relatively high burden of dioxin-like compounds. Sludge from one rural WWTP also had a higher burden of dioxin-like compounds. The treatment plant services a geographically isolated town with a low population and no known emitters of dioxin-like compounds. However, this sample also had a relatively high burden of dioxin-like PCBs, which could be the source of the dioxin-like PCDD/Fs found in this sludge. The time study analyzing sludges from three WWTP from the same city between the years 2002 and 2006 found no apparent difference between WWTPs, but a statistically significant decline of 1.49 ng WHO(05) TEQ kg(-1) per year. Also, a comprehensive review of the scientific literature, presents typical levels and sources of dioxin-like compounds in international sewage sludges.     

Influence of fipronil compounds and rice-cultivation land-use intensity on macroinvertebrate communities in streams of southwestern Louisiana, USA

Laboratory tests of fipronil and its degradation products have revealed acute lethal toxicity at very low concentrations (LC50) of <0.5 microg/L to selected aquatic macroinvertebrates. In streams draining basins with intensive rice cultivation in southwestern Louisiana, USA, concentrations of fipronil compounds were an order of magnitude larger than the LC50. The abundance (rho=-0.64; p=0.015) and taxa richness (r2=0.515, p<0.005) of macroinvertebrate communities declined significantly with increases in concentrations of fipronil compounds and rice-cultivation land-use intensity. Macroinvertebrate community tolerance scores increased linearly (r2=0.442, p<0.005) with increases in the percentage of rice cultivation in the basins, indicating increasingly degraded stream conditions. Similarly, macroinvertebrate community-tolerance scores increased rapidly as fipronil concentrations approached about 1 microg/L. Pesticide toxicity index determinations indicated that aquatic macroinvertebrates respond to a gradient of fipronil compounds in water although stream size and habitat cannot be ruled out as contributing influences.     

In-car cell phone use and hazards following hands free legislation

OBJECTIVE: A new law took effect in Finland at the beginning of 2003 which prohibits the handheld use of mobile phones while driving a motor vehicle. The purpose of this study was to assess the impact of the law on phone usage and self-reported safety during the first few months and 16 months later to determine whether the initial level of compliance with the law had been sustained. METHODS: Data were collected by Gallup home poll before (spring 2002) and after legislation took effect (spring 2003 and 2004). A representative sample of drivers who owned a cell phone (n = 836 to 966) was interviewed each time. On-road observations were also collected in four cities for 2003 and 2004. RESULTS: Just after the law, 97% of drivers were aware of the new hands free legislation. In sharp contrast to the pre-law rate of 16%, 43% reported not using the phone while driving immediately after the law and 41% one year later. The occasional users especially reduced their use of phones while driving. The law was correlated to reductions in self-reported handheld use of cell phones while driving, from 55.6% pre-law to 15.2% immediately after passage. In spite of this change, however, the hands free legislation did not reduce self-reported involvement of Finnish drivers in phone-related hazards. Handheld usage was still lower in 2004 than pre-law (20.0%), but the 32% increase from 2003 was significant. Observational data collected in Finland in 2003 and 2004 showed an even higher upward trend in handheld use (87% increase, from 3.1% to 5.8%; pre-law data were not available), and matched a similar increase reported by McCartt and Geary (2004) in their observational evaluation of New York's handheld mobile phone law. CONCLUSION: The self-reports indicate that the hands-free law reduced handheld phone use, among occasional users especially, but did not reduce phone-related hazards. The effect of the law on phone use substantially declined within one year.     

Sorption equilibria of metal ions on bone char

The ability of bone char to adsorb three metal ions, namely, copper(II), zinc(II) and cadmium(II) ions from wastewater has been studied. Three single-component equilibrium systems and three binary equilibrium systems have been measured experimentally. The three single-component equilibrium data were analyzed using the Langmuir and the Sips equilibrium isotherm equations. The Sips isotherm gave a better fit of the experimental data than the Langmuir isotherm based on the sum of squares errors (SSE) analysis. The Cu-Zn, Cu-Cd and Cd-Zn binary equilibrium experimental data were examined by incorporating the Langmuir and the Sips isotherm equations into the ideal adsorbed solution theory (IAST). The solution methods and the predicted results for the three binary systems at different metal ion compositions have been evaluated. In addition, the application of the IAST to the model prediction for the fixed bed system is presented.