Irish moss—from an art to an industry

This red alga, harvested commercially along the shores of Prince Edward Island, Nova Scotia and New England, is today processed by five American companies into an extractive that finds a major market as a stabilizer in dairy products and enters also into the manufacture of a variety of other products ranging from beer to toothpaste.     

The Aquatic Environment and Textile Mill Effluents — An Ecological Risk Assessment

Textile mill effluents (TMEs) are wastewater discharges from textile mills that are involved in wet processes such as scouring, neutralizing, desizing, mercerizing, carbonizing, fulling, bleaching, dyeing, printing and other wet finishing activities. TMEs are complex mixtures containing a wide variety of chemicals which have a range of pH, temperature, colour and oxygen demand characteristics. Most wet processing mills in Canada discharge to municipal wastewater collection systems where those effluents receive some form of wastewater treatment. This paper reports the results of a tiered assessment approach that was used to determine the impacts on the aquatic environment of whole effluents discharged by wet processing textile mills in Canada. A conservative assessment indicated that no substantial threat to the aquatic environment was associated with TMEs receiving secondary or tertiary treatment, on- site or at a municipal wastewater treatment plant, prior to discharge to receiving waters. In the case of TMEs receiving only primary treatment or no treatment prior to discharge, a weight-of-evidence risk assessment supported the conclusion that those effluents could produce significant environmental harm in aquatic environments.     

Soil Microbial Communities and Ecological Risk Assessment: Risk Assessors’ Perspective

In the past, ecological risk assessments (ERAs) have generally overlooked the soil microbial community when evaluating the impacts of contaminants in soil. However, the soil microbial community, which includes bacteria and fungi, performs functions necessary for overall ecosystem health, including nitrogen fixation, nutrient cycling, and even degradation of contaminants. The incorporation of the soil microbial community into ERA requires the compilation of adequate toxicity data to complete the hazard assessment phase of the risk assessment. A variety of soil microbial toxicity tests exist that provide rapid and inexpensive results. Surveys of the microbial community at a contaminated site may also provide insight as to their functioning in the presence of contaminants. This paper explores the use of toxicity tests and surveys to evaluate chemical toxicity to microbes. However, many questions related to the best methodological approach to an ERA of the soil microbial community have yet to be answered.     

Improving the Applicability of Quantitative Ecological Risk Assessment Tools—Understanding Demand-Side Changes

Quantitative ecological risk assessment (ERA) methods are the tools of choice for many natural resource management agencies and practitioners. However, a number of researchers and practitioners have recently highlighted that the application of quantitative ERA tools has perhaps been somewhat limited and this has stimulated discussion on the limitations of these methods, considered to be supply-side limitations in this analysis. By contrast, it is argued here that the demand for risk assessment tools has also changed substantively and this also acts to limit the use of ERA approaches. In particular, demand has changed through an increasing expectation that quantitative ERA tools will be able to capture ecosystem-scale, and sometimes global-scale interactions to support ecosystem-based management approaches. Similarly, the burgeoning use of market-based policy instruments often underpinned by the allocation of private property rights to an increasing number of ecosystem goods and services has fundamentally changed many natural resource management issues into allocation conflicts between alternate rights-holders. These demand-side changes represent both an opportunity and a challenge for developers of quantitative ERA tools.     

Leukocyte Adhesion—an Integrated Molecular Process at the Leukocyte Plasma Membrane

Leukocyte adhesion is of pivotal functional importance, because most leukocyte functions depend on cell–cell contact. It must be strictly controlled, both at the level of specificity and strength of interaction, and therefore several molecular systems are involved. The most important leukocyte adhesion molecules are the selectins, the leukocyte-specific ₂-integrins and the intercellular adhesion molecules. The selectins induce an initial weak contact between cells, whereas firm adhesion is achieved through integrin–intercellular adhesion molecular binding. Although studies during the past twenty years have revealed several important features of leukocyte adhesion much is still poorly understood, and further work dealing with several aspects of adhesion is urgently needed. In this short essay, we review some recent developments in the field.     

Testing and Risk Assessment of Persistent and Bioaccumulating Chemical Substances—Improvements within REACH?

In the proposed new European chemicals regulations—the REACH system—the improved control of persistent and bioaccumulating substances is stated as one of the tasks being of particular importance. In this article, the reliability and validity of the scientific basis for identification of persistent (P), bioaccumulating (B), and toxic (T) substances, and for assessing the risks that these substances may pose, are discussed. We have used the European Union risk assessment of pentabromodiphenyl ether, PentaBDE (CAS 32534-81-9) as a study case in the analysis. It is concluded that for PBT substances there is room for development both with regard to test methodology and with regard to risk assessment procedures.     

