Quantifying health risks in wastewater irrigation

The guidelines developed by the World Health Organization for the safe use of wastewater in agriculture are based on a tolerable additional disease burden of 10-6 disability-adjusted life year loss per person per year, equivalent to rotavirus disease and infection risks of approximately 10-4 and 10-3 per person per year, respectively. The combination of standard quantitative microbial risk analysis techniques and 10,000-trial Monte Carlo risk simulations, using ranges of parameter values that reflect real life, are then used to determine the minimum required pathogen reductions for restricted and unrestricted irrigation which ensure that the risks are not exceeded. For unrestricted irrigation the required pathogen reduction is 6- 7 log10 units and for restricted irrigation 3- 4 log10 units. For both restricted and unrestricted irrigation wastewater treatment has to achieve a 3-4-log10 unit pathogen reduction, and in the case of unrestricted irrigation this has to be supplemented by a further 3-4-log10 unit pathogen reduction provided by post-treatment, but pre-ingestion, health protection control measures, such as pathogen die-off between the last irrigation and consumption (0.5- 2 log10 unit reduction per day, depending on ambient temperature) and produce washing in clean water (1 log10 unit reduction). Wastewaters used for both restricted and unrestricted irrigation also have to contain no more than 1 human intestinal nematode egg per liter; if children under the age of 15 are exposed then additional measures are required such as regular deworming at home or at school

Probabilities and health risks: a qualitative approach

Health risks, defined in terms of the probability that an individual will suffer a particular type of adverse health event within a given time period, can be understood as referencing either natural entities or complex patterns of belief which incorporate the observer's values and knowledge, the position adopted in the present paper. The subjectivity inherent in judgements about adversity and time frames can be easily recognised, but social scientists have tended to accept uncritically the objectivity of probability. Most commonly in health risk analysis, the term probability refers to rates established by induction, and so requires the definition of a numerator and denominator. Depending upon their specification, many probabilities may be reasonably postulated for the same event, and individuals may change their risks by deciding to seek or avoid information. These apparent absurdities can be understood if probability is conceptualised as the projection of expectation onto the external world. Probabilities based on induction from observed frequencies provide glimpses of the future at the price of acceptance of the simplifying heuristic that statistics derived from aggregate groups can be validly attributed to individuals within them. The paper illustrates four implications of this conceptualisation of probability with qualitative data from a variety of sources, particularly a study of genetic counselling for pregnant women in a U.K. hospital. Firstly, the official selection of a specific probability heuristic reflects organisational constraints and values as well as predictive optimisation. Secondly, professionals and service users must work to maintain the facticity of an established heuristic in the face of alternatives. Thirdly, individuals, both lay and professional, manage probabilistic information in ways which support their strategic objectives. Fourthly, predictively sub-optimum schema, for example the idea of AIDS as a gay plague, may be selected because they match prevailing social value systems

Competitive Markets with Endogenous Health Risks

We study a general equilibrium model where agents’ preferences, productivity and labor endowments depend on their health status, and occupational choices affect individual health distributions. Efficiency typically requires agents of the same type to obtain different expected utilities if assigned to di¤erent occupations. Under mild assumptions, workers with riskier jobs must get higher expected utilities if health a¤ects production capabilities. The same holds if health affects preferences and health enhancing consumption activities are sufficiently effective, so that income and health are substitutes. The converse obtains when health a¤ects preferences, but health enhancing consumption activities are not very effective, and hence income and health are complements. Competitive equilibria are first-best if lottery contracts are enforceable, but typically not if only assets with deterministic payoffs are traded. Compensating wage differentials which equalize the utilities of workers in different jobs are incompatible with ex-ante efficiency. Finally, absent asymmetric information, there exist deterministic cross-jobs transfers leading to ex-ante efficiency.compensating wage differentials, competitive markets, individual health risks, Pareto efficiency

