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ABSTRACT: To assess the long-term clinical effectiveness and cost-effectiveness of multicomponent weight management schemes for adults in terms of weight loss and maintenance of weight loss.
Bibliographic databases were searched from inception to December 2009, including the Cochrane Library, MEDLINE (Ovid), EMBASE (Ovid), and MEDLINE In-Process & Other Non-Indexed Citations. Bibliographies of related papers were screened, key conferences and symposia were searched and experts were contacted to identify additional published and unpublished references.
For the clinical effectiveness review, two reviewers independently screened titles and abstracts for eligibility. Inclusion criteria were applied to the full text of retrieved papers by one reviewer and checked by a second reviewer using a pre-piloted inclusion flow chart. The studies were long-term randomised controlled trials (RCTs) of adult participants who were classified by body mass index as overweight or obese. Interventions were multicomponent weight management programmes (including diet, physical activity and behaviour change strategies) that assessed weight measures. Programmes that involved the use of over-the-counter medicines licensed in the UK were also eligible. For the cost-effectiveness review two reviewers independently screened studies for inclusion. Cost-effectiveness, cost-utility, cost-benefit or cost-consequence analyses were eligible. Data were extracted using a standardised and pre-piloted data extraction form. The quality of included studies was assessed using standard criteria. Studies were synthesised through a narrative review with full tabulation of results.
A total of 3358 references were identified, of which 12 were included in the clinical effectiveness review. Five RCTs compared multicomponent interventions with non-active comparator groups. In general, weight loss appeared to be greater in the intervention groups than in the comparator groups. Two RCTs compared multicomponent interventions that focused on the diet component. In these studies there were no statistically significant differences in weight loss between interventions. Four RCTs compared multicomponent interventions that focused on the physical activity component. There was little consistency in the pattern of results seen, in part owing to the differences in the interventions. In one RCT the intervention focused on the goal-setting interval and it appeared that weight loss was greatest in those given daily goals compared with weekly goals. Overall, where measured, it appeared that most groups began to regain weight at further follow-up. Of the 419 studies identified in the cost-effectiveness searches, none met the full inclusion criteria. Two economic evaluations are described in our review; however, caution is required in their interpretation, as they did not meet all inclusion criteria. Lifetime chronic disease models were used in these studies and the models included the costs and benefits of avoiding chronic illness. Both studies found the interventions to be cost-effective, with estimates varying between -£473 and £7200 (US$12,640) per quality-adjusted life-year gained; methodological omissions from these studies were apparent and caution is therefore required in the interpretation of these results.
Long-term multicomponent weight management interventions were generally shown to promote weight loss in overweight or obese adults. Weight changes were small however and weight regain was common. There were few similarities between the included studies; consequently an overall interpretation of the results was difficult to make. There is some evidence that weight management interventions are likely to be cost-effective, although caution is required as there were some limitations in the two cost-evaluation studies described.
The National Institute for Health Research Health Technology Assessment programme.
Health technology assessment (Winchester, England). 01/2011; 15(2):1-182.
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ABSTRACT: Recombinant human growth hormone (rhGH) is licensed for short stature associated with growth hormone deficiency (GHD), Turner syndrome (TS), Prader-Willi syndrome (PWS), chronic renal insufficiency (CRI), short stature homeobox-containing gene deficiency (SHOX-D) and being born small for gestational age (SGA).
To assess the clinical effectiveness and cost-effectiveness of rhGH compared with treatment strategies without rhGH for children with GHD, TS, PWS, CRI, SHOX-D and those born SGA.
The systematic review used a priori methods. Key databases were searched (e.g. MEDLINE, EMBASE, NHS Economic Evaluation Database and eight others) for relevant studies from their inception to June 2009. A decision-analytical model was developed to determine cost-effectiveness in the UK.
Two reviewers assessed titles and abstracts of studies identified by the search strategy, obtained the full text of relevant papers, and screened them against inclusion criteria. STUDY APPRAISAL: Data from included studies were extracted by one reviewer and checked by a second. Quality of included studies was assessed using standard criteria, applied by one reviewer and checked by a second. Clinical effectiveness studies were synthesised through a narrative review.
