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PURPOSE:Rural communities in Australia have an elevated risk of suicide. The aim of the current study was to evaluate a well-being and suicide prevention education workshop, SCARF (Suspect, Connect, Ask, Refer, Follow-Up) developed for Australian farming and rural communities. METHODS:The SCARF program was delivered to 14 groups, a convenience sample including frontline agricultural workers and farmers from New South Wales. The Literacy of Suicide Scale, Stigma of Suicide Scale, and items assessing confidence to assist others were administered immediately before and after the workshop, and at 3-month follow-up. The Warwick Edinburgh Mental Wellbeing Scale was given immediately before and at 3-month follow-up. In total, 255 agreed to participate in the study, with 127 completing 3-month follow-up. Data were analyzed using linear mixed-effects regression. FINDINGS:There was a significant increase in suicide literacy and confidence to assist others immediately after the workshop, which remained significant at 3-month follow-up. Mental well-being significantly improved at 3-month follow-up. CONCLUSION:The SCARF program is unique for its brevity, cultural specificity, focus on health, and incorporation of the biopsycho-ecological model and the Interpersonal Theory of Suicide. It represents a useful program for Australian farming and rural communities to improve mental well-being, suicide literacy, and confidence to recognize and respond to suicidality.

Bicarbonate is often a major ionic constituent associated with produced waters from methane gas extraction and coal mining, yet few studies have determined its specific toxicity. Currently, the environmental risk of bicarbonate anion in water discharges is assessed based on the toxicity of sodium chloride or artificial seawater and is regulated via electrical conductivity. Increased NaHCO3 added to Ceriodaphnia dubia in synthetic or natural water gave similar 48-h 10% effective concentration (EC10) values of 1750 ± 125 mg NaHCO3/L (mean ± standard error) and 1670 ± 180 mg NaHCO3/L, respectively. Bicarbonate was toxic to C. dubia in both waters with conductivities above 1900 µS/cm. In contrast, when conductivity was elevated with NaCl, toxicity to C. dubia was observed only above 2800 µS/cm. Bicarbonate also impaired C. dubia reproduction with an EC10 of 340 mg NaHCO3/L. Major ion composition also influenced Zn bioavailability, a common co-occurring metal contaminant in coal mine waters, with sublethal concentrations of NaHCO3 and elevated pH increasing Zn toxicity. Higher pH was the dominant parameter determining a 10-fold increase in the 48-h 50% effective concentration (EC50) for Zn toxicity to C. dubia at pH 8.6 of 34 µg Zn/L (95% confidence limit = 32–37 µg Zn/L) compared with the Zn toxicity at approximately circumneutral pH. Exposure of the freshwater shrimp Paratya australiensis (Atyidae) in natural water to increasing bicarbonate gave a mean 10-d 10% lethal concentration (LC10) of 850 ± 115 mg NaHCO3/L, associated with a mean conductivity EC10 of 1145 µS/cm, which is considerably lower than toxicity of NaCl and artificial seawater to this species reported elsewhere. Because toxicity was influenced by salt composition, specific ions should be regulated rather than conductivity alone in mine wastewater discharges. Environ Toxicol Chem 2014;33:1179–1186. © 2014 SETAC

The reproductive biology of amphipods is reviewed to update the knowledge of the male and female reproductive processes of oogenesis and spermatogenesis as well as the endocrine systems of amphipods with the aim of advancing studies of reproductive toxicology. The ovarian and reproduction cycles of female gammaridean amphipods are closely correlated with the molt cycle, which is under direct control by the steroid hormone 20-hydroxyecdysone. The ability of males to copulate and subsequently for females to ovulate is restricted to the early postmolt period of the females. New developments in our understanding of the molt cycle and the endocrine regulatory pathways for reproduction using genomics techniques on other crustacean species are also discussed. The arthropod sterol ponasterone A or xenobiotics such as the fungicide fenarimol have been shown to elicit endocrine disruption in some crustaceans by acting as an agonist for 20-hydroxyecdysone at the ecdysone receptor or by inhibiting the synthesis of 20-hydroxyecdysone, respectively, resulting in disruption of molting and reproduction. Recent studies suggest that cadmium can inhibit secondary vitellogenesis in amphipods. Experimental approaches for examining the metabolic pathways associated with ecdysteroid hormonal signaling or metabolism, exoskeleton maintenance and molting, and the regulation of vitellogenin in amphipods are discussed. This information should aid in the identification of useful biomarkers for reproductive toxicity.

