Trends in ambient concentrations of agrochemicals in humans and the environment of the United States

Uses of pesticides and related agrochemicals have been regulated in the United States since 1948. The United States government has supported human and environmental monitoring for pesticides and selected toxic chemicals for the past 15 yr. The initial ambient monitoring systems were designed to determine average concentrations of pesticides and related chemicals in human and environmental media on a nationwide basis and determine changes in these concentrations over time. The results of these surveys showed that almost all of the general human population and various environmental components contained low concentrations of chlorinated pesticides. As the Environmental Protection Agency (EPA) restricted many uses of the chlorinated pesticides, the organophosphorous and carbamate pesticides which replaced them were not as easily monitored by ambient surveys. Special monitoring studies had to be done more frequently to produce data on these compounds which were not as persistent or accumulative in the environment. Currently, a re-evalution has begun to determine pesticide monitoring data needs for the next 5 to 10 yr, modify existing ambient surveys, and plan needed short-term studies to efficiently meet regulatory data needs. Ambient monitoring for trends in chemical levels in humans and the environment will continue in the United States at a reduced level, and many exposure data needs will be met with use-specific monitoring studies.Presented at the International Conference on Environmental Hazards of Agrochemicals in Developing Countries, 8–12 November, 1983 in Alexandria, Egypt.     

Empirical evaluation of spatial and non-spatial European-scale multimedia fate models: results and implications for chemical risk assessment

Multimedia environmental fate models are commonly-applied tools for assessing the fate and distribution of contaminants in the environment. Owing to the large number of chemicals in use and the paucity of monitoring data, such models are often adopted as part of decision-support systems for chemical risk assessment. The purpose of this study was to evaluate the performance of three multimedia environmental fate models (spatially- and non-spatially-explicit) at a European scale. The assessment was conducted for four polycyclic aromatic hydrocarbons (PAHs) and hexachlorobenzene (HCB) and compared predicted and median observed concentrations using monitoring data collected for air, water, sediments and soils. Model performance in the air compartment was reasonable for all models included in the evaluation exercise as predicted concentrations were typically within a factor of 3 of the median observed concentrations. Furthermore, there was good correspondence between predictions and observations in regions that had elevated median observed concentrations for both spatially-explicit models. On the other hand, all three models consistently underestimated median observed concentrations in sediment and soil by 1-3 orders of magnitude. Although regions with elevated median observed concentrations in these environmental media were broadly identified by the spatially-explicit models, the magnitude of the discrepancy between predicted and median observed concentrations is of concern in the context of chemical risk assessment. These results were discussed in terms of factors influencing model performance such as the steady-state assumption, inaccuracies in emission estimates and the representativeness of monitoring data.     

Estimating overall persistence and long-range transport potential of persistent organic pollutants: a comparison of seven multimedia mass balance models and atmospheric transport models

Two different approaches to modeling the environmental fate of organic chemicals have been developed in recent years. The first approach is applied in multimedia box models, calculating average concentrations in homogeneous boxes which represent the different environmental media, based on intermedia partitioning, transport, and degradation processes. In the second approach, used in atmospheric transport models, the spatially and temporally variable atmospheric dynamics form the basis for calculating the environmental distribution of chemicals, from which also exchange processes to other environmental media are modeled. The main goal of the present study was to investigate if the multimedia mass balance models CliMoChem, SimpleBox, EVn-BETR, G-CIEMS, OECD Tool and the atmospheric transport models MSCE-POP and ADEPT predict the same rankings of the overall persistence (P(ov)) and long-range transport potential (LRTP) of POPs, and to explain differences and similarities between the rankings by the mass distributions and inter-compartment mass flows. The study was performed for a group of 14 reference chemicals. For P(ov), the models yield consistent results, owing to the large influence of phase partitioning parameters and degradation rate constants, which are used similarly by all models. Concerning LRTP, there are larger differences between the models than for P(ov), due to different LRTP calculation methods and spatial model resolutions. Between atmospheric transport models and multimedia fate models, no large differences in mass distributions and inter-compartment flows can be recognized. Deviations in mass flows are mainly caused by the geometrical design of the models.     

