Sand Contamination Research Articles

Mapping Heavy Metal Concentrations in Beach Sands Using GIS and Portable XRF Data

It is necessary to investigate the contamination of beach sands to ensure water safety, as they may contain potentially toxic trace elements. Tourists, oil spills, or replenishing sands can cause beach sand contamination. In this study, heavy metal contamination maps of lead (Pb) and zinc (Zn) were created for Wolpo Beach, on the eastern coast of Korea, using portable X-ray fluorescence and geographic information systems (GIS). Interpolation methods, such as kriging and inverse distance weighting, were used in this study and their results were compared. Understanding the spatial variation of potentially toxic trace elements in beach sand is necessary to determine suitable measures for preventing contamination. Sufficient sand data for understanding spatial patterns can be acquired by using rapid portable X-ray fluorescence analysis. As a result, we could create heavy metal concentration maps for the sand of Wolpo Beach. It was confirmed that the southern part of the target area is more contaminated than the northern part. However, there are no sand areas with highly concentrated heavy metal levels. In addition, no sample data exceed the soil contamination standards. This study demonstrates that portable X-ray fluorescence and geographic information systems can be utilized for investigating and preventing the contamination of beach sands by creating heavy metal concentration maps.

X-Ray Spectroscopic Quantification of Struvite and Dittmarite Recovered from Wastewater.

Phosphorus recovery from wastewater as struvite (MgNHPO⋅6HO) or dittmarite (MgNHPO⋅HO) can decrease water pollution risk, as well as produce a P-rich material suitable as fertilizer. However, most studies to date have focused on the removal of P from wastewater, rather than on characterization of the recovered P materials. The objective of this work was to apply microfocused X-ray fluorescence (XRF) spectroscopy, and both bulk and microfused X-ray absorption near edge structure (XANES) spectroscopy, to provide insight into the speciation of recovered P in various struvite-containing and struvite-like materials. Three materials were investigated: homogeneous crystalline struvite on apatite seed, homogeneous dittmarite, and heterogeneous struvite with sand contamination (referred to as the "sandy" material). The struvite materials were recovered from dairy wastewater, whereas the dittmarite was from a cheese processing plant. Phosphorus speciation in the crystalline struvite on apatite seed material was ∼17% apatite and 83% struvite; in the "sandy" material, P was ∼24% apatite and ∼76% struvite, with an uncertainty of approximately ±15%. The P -edge XANES spectra of recovered dittmarite appeared pure. These findings highlight the heterogeneity of recovered P materials and underscore the importance of P speciation to understand P release behavior and bioavailability from recovered phosphates.

Combination of factors that increase the risk of contamination by geohelminths larvae in the south coast of Bahia, Brazil

The lack of basic sanitation and improper pet owner's habits on contaminated environments are essential elements for soil-transmitted helmithiasis. The objective herein was to confirm beach sands contamination by geohelminths larvae and to construct geospatial scenarios combining the factors involved. Sand samples (n=162) were collected by a standardized method and investigated by an adapted microscopy technique. All data were statically tested by Pearson correlation coefficients, Student’s or Tukey’s t tests with 5% of significance. A significant higher contamination of beach sands by geohelminths larvae (p 2 meters) in relation to sea surface. Larvae of Strongyloides stercoralis were more frequent in the beach sands contaminated by improper sanitation and sewage (33%; p < 0.01) and Ancylostoma spp. were more frequent in the beach sand with the presence of dogs (38%; p <0.01). Beach contamination by geohelminths’ larvae increases when a combination of factors occurs such as improper handling of waste, inadequate sewage disposal and the presence of dogs in the highest sites of the shoreline.

Effect of Operation Condition on Gelugur Acid (Garcinia atroviridis) Drying Rate Using Tray Dryer