Twenty-eight randomised controlled trials (RCTs) in 34 publications were included in the systematic review. GHD: Children in the rhGH group grew 2.7 cm/year faster than untreated children and had a statistically significantly higher height standard deviation score (HtSDS) after 1 year: -2.3 ± 0.45 versus -2.8 ± 0.45. TS: In one study, treated girls grew 9.3 cm more than untreated girls. In a study of younger children, the difference was 7.6 cm after 2 years. HtSDS values were statistically significantly higher in treated girls. PWS: Infants receiving rhGH for 1 year grew significantly taller (6.2 cm more) than those untreated. Two studies reported a statistically significant difference in HtSDS in favour of rhGH. CRI: rhGH-treated children in a 1-year study grew an average of 3.6 cm more than untreated children. HtSDS was statistically significantly higher in treated children in two studies. SGA: Criteria were amended to include children of 3+ years with no catch-up growth, with no reference to mid-parental height. Only one of the RCTs used the licensed dose; the others used higher doses. Adult height (AH) was approximately 4 cm higher in rhGH-treated patients in the one study to report this outcome, and AH-gain SDS was also statistically significantly higher in this group. Mean HtSDS was higher in treated than untreated patients in four other studies (significant in two). SHOX-D: After 2 years' treatment, children were approximately 6 cm taller than the control group and HtSDS was statistically significantly higher in treated children. The incremental cost per quality adjusted life-year (QALY) estimates of rhGH compared with no treatment were: 23,196 pounds for GHD, 39,460 pounds for TS, 135,311 pounds for PWS, 39,273 pounds for CRI, 33,079 pounds for SGA and 40,531 pounds for SHOX-D. The probability of treatment of each of the conditions being cost-effective at 30,000 pounds was: 95% for GHD, 19% for TS, 1% for PWS, 16% for CRI, 38% for SGA and 15% for SHOX-D.
Generally poorly reported studies, some of short duration.
Statistically significantly larger HtSDS values were reported for rhGH-treated children with GHD, TS, PWS, CRI, SGA and SHOX-D. rhGH-treated children with PWS also showed statistically significant improvements in body composition measures. Only treatment of GHD would be considered cost-effective at a willingness-to-pay threshold of 20,000 to 30,000 pounds per QALY gained. This analysis suggests future research should include studies of longer than 2 years reporting near-final height or final adult height.
Health technology assessment (Winchester, England). 09/2010; 14(42):1-209, iii-iv.
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ABSTRACT: To assess the clinical and cost-effectiveness of magnesium sulphate compared with sotalol, and to assess the clinical effectiveness of magnesium sulphate compared with placebo in the prevention of atrial fibrillation (AF) in patients who have had a coronary artery bypass graft (CABG).
Major electronic databases were searched from December 2003 to May 2007.
Selected studies were assessed, subjected to data extraction using a standard template and quality assessment using published criteria. A simple short-term economic model was developed, informed by a systematic review of economic evaluations and populated with data from a review of costing/resource-use studies and other published studies. The cost-effectiveness of magnesium sulphate as prophylaxis was estimated for a set of base-case assumptions and the robustness of these results was assessed using deterministic and probabilistic sensitivity analysis.