The environmental specimen banking project of the Federal Republic of Germany

Thousands of chemicals are on the market, but only in a few exceptional cases is it known where these chemicals remain in the environment and what effects they are able toexert in correlation to their environmental concentration. In addition to monitoring the actual concentrations of chemicals in the environment, it is necessary to establish an environmental specimen banking program which will, in the future, make possible the retrospective monitoring of chemicals. The feasibility of such a program is being studied in a joint U.S.-German pilot project. The German project is described here, including its organizational structure, technical and scientific considerations, and methods of specimen selection.     

Recommendations for Monitoring of Polybrominated Diphenyl Ethers in the Canadian Environment

Polybrominated diphenyl ethers (PBDEs) have been reported in air, surface waters, suspended sediments, soil, sediment, fish, marine mammals, and bird eggs throughout Canada, from the St. Lawrence Estuary to the Strait of Georgia and the northernmost reaches of the Canadian Arctic. Canadian scientists have detected the presence of PBDEs in breast milk in every Canadian province. In fact, recent data on temporal trends strongly suggests that the concentrations of PBDEs are on the rise in the Canadian environment. These findings are similar to those reported in other nordic countries, and have prompted several countries to implement environmental monitoring programs. Among the key challenges currently facing Canada and other countries concerns how best to measure these chemicals in different matrices. In this paper, several analytical methods cited in the scientific literature for determining PBDE concentrations in different abiotic and biological matrices are reviewed. The critical criteria required for accurate determination of PBDEs in complex environmental matrices are discussed, including instrument sensitivity, reliability, potential interference's and the need for specialized instrumentation for the determination of compounds up to 975 Daltons. While a single analytical method that meets these and other criteria has not yet been perfected by scientists, GC/HRMS-based methods amenable to isotope dilution techniques warrant further refinement, and likely represent the best tools for future environmental monitoring programs.     

Synthetic musks in environmental samples: indicator compounds with relevant properties for environmental monitoring

Synthetic musks (nitro and polycyclic musks) are a group of chemicals offering a wide range of important properties for environmental monitoring programs. They are produced as odorous chemicals and added to a wide variety of perfumes, toiletry products and other household products. As such, they are directly applied in cosmetic products or in washed textiles to the human body in considerable concentrations and accumulate owing to dermal resorption. In addition, synthetic musks also enter the environment via waste water treatment. Several polycyclic musks are chiral. By using chiral gas chromatographic methods, it is possible to determine the enantiomeric ratio and assess their bioavailability. Although an comprehensive quality assurance program must be followed during the analysis of synthetic musks in environmental samples, the determination of these compounds is not very demanding and can be carried out by a standard analytical laboratory specialising in trace analysis of organic pollutants. Owing to the pheromone-like behavior of some synthetic musks, the induction of receptors in olfactory systems should be investigated. For HHCB (1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[g]-2-benzopyran, e.g., Galaxolide), three-dimensional structural similarities with androstenone (5 alpha-androst-16-en-3-one), a mammalian steroid pheromone, were found, which support the hypothesis of HHCB as an artificial pheromone. Owing to their environmental abundance, their relation to human activities and their potential for pheromone-like environmental behavior, synthetic musks are especially valuable as future indicator chemicals for environmental monitoring.     

Human Health Effects of Environmental Pollutants: New Insights

While a variety of effects of toxic chemicals are known in animals exposed both in the laboratory and in situ, it has proven more difficult to obtain definitive information relating harm to humans resulting from environmental contamination. Until quite recently it has been generally assumed that cancer was the human disease of greatest importance. In fact, the majority of regulations of exposure to toxic chemicals by most governments are designed on the basis of presumed cancer risk. The evidence that hazardous chemicals can cause cancer is strong, and concern of cancer risks is appropriate. However, recent evidence has triggered a reevaluation of the assumption that cancer is the sole disease of concern. New evidence has emerged suggesting that exposure to hazardous chemicals may lead to a variety of non-cancer endpoints, and that these effects may occur at low concentrations. Of particular concern is evidence for irreversible effects on the embryo and very young children which influence intelligence, attention span, sexual development and immune function. Some of these actions appear to be direct effects on the brain and other organ systems while others are mediated via disruption of endocrine systems. While these effects are subtle and difficult to quantify, the aggregated evidence is sufficiently compelling as to necessitate reevaluation of those health outcomes upon which regulations are based.     