An underlying assumption of laboratory-based toxicity tests is that the sensitivity and exposure of organisms in the laboratory is comparable to that in the field. We sought to make a comparison between field-based and laboratory-based sediment toxicity tests using a recently developed rapid amphipod reproduction test that encompasses gametogenesis, fertilization, and embryo development before hatching. The test species, Melita plumulosa, is an epibenthic, detritivorous amphipod native to Eastern Australia. Test sediments were sourced from Lake Macquarie, a large saltwater lagoon located 100 km north of Sydney (New South Wales, Australia) that has received heavy-metal pollution over many decades, primarily from a Pb/Zn smelter but also from collieries, coal-fired power stations, and urban areas. This has led to a north-south trace-metal concentration gradient, including Pb, Zn, Cd and Cu, in the sediments of Lake Macquarie. Sediments from these northern bays were demonstrated to reduce amphipod fecundity in laboratory-based tests. For the current study, the amphipod reproduction test has been modified for use in situ. In situ test chambers were deployed at the mouth of Cockle Creek, Lake Macquarie. Sediments that were demonstrated to reduce fecundity of M. plumulosa in the laboratory reproduction test were not similarly toxic when amphipods were exposed to the same sediments in situ. Factors related to the regular tidal renewal of overlying water likely altered exposure profiles in situ, including the provision of additional or alternative nutrition that obviated the need for amphipods to interact with the contaminated sediments, and a washout effect that prevented the accretion of dissolved zinc in the overlying water. Environ. Environ. Toxicol. Chem. 2010;29:2566-2574. © 2010 SETAC Copyright © 2010 SETAC.

The chronic toxicity of dietary cadmium to the saltwater cladoceran Moina monogolica Daday and its relative toxicity compared with aquatic exposure were investigated in the present study. The microalgae Chlorella pyrenoidosa, exposed to cadmium in growth inhibition tests, had a 96-h median effective concentration (EC50) of 81.2 µg Cd/L (95% confidence intervals [CIs] = 71.9–95.1). C. pyrenoidosa exposed for 96 h to sublethal dissolved cadmium concentrations in the range 4.10 ± 0.30 to 70.29 ± 0.31 µg/L resulted in algal cadmium burdens up to 73.86 × 10−16 g Cd/cell. Cellular cadmium burdens accumulated in a dose-dependent manner, whereas cell densities inversely declined from 670 × 104 to 38 × 104 cells/ml with exposure to the increasing aqueous cadmium concentrations. C. pyrenoidosa preexposed to cadmium and used as food in a chronic 21-d toxicity test with the cladoceran M. monogolica, containing no added dissolved cadmium, inhibited reproduction. Significant reductions of the net reproduction rate (R0) per brood were observed in all broods, and the decline in the number of neonates produced increased with each subsequent brood. The cadmium concentration (4.10 ± 0.30 µg/L) in the algal culture water that produced the lowest algal cadmium burden (2.85 ± 0.76 × 10−16 g Cd/cell) was shown to inhibit M. monogolica reproduction and was compared with the water quality criteria (WQC) of China. This comparison indicated that dietary exposure to cadmium may cause sublethal responses at concentrations below the current cadmium WQC of China for aquaculture. Environ. Toxicol. Chem. 2010;29:365–372. © 2009 SETAC

A laboratory continuous-flow system delivering known aqueous concentrations of pesticides to passive samplers was used to examine the kinetics of pesticide uptake and release. The passive samplers were constructed of low-density polyethylene membrane bags containing 2,2,4-trimethylpentane solvent (TRIMPS). Both uptake and release experiments were run in triplicate. Each experiment involved four treatments, including a control and three fivefold dilutions of a pesticide mixture that included the usual range of these pesticides as measured in the riverine environment of cotton-growing regions of Australia. The results indicated that for nonpolar pesticides with a log K o w > 3.5, uptake was linear over the 42-d exposure time and was independent of the treatment concentration. The half-lives for release of these pesticides from the TRIMPS varied from 26 to 130 d in clean water. The relatively polar pesticides with a log K o w < 3.5 had lower uptake rates into the TRIMPS because of their affinity for water. Release of trimethylpentane from the TRIMPS placed in 0.85-mm mesh nylon bags in river water was used as an indicator for chemical diffusion across the aqueous boundary to examine the effect of environmental factors. Most variability in solvent release in the field-deployed TRIMPS across all sites was explained by time of deployment and was not significantly influenced by river flow or water temperature. This suggests that river flow and water temperature may not be important in influencing uptake rates of pesticides into TRIMPS when employed in the field.

Transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) are popular and powerful techniques used to characterize heterogeneous catalysts. Rapid developments in electron microscopy – especially aberration correctors and in situ methods – permit remarkable capabilities for visualizing both morphologies and atomic and electronic structures. The purpose of this review is to summarize the significant developments and achievements in this field with particular emphasis on the characterization of catalysts. We also highlight the potential and limitations of the various methods, describe the need for synergistic and complementary tools when characterizing heterogeneous catalysts, and conclude with an outlook that also envisions future needs in the field.

A method for assessment of the human sperm acrosome reaction is reported using fluorescein isothiocyanate (FITC)-conjugated Concanavalin A (ConA). The technique involved labelling prefixed spermatozoa, where only those spermatozoa that showed a complete loss of the acrosome bound FITC-ConA to the acrosomal region. Competitive sugar binding studies demonstrated that binding of ConA lectin to the acrosomal area of human spermatozoa was inhibited in the presence of 0.2 M D-mannose. Staining with the supravital stain Hoechst 33258 (H258) concomitantly with FITC-ConA allowed determination of only those spermatozoa that had undergone a true and not degenerative acrosomal loss. Incubation of human spermatozoa with 0, 1, 5, and 25 microM calcium ionophore, A23187, for 60 min demonstrated that changes in acrosomal status due to the different treatment protocols may be determined by the dual-staining method. Electron microscopy studies revealed that gold-conjugated ConA bound specifically to the surface of the inner acrosomal membrane of acrosome-reacted spermatozoa. A significant correlation (r = +.97) between transmission electron microscopy (TEM) and FITC-ConA labelling methods of acrosomal status assessment was achieved. The simple ConA labelling procedure reported here therefore provides a reliable method for quantitation of the physiological acrosome reaction of a population of human spermatozoa.

Laboratory survival tests were conducted with an indigenous infaunal amphipod, Corophium colo, on 103 sediment samples from Sydney Harbor (NSW, Australia) and vicinity, containing a wide range of chemicals and concentrations. The present study describes the sensitivity of C. colo to the sediments and compares the results to data for North American amphipods (Rhepoxynius abronius and Ampelisca abdita) previously used to establish and validate sediment-quality guidelines (SQGs). The incidence of toxicity increased with increasing contamination, as indicated by increasing numbers of SQGs exceeded and increasing mean SQG quotients. The incidence of highly toxic results (p0.05 and mean amphipod survival of80% that of controls) for highly contaminated samples was approximately half (28-40%) that of a large U.S. database (74%). The incidence of highly toxic responses for samples with intermediate levels of contamination also was lower in the present study (5-13%) compared to the results in large U.S. studies (approximately 30-50%). Corophium colo reburial tests showed greater sensitivity compared to survival tests, with a maximum incidence of statistically significant responses in moderately contaminated sediments of 70%. The present study showed that adult Corophium organisms are suitable for testing lethal responses in highly contaminated sediments (i.e., with mean effects range-median quotients of1.5). Reburial results provide additional sensitivity.

This study determined the influence of key water chemistry parameters (pH, alkalinity, dissolved organic carbon [DOC], and hardness) on the aqueous speciation of copper and zinc and its relationship to the acute toxicity of these metals to the cladoceran Ceriodaphnia cf dubia. Immobilization tests were performed for 48-h in synthetic or natural waters buffered at various pH values from 5.5 to 8.4 (other chemical parameters held constant). The toxicity of copper to C. cf dubia decreased fivefold with increasing pH, whereas the toxicity of zinc increased fivefold with increasing pH. The effect of DOC on copper and zinc toxicity to C. cf dubia was determined using natural fulvic acid in the synthetic water. Increasing DOC was found to decrease linearly the toxicity of copper, with the mean effect concentration of copper that immobilized 50% of the cladocerans (EC50) value 45 times higher at 10 mg/L, relative to 0.1 mg/L DOC at pH 6.5. In contrast, the addition of 10 mg/L DOC only resulted in a very small (1.3-fold) reduction in the toxicity of zinc to C. cf dubia. Copper toxicity to C. cf dubia generally did not vary as a function of hardness, whereas zinc toxicity was reduced by a factor of only two, with an increase in water hardness from 44 to 374 mg CaCO3/L. Increasing bicarbonate alkalinity of synthetic waters (30-125 mg/L as CaCO3) decreased the toxicity of copper up to fivefold, which mainly could be attributed to the formation of copper-carbonate complexes, in addition to a pH effect. The toxicity of copper added to a range of natural waters with varying DOC content, pH, and hardness was consistent with the toxicity predicted using the data obtained from the synthetic waters.