Garcinia atroviridis is a commodity with promising economic potential in the future, that it is not only used as spices but also as a necessity in cosmetic industry. One of the backgrounds of this research was the abundant amount of Garcinia atroviridis in North Sumatra. The post-harvest of processing Garcinia atroviridis was conducted by conventional drying process, i.e. drying out directly under the scorching sun where it was put on the sack or tarp and in the roads passed by motor vehicles. It had some disadvantages such as, a long drying time, lack of hygiene, contamination of dust and sand, animals and insects plague, as well as uncertain whether circumstances. Therefore, the dryer is very much needed as it can overcome these weaknesses. This research attempted to conduct a drying study of Garcinia atroviridis using tray dryer. It consisted of a drying room equipped with a tray of dried material, air heater, fan, control panel of temperature gauge and relative humidity (RH). The main purpose of this research was to study the influence of operating conditions against the rate of drying and characteristics of drying Garcinia atroviridis. This research was conducted by varying the drying temperature (45 and 55 oC) and air flow rate (1.15 and 2.25 m/s), with a weight of 500 grams Garcinia atroviridis. The drying was done by weighing each ingredient in a specified time interval until reaching constant weight. The results showed that the air flow rate and temperature affected the drying rate, where the 55 oC temperature and 2.25 m/s flow rate could lower the moisture content of 90% within 540 minutes. As for the characteristics of the drying Garcinia atroviridis, it generally showed that there were only two stages of drying rate, namely rising and declining drying rate. But on the operating conditions of the 1.15 m/s air flow rate and 55 oC temperature, it showed three stages namely, rising, constant and declining drying.

Large-scale direct shear tests on sand-contaminated ballast

Significant parts of railway lines in most of the Middle East and Asian countries are in sandy and desert areas. Contamination of tracks (in particular the ballast layer) caused by frequent sand storms in the desert is an important challenge for railway industries. Despite a large number of reported railway accidents caused by the loss of shear strength in the contaminated ballast layer, there is a lack of sufficient studies on the effect of sand contamination on ballast shear strength. In response to this need, extensive laboratory tests on clean and sand-contaminated ballasts were conducted, using a large-scale direct shear test machine designed and constructed in this research. Ballast samples with different dosages of sand contamination were tested. The results obtained are discussed leading to a better understanding of ballast behaviour when contaminated with various amounts of sand. The results show that sand contamination reduces the shear strength and angle of effective shearing resistance of the ballast. The critical percentage of ballast contamination, after which the ballast faces substantial reduction in its mechanical properties, was derived. The results obtained have improved the current ballast maintenance approach by providing the possibility of a more accurate planning of ballast cleaning and renewals.

Effect of sand and clay fouling on the shear strength of railway ballast for different ballast gradations

Ballast contamination by fine materials such as sand and clay in railway track at arid regions is an important issue that causes track instability problems and settlement due to reduction of shear strength of ballast. In this paper, the results of direct shear box test conducted on clean ballast, sand-fouled ballast and clay-fouled ballast for different ballast gradations are reported and discussed. For this purpose, three different fouling amounts according to fouling index are added to clean ballast. Test results show that by increasing the fouling percentage, the ballast shear strength always decreases both for sand and clay fouled ballast. However, the amount of shear strength reduction is low at high normal stresses. Clay contamination has more adverse effect on the shear strength of ballast compared with sand contamination. Also, the results of tests for evaluation of gradation effect on shear strength of fouled ballast which are conducted on various gradations according to American Railway Engineering and Maintenance-of-Way Association, show that the maximum particle size as well as uniformity coefficient affect the shear strength of ballast. Also, an empirical equation is presented to observe the effect of ballast gradation on reduction of shear strength with regard to amount of fouling material and normal stress.

Análise de areia de parques públicos nos municípios de Castelo e Cachoeiro de Itapemirim

Environmental diseases for geo-helminths infected forms compose a big public health problem and veterinary medicine, because they directly affect the human health and of domestic animals. This study aimed to monitor the degree of parasitological contamination of public park sands located in the municipalities of Castelo and Cachoeiro de Itapemirim, Espírito Santo, Brazil. The evaluation of the sanitary quality of the sands of the Beira Rio park, located in the city of Castelo - ES and of the parks of the neighborhoods Vila Rica and BNH, located in the city of Cachoeiro de Itapemirim - ES, was carried out by means of parasitological analyzes using the techniques by Hoffman, Willis, Baermann and the simple centrifugal-flotation technique. From nine sample from dry sand analyzed by traditional techniques it was observed a positive frequency of eggs from Ascarididae, Ancylostomatidae, as well as helminths belonging to the superfamily Trichuroidea. In addition, larvae of Ancylostoma spp. were recovered. The results show a high contamination rate in the sands of Vila Rica Park, and highlight the need to implement prevention and control measures by public agencies that aim at sanitary education of the people and merchants that attend these environments.

