An in vitro/in vivo screening assay as a sensitive tool to assess endocrine disruptive activity in surface water

Adult male fathead minnow were exposed for 14 or 28-days under flow-through conditions to undiluted filtered water samples from the rivers Meuse and Rhine in the Netherlands. The experiment included two vessels per treatment each containing 10 fish and samples of five fish were taken after 14 and 28 days. Additional groups were exposed to 17alpha-ethinylestradiol (EE2) as a reference and untreated drinking water as a negative control. Major endpoints examined included induction of vitellogenin (VTG) synthesis, VTG mRNA activity, hepato- and gonadosomatic indices (HSI and GSI) and gonadal histology. No significant difference was recorded in body weight or mean GSI values between the various treatments. Only exposure to Meuse water resulted in significantly higher HSI means after 14 days. Histological examination showed no apparent effects on gonadal tissue except for eosinophilic blood plasma in fish exposed to Meuse water or EE2. After 14 and 28 days, elevated VTG and VTG mRNA levels were measured in most livers of the fish exposed to Meuse water, but not in the fish exposed to Rhine water. This was confirmed by measuring estrogenic responses in the in vitro ER CALUX assay. Induction of VTG synthesis proved to be the most sensitive endpoint in the Non Spawning Male Fish Assay for in vivo detection of bio-available estrogenic activity supplementary to a sensitive in vitro assay. The other endpoints examined varied too much and required a higher number of fish or replicates to achieve sufficient power for statistical testing making them less animal friendly.     

Acute toxicity tests with Daphnia magna, Americamysis bahia, Chironomus riparius and Gammarus pulex and implications of new EU requirements for the aquatic effect assessment of insecticides

Threshold concentrations for treatment related effects of 31 insecticides, as derived from aquatic micro-/mesocosm tests, were used to calibrate the predictive value of the European Tier-1 acute effect assessment on basis of laboratory toxicity tests with Daphnia magna, Chironomus spp., Americamysis bahia and Gammarus pulex. The acute Tier-1 effect assessment on basis of Daphnia (EC(50)/100) overall was protective for organophosphates, carbamates and most pyrethroids but not for neonicotinoids and the majority of insect growth regulators (IGRs) in the database. By including the 28-day water-spiked Chironomus riparius test, the effect assessment improves but selecting the lowest value on basis of the 48-h Daphnia test (EC50/100) and the 28-day Chironomus test (NOEC/10) is not fully protective for 4 out of 23 insecticide cases. An assessment on basis of G. pulex (EC(50)/100) is sufficiently protective for 15 out of 19 insecticide cases. The Tier-1 procedure on basis of acute toxicity data (EC(50)/100) for the combination of Daphnia and A. bahia and/or Chironomus (new EU dossier requirements currently under discussion) overall is protective to pulsed insecticide exposures in micro-/mesocosms. For IGRs that affect moulting, the effect assessment on basis of the 48-h Chironomus test (EC(50)/100) may not always be protective enough to replace that of the water-spiked 28-day C. riparius test (NOEC/10) because of latency of effects.     

Spiders in mountain habitats of the Giant Mountains

Ground-living spiders were studied using modified pitfall traps during several years in four characteristic habitats in Giant Mountains (Krkono?e Mts.), the High Sudetes, Czech Republic: alpine tundra, subalpine mire, tall-herb stand at the bottom of a glacial corrie, and decaying mountain spruce forest. Ecological and zoogeographical aspects of spider communities were analysed. The spider communities of alpine tundra, subalpine mire, and glacial corrie exhibited long-term stability, whereas the community of decaying mountain forest changed during observations. Small linyphiid spiders, dominating in mature forest, were gradually replaced by larger Iycosid and gnaphosid species. Zoogeographic characterization of mountain habitats was made based on species exhibiting disjunctive area. In contrast to plants, for spiders of boreal origin alpine tundra is the most important habitat for survival, followed by screes, mires, spruce forests, and corries.     