Twenty-two papers met the inclusion criteria reporting 15 trials which all compared magnesium sulphate with placebo or control. They ranged in size from 15 to 176 patients randomised, and were conducted in Europe, the USA and Canada. The standard of reporting was generally poor, with details of key methodological attributes difficult to elucidate. No trials were identified that specifically aimed to compare magnesium sulphate with sotalol. Of 1070 patients in the pooled magnesium group, 230 (21%) developed postoperative AF, compared with 307 of 1031 (30%) patients in the placebo or (control) group. Meta-analysis using a fixed-effects model generated a pooled odds ratio (OR) that was significantly less than 1.0 [OR=0.65, 95% confidence interval (CI) 0.53 to 0.79, test for overall effect p<0.0001], but with statistically significant heterogeneity (I2=63.4%, p=0.0005). Two randomised controlled trials (RCTs) were notable as they had relatively lower ORs in favour of magnesium sulphate. When these were removed from the analyses the pooled OR remained statistically significant, but heterogeneity no longer remained significant. These two studies tended to impart a highly significant reduction in the odds of AF to whichever subgroup they were analysed in. When studies were ordered by total duration of prophylaxis, an apparent relationship between duration and odds of AF was evident, with decreasing odds of AF as duration of prophylaxis increased. This was confirmed by linear regression analysis (R2=0.743, p<0.001). When the data were grouped into three classes according to duration, a statistically significant intervention effect was only present for the longest duration (OR=0.12, 95% CI 0.06 to 0.23, p=0.00001). Statistically significant intervention effects were associated with the initiation of prophylaxis 12 hours or more before surgery (OR 0.26; 95% CI 0.16 to 0.44, test for overall effect p=0.00001, fixed-effects model) and less than 12 hours before surgery or during the surgery itself (OR=0.73, 95% CI 0.56 to 0.97, test for overall effect p = 0.03, fixed-effects model), but not when prophylaxis was initiated at the end of surgery or postsurgery (OR=0.85, 95% CI 0.59 to 1.22, p=0.37, fixed-effects model). When studies were ordered by total dose of intravenous magnesium sulphate (<25 g), the odds of AF were independent of the dose. A notable exception was that for a total dose of 9 g magnesium sulphate; here the odds of AF were significantly reduced relative to the control group, although this may be explained by the fact that these studies had excluded patients who were on antiarrhythmic drugs and so may have been at higher risk of AF. Sixty-three potentially relevant references about cost-effectiveness were identified, but no economic evaluations of intravenous magnesium alone as prophylaxis against AF following CABG, compared with sotalol as prophylaxis or no prophylaxis, were identified. Studies reporting resource use by patients with AF following CABG suggest that while AF significantly increased inpatient stays, by up to 2.3 days in the intensive care unit (ICU) and 3.4 days on the ward, differences in length of stay and costs between patients receiving prophylaxis and those not receiving prophylaxis were not statistically significant. In the base-case analysis, magnesium sulphate prophylaxis resulted in 0.081 fewer cases of AF at an incremental cost of 2.55 pounds sterling. The incremental cost-effectiveness ratio (ICER) was 32 pounds sterling per AF case avoided. The estimated difference in average length of stay between the prophylaxis and no-prophylaxis strategies was only 0.24 days, despite a large assumed difference of 3 days for patients experiencing AF in each group (1 extra day in the ICU and 2 extra days on the ward). In a deterministic sensitivity analysis the greatest variation in ICERs was observed for input parameters relating to the baseline risk of AF following CABG and the effectiveness of prophylaxis, cost of prophylaxis and the resource consequences of postoperative AF. The largest ICER (2092 pounds sterling) in the sensitivity analysis was associated with increasing the length of patients' preoperative stay. In the base case it was assumed that admission routines would be identical under both strategies. However, patients receiving prophylaxis by intravenous infusion may have longer preoperative stays. In a probabilistic analysis the majority of the simulations were associated with improved outcomes (in this case fewer cases of AF), but also higher costs. Prophylaxis was the dominant strategy (better outcome at lower cost) in about 41% of the simulations using the base-case assumptions. Under an alternative scenario where patients receiving prophylaxis are admitted for longer before their operation, to receive their initial infusion, the proportion of simulations where prophylaxis dominates fell to around 5%. The probability of being cost-effective was 99% at a willingness to pay (WTP) threshold of 2000 pounds sterling per AF case avoided and 100% at a WTP threshold of 5000 pounds sterling per AF case avoided under the base-case assumptions. Under the alternative scenario of longer preoperative stays the probability of being cost-effective at these two threshold values fell to 48% and 93%, respectively. It is unclear what the appropriate decision threshold should be, given that this model used intermediate rather than final outcomes.
No RCTs were identified that specifically aimed to compare intravenous magnesium with sotalol as prophylaxis for AF in patients undergoing CABG. Intravenous magnesium, compared with placebo or control, is effective in preventing postoperative AF, as confirmed by a statistically significant intervention effect based on pooled analysis of 15 RCTs. It was also found that AF was less likely to occur when a longer duration of prophylaxis was used, and the earlier that prophylaxis is started; however, this finding was associated with two RCTs that had more favourable results than the other trials. No clear relationship between dose and AF was observed, although a lower constant dose rate was associated with the lowest odds of AF. Further research should investigate the relationship between dose, dose rate, duration of prophylaxis, timing of initiation of therapy and patient characteristics, such as degree of risk for AF. This will provide stronger evidence for the optimum delivery of intravenous magnesium in patients undergoing CABG. In the base-case analysis in the economic model, magnesium sulphate prophylaxis reduced the number of postoperative AF cases at a modest increase in cost. The results of the economic analysis are highly sensitive to variation in certain key parameters. Prophylaxis is less likely to be a cost-effective option if it requires changes in admission routines that result in longer preoperative stays than would be the case without prophylaxis.
