Framework for the Integration of Health and Ecological Risk Assessment

The World Health Organization's International Programme on Chemical Safety (IPCS), the Organization for Economic Cooperation and Development (OECD), and the U.S. Environmental Protection Agency have developed a collaborative partnership to foster integration of assessment approaches for human health and ecological risks. This paper presents the framework developed by that group. Integration provides coherent expressions of assessment results, incorporates the interdependence of humans and the environment, uses sentinel organisms, and improves the efficiency and quality of assessments relative to independent human health and ecological risk assessments. The paper describes how integration can occur within each component of risk assessment, and communicates the benefits of integration at each point. The goal of this effort is to promote the use of this internationally accepted guidance as a basis for harmonization of risk assessment.     

Framework for Human Health Risk Assessment

The views expressed in this paper are those of the authors and do not necessarily reflect the views or policies of the USEPA. The U.S. Government has the right to retain a nonexclusive royalty-free license in and to any copyright covering this article. The U.S. Environmental Protection Agency has recognized the need to develop a framework for human health risk assessment that puts a perspective on the approaches in practice throughout the Agency. In response, the USEPA's Risk Assessment Forum has begun the process of developing a framework for human health risk assessment. This paper provides some additional background to the previous review of the framework efforts and notes the Agency's extramural efforts to begin the process of integrating and harmonizing risk assessment approaches for all human health endpoints.     

Multi-sensor assessment of dynamic balance during gait in patients with subacute stroke

The capacity to maintain upright balance by minimising upper body oscillations during walking, also referred to as gait stability, has been associated with a decreased risk of fall. Although it is well known that fall is a common complication after stroke, no study considered the role of both trunk and head when assessing gait stability in this population. The primary aim of this study was to propose a multi-sensor protocol to quantify gait stability in patients with subacute stroke using gait quality indices derived from pelvis, sternum, and head accelerations. Second, the association of these indices with the level of walking ability, with traditional clinical scale scores, and with fall events occurring within the six months after patients’ dismissal was investigated. The accelerations corresponding to the three abovementioned body levels were measured using inertial sensors during a 10-Meter Walk Test performed by 45 inpatients and 25 control healthy subjects. A set of indices related to gait stability were estimated and clinical performance scales were administered to each patient. The amplitude of the accelerations, the way it is attenuated/amplified from lower to upper body levels, and the gait symmetry provide valuable information about subject-specific motor strategies, discriminate between different levels of walking ability, and correlate with clinical scales. In conclusion, the proposed multi-sensor protocol could represent a useful tool to quantify gait stability, support clinicians in the identification of patients potentially exposed to a high risk of falling, and assess the effectiveness of rehabilitation protocols in the clinical routine.     

Multi-day Longitudinal Assessment of Physical Activity and Sleep Behavior Among Healthy Young and Older Adults Using Wearable Sensors

ObjectivesThe number of elderly people is growing rapidly and aging is found to affect activities of daily living. Older adults are found to perform less physical activity when compared to younger ones. In the perspective of movement behavior, it is not well understood how are elderly different from younger ones. It is not known whether they produce only low frequency movement accelerations or the overall number of movements produced are reduced in elderly. It is also not known how elderly and younger ones perform movement transitions throughout the duration of a day and during night-time sleep.Material and methodsIn this study, 10 healthy young and 10 healthy old participants wore inertial measurement unit at their lower back for 3-days. The 24 hours of day were divided into four 6 hour time zones and transitions made by young and elderly were investigated. All participants performed their regular daily activities unhindered and longitudinal multi-day signals for acceleration and angular velocity were analyzed. Time-frequency analysis was performed using wavelet transform and frequency content of each movement performed was computed.ResultsWe found that both young and older adults performed significantly more low amplitude movements than medium and high amplitude movements. Healthy young adults produced significantly more movements at 1.1 Hz than older adults. Healthy young adults were also found to have produced significantly smaller number of transitions in the mid-phases of sleep. They were also found to produce significantly larger accelerations during night-time sleep transitions than their older counterparts.ConclusionThe advantages of collecting longitudinal data about human movement and sleep transition data can lead us to important clinical diagnosis. The information from longitudinal assessment can help develop lifestyle interventions for disease prevention, monitoring of chronic diseases to prevent or slow disease progression among elderly people.     

