Scientific Opinion on Exploring options for providing advice about possible human health risks based on the concept of Threshold of Toxicological Concern (TTC)

<p>Synthetic and naturally occurring substances present in food and feed, together with their possible breakdown or reaction products, represent a large number of substances, many of which require risk assessment. EFSA’s Scientific Committee was requested to evaluate the threshold of toxicological concern (TTC) approach as a tool for providing scientific advice about possible human health risks from low level exposures, its applicability to EFSA’s work, and to advise on any additional data that might be needed to strengthen the underlying basis of the TTC approach. The Scientific Committee examined the published literature on the TTC approach, undertook its own analyses and commissioned an <em>in silico </em>investigation of the databases underpinning the TTC approach. The Scientific Committee concluded that the TTC approach can be recommended as a useful screening tool either for priority setting or for deciding whether exposure to a substance is so low that the probability of adverse health effects is low and that no further data are necessary. The following human exposure threshold values are sufficiently conservative to be used in EFSA’s work; 0.15 μg/person per day for substances with a structural alert for genotoxicity, 18 μg/person per day for organophosphate and carbamate substances with anti-cholinesterase activity, 90 μg/person per day for Cramer Class III and Cramer Class II substances, and 1800 μg/person per day for Cramer Class I substances, but for application to all groups in the population, these values should be expressed in terms of body weight, i.e. 0.0025, 0.3, 1.5 and 30 μg/kg body weight per day, respectively. Use of the TTC approach for infants under the age of 6 months, with immature metabolic and excretory systems, should be considered on a case-by-case basis. The Committee defined a number of exclusion categories of substances for which the TTC approach would not be used.</p&gt

Stormwater harvesting for irrigation purposes: An investigation of chemical quality of water recycled in pervious pavement system

Most available water resources in the world are used for agricultural irrigation. Whilst this level of water use is expected to increase due to rising world population and land use, available water resources are expected to become limited due to climate change and uneven rainfall distribution. Recycled stormwater has the potential to be used as an alternative source of irrigation water and part of sustainable water management strategy. This paper reports on a study to investigate whether a sustainable urban drainage system (SUDS) technique, known as the pervious pavements system (PPS) has the capability to recycle water that meets irrigation water quality standard. Furthermore, the experiment provided information on the impact of hydrocarbon (which was applied to simulate oil dripping from parked vehicles onto PPS), leaching of nutrients from different layers of the PPS and effects of nutrients (applied to enhance bioremediation) on the stormwater recycling efficiency of the PPS. A weekly dose of 6.23×10-3L of lubricating oil and single dose of 17.06g of polymer coated controlled-release fertilizer granules were applied to the series of 710mm×360mm model pervious pavement structure except the controls. Rainfall intensity of 7.4mm/h was applied to the test models at the rate of 3 events per week. Analysis of the recycled water showed that PPS has the capability to recycle stormwater to a quality that meets the chemical standards for use in agricultural irrigation irrespective of the type of sub-base used. There is a potential benefit of nutrient availability in recycled water for plants, but care should be taken not to dispose of this water in natural water courses as it might result in eutrophication problems. © 2014 Elsevier Ltd

Antibacterial and dermal toxicological profiles of ethyl acetate extract from Crassocephalum bauchiense (Hutch.) Milne-Redh (Asteraceae)

<p>Abstract</p> <p>Background</p> <p>The emergence in recent years of numerous resistant strains of pathogenic bacteria to a range of formerly efficient antibiotics constitutes a serious threat to public health. <it>Crassocephalum bauchiense</it>, a medicinal herb found in the West Region of Cameroon is used to treat gastrointestinal infections as well as liver disorders. The ethyl acetate extract from the leaves of <it>C. bauchiense </it>was evaluated for its antibacterial activity as well as acute and sub-acute toxicities.</p> <p>Methods</p> <p>The plant extract was prepared by maceration in ethyl acetate. Its phytochemical screening was done by standard methods. The broth microdilution method was used to evaluate the <it>in vitro </it>antibacterial activity. The <it>in vivo </it>antibacterial activity of a gel formulation (0.05, 1 and 2% w/v) of this extract was evaluated using a <it>Staphylococcus aureus</it>-induced dermatitis in a murine model. Selected haematological and biochemical parameters were used to evaluate the dermal sub-acute toxicity of the extract in rats.</p> <p>Results</p> <p>Phytochemical screening of the <it>C. bauchiense </it>extract revealed the presence of alkaloids, phenols, tannins and sterols. <it>In vitro </it>antibacterial activities were observed against all the tested microorganisms (MIC = 0.04-6.25 mg/ml). Formulated extract-gel (2% w/v) and gentamycin (reference drug) eradicated the microbial infection after five days of treatment. A single dermal dose of this extract up to 32 g/kg body weight (bw) did not produce any visible sign of toxicity. Also, daily dermal application of the <it>C. bauchiense </it>extract gel formulation for 28 days did not show any negative effect, instead some biochemical parameters such as alanine aminotransferase (ALT and AST), low density lipoprotein (LDL), high density lipoprotein (HDL) and triglycerides were significantly (p < 0.05) affected positively.</p> <p>Conclusion</p> <p>These results indicate that the <it>C. bauchiense </it>ethyl acetate extract can be used safely for the treatment of some bacterial infections.</p

Implementation of a Practice Development Model to Reduce the Wait for Autism Spectrum Diagnosis in Adults

This study examined waiting times for diagnostic assessment of Autism Spectrum Disorder in 11 adult services, prior to and following the implementation of a 12 month change program. Methods to support change are reported and a multi-level modelling approach determined the effect of the change program on overall wait times. Results were statistically significant (b = − 0.25, t(136) = − 2.88, p = 0.005). The average time individuals waited for diagnosis across all services reduced from 149.4 days prior to the change program and 119.5 days after it, with an average reduction of 29.9 days overall. This innovative intervention provides a promising framework for service improvement to reduce the wait for diagnostic assessment of ASD in adults across the range of spectrum presentations