Repeat Cardiovascular Risk Assessment after Four Years: Is There Improvement in Risk Prediction?

Background

Framingham risk equations are widely used to predict cardiovascular disease based on health information from a single time point. Little is known regarding use of information from repeat risk assessments and temporal change in estimated cardiovascular risk for prediction of future cardiovascular events. This study was aimed to compare the discrimination and risk reclassification of approaches using estimated cardiovascular risk at single and repeat risk assessments

Methods

Using data on 12,197 individuals enrolled in EPIC-Norfolk cohort, with 12 years of follow-up, we examined rates of cardiovascular events by levels of estimated absolute risk (Framingham risk score) at the first and second health examination four years later. We calculated the area under the receiver operating characteristic curve (aROC) and risk reclassification, comparing approaches using information from single and repeat risk assessments (i.e., estimated risk at different time points).

Results

The mean Framingham risk score increased from 15.5% to 17.5% over a mean of 3.7 years from the first to second health examination. Individuals with high estimated risk (≥20%) at both health examinations had considerably higher rates of cardiovascular events than those who remained in the lowest risk category (<10%) in both health examinations (34.0 [95%CI 31.7–36.6] and 2.7 [2.2–3.3] per 1,000 person-years respectively). Using information from the most up-to-date risk assessment resulted in a small non-significant change in risk classification over the previous risk assessment (net reclassification improvement of -4.8%, p>0.05). Using information from both risk assessments slightly improved discrimination compared to information from a single risk assessment (aROC 0.76 and 0.75 respectively, p<0.001).

Conclusions

Using information from repeat risk assessments over a period of four years modestly improved prediction, compared to using data from a single risk assessment. However, this approach did not improve risk classification.     

Trgrps — an interactive algorithm for group recogniton with an example from spartinetea

Summary TRGRPS can detect groups or signal if discrete groups cannot be found in a sample. The present paper elaborates on the concepts, describes the algorithm and provides illustrations from syntaxonomy. A computer program (TRGRPS.BAS) is available from the author upon request.Contribution from the Working Group for Data Processing in Phytosociology, International Society for Vegetation Science. For nomenclature of species see Lausi, Beeftink & Kortekaas (1975).The research project, from which this paper summarizes partial results, is supported by a National Research Council of Canada grant. Computer time was provided by the University of Western Ontario.     

The 3MRA Risk Assessment Framework—A Flexible Approach for Performing Multimedia,Multipathway, and Multireceptor Risk Assessments Under Uncertainty

A flexible framework for conducting nationwide multimedia, multipathway and multireceptor risk assessments (3MRA) under uncertainty was developed to estimate protective chemical concentration limits in a source area. The framework consists of two components: risk assessment and uncertainty analysis. The risk component utilizes linked source, fate/transport, exposure and risk assessment models to estimate the risk exposures for the receptors of concern. Both human and ecological receptors are included in the risk assessment framework. The flexibility of the framework is based on its ability to address problems varying in spatial scales from site-specific to regional and even national levels; and its ability to accommodate varying types of source, fate/transport, exposure and risk assessment models. The uncertainty component of the 3MRA framework is based on a two-stage Monte Carlo methodology. It allows the calculation of uncertainty in risk estimates, and the incorporation of the effects of uncertainty on the determination of regulatory concentration limits as a function of variability and uncertainty in input data, as well as potential errors in fate and transport and risk and exposure models. The framework can be adapted to handle a wide range of multimedia risk assessment problems. Two examples are presented to illustrate its use, and to demonstrate how regulatory decisions can be structured to incorporate the uncertainty in risk estimates.     

Human Health Risk Assessment of Naturally Occurring Radioactive Materials in Produced Water—A Case Study

Human health effects from naturally occurring radioactive materials (NORM) in produced water are of concern due to their bioavailability and bioaccumulation characteristics in finfish and shellfish species used for human consumption. Being chemically similar to calcium, radium concentrates mostly in bones, shells, and exoskeletons. Previous studies have been based on the whole-body bioaccumulation of radium in fish where the distribution of radium in bone/exoskeleton and the edible parts of fish were not considered separately and thus the predicted risks were relatively high. In this article, the distribution of radium in the non-edible and edible parts of fish and the probability of exposure to a produced water plume have been studied in order to characterize human health risks. A probabilistic hydrodynamic model has been incorporated in this study. Using the concentration distribution approach, the mean cancer risks to humans were predicted in the range of 8.6 × 10^?7 to 9.5 × 10^?7, which were 2.6 to 2.7 times less than the risks predicted by using the whole body concentrations. The exceedence probability of maximum permissible human health cancer risk of 1 × 10^?4 is close to zero. At a risk level of 1 × 10^?6, the exceedence probability is 21% whereas in the whole body concentration approach it is between 45 to 49%. In this study, no effect on fish from exposure to NORM components in produced water was found.     