典型新兴环境污染物的研究进展

概述了内分泌干扰物(EDCs)、药物及个人护理品(PPCPs)等典型新兴环境污染物的主要类型、环境浓度、分析方法、来源与归趋以及国内外研究进展。内分泌干扰物、药物及个人护理品在世界各地的污水处理厂出水中检出,表明了污水处理技术的不完善性,亟需研究并应用更全面的污水处理技术,以从源头上阻断新兴环境污染物对环境的污染。     

Bioavailability assessment of phosphorus and metals in soils and sediments: a review of diffusive gradients in thin films (DGT)

This paper provides an overview of the principle and latest development of the diffusive gradients in thin films (DGT) technology and its applications in environmental studies with a focus on bioavailability assessment of phosphorus and metals in sediments and soils. Compared with conventional methods, DGT, as a passive sampling method, has significant advantages: in situ measurement, time averaged concentrations and high spatial resolution. The in situ measurement avoids artificial influences including contamination of samples and sample treatment which may change the forms of chemicals. The time averaged concentration reflects representative measurement over a period of time. The high-resolution information captures the biogeochemical heterogeneity of elements of interest distributed in microenvironments, such as in the rhizosphere and the vicinity of the sediment-water interface. Moreover, DGT is a dynamic technique which simultaneously considers the diffusion of solutes and their kinetic resupply from the solid phases. All the advantages of DGT significantly promote the collection of “true” information of the bioavailable or labile forms of chemicals in the environment. DGT provides potential for applications in agriculture, environmental monitoring and the mining industry. However, the applications are still at the early testing stage. Further studies are needed to properly interpret the DGT-measured results under complex environmental conditions, and standard procedures and guideline values based on DGT are required to pave the way for its routine applications in environmental monitoring.     

新型全氟化合物——全氟烷基磷酸对环境影响的研究综述

全氟烷基磷酸是一种新型全氟化表面活性剂,被广泛应用于匀染剂、湿润剂和农药中的消泡添加剂等。在美国,基于对其潜在毒性的考虑,美国环境保护总署已禁止全氟烷基磷酸在粮食作物农药中使用。从全氟烷基磷酸的注册使用情况、结构与环境行为、环境介质中的浓度水平和生物暴露毒性等方面分别展开论述,旨在为中国开展该类物质的环境研究提供可借鉴依据。     

Changes in thyroid peroxidase activity in response to various chemicals

Thyroperoxidase (TPO) is a large heme-containing glycoprotein that catalyzes the transfer of iodine to thyroglobulin during thyroid hormone (TH) synthesis. Previously, we established an in vitro assay for TPO activity based on human recombinant TPO (hrTPO) stably transfected into human follicular thyroid carcinoma (FTC-238) cells. It is important to determine whether environmental chemicals can disrupt TPO activity because it is an important factor in the TH axis. In this study, we used our assay to examine the changes in TPO activity in response to various chemicals, including benzophenones (BPs), polycyclic aromatic hydrocarbons (PAHs), and persistent organic pollutants (POPs). Overall, BPs, PAHs, and POPs slightly altered TPO activity at low doses, as compared with the positive controls methimazole (MMI), genistein, and 2,2',4,4'-tetrahydroxy BP. Benzophenone, benzhydrol, 3-methylchloranthracene, pyrene, benzo(k)fluoranthene, benzo(e)pyrene, perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and heptachlor decreased TPO activity, while 2,4-dihydroxy BP, 2,2'-dihydroxy-4-methoxy BP, and dibenzo(a,h)anthracene increased TPO activity. From these data, we can predict the disruption of TPO activity by various chemicals as a sensitive TH end point. TPO activity should be considered when enacting measures to regulate environmental exposure to thyroid-disrupting chemicals.     

