Partnerships and governance at the environment–health nexus in Ontario: lessons from five case examples

The move towards partnerships and collaborative governance models has been advocated in global health discussions for many years now. A case example methodology was applied to this study. It was composed of a document review and semi-structured interviews with key informants from five environment and public health partnerships in the province of Ontario, Canada. These case examples highlight the merits and the challenges of diverse partnerships, and the importance of governance and leadership models, scaling up (and out) impact, and cross-cultural communications to these arrangements. Further work is required to articulate situations in which public health partnerships can be strengthened.     

Droplet size spectra and deposits of Bacillus thuringiensis aerial sprays,following application at two volume rates over an oak forest

Abstract

Dipel® 8AF, a commercial formulation of Bacillus thuringiensis (B.t.) was sprayed undiluted at 30 BIU in 1.8L/ha over a block B1, and sprayed after dilution with water at 30 BIU in 6.2 L/ha over another block B2 in an oak forest infested with the gypsy moth (Lymantria dispar L.) in southeastern Ontario, Canada. Spray was applied in May 1987 using a Cessna 188 Agtruck aircraft equipped with four Hicronair^® AU4000 atomizers. Droplet sizes were measured at mid‐canopy level of oak trees and at ground level using cylindrical Kromekote® cards. Deposit per unit area was assessed on aluminum oak leaves.

At the lower volume rate of 1.8 L/ha, spray droplets were smaller and droplets/cm² were lower on the cylindrical Kromekote cards in B1 than those obtained in B2 which received the higher volume rate of 6.2 L/ha. The average deposit per unit area of the aluminum oak leaves, expressed in nL of the spray volume per cm² surface area, was also correspondingly lower in B1 than in B2. This was attributed to the higher volume rate of spray application used in B2 than in B1, which resulted in larger droplets and a greater volume deposit/cm² in B2.     

A fluorometric method to determine rainfastness,volatilization and photostability of glyphosate from glass slides,after application of vision® with two adjuvants

Abstract

A fluorometric method was developed to quantify glyphosate loss from glass surfaces after exposure to the natural forest environment. The method was based on the principle of converting glyphosate into glycine, followed by the fluorogenic labeling with o‐phthalaldehyde. A fluorometer (with λ _Ex = 360 nm / λ_Em =430 nm) was used to quantify the derivatized fluorogenic compound. Response was linear over the concentration range of 143, 286, 572, 858 and 1144 μg of glyphosate (acid equivalent, AE) per mL of the diluted Vision® formulation. Three end‐use mixtures of Vision® were prepared, each at a concentration of 28.6 g AE/L, without and with two adjuvants, Ethomeen® T/25 at 4.5 mL/L and Silwet^® L‐77 at 1.5 mL/L. Several dilutions of the end‐use mixtures were applied on glass slides without and with the coating of cuticular wax extracted from trembling aspen foliage. The slides were left for 5 days in a forest opening to determine rainfastness, volatilization and photostability of glyphosate. The residues were quantified using the method developed. Three calibration curves were required because Silwet decreased the fluorometric response of glyphosate, whereas Ethomeen increased it. The minimum detection limit was 143 μg of glyphosate/mL. Glyphosate was resistant to volatilization and sunlight‐mediated degradation, regardless of the presence of wax coating or the adjuvants. About 64% of the applied glyphosate was washed off after a 9.6 mm rainfall when no adjuvant was present. Both adjuvants provided some amount of rain‐protection to glyphosate, but Silwet reduced the washoff to a greater extent (46%) than Ethomeen (55%).     

Online update of model state and parameters of a Monte Carlo atmospheric dispersion model by using ensemble Kalman filter

For an atmospheric dispersion model designed for the assessment of nuclear accident consequences, some uncertain model parameters, such as source term and weather conditions, may influence the reliability of model predictions. In this respect, good estimations of both model state and uncertain parameters are required. In this paper, an ensemble Kalman filter (EnKF) based method for simultaneous state and parameter estimation, using off-site radiation monitoring data, is presented. This method is based on a stochastic state space model, which resembles the parameter errors with stochastic quantities. Three imperfect parameters, including the source release rate, wind direction and turbulence intensity were perturbed simultaneously, and multiple parameter estimation were performed. Having been tested against both simulated and real radiation monitoring data, the method was found to be able to realistically reconstruct the real scene of dispersion, as well as the uncertain parameters. The estimated parameters given by EnKF nicely converge to the true values, and the method also tracks the temporal variation of those parameters.     