Experimental investigation of effects of sand contamination on strain modulus of railway ballast

Ballast layer has an important role in vertical stiffness and stability of railway track. In most of the Middle East countries and some of the Asian ones, significant parts of railway lines pass through desert areas where the track (particularly ballast layer) is contaminated with sands. Despite considerable number of derailments reported in the sand contaminated tracks, there is a lack of sufficient studies on the influences of sand contamination on the ballast vertical stiffness as the main indicator of track stability. Addressing this limitation, the effects of sand contamination on the mechanical behavior of ballast were experimentally investigated. For this purpose, laboratory tests (plate load test) on ballast samples with different levels of sand contamination were carried out. The results obtained were analyzed leading to derive mathematical expressions for the strain modulus (EV) as a function of the ballast level of contamination. The EV was used as an index for evaluation of the load-deformation characteristics and bearing capacity of track substructure. The critical limit of sand contamination, after which the EV of the ballast reduces drastically, was obtained. It was shown that the obtained research results improve the current track maintenance approach by providing key guides for the optimization of ballast maintenance planning (the timing of ballast cleaning or renewal).

Optimization of washing conditions with biogenic mobilizing agents for marine fuel-contaminated beach sands

Washing is a rapid and effective treatment to remediate contaminated sands impacted by oil spills, although synthetic additives used to increase extraction efficiency may cause additional pollution issues due to their intrinsic toxicity and very often low biodegradability. In this study, different biogenic mobilizing agents (soybean lecithins, cyclodextrins, cholic acids, plant-derived cleaners, rhamnolipids and sophorolipids) were tested in the washing of beach sands artificially contaminated with the Intermediate Fuel Oil IFO-180. Among these, a de-oiled soybean lecithin (SL-1), hydroxypropyl-β-cyclodextrins (HPB-CD) and sophorolipids (SR) achieved hydrocarbon removals close to those attained with the synthetic surfactant Triton™ X-100 (TX) in preliminary washing tests carried out at constant mixing rate, water/sand ratio and IFO-180 contamination level using agents concentrations close to their critical micelle concentration (0.1% and 1% w/v for microbial and non-microbial agents, respectively). The effects of agent concentration, water/sand ratio, mixing rate and IFO-180 contamination on hydrocarbons removal were modelled using face-centred central composite design and ANOVA. Optimal washing parameters for sand contamination levels in the range 0.5–20 g/kg were identified with response surface methodology. While HPB-CD and SR performed equally to TX only at low sand contaminations, SL-1 attained hydrocarbon removal higher or equal to that of TX at any IFO-180 contamination and at lower application rates. SL-1 also outperformed TX when minimizing the water/sand ratio, i.e., the volume of water used. Considering its lower toxicity, higher biodegradability and higher hydrocarbon removal efficiencies, SL-1 is an effective and environmentally sustainable alternative to synthetic surfactants in washing treatments for marine fuel-contaminated sands.

Prevalence and Characterization of Staphylococcus aureus and Methicillin-Resistant Staphylococcus aureus on Public Recreational Beaches in Northeast Ohio.

Staphylococcus aureus can cause severe life‐threatening illnesses such as sepsis and endocarditis. Although S. aureus has been isolated from marine water and intertidal beach sand, only a few studies have been conducted to assess prevalence of S. aureus at freshwater recreational beaches. As such, we aimed to determine prevalence and molecular characteristics of S. aureus in water and sand at 10 freshwater recreational beaches in Northeast Ohio, USA. Samples were analyzed using standard microbiology methods, and resulting isolates were typed by spa typing and multilocus sequence typing. The overall prevalence of S. aureus in sand and water samples was 22.8% (64/280). The prevalence of methicillin‐resistant S. aureus (MRSA) was 8.2% (23/280). The highest prevalence was observed in summer (45.8%; 55/120) compared to fall (4.2%; 5/120) and spring (10.0%; 4/40). The overall prevalence of Panton‐Valentine leukocidin genes among S. aureus isolates was 21.4% (15/70), and 27 different spa types were identified. The results of this study indicate that beach sand and freshwater of Northeast Ohio were contaminated with S. aureus, including MRSA. The high prevalence of S. aureus in summer months and presence of human‐associated strains may indicate the possibility of role of human activity in S. aureus contamination of beach water and sand. While there are several possible routes for S. aureus contamination, S. aureus prevalence was higher in sites with wastewater treatment plants proximal to the beaches.

Microplastics elutriation system. Part A: Numerical modeling

The elutriation process has shown its efficiency to extract microplastics from sand and began to spread in the scientific community. This extraction technic requires knowing with accuracy the extraction velocities of particles. This study aims to test whether numerical modeling could help to calculate these velocities. From hydrodynamic equations, a numerical model has been developed and the outputs are compared to experimental extraction data. The results show, for the calculated velocities, the experimental plastic extraction yields will be higher than 90% for <10% of sand contamination. The model also allows determining that, with the actual protocol, the maximum plastic density which can be extracted is about 1450kg·m−3 whereas the detrimental resuspension, which may occur during the column filling step, is highlighted. From model calculations, it arises that changes in the column dimensioning and the protocol operations need to be considered.