Design of an integrated monitoring programme in Sweden

A National Swedish Environmental Monitoring Programme, the PMK, has been designed for regular and permanent recording of environmental conditions and long-term changes in background regions, and for keeping track of the flux of pollutants in and between various media. Many of the projects involved deal with integrated monitoring of terrestrial and limnic ecosystems. This work is carried out in or near some 20 small watersheds, usually selected in national parks or nature reserves. The environmental factors monitored in these areas include concentrations of chemical substances in precipitation, soil, groundwater, surface water, and organisms, as well as biological parameters—such as the population size and reproductive capacity of certain species—that may indicate effects of environmental disturbances. The data from this programme can be used as a reference to environmental data acquired near pollution sources, and as a basis for measures against e.g. acid rain, heavy-metal pollution, and use of pesticides. The biological parameters may also reveal effects of yet unknown pollutants or other disturbances.     

Risk assessment near uncontrolled hazardous waste sites: Role of monitoring data

The traditional approach of coupling estimates of human exposures to individual chemicals with laboratory studies of the toxicity of the chemicals as the basis for quantitative assessments of risk is not adequate when considering problems near hazardous waste sites. For example, there are (a) too many chemicals and mixtures involved, (b) containment uncertainties, and (c) future exposure problems associated with groundwater and soil contamination. Among the items to be considered in expanding the dimensions of risk assessment methodologies of the past are (a) identification of chemical groups or of dominant toxic chemicals of principal concern and the likely man-made as well as natural pathways for environmental migration, (b) the role of biological monitoring in addition to traditional monitoring approaches, and (c) the coupling of monitoring data with past, current, and future population activity patterns and with epidemiological and other health data.Monitoring data is a key in risk assessments since there is little likelihood that materials balances or modelling will provide authoritative information concerning exposure levels. The use of monitoring data from control areas and from nationwide baseline surveys in developing comparative risk assessments is particularly important. Finally, recent experience provides us with a number of practical guidelines for designing and carrying out monitoring programs that will provide authoritative and useful data. *** DIRECT SUPPORT *** AZ802019 00002     

Monitoring of cyclic organochlorines in the marine environment

Cyclic organochlorines are highly hydrophobic chemicals which usually possess a high persistence to microbial breakdown. These behavioural aspects determine the suitability of each environmental compartment for monitoring purposes, which is discussed.It is concluded, that monitoring of (cyclic) organochlorines should only be executed for compounds about which solid information is available on their environmental behaviour in abiotic and biotic environmental compartments. Under these conditions benthic invertebrates which use glycogen as their main energy-depot, appear to be the most suitable tool for environmental monitoring of lipophilic compounds. Concentrations should be expressed on the basis of (total) extractable lipids.The organisms to be compared should be sampled at a time when they have a similar physiological condition. This does not automatically mean synoptic sampling.Multi-component mixtures, such as PCB's, should be monitored on the basis of (selected) individual components in order to account for differences in behaviour of each component between different environmental compartments and animal species.Some representatives of the compounds discussed are strong inducers of mixed function oxygenase (MFO) enzyme systems. Therefore it should be investigated, if monitoring of MFO activity in addition to concentrations can be regarded as an early warning system of additive effects.     

Brominated flame retardants in the environment of Asia-Pacific: an overview of spatial and temporal trends