Characterization of an acid phosphatase—Glycoprotein from barley seeds

• 1.1. An acid phosphatase from barley seeds germinated for 120 hr, that is not affected by the presence of cycloheximide, is a glycoprotein.
• 2.2. The enzyme has an optimum pH 4.9 and a mol. wt of 57,000 as determined by SDS-gel electrophesis.
• 3.3. The main sugar is galactose amounting to one half of the protein and it is as either mono or disaccharide.
• 4.4. Serine and glycine predominate and hydroxyproline is absent.

     

Fusarium toxins in cereals — Results from eight German Federals States in 2000

A total of 353 cereal samples from 8 German Federal States were analysed for Fusarium toxins in the 2000' survey. The level of mycotoxin contamination of the samples was higher than in the previous year due to higher moisture during flowering in some regions. Concerning deoxynivalenol (DON), the prevailing mycotoxin in all the samples, we have to consider, that 24% of the samples as well as the average concentration exceed the advisory level of 500 μg/kg. The application of Fusarium active fungicides reduced the DON level from 963 μg/kg (samples without treatment) to 630 μg/kg (all samples from treated and untreated fields). It has to be emphasised that the number of nivalenol (NIV) positive samples increased in comparison to the previous year from 9% to 17%. In addition, an increase in the level of NIV was detected, the maximum concentration in winter wheat was 3480 μg/kg. Cereals were rather moderately contaminated with zearalenone (ZEA), more than 80% of the samples contained less than 50 μg/kg.     

Is There a Role for Risk Assessment within Precautionary Legislation?

Posing the question of whether the precautionary principle has a role in risk assessment effectively constrains any debate of the issue within a framework predicated on the assumption that application of risk assessment is inevitable in the formulation of regulatory decisions. The question can equally validly be expressed in terms of whether there is a role for risk assessment in the formulation of precautionary legislation. This allows the debate then to turn on consideration of two questions: Firstly, does the precautionary principle have a role in policy development? and secondly, is this role consistent and compatible with a risk based approach to regulation? When recast in these terms, a more holistic comparison of the aims and objectives of both approaches and of their relative power in the formulation of regulation becomes possible. This leads to the conclusion that the precautionary principle is, when defined and applied correctly, scientifically more robust than risk assessment. Precautionary approaches utilize scientific information and conform robustly to a scientific process but also explicitly incorporate indeterminacies into the decision making framework. Moreover, the precautionary principle when applied to environmental regulation, is more likely to lead to regulation consistent with global sustainability. On this premise, this paper argues that risk based approaches are essentially incompatible with approaches based on the precautionary paradigm, and that of the two, risk assessment is more likely to lead to unsustainable underprotection of the environment.     

Aspirin Use and Lung Cancer Risk: A Possible Relationship? Evidence from an Updated Meta-Analysis

Background and Purpose

Growing evidence has emerged and controversial results reported on possible relationship between aspirin use and lung cancer risk. We, therefore, conducted this updated and comprehensive meta-analysis to evaluate this issue, with focus on dose-risk and duration-risk relationships.

Methods

We searched electronic databases including PUBMED, EMBASE and Cochrane library to identify eligible studies. Relative risk (RR) and its 95% confidence interval (CI) were used for cohort studies, while odds ratio (OR) were employed for case-control studies. The random effects and fixed effects models were used for analyses.

Results

18 studies were identified including 19835 lung cancer cases, which were eligible for inclusion in the present meta-analysis. Pooled data from case-control studies showed a significant inverse association between regular aspirin use and lung cancer risk. But for cohort studies, insignificant association was detected with little evidence of heterogeneity (RR: 1.05, 95%CI: 0.95 – 1.16; I²: 10.3%, p value: 0.351). In case-control studies, standard aspirin use (>325mg) was related to lower lung cancer incidence, compared with low-dose aspirin use (75–100mg). A similar trend was observed in cohort studies. Besides, when analysis was restricted to long time regular aspirin use (>5 years), insignificant results were reported in both cohort and case-control studies. Finally, regular aspirin use might result in higher reduction of non-small cell lung cancer incidence among men.

Conclusions

Our findings do not support the protective effect of regular aspirin use on lung cancer risk. Long time aspirin use, sex, dose and type of lung cancer might alter the effect of aspirin use on lung cancer risk. More well-designed studies are needed to further clarify these associations.