Fluorinated alkyl compounds including long chain carboxylic acids in wild bird livers from Japan

A wide range of fluorinated alkyl compounds (FACs) has been reported in wildlife in various locations in the world. However, such information regarding Japanese wildlife is rarely found. In the present study, we investigated the occurrence of 21 FACs, including perfluorinated alkyl sulfonates (PFASs), perfluorinated carboxylates (PFCAs), and fluorotelomer acids, in the livers of 10 wild bird species from two regions in northern Japan. To avoid interferences, FACs were quantified by a recently developed method using acetonitrile and solid-phase extraction followed by an ion exchange HPLC column separation. Apart from perfluorooctane sulfonate (PFOS), which was found at the highest levels of all the compounds detected, several long chain perfluorinated carboxylates (PFCAs) from C8 to C16, particularly perfluorotetradecanoic acid (PFTeDA) and perfluorohexadecanoic acid (PFHxDA), were detected for the first time. Additionally, 7:3 FTCA, a fluorotelomer acid, was also detected in most swan livers from Miyagi prefecture and all the birds from Tochigi prefecture. However, none of the sulfonamides and unsaturated telomer acids were detected in any species. Swans seem to be the least exposed wild birds to FACs among the investigated birds, signifying that feeding habits may reflect FAC accumulation in wild birds. The highest total concentration of detected FACs was 405 ng g⁻¹ wet wt., which was found in a Japanese sparrowhawk, indicating that the top predatory wild birds can accumulate several long chain carboxylic acids. However, the current FAC concentrations found in livers may suggest that these compounds alone would not cause a severe toxic effect in these species.     

Chronic toxicity of tributyltin to development and reproduction of the European freshwater snail Lymnaea stagnalis (L.)

Chronic toxicity, growth and reproduction were measured in the freshwater gastropod Lymnaea stagnalis exposed to waterborne bis(tri-n-butyltin) oxide (TBTO) over a range of four nominal concentrations (0-10microg TBTl(-1)). Egg development was completely inhibited at 10microg TBTl(-1), whilst abnormal embryonic development was observed at 1microg TBTl(-1). For the solvent control and the 0.01microg TBTl(-1)treatment group, normal development of L. stagnalis was observed. Survivorship of hatchlings was significantly reduced by TBT at 1microgl(-1) while inhibition of shell growth of L. stagnalis was also observed at this concentration. The data were used to determine intrinsic growth rates (r) using two theoretical approaches (the Euler-Lotka equation and a Leslie Matrix). Both approaches showed that survival, fecundity and population growth rate were reduced at 1microg TBTl(-1). Interestingly, at 0.01microg TBTl(-1) snails showed a higher fecundity and growth rate than in the solvent control. The TBT concentration at which the r would equal zero (ECr(0)) and the population NOEC (No Observed Effect Concentration) were estimated. The population NOEC was defined as either the lower 95% confidence or lower 95% pointwise percentile limit of the ECr(0). Values obtained using the two different approaches were similar and thus a geometric mean was calculated to obtain a final representative population NOEC value for L. stagnalis of 2745ng TBTl(-1). The present data together with chronic toxicity TBT data for freshwater organisms, obtained from peer-reviewed literature, were used to construct a species sensitivity distribution (SSD). A predicted no effect concentration was then derived from the SSD (hazardous concentration at 5%, i.e., HC5 or 95% protection level). This SSD was compared with the SSD derived from saltwater species datasets. The HC5 value for saltwater species (3.55ng TBTl(-1); lower confidence limit: 1.93ng TBTl(-1)) was significantly lower than that for freshwater species (30.13ng TBTl(-1); lower confidence limit: 9.23ng TBTl(-1)), indicating that saltwater species are probably more susceptible to TBT than their freshwater counterparts.     

Gaseous and particulate polycyclic aromatic hydrocarbons (PAHs) emissions from commercial restaurants in Hong Kong

Commercial cooking emissions are important air pollution sources in a heavily urbanized city. Exhaust samples were collected in six representative commercial kitchens including Chinese restaurants, Western restaurants, and Western fast-food restaurants in Hong Kong during peak lunch hours. Both gaseous and particulate emissions were evaluated. Eight gaseous and twenty-two particulate polycyclic aromatic hydrocarbons (PAHs) were quantified in this study. In the gaseous phase, naphthalene (67-89%) was the most abundant PAH in all of the exhaust samples. The contribution of acenaphthylene in the gaseous phase was significantly higher in emissions from the Chinese restaurants, whereas fluorene was higher in emissions from the Western cooking style restaurants (i.e., Western restaurants and Western fast-food restaurants). Pyrene is the most abundant particulate PAH in the Chinese restaurants (14-49%) while its contribution was much lower in the Western cooking style restaurants (10-22%). Controlled cooking conditions were monitored in a staff canteen to compare the emissions from several different local cooking styles, including deep frying, steaming, and mixed cooking styles (combination of steaming and frying). Deep frying produced the highest amount of total gaseous PAHs, 6 times higher than the steaming. However, steaming produced the highest particulate emissions. The estimated annual gaseous PAH emissions for the Chinese restaurants, Western restaurants, and Western fast-food restaurants were 255, 173, and 20.2 t y(-1) whereas 252, 1.9, and 0.4 t y(-1) were estimated for particulate phase PAH emissions. The study provides useful information and estimates for PAH emissions from commercial cooking exhaust in Hong Kong.     