A Wearable System for In-Home and Long-Term Assessment of Fetal Movement

Objectives: This paper presents a novel wearable system for in-home and long-term fetal movement monitoring on a reliable and easily accessible basis.Material and methods: The system mainly consists of four accelerometers for fetal movement signal acquisition, a microcontroller for signal processing and an Android-based device interacting with the microcontroller via Bluetooth Low Energy (BLE), providing the mother with information related to the fetal movement in an intelligible way.Results: The proposed system can deliver reliable results with a specificity of 0.99 and a sensitivity of 0.77 for fetal movement time series signal classification.Conclusion: The proposed wearable system will provide a good alternative to optimize the use of medical professionals and hospital resources, and has potential applications in the field of e-Health home care. Besides, the fetal movement acceleration signals acquired with volunteers (pregnant women) help establish an initial database for future medical analysis of sensor-recorded fetal behaviors.     

Overcoming the limitations of the Harmonic Ratio for the reliable assessment of gait symmetry

The Harmonic Ratio (HR) is an index based on the spectral analysis of lower trunk accelerations that is commonly used to assess the quality of gait. However, it presents several issues concerning reliability and interpretability. As a consequence, the literature provides very different values albeit corresponding to the same populations. In the present work, an improved harmonic ratio (iHR) was defined, relating the power of the intrinsic harmonics (i.e. associated with the symmetric component of gait) to the total power of the signal for each stride, leading to a normalised index ranging from 0 to 100%. The effect of the considered number of harmonics and strides on the estimate of both HR and iHR was assessed. The gait of three groups of volunteers was investigated: young healthy adults, elderly women and male trans-femoral amputees. Both HR and iHR were able to discriminate gait deviations from the gait of young healthy adults. Moreover, iHR proved to be more robust with respect to the number of considered harmonics and strides, and to exhibit a lower inter-stride variability. Additionally, using a normalised index as iHR led to a more straightforward interpretation and improved comparability. The importance of standardised conditions for the index evaluation was unveiled, and, in order to enhance the future comparability of the index, the following guidelines were presented: considering at least 20 harmonics and 20 strides; expressing the acceleration components in a repeatable, anatomical, local system of reference; and evaluating the iHR index, rather than the traditional HR.     

A Risk Assessment Framework for Waterborne Pathogens and Requirements for Producing a Complete Protocol

The U.S. Environmental Protection Agency (USEPA), Office of Water, is developing a risk assessment protocol for determining microbiological pathogen risks in water (drinking, recreational, waste waters, etc.). This effort has been conducted in collaboration with the International Life Sciences Institute. A microbiological risk assessment framework was prepared and has been peer reviewed in the open literature and vetted at the USEPA and other federal government risk assessment venues. Some goals in development of the Framework were to make it comprehensive, easy to understand and to use, since it is recognized that improvements to the framework structure and instructional material would facilitate its use. The USEPA's Office of Water wishes to develop improved tools, methods, and approaches for conducting the analysis phase for risk assessments and would like to evaluate its efficacy for a broad range of waterborne pathogens in water/wastewater media. Improved understanding of microbiological survival, infectivity, and virulence factors is needed, especially at the genomic and proteomic levels to accurately assess the occurrence and fate of pathogens in water and to predict what intrinsic factors allow pathogens to be invasive and virulent. Development of improved dose-response models (including animal models) for pathogen exposures focusing on the dynamic circumstances of immunity, secondary spread, and sensitive subpopulations, would be useful additions to the Framework. In the future, USEPA may consider establishing comprehensive pathogen risk assessment guidelines that all its program offices can use.     

Ecological Risk Assessment Approaches Within the Regulatory Framework

Ecological risk assessment has a short history but a framework similar to human health risk assessment. The Toxic Substances Control Act (TSCA) and the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) played a significant role in the development of the ecological risk process. Data developed and risk procedures used within TSCA and FIFRA have become generally standardized. Fundamental components of the risk process require data on the effects of chemicals in the form of concentration (or dose) — response profiles for species and an exposure profile to quantify the magnitude, spatial and temporal patterns of exposure relevant to significant biological endpoints being studied. Risk characterization generally involves comparing exposure and effects using point estimates (e.g., quotient method) but risk estimation is moving toward a probabilistic approach by comparing distributions of values with more consideration of the sources of uncertainty. Ecological testing guidelines in TSCA and FIFRA are discussed along with the risk characterization process used in each statute.     