Health technology assessment (Winchester, England) 07/2008; 12(28):iii-iv, ix-95. · 4.26 Impact Factor
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J Shepherd,
G Rogers,
R Anderson,
C Main,
J Thompson-Coon,
D Hartwell,
Z Liu,
E Loveman,
C Green,
M Pitt,
K Stein,
P Harris, G K Frampton,
M Smith,
A Takeda,
A Price,
K Welch,
M Somerville
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ABSTRACT: To assess the clinical and cost-effectiveness of inhaled corticosteroids (ICS) alone and ICS used in combination with a long-acting beta2 agonist (LABA) in the treatment of chronic asthma in adults and children aged over 12 years.
Major electronic bibliographic databases, e.g. MEDLINE and EMBASE, were searched up to February/March 2006 (and updated again in October 2006).
A systematic review of clinical and cost-effectiveness studies was conducted. Cost comparison and cost-consequence analyses were performed where appropriate.
The assessment of clinical effectiveness was based on the 67 randomised controlled trials selected from the 5175 reports identified through the systematic literature search. The most frequently reported relevant outcomes were lung function, symptoms, use of rescue medication and adverse events. The trials varied considerably. In the trials that compared low-dose ICS versus ICS and high-dose ICS versus ICS, there were few significant differences in clinical effectiveness, although a few of the trials had assessed non-inferiority between the comparators rather than superiority. At doses of 400, 800 and 'high-level' doses of 1500 or 1600 microg/day, beclometasone dipropionate (BDP) appears to be the current cheapest ICS product both with the inclusion and exclusion of chlorofluorocarbon (CFC)-propelled products. A significant treatment benefit for combination ICS/LABA therapy across a range of outcomes compared with ICS alone was identified [when the ICS was double the accepted clinically equivalent dose of the ICS in the combination inhaler, and dry powder inhalers (DPIS) were used to deliver the drugs]. When a formoterol fumarate (FF)/salmeterol (SAL) combination inhaler and a budesonide (BUD)/FF combination inhaler were each compared with their constituent drugs delivered in separate inhalers, there were very few statistically significant differences between the treatments across the various efficacy outcomes and the rate of adverse events. Combination inhalers were more often cheaper than doubling the dose of ICS alone. However, the costs were highly variable and dependent on both the dose required and the preparation used in the trials. The estimated mean annual cost of FP/SAL combination varied from being 94 pounds cheaper to 109 pounds more expensive than the alternative of BUD at a higher dose. The BUD/FF combination varied from being 163 pounds cheaper to 66 pounds more expensive than the higher dose of either BUD or FP. When the combination inhalers were compared to each other, the results were mixed, with the FP/SAL combination significantly superior on some outcomes and the BUD/FF combination superior on others; however, meta-analysis showed that there were no significant differences between the two treatments in the rate of adverse events. Taking an ICS with a LABA as either of the two currently available combination products, FP/SAL and BUD/FF, is usually cheaper than taking the relevant constituent drugs in separate inhalers. At very high doses of BUD (1600 microg/day), however, the BUD/FF combination inhaler can be up to 156 pounds more expensive than having the same drugs in separate inhalers. In terms of the relative costs associated with taking one of the combination inhalers, at low dose (400 microg BUD or 200 microg FP/day) the cheapest combination inhaler is FP/SAL as a pressurised metered dose inhaler (pMDI) (Seretide Evohaler). However, this is only slightly cheaper than using BUD/FF as a DPI (Symbicort Turbohaler). At higher dose levels (800 microg BUD or 500 microg FP/day) FP/SAL as either pMDI aerosol (Seretide Evohaler) or a DPI (Seretide Accuhaler) is the cheapest combination product available, but again only slightly cheaper than the DPI BUD/FF combination (Symbicort Turbohaler). It should be highlighted, however, that the three head-to-head trials that compared the effects of FP/SAL with BUD/FF used the FP/SAL DPI combination inhaler, Seretide Accuhaler.