Assessment of Spatiotemporal Varying Relationships Between Rainfall,Land Cover and Surface Water Area Using Geographically Weighted Regression

Traditional regression techniques such as ordinary least squares (OLS) are often unable to accurately model spatially varying data and may ignore or hide local variations in model coefficients. A relatively new technique, geographically weighted regression (GWR) has been shown to greatly improve model performance compared to OLS in terms of higher R ² and lower corrected Akaike information criterion (AIC_C). GWR models have the potential to improve reliabilities of the identified relationships by reducing spatial autocorrelations and by accounting for local variations and spatial non-stationarity between dependent and independent variables. In this study, GWR was used to examine the relationship between land cover, rainfall and surface water habitat in 149 sub-catchments in a predominately agricultural region covering 2.6 million ha in southeast Australia. The application of the GWR models revealed that the relationships between land cover, rainfall and surface water habitat display significant spatial non-stationarity. GWR showed improvements over analogous OLS models in terms of higher R ² and lower AIC_C. The increased explanatory power of GWR was confirmed by the results of an approximate likelihood ratio test, which showed statistically significant improvements over analogous OLS models. The models suggest that the amount of surface water area in the landscape is related to anthropogenic drainage practices enhancing runoff to facilitate intensive agriculture and increased plantation forestry. However, with some key variables not present in our analysis, the strength of this relationship could not be qualified. GWR techniques have the potential to serve as a useful tool for environmental research and management across a broad range of scales for the investigation of spatially varying relationships.     

Revisions to the derivation of the Australian and New Zealand guidelines for toxicants in fresh and marine waters

The Australian and New Zealand Guidelines for Fresh and Marine Water Quality are a key document in the Australian National Water Quality Management Strategy. These guidelines released in 2000 are currently being reviewed and updated. The revision is being co-ordinated by the Australian Department of Sustainability, Environment, Water, Population and Communities, while technical matters are dealt with by a series of Working Groups. The revision will be evolutionary in nature reflecting the latest scientific developments and a range of stakeholder desires. Key changes will be: increasing the types and sources of data that can be used; working collaboratively with industry to permit the use of commercial-in-confidence data; increasing the minimum data requirements; including a measure of the uncertainty of the trigger value; improving the software used to calculate trigger values; increasing the rigour of site-specific trigger values; improving the method for assessing the reliability of the trigger values; and providing guidance of measures of toxicity and toxicological endpoints that may, in the near future, be appropriate for trigger value derivation. These changes will markedly improve the number and quality of the trigger values that can be derived and will increase end-users’ ability to understand and implement the guidelines in a scientifically rigorous manner.     

Arsenic and other trace elements in groundwater and human urine in Ha Nam province,the Northern Vietnam: contamination characteristics and risk assessment

The contamination characteristics of arsenic and other trace elements in groundwater and the potential risks of arsenic from the groundwater were investigated. Elevated contamination of arsenic, barium and manganese was observed in tube-well water of two villages (Chuyen Ngoai and Chau Giang) in Ha Nam province in the Northern Vietnam. Concentrations of As in the groundwater ranged from 12.8 to 884 µg/L with mean values in Chuyen Ngoai and Chau Giang were 614.7 and 160.1 µg/L, respectively. About 83 % of these samples contained As concentrations exceeding WHO drinking water guideline of 10 μg/L. The mean values of Mn and Ba in groundwater from Chuyen Ngoai and Chau Giang were 300 and 657 μg/L and 650 and 468 μg/L, respectively. The mean value of Ba concentration in groundwater in both Chuyen Ngoai and Chau Giang was about 22 % of the samples exceeded the WHO guideline (700 µg/L). Arsenic concentrations in human urine of residents from Chuyen Ngoai and Chau Giang were the range from 8.6 to 458 µg/L. The mean values of Mn and Ba in human urine of local people from Chuyen Ngoai were 46.9 and 62.8 μg/L, respectively, while those in people from Chau Giang were 25.9 and 45.9 μg/L, respectively. The average daily dose from ingesting arsenic for consuming both untreated and treated groundwater is from 0.02 to 11.5 and 0.003 to 1.6 μg/kg day, respectively. Approximately, 57 % of the families using treated groundwater and 64 % of the families using untreated groundwater could be affected by elevated arsenic exposure.     

Does vehicle colour influence crash risk?

An often asked question regarding vehicle safety is whether vehicle colour has an influence on crash risk and if so, what is the differential in risk between the various colours of vehicles available. The major objective of this study was to assess the relationship between vehicle colour and crash risk through the analysis of real crash outcomes described in Police reported crash data. The study employed induced exposure methods utilising single vehicle crashes as the comparison crash type. It estimated the crash risk associated with each vehicle colour relative to a reference colour which was chosen to be white. Results of the analysis identified a clear statistically significant relationship between vehicle colour and crash risk. Compared to white vehicles, a number of colours were associated with higher crash risk. These colours were black, blue, grey, green, red and silver. The association between vehicle colour and crash risk was strongest during daylight hours where relative crash risks were higher for the colours listed compared to white by up to around 10%. No colour had a statistically significantly lower crash risk than white although crash risks for a number of other colours were not statistically significantly different from white.     

