An evaluation of contaminated estuarine sites using sediment quality guidelines and ecological assessment methodologies

Toxic contaminants may enter estuarine ecosystems through a variety of pathways. When sediment contaminant levels become sufficiently high, they may impact resident biota. One approach to predict sediment-associated toxicity in estuarine ecosystems involves the use of sediment quality guidelines (ERMs, ERLs) and site-specific contaminant chemistry while a second approach utilizes site-specific ecological sampling to assess impacts at the population or community level. The goal of this study was to utilize an integrated approach including chemical contaminant analysis, sediment quality guidelines and grass shrimp population monitoring to evaluate the impact of contaminants from industrial sources. Three impacted sites and one reference site were selected for study. Grass shrimp populations were sampled using a push-netting approach. Sediment samples were collected at each site and analyzed for metals, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and pesticides. Contaminant levels were then compared to sediment quality guidelines. In general, grass shrimp population densities at the sites decreased as the ERM quotients increased. Grass shrimp densities were significantly reduced at the impacted site that had an ERM exceedance for chromium and the highest Mean ERM quotient. Regression analysis indicated that sediment chromium concentrations were negatively correlated with grass shrimp density. Grass shrimp size was reduced at two sites with intermediate levels of contamination. These findings support the use of both sediment quality guidelines and site-specific population monitoring to evaluate the impacts of sediment-associated contaminants in estuarine systems.     

Canadian water quality guidelines for deltamethrin

Canadian Water Quality Guidelines (CWQG) are numerical or narrative limits that protect designated water uses. Development of CWQG is based on review of deltamethrin's properties, uses, fate in the environment, ambient levels, accumulation in biota, and toxicity. Deltamethrin is a synthetic pyrethroid insecticide used against agricultural pests. Concentrations of deltamethrin in Canadian agricultural areas range between 10 and 1000 ng m⁻³ in air, 0.04 and 24.0 μg L⁻¹ in water, 3 and 5 ng g⁻¹ in sediments, 281 and 1375 ng g⁻¹ in plants, and 3.0 and 50.0 ng g⁻¹ in animals. In nature, deltamethrin can undergo volatilization, isomerization, and hydrolysis. Estimates of toxicity of deltamethrin to freshwater life range from 0.0001 μg L⁻¹ (48- and 96-h EC₀ for immobilization of Daphnia magna) to 1700 mg L⁻¹ (EC₅₀ for photoinhibition of Selanastrum capricornutum). Terrestrial life is affected by concentrations of deltamethrin ranging from 1.0 mg kg⁻¹ (retardation of fetus development in mice) to 5000 mg kg⁻¹ (LD₅₀ for a rat). A full guideline of 0.4 μg L⁻¹ is recommended for the protection of freshwater life. A full guideline of 2.5 μg L⁻¹ is recommended for water used for livestock production. There were insufficient data to derive guidelines for recreation, irrigation, and industrial applications. © 1998 John Wiley & Sons, Inc. Environ Toxicol Water Qual 13: 175–210, 1998     

Comparisons between microscale and whole-sediment assays for freshwater sediment toxicity assessment

The use of several microscale assays for evaluating freshwater sediment toxicity was investigated to develop a representative and cost-effective test battery. The bioassays evaluated (18 assays total) included microscale assays performed on solid-phase, pore water, and organic extracts as well as conventional standardized whole-sediment assays with Chironomus riparius and Hyalella azteca on 10 sediment samples collected in the St. Lawrence/Great Lakes system. Selected sediment physical and chemical characteristics were also conducted to aid in the interpretation of results. Benthic invertebrate assays such as C. riparius and H. azteca endpoints were found to correlate well to contaminant levels. Microscale assays such as ATP (adenosine triphosphate) measurement of sediment microbial biomass gave promising results to predict whole-sediment toxicity to benthic invertebrates. Most assays on pore water did not adequately represent whole-sediment toxicity, whereas organic extracts appeared to be more representative, alleviating some potential confounding factors such as interference due to toxicity caused by ammonia. © 1998 John Wiley & Sons, Inc. Environ Toxicol Water Qual 13 : 93–110, 1998     

Application of a sediment quality triad and different statistical approaches (Hasse diagrams and fuzzy logic) for the comparative evaluation of small streams

In order to evaluate the ecotoxicological contamination of 12 aquatic sites in streams within the catch ment area of the Neckar River, a sediment quality triad (SQT) approach was applied. In contrast to Chapman's original triad approach, not only sediments, but also surface waters were examined. In brief, to obtain a com prehensive insight into the potential ecotoxicological hazard, both acute toxicity and more specific effects such as mutagenic, genotoxic, teratogenic, dioxin- and estrogen-like responses were recorded. Different statistical methods (ranking, cluster analyses, Hasse diagram techniques, and fuzzy logic) for the evaluation and presentation of the SQT data were compared with respect to the needs of environmental decision-making. Results document advan tages and disadvantages of the methods applied for the evaluation and classification of data within the complex data matrixes. The ranking procedure presented as well as the Hasse diagram technique seem to be suitable tools to elucidate the pattern of the ecotoxicological load. However, these classification methods require expert knowledge to interpret the ranking results with respect to decision-making in environmental sciences and policy. In contrast, fuzzy logic allows both to develop site-specific expert systems in order to assess the ecotoxicological burden and to give insight into the pattern of the contamination.     