In this paper, we summarize spatial and temporal trends of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) in coastal and marine biota, and further assess human exposure to these brominated flame retardants (BFRs) in Asia-Pacific. The review is based mainly on the studies that were conducted in our laboratory and utilized samples archived in the environmental specimen bank (es-BANK) of Ehime University, Japan. The studies suggest that the target BFRs are ubiquitous in the environment of Asia-Pacific. Examination of spatial trends reveals that concentrations of these contaminants are relatively high in samples from Korea, South China and Japan. In general, the magnitude of environmental contamination by PBDEs in Asia-Pacific, as well as human exposure to these contaminants, seem to be comparable to or slightly higher than in Europe, but lower than in North America. Evaluation of temporal trends in concentrations of BFRs in marine mammals from the coastal waters of Japan and China showed drastic increase during the last 30 years. These changes in BFR levels in samples from Japan were in line with trends in production/use of the commercial formulations. Since the withdrawal of some PBDE products from the Japanese market in the 1990s, concentrations of HBCDs appear to exceed those of PBDEs, reflecting increasing usage of HBCDs over PBDEs. The increasing environmental contamination by BFRs in Chinese coastal waters indicates that contamination by BFRs has already become evident, even in developing countries. In view of the rising environmental levels and the high consumption volume of BFRs in Asia, further efforts should be made to monitor environmental contamination by these chemicals in order to identify sources and reduce emissions.     

江苏省“八五”环境质量声像报告书的研究

“江苏省”‘八五’环境质量声像报告书“是以江苏省”八五期间近５００万个监测数据为基础，运用地理信息系统和多媒体技术制作的集声，像图和文字为一体的环境质量计算机演示系统。该系统生动，直观地表征了江苏省“八五”环境质量状况及变化趋势。它的研制成功是环境质量表征技术的重要突破。     

Environmental assessment of water,chemicals and effluents in leather post-tanning process: A review

The leather industry has significant consumption of water and chemicals and generates liquid effluents with a high pollution load. This study aims to contribute to the advance of liquid effluents, water, and chemicals management in tanneries since the assessment of these environmental issues for each step of the post-tanning process remains unknown. Forty-three post-tanning formulations were obtained from scientific papers, catalogs from chemical manufacturers and tanneries, and their data were analyzed. Results showed an average chemical consumption of 360.2 kg per ton of shaved leather. Retanning and fatliquoring steps are the largest chemical consumers. The average water demand of this process is 8.6 cubic meters per ton of shaved leather, with washing responsible for the highest consumption. The raw wastewater is poorly biodegradable, with high conductivity and elevated concentration of salts. The results obtained in this study contribute to reduce the environmental impacts of leather post-tanning, guiding future studies aiming to optimize this process.     

Kinetic Analysis: Benzo(a) pyrene in Southeastern Ohio

Kinetic Analysis has been successful for metallic elements in relatively isolated areas. In this study it is applied to a complex organic compound in a geographical area with a large urban component. Ten media compartments are included, with man as the ultimate receptor. Field data were collected for only 6 of the media and were not used in the analysis but were compared to the calculated steady state concentrations. The greatest differences between calculated and observed values were 4.8-fold for soil and 5.4-fold for sediment. The field sampling regime for soils was biased towards areas of industrialization and probably explains the higher observed value. The lower observed value for sediment is likely due to unknown variables necessary for the estimation of the compartment size and/or the associated transfer rate constants. This study indicated that the Kinetic Analysis technique can be applied successfully to the pre-sampling estimation of the distribution of organic pollutants in environmental systems.     

Kriging for estimating spatial pattern of contaminants: Potential and problems

This paper discusses and illustrates the use of kriging techniques for estimating the spatial pattern of contaminants in environmental media, particularly soil. The assumptions underlying kriging are reviewed as are some advantages and disadvantages of the method. Lognormal kriging (kriging applied to logarithmic-transformed data) is illustrated using a set of radionuclide soil concentrations at a nuclear testing area on the Nevada Test Site. This example shows how lognormal kriging can be used to estimate average concentrations at points or for blocks of land, concentration contours over space, confidence bands about these contours, and radionuclide inventory in soil. The validity of kriging estimates depends on the accurate estimation and modeling of the spatial correlation structure of the phenomenon. Accuracy is especially important when lognormal kriging is used and estimates of means and their standard deviations are required in the original, untransformed scale. This paper illustrates the bias that can result when a changing correlation structure over space is ignored.Operated for the U.S. Department of Energy by Battelle Memorial InstituteWork supported by Nevada Applied Ecology Group, U.S. Department of Energy, Nevada Operations Office under Contract DE-AC06-76RLO 1830.