Microbiological Sandy Beach Quality in Western Algeria

Microbiological Sandy Beach Quality in Western Algeria Whilst the potential impact on beach users from microorganisms in water has received considerable attention, there has been relatively little investigation into microbial contaminants in sand. From a recreational point of view, sandy beaches are the busiest because they represent a space of relaxation and leisure. Following the large attendance, a possible microbiological contamination of the sand could be a source of pathogenic transmission. Four beaches across western Algeria (Oran) were analyzed during a two-year period (2013–2015) to determine the presence of yeasts, fungi, total coliforms, fecal coliformes, E. coli, Staphylocoques and Pseudomonas in sand. A total of 233 fungi isolates was discerned in the four study areas and an enumeration of 13 genera of nondermatophytic filamentous fungi and five yeast- species belonging to four genera were identified. The fungal species identified in order of importance are: Penicillium spp. Aspergillus, Cladosporium, Fusarium, Rhodoturula, Alternaria spp. Mucor, Candida zeylanoides, Phialophora spp., Cryptococcus albidus, Rhizopus spp., Scopulariopsis spp., Chrysosporium spp., Geotrichum spp., Acremonium spp., Rhizomucor spp., Saccharomyces cerevisiae, Candida albicans. The high level of total coliforms was 18500 cfu/100 ml, fecal coliformes 5400 cfu/100 ml, E. coli 3100 cfu/100 ml, Staphylococci 5400 cfu/100 ml and Pseudomonas 1100 cfu/100 ml. Among this biodiversity, some species are highly pathogenic to humans, and represent a real danger to public health.

Geohelminths eggs contamination of sandpits in Vladivostok, Russia.

To detect nematode eggs in sandpits in urban area in Vladivostok. Totally 60 samples were collected from five districts. Sand samples were analysed using combined flotation-sedimentation method. In result, 18 sand samples were positive for at one or two parasites species. Overall, only 3 genera of helminths were recovered. Most samples were positive for Toxocara spp. eggs. Toxocara spp. eggs were found in each district. More samples with Toxocara spp. eggs were found in Pervomaiskii district. Ascaris spp. eggs were also appeared in each district, however Ascaris eggs rate of contamination was less than rate of Toxocara spp. contamination. Toxascaris leonina eggs were the less frequent species in sandpits, it was found only in Sovetskii and Pervomaiskii districts. Ascaris eggs rate of contamination was less than rate of Toxocara spp. contamination. Toxascaris leonina eggs were the less frequent species in sandpits, it was found only in two districts. No correlation between districts and helmiths eggs present in soil samples was found (P>0.05). Considering the high sand contamination with parasite infective elements of both human and animal origin, measures to improve environmental and sanitary conditions are indicated, as well as promoting the concept of responsible pet ownership.

Influence of the coating level on the heterogeneous ozonolysis kinetics and product yields of chlorpyrifos ethyl adsorbed on sand particles

Heterogeneous oxidation of chlorpyrifos ethyl (CLP) coated sand particles by gaseous ozone was studied. Mono-size sand was coated with CLP at different coating levels between 10 and 100 μg g−1 and exposed to ozone. Results were analyzed thanks to Gas Surface Reaction and Surface Layer Reaction Models. Kinetic parameters derived from these models were analyzed and led to several conclusions. The equilibrium constant of O3 between the gas phase and the CLP-coated sand was independent on the sand contamination level. Ozone seems to have similar affinity for coated or uncoated sand surface. Meanwhile, the kinetic parameters decreased with an increasing coating level. Chlorpyrifos Oxon, (CLPO) has been identified and quantified as an ozonolysis product. The product yield of CLPO remains constant (53 ± 10%) for the different coating level.The key parameter influencing the CLP reactivity towards ozone was the CLP-coating level. This dependence had a great influence on the lifetime of the CLP coated on sand particles, with respect to ozone, which could reach several years at high contamination level.