Survival strategies of plants associated with arbuscular mycorrhizal fungi on toxic mine tailings

A field survey of metal concentrations and arbuscular mycorrhizal (AM) components of plants growing on five mining sites was conducted in Chenzhou City, Hunan Province, Southern China and a control site in Hong Kong. Significant differences were observed in the average concentrations of total heavy metals (Pb, Zn, Cu, Cd) and one metalloid (As) in contaminated soils compared with the control site. Gramineae and Compositae were the dominant plant families growing on mine tailings, with Chrysanthemum moritolium (common chrysanthemum), Cynodon dactylon (Bermuda grass), Miscanthus florodulus (Sword grass) and Pteris vittata (Ladder brake fern) commonly found at all sites. AM fungal colonization was detected in most of the plants. Comparing the four common plant species, three components of mycorrhizal colonization (arbuscules, vesicles and coiled hyphae) were found in the roots of C. dactylon and P. vittata growing at Do Shun Long (DSL) mine site. Concentrations of As in fronds were 24-fold higher than in roots of P. vittata with the highest mycorrhizal colonization rate (73%) among all sampling sites. Extensive mycorrhizal colonization (85%) was also recorded in the roots of C. dactylon with As accumulation 57 times higher than in shoots. The four common plants found in metal contaminated sites had developed different strategies for survival in the contaminated sites with the aid of indigenous AM fungi.     

Analysis of multi-temporal landsat satellite images for monitoring land surface temperature of municipal solid waste disposal sites

This studypresents a remote sensing application of using time series Landsat satellite images for monitoring the Trail Road and Nepean municipal solid waste (MSW) disposal sites in Ottawa, Ontario, Canada. Currently, the Trail Road landfill is in operation; however, during the 1960s and 1980s, the city relied heavily on the Nepean landfill. More than 400 Landsat satellite images were acquired from the US Geological Survey (USGS) data archive between 1984 and 2011. Atmospheric correction was conducted on the Landsat images in order to derive the landfill sites’ land surface temperature (LST). The findings unveil that the average LST of the landfill was always higher than the immediate surrounding vegetation and air temperature by 4 to 10 °C and 5 to 11.5 °C, respectively. During the summer, higher differences of LST between the landfill and its immediate surrounding vegetation were apparent, while minima were mostly found in fall. Furthermore, there was no significant temperature difference between the Nepean landfill (closed) and the Trail Road landfill (active) from 1984 to 2007. Nevertheless, the LST of the Trail Road landfill was much higher than the Nepean by 15 to 20 °C after 2007. This is mainly due to the construction and dumping activities (which were found to be active within the past few years) associated with the expansion of the Trail Road landfill. The study demonstrates that the use of the Landsat data archive can provide additional and viable information for the aid of MSW disposal site monitoring.     

Exposure to polybrominated diphenyl ethers associated with consumption of marine and freshwater fish in Hong Kong

Concentrations of polybrominated diphenyl ethers (PBDEs) in market fish have not previously been reported in Hong Kong. Axial and ventral muscles from 10 each common species of freshwater and marine fish purchased from markets in Hong Kong were analyzed for 22 PBDEs. Among the 10 freshwater fish species, spotted snakehead (Channa maculate) contained the highest level of PBDEs in ventral muscle (130 ng g(-1) wet wt.). For marine fish, bigeye (Priacanthus macracanthus) showed significantly higher levels of PBDEs (60.7 ng g(-1)wet wt. in ventral tissue) than all other marine species. The levels of PBDEs in fish samples ranged from 0.53 to 130 ng g(-1)wetwt. The tetrabrominated congener BDE-47 and pentabrominated BDE-99 were the predominant congeners, which accounted for 27% and 30%, respectively, of the total PBDEs. Daily PBDE intake was calculated according to the different fish consumption rate for Hong Kong consumers, and the results ranged from 222 to 1198 ng day(-1) for marine fish and 403-2170 ng day(-1) for freshwater fish. The daily PBDE intake from fish reported here were higher than those reported from the United States (8.94-15.7 ng day(-1)) and Europe (14-23.1 ng day(-1)).