A Food Scare a Day: Why Aren't We Better at Managing Dietary Risk?

Does the existence of food scares mean that we are bad at risk management? Not necessarily. New information brings new risks to the forefront or puts known risks into a new perspective. But in some cases food scares do indicate poor risk management. There are two key problems that explain why we are not better at managing dietary risks. The first is an imbalance of effort among the three components of risk analysis: we have Hummer risk assessment, Yugo risk management, and tricycle risk communication. The second problem is inadequate risk management. The cases of risks from mad cow disease and dioxins illustrate how the quality of risk management is affected by what we do not know well enough, what we know too well, and what we have not tried to find out. Better risk management requires a two-tier approach: (1) generate broad and shallow information on risks, health outcomes, incentives, options, benefits, and costs (Toyota Prius Hybrid risk management to be used everyday) and (2) generate narrow and in-depth information on high priority risks (Hummer risk assessment to be used sparingly).     

Assessment of Health Protectiveness of the Risk-Based Soil Remediation Standards of the Midwestern States

In the last decade, risk-based remediation following a framework similar to risk-based correction action (RBCA) has gained acceptance across the country and generic/Tier 1 Risk-Based Action Limits (RBALs) for hundreds of chemicals have been tabulated. However, there have been only a few studies that focused on understanding the causes of discrepancy among cleanup standards and policies of the hazardous waste programs among the states. This study aims to fill this critical need by examining the basis of generic (i.e., Tier 1) residential RBALs developed by the states, which are within the regulatory domain of U.S. Environmental Protection Agency's Region 5. Specifically, we seek to investigate the approaches/methodologies and the policy/technical rationale used in establishing RBALs, along with degree of inconsistency, and the causes and implications of inconsistencies. In addition, we developed RBALs for a case study site using both deterministic and probabilistic risk assessment approaches and compared these against RBALs developed by the states to infer about public health-protectiveness of the state-specific RBALs. We found three- and four-order-of magnitude difference among state RBALs for PAHs and VOCs, respectively. The degree of clean up deemed appropriate under Tier 1 evaluation by the midwestern states significantly differ from one another, which has both public health and economic implications.     

美国州立公园体系的发展、特征与评估

美国州立公园与国家公园相比,更强调满足州内居民就近户外休闲游憩需求的功能,这使得其在美国整体公共户外休闲空间体系中占据特殊的位置。在中国第一次全面地研究了美国州立公园体系的发展、特征及与国家公园体系的关系,特别是以部分州为例研究了美国州立公园的分类、质量评估、可达性与空间分布评估等关键问题。研究认为,州立公园的意义在于既缓解了美国国家公园面临的巨大旅游游憩压力,也满足了大众户外休闲游憩的需求。这值得中国在目前构建国家公园与自然保护地体系的同时予以借鉴。最后基于中国的实际需求与挑战,探讨了在省域/区域层次加强构建地方公园、保护地和游憩地体系建设的必要性与途径。     

Leaf breakdown in streams differing in catchment land use

1. The impact of changes in land use on stream ecosystem function is poorly understood. We studied leaf breakdown, a fundamental process of stream ecosystems, in streams that represent a range of catchment land use in the Piedmont physiographic province of the south‐eastern United States. 2. We placed bags of chalk maple (Acer barbatum) leaves in similar‐sized streams in 12 catchments of differing dominant land use: four forested, three agricultural, two suburban and three urban catchments. We measured leaf mass, invertebrate abundance and fungal biomass in leaf bags over time. 3. Leaves decayed significantly faster in agricultural (0.0465 day^?1) and urban (0.0474 day^?1) streams than in suburban (0.0173 day^?1) and forested (0.0100 day^?1) streams. Additionally, breakdown rates in the agricultural and urban streams were among the fastest reported for deciduous leaves in any stream. Nutrient concentrations in agricultural streams were significantly higher than in any other land‐use type. Fungal biomass associated with leaves was significantly lower in urban streams; while shredder abundance in leaf bags was significantly higher in forested and agricultural streams than in suburban and urban streams. Storm runoff was significantly higher in urban and suburban catchments that had higher impervious surface cover than forested or agricultural catchments. 4. We propose that processes accelerating leaf breakdown in agricultural and urban streams were not the same: faster breakdown in agricultural streams was due to increased biological activity as a result of nutrient enrichment, whereas faster breakdown in urban streams was a result of physical fragmentation resulting from higher storm runoff.     

From Assessment to Policy: Lessons Learned from the U.S. National Assessment

The process of translating scientific information into timely and useful insights that inform policy and resource management decisions, despite the existence of uncertainties, is a difficult and challenging task. Policy-focused assessment is one approach to achieving this end. It is an ongoing process that engages both researchers and end-users to analyze, evaluate and interpret information from multiple disciplines to draw conclusions that are timely and useful for decision makers. This paper discusses key characteristics of a policy-focused assessment process, including (1) ongoing collaboration between the research, assessment, and stakeholder communities; (2) a focus on stakeholder information needs; (3) multidisciplinary approaches; (4) use of scenarios to deal with uncertainties; and (5) evaluation of risk management options. We illustrate the particular challenge to assessors of providing the specific types of insights stakeholders need to effectively influence policy decisions. And we discuss the role that assessment can play in formulating an agenda for future research. Examples from the U.S. National Assessment of “The Potential Consequences of Climate Variability and Change for the United States” are used to illustrate a policy-focused assessment process. For many of the participants, the first U.S. National Assessment was an extraordinary learning experience about how to develop better ways of conducting assessments.     