Trends in the Development of Ecological Risk Assessment and Management Frameworks

Ecological risk assessment and management have grown from a long history of assessment and management activities aimed at improving the everyday lives of humans. The background against which ecological risk assessment and management has developed is discussed and recent trends in the development of risk assessment and management frameworks documented. Seven frameworks from five different countries are examined. All maintain an important role for science, suggest adaptive approaches to decision-making and have well-defined analytical steps. Differences in approaches toward the separation of policy and science, the preference for management over assessment, the inclusion of stakeholders, the iterative nature of the analytical cycle, the use of decision criteria and economic information suggest considerable evolution in framework design over time. Despite the changes, no consensus on the design of a framework is apparent and work remains to be done on refining an integrative framework that effectively incorporates both policy and science considerations for environmental management purposes.     

Validity and reliability of a shoe-embedded sensor module for measuring foot progression angle during over-ground walking

Wearable systems are becoming increasingly popular for gait assessment outside of laboratory settings. A single shoe-embedded sensor module can measure the foot progression angle (FPA) during walking. The FPA has important clinical utility, particularly in populations with knee osteoarthritis, as it is a target for biomechanical treatments. However, the validity and the day-to-day reliability of FPA measurement using wearable systems during over-ground walking has yet to be established. Two gait analysis sessions on 20 healthy adults were conducted. During both sessions, participants performed natural over-ground walking in a motion capture laboratory and on a 100 m linear section of outdoor athletics track. FPA was measured in the laboratory via marker trajectory data, while the sensor module measured FPA during the outdoor track walking. Validity was examined by comparing the laboratory- and sensor-measured average FPA. Day-to-day reliability was examined by comparing the sensor-measured FPA between the first and second gait analysis sessions. Average absolute error between motion capture and sensor measured FPA were 1.7° and 2.1° at session 1 and 2, respectively. A Bland and Altman plot indicated no systematic bias, with 95% limit of agreement widths of 4.2° – 5.1°. Intraclass correlation coefficient (ICC_2k) analysis resulted in good to excellent validity (ICC = 0.89 – 0.91) and reliability (ICC = 0.95). Overall, the shoe-embedded sensor module is a valid and reliable method of measuring FPA during over-ground walking without the need for laboratory equipment.     

The Ecological Component of Ecological Risk Assessment: Lessons from a Field Experiment

To improve ecological relevance, regulatory agencies are promoting assessments of effects at higher levels of organization, an objective that requires an understanding of current ecological theories. One such theory, hierarchy theory, contends that the effects of a disturbance acting at one level of organization (e.g., population) are not, as a rule, transmitted to higher levels of organization (e.g., community). Conversely, effects at higher levels of organization only occur if lower level variables have been affected. Further, responses to disturbance depend on disturbance history. In this study, I determined the effects of a disturbance treatment at the population, guild, and community levels of organization for vegetation in five wetlands with a disturbance history ranging from highly to rarely disturbed. The 2-year field experiment revealed that the effects of the disturbance treatment were most strongly felt at the population level of organization in wetlands without a history of disturbance. These observed impacts took place against a backdrop of constant change. Thus, the eventual disappearance of treatment effects was not due to a return to the pre-treatment state, but rather a return to a trajectory similar to that exhibited by the control plots. The implications of these results for ecological risk assessment are: (1) the observed effects of a stressor in a system cannot be extrapolated to other systems unless they have similar disturbance histories, (2) detecting effects before they become serious requires monitoring at lower levels of organization, (3) recovery to a naturally innate state is not a viable concept, and (4) the traditional approach of using one post-treatment measurement to determine if reference and impact sites differ is of very questionable value.     

Development of a Relative Ranking Risk Index for Risk Assessment in the Transportation of Liquefied Petroleum Gas in Mexico City's Metropolitan Area

The development of a relative ranking methodology created specifically for the assessment of the risk due transportation of Liquefied Petroleum Gas (LPG) in Mexico City is reported. Mexico City has a number of conditions that present specific challenges: Large population, varied geography, large consumption of LPG, and all sorts of vehicles, including those for LPG. Given Mexico's status as “emerging economy,” it is reasonable to assume that the main causes that promote accidents during transportation of LPG are quite different from those in developed countries. This issue was corroborated through information from official sources and from news media. Due to the lack of official data, a systematic collection of information on the media was performed. A relative ranking methodology was developed based on a systematic study to elucidate the main causes of accidents in Mexico and on the results derived from the integrated database from official data and the media. The weighting that made up the Risk Index for Transportation of LPG is based on the same database. A classification guide was created in order to harmonize criteria in the assessment of the parameters of the proposed risk index.     