The evidence indicates that there are few consistent significant differences in effects between the five ICS licensed for use in adults and adolescents over the age of 12 years, at either low or high dose. On average, BDP products currently tend to be the cheapest ICS available and tend to remain so as the daily ICS dose required increases. There is evidence that the addition of a LABA to an ICS is potentially more clinically effective than doubling the dose of ICS alone, although consistent significant differences between the two treatment strategies are not observed for all outcome measures. The cost differences between combination therapy compared with ICS monotherapy are highly variable and dependent on the dose required and the particular preparations used. For the combination therapies of ICS/LABA there are potential cost savings with the use of combination inhalers compared with separate inhalers, with few differences between the two treatment strategies in terms of effects. The only exception to this cost saving is with BUD/FF at doses higher than 1200 microg/day, where separate inhaler devices can become equivalent to or cheaper than combination inhalers. Neither of the two combination inhalers (FP/SAL or BUD/FF) is consistently superior in terms of treatment effect. A comparison of the costs associated with each combination therapy indicates that at low dose FP/SAL delivered via a pMDI is currently the cheapest combination inhaler but only marginally cheaper than BUD/FF delivered as a DPI. At higher doses, both the FP/SAL combination inhalers (PMDI and DPI) are marginally cheaper than BUD/FF (DPI). Future trials of treatment for chronic asthma should standardise the way in which outcome measures are defined and measured, with a greater focus on patient-centred outcomes. For informing future cost-utility and cost-effectiveness analyses from a UK NHS perspective, there is a need for longitudinal studies that comprehensively track the care pathways followed when people experience asthma exacerbations of different severity. Further research synthesis, quantifying the adverse effects of the different ICS, is required for treatment choices by patients and clinicians to be fully informed.
Health technology assessment (Winchester, England) 06/2008; 12(19):iii-iv, 1-360. · 4.26 Impact Factor
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ABSTRACT: To examine the clinical effectiveness of patient education models for adults with Type 2 diabetes.
Electronic databases were searched from 2002 to January 2007.
A systematic review of the literature on educational interventions in diabetes was undertaken. This was an update of a previous systematic review.
Including studies identified in the previous systematic review, there were 13 published studies. Eight studies of education on multiple aspects of diabetes self-management were identified that provided education that was focused on a particular aspect of self-management. The quality of reporting and methodology of the studies was variable. Studies of multi-component educational interventions yielded mixed results. Some trials reported significant improvements on measures of diabetic control but others did not. Positive effects may be attributable to longer-term interventions with a shorter duration between the end of the intervention and the follow-up evaluation point. There may also be an effect of having a multi-professional team delivering the educational programme. Studies of focused educational interventions did not yield consistent results. Some effects were shown on measures of diabetic control in studies that focused on diet or exercise alone. Although the effects shown were generally small, those that were present did appear to be relatively long-lasting. This update review does not substantially alter the conclusions of the previous systematic review; for each outcome, the proportion of studies that demonstrated significant effects of education was similar.
Based on the evidence, it would seem that education delivered by a team of educators, with some degree of reinforcement of that education made at additional points of contact, may provide the best opportunity for improvements in patient outcomes. Educators need to have time and resources to fulfil the needs of any structured educational programme. There is also a need for education to have a clear programme at the outset. From the evidence reported it is unclear what resources would need to be directed at the educators themselves to ensure that they can deliver programmes successfully. Any future research should consider patient education within the context of overall diabetes care and as such follow guidelines for the development and evaluation of complex interventions. Good-quality, longer-term studies would be desirable, but these would require careful consideration around the nature of any control group. Information is needed to clarify the sensitivity of diabetes education programmes to the performance of the diabetes educators, in order to ensure success and cost-effectiveness of education programmes.