Distribution of Daily Breathing Rates For Use in California's Air Toxics Hot Spots Program Risk Assessments

Data were combined from a study measuring breathing rates at various activities and two activity pattern studies to generate breathing rate distributions for children and adults. The children and adult breathing rate distributions were combined using a Monte Carlo technique to generate a breathing rate distribution for a lifetime spanning ages 0 to 70. The children's breathing rate distribution has a mean, standard deviation, median and 95^th percentile of 452, 67.7, 441, and 581 L/kg-day, respectively. The adult breathing rate distribution has a mean, standard deviation, median and 95^th percentile of 232, 64.6, 209, and 381 L/kg-day, respectively. The simulated 70-year distribution has a mean, standard deviation, median and 95^th percentile of 271, 57.9, 253, and 393 L/kg-day, respectively. The adult breathing rate distribution is based on 24-hour recall activity data that would not necessarily capture average activity patterns and therefore breathing rates. We utilized the human energy expenditure literature to validate the breathing rate distribution. We conclude that the breathing rate distribution is reasonable for chronic long-term risk assessment in California's Air Toxics Hot Spots program.     

Estimation of Multimedia Inorganic Arsenic Intake in the U.S. Population

Arsenic is widely distributed in the environment by natural and human means. The potential for adverse health effects from inorganic arsenic depends on the level and route of exposure. To estimate potential health risks of inorganic arsenic, the apportionment of exposure among sources of inorganic arsenic is critical. In this study, daily inorganic arsenic intake of U.S. adults from food, water, and soil ingestion and from airborne particle inhalation was estimated. To account for variations in exposure across the U.S., a Monte Carlo approach was taken using simulations for 100,000 individuals representing the age, gender, and county of residence of the U.S. population based on census data. Our analysis found that food is the greatest source of inorganic arsenic intake and that drinking water is the next highest contributor. Inhalation of airborne arsenic-containing particles and ingestion of arsenic-containing soils were negligible contributors. The exposure is best represented by the ranges of inorganic arsenic intake (at the 10^th and 90^th percentiles), which were 1.8 to 11.4 µg/day for males and 1.3 to 9.4 µg/day for females. Regional differences in inorganic arsenic exposure were due mostly to consumption of drinking water containing differing inorganic arsenic content rather than to food preferences.     

Heider's "Anthropological Models of Incest Laws in the United States": A Comment

In his analysis of U.S. legal prohibitions of marriage with relatives, Heider rejects the Old Testament model as an explanation of the configuration of current state laws. Although Heider's statement is generally accurate, the statutes seem to express two basic models, an attenuated Biblical and a Western American pattern. These patterns are the inverse of each other with regard to prohibition of first-cousin marriage and marriage between affines. Historical review of statutes reveals a trend from Biblical to Western American patterns. The historical perspective suggests that confounding the two models may have weakened Heider's analysis.     

Improving the Applicability of Quantitative Ecological Risk Assessment Tools—Understanding Demand-Side Changes

Quantitative ecological risk assessment (ERA) methods are the tools of choice for many natural resource management agencies and practitioners. However, a number of researchers and practitioners have recently highlighted that the application of quantitative ERA tools has perhaps been somewhat limited and this has stimulated discussion on the limitations of these methods, considered to be supply-side limitations in this analysis. By contrast, it is argued here that the demand for risk assessment tools has also changed substantively and this also acts to limit the use of ERA approaches. In particular, demand has changed through an increasing expectation that quantitative ERA tools will be able to capture ecosystem-scale, and sometimes global-scale interactions to support ecosystem-based management approaches. Similarly, the burgeoning use of market-based policy instruments often underpinned by the allocation of private property rights to an increasing number of ecosystem goods and services has fundamentally changed many natural resource management issues into allocation conflicts between alternate rights-holders. These demand-side changes represent both an opportunity and a challenge for developers of quantitative ERA tools.     

Developing sustainable food supply chains

This paper reviews the opportunities available for food businesses to encourage consumers to eat healthier and more nutritious diets, to invest in more sustainable manufacturing and distribution systems and to develop procurement systems based on more sustainable forms of agriculture. The important factors in developing more sustainable supply chains are identified as the type of supply chain involved and the individual business attitude to extending responsibility for product quality into social and environmental performance within their own supply chains. Interpersonal trust and working to standards are both important to build more sustainable local and many conserved food supply chains, but inadequate to transform mainstream agriculture and raw material supplies to the manufactured and commodity food markets. Cooperation among food manufacturers, retailers, NGOs, governmental and farmers' organizations is vital in order to raise standards for some supply chains and to enable farmers to adopt more sustainable agricultural practices.     

Risk Assessment and Safety Evaluation Using Probabilistic Fault Tree Analysis

Risk assessment is an essential prelude to the development of accident prevention strategies in any chemical or petrochemical industry. Many techniques and methodologies such as HAZOP, failure mode effect analysis, fault tree analysis, preliminary hazard analysis, quantitative risk assessment and probabilistic safety analysis are available to conduct qualitative, quantitative, and probabilistic risk assessment. However, these methodologies are limited by: extensive data requirements, the length of study, results are not directly interpretable for decision making, simulation is often difficult, and they are applicable only at the operation or late design stage. Khan et al. (2001a) recently proposed a detailed methodology for risk assessment and safety evaluation. This methodology is simple, yet it is effective in safety and design-related decision making, and it has been applied successfully to many case studies. It is named SCAP, where S stands for safety, C and A stand for credible accident respectively, and P stands for probabilistic fault tree analysis. This paper recapitulates the SCAP methodology and demonstrates its application to a petrochemical plant.