基于FMEA和POSSUM评分的手术风险评估研究

??????? 目的 研究建立手术风险评估的架构,以正确决策手术时机。方法 采用用于计数死亡率和并发症发生率的生理学和手术严重性（POSSUM）评分原理进行分层计分,同时引用失效模式与效应分析方法对手术可能发生故障模式的严重度及发生可能性及风险因素的影响度3个维度进行评估。结果 建立了手术前风险预警机制及手术评估架构,利用评估架构对某综合医院2010年200例80岁高龄的手术病人进行了术前评估,结果手术后并发症的发生率较2009年同年龄的手术病人的并发症下降了10.45%。结论 在手术前对手术相关因素进行评估,可以为手术时机的选择提供参考。     

Muscle activity patterns of the tensor fascia latae and adductor longus for ramp and stair walking

Walking on both outdoor and indoor surfaces requires the ability to negotiate connections between vertical distances, simply known as hills and stairs. Therefore, the purpose of the present study was to evaluate the muscle activity patterns of the TFL and ADL during both hill and stair walking. We hypothesized that TFL and ADL activity during initial swing, initial stance, and late stance of up-ramp and up-stair walking would be greater than level walking. In contrast, we hypothesized that both TFL and ADL activity during initial swing of down-ramp and down-stair walking would be less. We utilized a 15° ramp, a 35° stair set, and for comparison of this steep angle, we also collected data on a 33° ramp. During up-ramp and up-stair walking, TFL and ADL activity during both initial swing and late stance of the up conditions were greater than level walking. For the down conditions, ADL activity during the swing phase of the steep down-ramp was less. Practically, our muscle activity results demonstrate that the hip abductors and hip adductors may provide additional pelvic stability and supplementary thigh acceleration during ramp and stair walking.     

Practical Issues in the Use of Probabilistic Risk Assessment

Probabilistic risk assessment (PRA) represents an important step in the evolution of risk assessment methodology to assist decision-making at hazardous waste sites. Despite considerable progress in the development of PRA techniques, regulatory acceptance of PRA has been limited, in part because a number of practical issues in its use must yet be resolved. A recent workshop on PRA identified several areas to be addressed, including the need for: (1) better demonstration of the value of PRA in risk management; (2) PRA training and education opportunities; (3) the development of technical criteria for acceptability of a PRA; (4) policy decisions on acceptable risk distributions; (5) ways to deal with risk communication issues; and (6) a variety of technical issues, including ways to include estimates of variability and uncertainty associated with toxicity values. Solutions to many of these issues will require better dialog between risk assessors and risk managers than has existed in the past.     

Focus: Sex and Gender Health: Perceived Fall Risk and Functional Decline: Gender Differences in Patient's Willingness to Discuss Fall Risk,Fall History,or to Have a Home Safety Evaluation

The CDC reports that among older adults, falls are the leading cause of injury-related death and rates of fall-related fractures among older women are twice those of men. We set out to 1) determine patient perceptions (analyzed by gender) about their perceived fall risk compared to their actual risk for functional decline and death and 2) to report their comfort level in discussing their fall history or a home safety plan with their provider. Elders who presented to the Emergency Department (ED†) were surveyed. The survey included demographics, the Falls Efficacy Scale (FES) and the Vulnerable Elders Survey (VES); both validated surveys measuring fall concern and functional decline. Females had higher FES scores (mean 12.3, SD 5.9) than males (mean 9.7, SD 5.9 p = .007) in the 146 surveys analyzed. Females were more likely to report an increased fear of falling, and almost three times more likely to have a VES score of 3 or greater than males (OR = 2.86, 95% CI: 1.17-7.00, p = .02). A strong correlation was observed between FES and VES scores (r = 0.80, p < .001). No difference in correlation was observed between males and females, p = .26. Participants (77 percent) reported they would be comfortable discussing their fall risk with a provider; there was no difference between genders (p = .57). In this study, irrespective of gender, there appears to be a high association between subjects’ perceived fall risk and risk for functional decline and death. The majority of patients are likely willing to discuss their fall risk with their provider. These findings may suggest a meaningful opportunity for fall risk mitigation in this setting.     

Safety Risk Assessment and Improvement in a Food Production Process

The food industry is under pressure to improve food safety, implement efficient risk management, and control quality “from farm to fork.” During processing of raw materials into packaged consumable products, food may be influenced by biological and chemical pollution and other various environmental factors. Risk assessment of a food production process was studied in this work. The novelty of this work lies in analyzing the development laws of food safety risk in serial and parallel modes, and developing a heuristic algorithm of polynomial time to minimize safety risks in food production with a constant budget. This algorithm was validated by a numerical example of peanut milk production. The primary procedures in peanut milk production were found and the advice on investment allocation was given to improve production.