Health technology assessment (Winchester, England) 05/2008; 12(9):1-116, iii. · 4.26 Impact Factor
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Analytical and Bioanalytical Chemistry 03/2007; 387(4):1167-72. · 3.78 Impact Factor
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ABSTRACT: The presence of human and veterinary pharmaceuticals in the environment has caused increasing concern due their effects on ecological receptors. Improving the risk assessment of these compounds necessitates a quantitative understanding of their metabolism and elimination in the target organism (toxicokinetics), particularly via the ubiquitous cytochrome P-450 (CYP) system and their mechanisms of toxicity (toxicodynamics). This review focuses on a number of pharmaceuticals and veterinary medicines of environmental concern, and the differences and similarities between ecological and human risk assessment. CYP metabolism is discussed with particular reference to its ubiquity in species of ecological relevance. The important issue of pharmaceutical mixtures is discussed to assess how emerging technologies such as ecotoxicogenomics may assist in moving towards a more mechanism-based environmental risk assessment of pharmaceuticals.
Analytical and Bioanalytical Chemistry 03/2007; 387(4):1259-68. · 3.78 Impact Factor
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ABSTRACT: Foliar sprays of the systemic fungicides carbendazim, propiconazole, and triadimenol were applied in summer to replicated barrier-enclosed and open plots in a field of winter wheat in southern England at dose rates equivalent to label recommendations. Surface-active Collembola (springtails) were sampled from the experimental plots by suction sampling and pitfall trapping before and after the fungicide applications. No consistent effects of the fungicides on collembolan activity were detected using pitfall trapping but suction sampling revealed a transient negative effect of propiconazole and triadimenol on the overall abundance of higher collembolan taxa. Among individual species, however, fungicide effects varied spatially. Fewer significant treatment effects were obtained in enclosed than in open plots and no consistent effects of carbendazim were detected. The relevance of these findings to current fungicide usage strategies in British arable crops, which include the use of complex tank mixes, is discussed.
Ecotoxicology and Environmental Safety 06/2000; 46(1):64-72. · 2.29 Impact Factor
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The Canadian Entomologist 01/1996; 128:1115-1124. · 0.85 Impact Factor
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ABSTRACT: Arable production has come under increasing economic and environmental pressures, especially in the last decade. These have derived from over-production, decreased farm incomes and a concern with the possible environmental effects of intensive pesticide use associated with such intensive cultivation. A number of long-term research programmes on integrated farming systems and their sustainability have recently been completed or are currently under way. In the UK, these include the ‘Boxworth’ project, ‘SCARAB’, TALISMAN’, RISC, ‘LINK Integrated Farming Systems’, ‘LIFE’ and the demonstration-only programme ‘LEAF’. These projects are reviewed in terms of their objectives, designs and results to date, and are compared with some parallel programmes in Germany, the Netherlands, Switzerland and France.
Annals of Applied Biology 09/1994; 125(2):399 - 438. · 2.18 Impact Factor
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In: J.M. Holland (ed.), The agroecology of carabid beetles. Andover (UK), Intercept, 2002, pp. 251-277.
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Pedobiologia 46 (2002), 3/4: 328-337.
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ABSTRACT: Non-target effects on terrestrial arthropod communities of the broad-spectrum insecticides chlorpyrifos and cypermethrin and the selective insecticide pirimicarb were investigated in winter wheat fields in summer. Effects of chlorpyrifos on arthropod abundance and taxonomic richness were consistently negative whereas effects of cypermethrin were negative for predatory arthropods but positive for soil surface Collembola. Pirimicarb effects were marginal, primarily on aphids and their antagonists, with no effect on the Collembola community. Collembola-predator ratios were significantly higher following cypermethrin treatment, suggesting that cypermethrin-induced increases in collembolan abundance represent a classical resurgence. Observations in other studies suggest Collembola resurgences may be typical after synthetic pyrethroid applications. Collembola responses to insecticides differed among species, both in terms of effect magnitude and persistence, suggesting that coarse taxonomic monitoring would not adequately detect pesticide risks. These findings have implications for pesticide risk assessments and for the selection of indicator species.
Environmental Pollution 147 (2007) 1.