Older driver retraining: An updated systematic review of evidence of effectiveness

Problem and Objective

The number of older drivers who might benefit from driver retraining is growing. A previous review on the effectiveness of older driver retraining included intervention studies up to 2004. The objective was to perform an updated systematic review of the effectiveness of older driver retraining for improving driving-related skills and reducing crash rates.

Method

Articles published from 2004-2008 were grouped according to the intervention provided and outcome studied. Randomized clinical trials (RCTs) were appraised using the Physiotherapy Evidence Database (PEDro) Scale and scored for quality according to their internal validity. Each intervention's effectiveness was then rated and assigned a level of evidence by combining pre- and post- 2004 findings.

Results

Three RCTs and one matched-pairs cohort design met the inclusion criteria. There is strong evidence (Level 1a) that education combined with on-road training improves driving performance and moderate evidence (Level 1b) that it improves knowledge. There is moderate evidence (Level 1b) that physical retraining improves driving performance. There is moderate evidence (Level 1b) that an educational intervention curriculum alone is not effective in reducing crashes.

Summary

The updated evidence on the effectiveness of retraining aimed at older drivers is sufficiently encouraging to merit assertive health promotion actions regarding intervention and program planning.

Impact on Industry

These positive findings warrant a comprehensive plan that has both behavioral and monetary incentives encouraging older driver participation in programs aimed at driver safety.     

Deriving environmental quality standards in European surface waters: when are there too few data?

Recent technical guidance has been published by the European Commission that outlines methodologies for the derivation of Environmental Quality Standards (EQS) in European surface waters under the Water Framework Directive (WFD). The guidance allows the derivation of a long-term EQS from a small dataset. Specifically an EQS can be derived from just three acute data points, although the safety factors built into such an EQS are large (e.g. up to a factor of 1,000). Large safety factors make such EQS uncertain, and often difficult to achieve in practice. We examine dataset requirements for the derivation of EQS and specifically the minimum number of tests needed for setting EQS for long-term chemical exposures that result in reduced relative uncertainty, as assessed simply through the reduction in standard deviation of the means of the values derived. Using ecotoxicity datasets for four example chemicals, for which EQS have been derived in many jurisdictions, we show that variation in the EQS is greatest when using the minimum dataset allowable under the WFD guidance, but decreases rapidly when seven or more datapoints are available. Increasing the minimum number of ecotoxicity data in deriving an EQS results in a greater understanding of ecotoxicological effects. With this knowledge, the mitigating effects of water chemistry can be accounted for in deriving an EQS, even with relatively limited datasets. The new guidance suggests “simplistic” approaches to account for chemical availability, but does not detail how this might be undertaken. We provide examples of ways by which water chemistry effects can be included in deriving implementable EQS for metals with relatively few reliable and relevant data.     

Organochlorine and heavy metals in newborns: Results from the Flemish Environment and Health Survey (FLEHS 2002–2006)

To collect regional information on internal levels of pollutants in humans in Flanders, 1196 mother–child pairs were systematically recruited in 2002–2003 via 25 maternities across Flanders. Cd, Pb, PCB congeners 118, 170, 138, 153 and 180, p,p′-DDE — a key metabolite of DDT- and hexachlorobenzene (HCB) were measured in cord blood or plasma. Cd was detected in 64% of the samples (geometric mean 0.21 µg/L cord blood). p,p′-DDE (110 ng/g plasma lipids) and Pb (14.7 µg/L blood), were measurable in nearly all samples. The individual PCB congeners could be detected in 40 to 81% of the newborns (138 + 153 + 180 = 64.4 ng/g plasma lipids). HCB (18.9 ng/g plasma lipids) and dioxin-like compounds measured by DR-CALUX® (23 pg CALUX-TEQ/g lipids) were above detection limit in more than 75% of the samples. Age and smoking habits of the mothers, did not influence the cord blood Pb and Cd levels. The organochlorines increased 4 to 9% per year of the mother's age (partial R² = 0.05 to 0.22). Mothers had 2.6% less PCBs in cord blood (partial R² = 0.02) for each unit increase in pre-pregnancy BMI. Season of delivery, breastfeeding previous children or consumption of local dairy products, were minor determinants. Up to 20% of the variability in organochlorine concentrations was explained by residence area. It was concluded that the place of birth in Flanders is an important determinant of the load of pollutants measured at the start of life. This underlines the validity of human biomonitoring on (relatively) small geographical scale.