Screening for health risks: A social science perspective

Health screening promises to reduce risks to individuals via probabilistic sifting of populations for medical conditions. The categorisation and selection of 'conditions' such as cardiovascular events, dementia and depression for screening itself requires prior interpretive labour which usually remains unexamined. Screening systems can take diverse organisational forms and varying relationships to health status, as when purported disease precursors, for example 'pre-cancerous' polyps, or supposed risk factors, such as high cholesterol themselves, become targets for screening. Screening at best yields small, although not necessarily unworthwhile, net population health gains. It also creates new risks, leaving some individuals worse-off than if they had been left alone. The difficulties associated with attempting to measure small net gains through randomised controlled trials are sometimes underestimated. Despite endemic doubts about its clinical utility, bibliometric analysis of published papers shows that responses to health risks are coming to be increasingly thought about in terms of screening. This shift is superimposed on a strengthening tendency to view health through the lens of risk. It merits further scrutiny as a societal phenomenon

Understanding Health Risks for Adolescents in Protective Custody

Children in child welfare protective custody (e.g., foster care) are known to have increased health concerns compared to children not in protective custody. The poor health documented for children in protective custody persists well into adulthood; young adults who emancipate from protective custody report poorer health, lower quality of life, and increased health risk behaviors compared to young adults in the general population. This includes increased mental health concerns, substance use, sexually transmitted infections, unintended pregnancy, and HIV diagnosis. Identifying youth in protective custody with mental health concerns, chronic medical conditions, and increased health risk behaviors while they remain in custody would provide the opportunity to target prevention and intervention efforts to curtail poor health outcomes while youth are still connected to health and social services. This study leveraged linked electronic health records and child welfare administrative records for 351 youth ages 15 and older to identify young people in custody who were experiencing mental health conditions, chronic medical conditions, and health risk behaviors (e.g., substance use, sexual risk). Results indicate that 41.6% of youth have a mental health diagnosis, with depression and behavior disorders most common. Additionally, 41.3% of youth experience chronic medical conditions, primarily allergies, obesity, and vision and hearing concerns. Finally, 39.6% of youth use substances and 37.0% engage in risky sexual behaviors. Predictors of health risks were examined. Those findings indicate that women, those with longer lengths of stay and more times in custody, and those in independent living and conjugate care settings are at greatest risk for mental health conditions, chronic medical conditions, and health risk behaviors. Results suggest a need to ensure that youth remain connected to health and mental health safety nets, with particular attention needed for adolescents in care for longer and/or those placed in non-family style settings. Understanding who is at risk is critical for developing interventions and policies to target youth who are most vulnerable for increased health concerns that can be implemented while they are in custody and are available to receive services

CONSUMER PERCEPTION OF HEALTH RISKS IN FOOD

Consumer/Household Economics, Food Consumption/Nutrition/Food Safety,

ECONOMIC IMPACT OF ENVIRONMENTAL HEALTH RISKS ON HOUSE VALUES IN SOUTHEAST REGION: A COUNTY-LEVEL ANALYSIS

A simultaneous model of house values, cancer mortality and total releases is simultaneously estimated to study effects of environmental health risks. Health risks include county level total releases, number of Superfund sites and cancer mortality in Southeastern U.S. Benefits of superfund cleanup and reduced releases are also estimated.Environmental Economics and Policy,

Health Risks From Mercury-Contaminated Fish: A Reassessment

Several Congressional bills and a pending EPA regulation would significantly cut mercury emissions from power plants, so as to reduce mercury-related neurological effects among children. There is, however, no estimate of the number of cases of neurological deficiencies that might be avoided by such emissions cuts. To inform policymakers, we develop estimates of the annual number of cases of neurodevelopmental effects among children in the United States, based on existing estimates of the exposure and dose-response relationships for prenatal exposure to methylmercury. Using data on emissions and deposition, we show that eliminating mercury emissions from U.S. power plants would prevent on the order of 10,000 cases of subtle neurological deficiencies per year. For a related paper, see Regulating Mercury Emissions: What Do We Know About Costs and Benefits?Environment, Health and Safety, Regulatory Reform