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ABSTRACT: Previous work has identified two patterns of arthropod recovery after insecticide applications to arable crops: dispersal-mediated recolonisation from untreated areas (Type A) and recolonisation within treated areas assisted by reduced predation (Type B). In this study, connectivity between field-edge habitats was manipulated using barriers to investigate whether a crop edge and adjacent hedgerow influence recolonisation of an insecticide-treated crop by surface-active Collembola and other arthropods. Collembola recovery patterns differed among closely-related taxa. Epigeic collembolan and macroarthropod communities were more diverse and abundant, and rates of artificial prey predation were higher, in sprayed crop areas connected to both hedgerow and unsprayed crop edge than in sprayed areas connected to the unsprayed edge alone. These findings indicate that effectiveness of unsprayed crop edges as sources of field recolonisation may depend on adjoining field margin habitats. An assumption in risk assessment that unsprayed crop edges assist population recovery within treated areas is not supported.
Environmental Pollution 145 (2007) 3.
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ABSTRACT: Species sensitivity distributions (SSD) and 5% hazardous concentrations (HC5) are distribution-based approaches for assessing environmental risks of pollutants. These methods have potential for application in pesticide risk assessments, but their applicability for assessing pesticide risks to soil invertebrate communities has not been evaluated. Using data obtained in a systematic review, the present study investigates the relevance of SSD and HC5 for predicting pesticide risks to soil invertebrates. Altogether, 1,950 laboratory toxicity data were obtained, representing 250 pesticides and 67 invertebrate taxa. The majority (96%) of pesticides have toxicity data for fewer than five species. Based on a minimum of five species, the best available endpoint data (acute mortality median lethal concentration) enabled SSD and HC5 to be calculated for 11 pesticides (atrazine, carbendazim, chlorpyrifos, copper compounds, diazinon, dimethoate, ¿-hexachlorocyclohexane, lambda-cyhalothrin, parathion, pentachlorophenol, and propoxur). Arthropods and oligochaetes exhibit pronounced differences in their sensitivity to most of these pesticides. The standard test earthworm species, Eisenia fetida sensu lato, is the species that is least sensitive to insecticides based on acute mortality, whereas the standard Collembola test species, Folsomia candida, is among the most sensitive species for a broad range of toxic modes of action (biocide, fungicide, herbicide, and insecticide). These findings suggest that soil arthropods should be tested routinely in regulatory risk assessments. In addition, the data indicate that the uncertainty factor for earthworm acute mortality tests (i.e., 10) does not fully cover the range of earthworm species sensitivities and that acute mortality tests would not provide the most sensitive risk estimate for earthworms in the majority (95%) of cases.
Environmental Toxicology and Chemistry 25 (2006) 9.
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ABSTRACT: A systematic review was carried out to investigate the extent to which higher-tier (terrestrial model ecosystem [TME] and field) data regarding pesticide effects can be compared with laboratory toxicity data for soil invertebrates. Data in the public domain yielded 970 toxicity endpoint data sets, representing 71 pesticides and 42 soil invertebrate species or groups. For most pesticides, the most frequent effect class was for no observed effects, although relatively high numbers of pronounced and persistent effects occurred when Lumbricidae and Enchytraeidae were exposed to fungicides and when Lumbricidae, Collembola, and Arachnida were exposed to insecticides. No effects of fungicides on Arachnida, Formicidae, or Nematoda or of herbicides on Lumbricidae, Formicidae, or Nematoda were observed in any studies. For most pesticides, higher-tier no-observed-effect concentration or lowest-observed-effect concentration values cannot be determined because of a lack of information at low pesticide concentrations. Ten pesticides had sufficient laboratory data to enable the observed higher-tier effects to be compared with 5% hazardous concentrations (HC5) estimated from acute toxicity laboratory data (atrazine, carbendazim, chlorpyrifos, diazinon, dimethoate, ¿-hexachlorocyclohexane, lambda-cyhalothrin, parathion, pentachlorophenol, and propoxur). In eight cases, higher-tier effects concentrations were within or below the 90% confidence interval of the HC5. Good agreement exists between the results of TME and field tests for carbendazim, but insufficient information is available for a comparison between TME and field studies for other pesticides. Availability and characteristics (e.g., taxonomic composition and heterogeneity) of the higher-tier effects data are discussed in terms of possible developments in risk assessment procedures.
Environmental Toxicology and Chemistry 25 (2006) 9.
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J. appl. Ecol. 37 (2000): 865-883.
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Appl. Soil Ecol. 14 (2000): 231-248.