ЗБЕРЕЖЕННЯ ЖИТТЄЗДАТНОСТІ ЯЄЦЬ ТА ЛИЧИНОК СТРОНГIЛЯТ I АСКАРИДАТ У ДОВКІЛЛІ В ЗИМОВИЙ ПЕРІОД

This paper presents the results of the helminthological study of sand, hay and silage in different periods of 2010 – 2015. It was established that on the territory of Polissya the eggs and larvae of nematodes (Parascaris equorum, Strongylidae sp., Toxocara canis) at typical winter air temperature (-15 – +3 °C) remain viable in the environment, contributing to the spread of continuous year-round animal infestation.We prove that in the stall period of keeping animals rough and succulent feed (hay, silage) can be a source of infection of nematodes even in late winter: according to our data, in February in the hay the number of eggs P. equorum was 2.6 ± 0.74 eggs/3 drops of flotation solution, in the silage – 8.8±1.01, and Strongylidae sp. – 3.2 ± 0.73 and 5.6 ± 0.6 eggs/3 drops of flotation solution respectively. Consequently, for the prevention of helminthiasis all harvested food should be checked for the presence of pathogens in it.Maximum contamination of sand from playgrounds in the Zhytomyr region by toxocara eggs was: 674.6 eggs/3 drops of flotation solution in autumn and 60.3 – in the spring. Totally 12.8–18.4% of T. canis eggs are overwintering in the sand successfully. The data should be considered when planning preventive veterinary measures. Recommended in disadvantaged regions to carry out preventive deworming animals every 3 months.

Sediment characteristics and microbiological contamination of beach sand – A case–study in the archipelago of Madeira

Beach sand can harbour pathogenic and opportunistic microorganisms, as well as faecal indicator bacteria that influence directly the bathing water quality. Pathogenic and opportunistic microorganisms often raise concern of exposure during beach related recreational activities. In this work, three different types of sandy beaches (natural basaltic, natural calcareous and artificial calcareous) of the Archipelago of Madeira (Portugal) were sampled for bacterial and fungal contaminants and grain size distribution, during four years (2010−2013). Following an extreme weather event in 2010, the faecal indicator bacteria levels spiked, returning to base levels shortly thereafter. The same phenomenon occurred with fungi, where potentially pathogenic fungi were the dominant group. Yeast-like fungi and dermatophytes were, however, mainly associated to months of higher usage by recreational users. Statistical analysis showed higher contamination of sediment in artificial beaches compared to natural beaches and granulometry and chemical composition of sand did not influence in the microbial loads. Instead, bather density and the influence of coastal protection structures needed to maintain the volume of artificial beach sand regarding the removal potential of wave induced currents are obvious influencing factors.

Contamination of beach sand by hookworm species: a small scale observation from Thailand

Hookworm is an important tropical nematode. The worm is a roundworm that can be seen in many tropical areas. Basically, this roundworm can cause gastrointestinal infection and chronic infection and result in hypochromic microcytic anemia, which is the common public health problem. Focusing on the worm’s life cycle, the hookworm egg will be passed from intestine of infected host and hatched as larva in the soil. Based on this information, bearfooted walking is at risk. In general, hookworm is a geohelminth. It usually lives in the sand and penetrates the human’s foot to cause infection. Hence, the analysis of the contamination of hookworm in sand can give useful data for disease surveillance and control. The contact to contaminated sand can be the primary origin of the infection[1]. Bojar and Klapec noted that “attention should also be paid to the possibility of contamination of recreational areas with the eggs of intestinal parasites by wild animals[2].” An interesting forgotten concern is the possible contamination of hookworm in sand at beach. According to a report by Mabaso et al., “amounts of fine and medium sand were highest in both the coastal plain soils and in inland sandy areas and these fractions showed a significant positive correlation with hookworm prevalence and nematode loadings[3].” There is an interesting previous report showing the possibility of contamination in sand beach[4]. In some beaches, 42% of the samples were contaminated with Ancylostoma larvae[4]. Here, the authors reported the observation on contamination of beach sand by hookworm species in sample collected from 3 beaches in Thailand. The standard soil analysis as previously described by Wiwanitkit and Waenlor was used[5]. According to the analysis, null prevalence could be observed. This can imply the cleanness of the studied beaches. The situations in other beaches have to be studied and verified. Since bare-footed walking in the beach is usual, the risk of getting hookworm infestation in dirty beach has to be notified to the general people. In additional, the use of alternative biological control of the worm is the new method to be notified. De Mello et al. mentioned the efficiency of the Duddingtonia genus in the control of Ancylostoma spp. infective larvae[6].