手性药物研发进展与相关指导原则介绍

随着对手性药物认识的不断深入,不对称合成技术、拆分技术的飞速发展以及手性药物监管政策的日益完善,手性药物已成为新化学实体研发的重要方向。从手性药物的发展情况、手性药物的药理,毒理学特点,各国药品监管部门针对手性药物开发所颁布的指导原则的进展情况与我国手性药物安全性评价的现状几个方面进行综述总结,为手性药物的开发及其毒理学评价提供参考。     

Canadian water quality guidelines for glycols–An ecotoxicological review of glycols and associated aircraft anti-icing and deicing fluids

This paper reviews the environmental fate, chemistry and toxicology of ethylene, propylene, and diethylene glycol, and their associated aircraft deicing/anti-icing fluids. Ethylene glycol is currently the most prevalent glycol in Canada with high volume production and primary uses in deicing fluid and antifreeze mixtures and minor uses in polyester manufacturing. Propylene glycol use in Canada is concentrated in resin and polyester production whereas diethylene glycol is primarily used as a dehydrator in the natural gas industry. Glycols are miscible in water, and have very low log K_ow, and log K_oc values, which make these substances highly mobile. Aerobic biodegradation is the most important environmental fate process affecting glycols in waters and soils with available information demonstrating low persistence. Canadian monitoring data is limited to ethylene glycol where it has been routinely detected in stormwater runoff at airports. Glycols have relatively low aquatic toxicity, with algae being more sensitive than vertebrates or invertebrates. The most sensitive response recorded for ethylene glycol exposure was a 96-h LOEC of 1923.4 mg L⁻¹ for the green alga Selenastrum capricornutum. Aircraft deicing/anti-icing fluids were more toxic than pure glycols. The most sensitive recorded response was a 96-h LC₅₀ of 18 mg L⁻¹ for the fathead minnow Pimephales promelas, following exposure to a propylene glycol based anti-icing fluid. The review details the development and derivation of the Canadian Water Quality Guidelines for glycols, including numerical concentrations for the protection of aquatic life. ©1999 John Wiley & Sons, Inc. Environ Toxicol 14: 481–522, 1999     

Field evaluation of a rapid portable test for monitoring fecal coliforms in coastal waters

Two hundred beachwater samples were collected along the New South Wales coast, Australia, and analyzed for fecal coliforms in the field using a portable, 60 min fluorimetric assay of β-D -galactosidase activity. The aim of the study was to evaluate the reliability of the technique alongside a standard membrane filtration procedure to assess fecal contamination of coastal bathing waters. The assay had a 98% success rate at predicting whether the coliform concentrations of the samples were greater than, or less than, 300 fecal coliforms per 100 ml (the current limit of detection of the method). The results over which the two methods were in disagreement comprised less than 2% false positives [where the rapid method indicated greater than and membrane filtration indicated less than 300 colony-forming units (cfu) per 100 ml] and no false negatives (where the rapid method indicated less than and membrane filtration indicated greater than 300 cfu per 100 ml). The described assay provides a rapid, simple, and inexpensive method for the detection of fecal contamination in marine waters. As analyses can be performed in the field, the technique offers great potential for near real-time monitoring of water quality and as an “early warning” system for contamination of bathing waters. ©1999 John Wiley & Sons, Inc. Environ Toxicol 14: 355–359, 1999     

A caridean grass shrimp (Palaemonetes pugio Holthius) as an indicator of sediment quality in Florida coastal areas affected by point and nonpoint source contamination

Grass shrimp are one of the more widely distributed estuarine benthic organisms along the Gulf of Mexico and Atlantic coasts, but they were used infrequently in contaminated sediment assessments. Early‐life stages of caridean grass shrimp, Palaemonetes pugio (Holthius), were used in this baseline survey as indicators of sediment pore water quality for several Florida coastal areas affected by nonpoint and point sources of contamination. Static toxicity tests were conducted using 24 well culture plates assessing embryo and larval survival after 12 days exposure to pore water (interstitial water). Acute toxicity was observed in 28% of pore waters (15 of 53 samples) suggesting that sediment contamination was not widespread in the study area based on the response of this species. When toxicity was observed, grass shrimp pore water toxicity test was usually a more sensitive indicator of contamination than solid‐phase tests conducted with the epibenthic invertebrate, Mysidopsis bahia. P. pugio embryos were more sensitive than larval form and response of different brood stocks usually were similar (P>0.05) when exposed to same pore waters. Based on all considerations, this early‐life stage toxicity test shows promise being useful detecting pore water toxicity. This conclusion is based on availability of a test methodology which requires minimal space and effort, and the test species widespread geographical distribution. However, there are several remaining research needs, including the important issue of its sensitivity relative to that for other pore water test species as well as for species used in solid‐phase toxicity tests. © 2000 John Wiley & Sons, Inc. Environ Toxicol 15: 234–242, 2000     

Comparison of EMA and FDA guidelines for drug interactions: An overview

In 2013, the regulatory authorities of the European Union and the US issued, almost simultaneously, new editions of the industry guidelines for the requirements of drug testing during their development for drug–drug and drug–food interactions. That being said, there are significant differences in the requirements set by both guidelines, and the aim of this article is to point out those differences. In this review, the author carefully and comprehensively compared the publicly available guidelines via the official Food and Drug Administation’s (FDA) and European Medicine Agency’s (EMA) websites, highlighting the differences between the two sets. Unlike the guidelines provided by the FDA, the EMA guidelines lack set requirements for testing interactions with therapeutic proteins as well as with the usage of pharmacodynamics end-points. It also does not set standards for the use of the ‘no interaction’ declaration in the summary of product characteristics. On the other hand, the FDA currently lacks guidance for testing drug–food interactions, the use of the Relative Induction Score correlation method, and proving existence of reversible inhibition and mechanism-based inactivation. It is important to note that, while there are differences in the requirements for the FDA’s and the EMA’s drug interaction guidelines, they are not substantial and are mostly relating to the scope of requirements and precision of the standards set.