The rate of release of three performance reference compounds (PRCs) from passive samplers when deployed in rivers with variable flow and temperature were compared with their release from passive samplers in a laboratory continuous-flow system. The passive samplers used in the current study were constructed from low-density polyethylene bags containing trimethylpentane solvent (TRIMPS). The half-lives for release from the TRIMPS of the PRCs tributylphosphate, endosulfan sulfate, and chlorpyrifos-ethyl were 7.3, 20.8, and >75 d, respectively, when deployed in rivers, compared with half-lives of 10.4, 26.5, and approximately 73 d in a laboratory flow system. The mean pesticide concentrations taken up by TRIMPS deployed for periods from 7 to 22 d in rivers adjacent to cotton fields were determined during two studies in the austral summer of 2000/2001 and 2001/2002. During the studies, mean total endosulfan and chlorpyrifos-ethyl concentrations were also determined from daily river-water extractions. Regression equations established in previous laboratory studies related the concentration factors into TRIMPS to the time of deployment for a number of pesticides, including endosulfan and chlorpyrifos-ethyl. The laboratory-derived calibration factors were used to determine the mean pesticide concentrations for each deployment period, and these were compared with the cumulative mean concentrations calculated from the daily extractions. The pesticide concentrations determined using the TRIMPS were within twofold of the cumulated mean of the daily river-water extractions of endosulfan and chlorpyrifos-ethyl for deployment periods of 7 to 22 d when the mean river-water concentrations were >0.005 microg/L.

Static bioassays were conducted to determine effects of water hardness on toxicity of sodium fluoride to rainbow trout (Salmo gairdneri). Ninety-six hour LC50 values increased from 51 to 193 mg/L [F] as water hardness levels rose from 17 to 385 mg/L CaCO3. Tests of chronic toxicity at different water hardness levels are needed before fluoride standards for aquatic life, such as fish, can be set.

Estimates were made of the amounts of selected pesticides entering and leaving Saylorville Reservoir, a new partly filled impoundment on the Des Moines River. Samples were collected at 1– or 2-week intervals at stations above, in, and below the reservoir. Atrazine, alachlor, and cyanazine were found only in the dissolved state, and dieldrin and p, p′ -DDE in both the, dissolved and suspended state. Heptachlor epoxide, p,p-DDT. p, p′ -DDD, 2,4-D, 2,4,5-TP, endrin, lindane, methoxychlor, propachlor, and toxaphene were not detected or were at very low concentrations. Estimated deposition in the reservoir from September 1977 to October 1978 was 281 kg atrazine, 251 kg alachlor, 26 kg cyanazine, 16 kg dieldrin, and 20 kg p, p′ -DDE.

After capacitation of guinea pig spermatozoa in vitro, the plasma membrane was mechanically separated from the spermatozoa in the presence or absence of HgCl2 and subsequently isolated by density gradient centrifugation. Examination of the spermatozoa by electron microscopy after homogenization in the presence of HgCl2 revealed that plasma membrane was removed only from the acrosomal region and remained predominantly intact posterior to the equatorial segment of the sperm head, as well as the midpiece and tail. In comparison, spermatozoa homogenized under similar buffer conditions but in the absence of HgCl2 lose the large apical segment of the acrosome and the plasma membrane is removed essentially from the entire cell. If spermatozoa were homogenized in the absence of Hg2+, analysis of plasma membrane phospholipid composition revealed a complete loss of lysophosphatidylcholine (LPC) from the plasma membrane after incubation of spermatozoa in minimal capacitating medium (MCM-PL) for 2 hours. Under these culture conditions the addition of Ca2+ (5 mM) to the capacitated spermatozoa induced approximately 78 +/- 5% (n = 3) of the motile spermatozoa to undergo acrosome reactions while still maintaining sperm motility (80 +/- 5%) (n = 3). If the spermatozoa were homogenized in the presence of Hg2+, a time course study revealed that plasma membrane LPC loss occurred between 60 and 90 minutes of incubation. This complete loss of LPC was evident when approximately half of the capacitated spermatozoa had undergone acrosome reactions. Incubation of the spermatozoa with the metabolic and acrosome reaction inhibitor, 2-deoxyglucose (10 mM) for 2 hours, maintained the plasma membrane phospholipid composition similar to that in the noncapacitated state. These data provide evidence that changes in the plasma membrane phospholipid composition may be associated with guinea pig sperm capacitation.