Statistical assessment of heavy metal distribution and contamination of beach sands of Antalya-Turkey: An approach to the multivariate analysis techniques

The distribution of heavy metal concentrations in the beach sand samples collected from 44 different locations along the Manavgat Alanya coastline of Antalya covering different coastal sandy beaches was studied. The average concentration level of these metals in the beach sand was calculated and compared to those of the Earth Crust, Sandstone, Ultrabasic Rock and the acceptable limit for Turkey in order to determine their anomalies. Heavy metal (Cr, Zn, Ni, As, Cu, Pb, Co, Mo, Sb and Cd; along with Al, Fe, Mg, Mn, Na, K, Ba, Ca and W) were determined. The elements occurred in abundance as Ca&gt;Na&gt;Mg&gt;Fe&gt;Al&gt;K&gt;Ti&gt;Mn&gt;Cr&gt;Ba&gt;V&gt;Zn&gt;Ni&gt;As&gt;Cu&gt;Pb&gt;Co&gt;Mo&gt;Sb&gt;W&gt;Cd. The sufficiency of the number of samples used from the study area is revealed by the high explanatory power R2 = 96:9 % of the ANOVA Model. Using the box plot, it was also noted that some heavy metals such as As (in samples 1, 19, 25, 28 and 29); Mn (in Samples 23 and 39); Na (in samples 23, 24 and 45); Cr (in Sample 33) and Ti (in Sample 15) had very high anomalies. Heavy metal contents show high anomaly concentrations when compared to some background values (Earth Crust, Sandstone, Ultrabasic and Turkey acceptable limit).

Nutritional Value and Seasonal Availability of Feed Ingredients for Pigs in Uganda

Abstract In this study nutritional values and seasonal availability of 43 local feed ingredients for pigs in Uganda, were estimated based on nutrient analyses and literature values, information needed to develop low-cost balanced rations for pigs on smallholder farms. Parameters considered were: concentration of ash, neutral detergent fibre (NDF), crude protein (CP), calcium (Ca), phosphorous (P), ether extract (EE), total lysine (Lys), standardized ileal digestible (SID) Lys, standardized total tract digestible (STTD) P (all as % of dry matter [DM]); digestible energy (DE), (kcal kg−1 of DM); and DM concentration. Concentration of DE, total Lys, SID Lys, and STTD P were estimated. Ingredient seasonal availability and relative importance were identified. Ground sun-dried fish (Rastrineobola argentea) had highest estimated DE concentration and Napier grass (Pennisetum purpureum) had lowest (4209 and 535 kcal kg−1 of DM, respectively). Ground sun-dried fish had highest CP and estimated total Lys concentration (59.9 and 6.7% of DM, respectively) and banana peel (Musa sapientum), had lowest (5.21 and 0.08% of DM, respectively). Milled ingredients sampled here had higher ash than in the literature (e.g. ground sun-dried fish 58.1 vs 15.9% of DM) likely indicating sand contamination. There were 3 seasons of availability of ingredients. Banana peel, maize bran, and sweet potato vine (Ipomoea batatas) were ranked highest; and commercially-prepared ration, and kale/collard greens (Brassica oleracea var. acephala), were ranked lowest as potential feed ingredients. Ingredients with nutritional profiles suitable for pigs are available but some only in certain seasons. Estimated nutritional values may assist in ration formulation.

Sublethal health effects in laboratory rodents from environmentally relevant exposures to oil sands contaminants.

Increasing activity of oil sands extraction and processing in northern Alberta is marked by ongoing controversy about the nature and extent of associated environmental impacts. Bitumen contains a mixture of toxic chemicals, including metals and residual polycyclic aromatic hydrocarbons (PAHs), whose release into the environment poses a distinct risk to the surrounding environment, plus wildlife and human health. In the present study, the authors evaluated several subclinical biomarkers of exposure and effect to mixtures of metals (Pb, Cd, and Hg) and/or PAHs (3 alkylated forms) at environmentally relevant concentrations (100-fold and 10-fold higher than the maximum dissolved concentrations found in snow, to simulate a worst-case scenario), using laboratory mice as a model for future studies of small mammals in the wild. Both metals and alkyl-PAHs exposure were associated with 1) increased relative liver, kidney, and spleen size; 2) alterations in the homeostasis of the antioxidant vitamins A and E in liver; and 3) compromised glutathione redox status in testes, with results also indicating synergistic interactions from co-exposure. The combination of morphometric and oxidative stress biomarkers provide reliable and sensitive measures of the response to contaminant exposure in a mammalian model, suggesting associated physiological costs. Based on the present experimental study, the authors propose that wild small mammals will prove to be valuable sentinel species reflecting sublethal health effects from oil sands-related contaminants. The present study's results also present a basis for the interpretation of future field data.