Development of failure scenarios for biosolids land application risk assessment.

Although deviations from standard guidance for land application of biosolids occur in practice, their importance is largely unknown. A list of such deviations (plausible failure scenarios) were identified at a workshop of industry, regulators, and academic professionals. Next, a survey of similar professionals was conducted to rank the plausible failure scenarios according to their severity, frequency, incentive to ignore control measures, gaps in existing control processes, public concern, and overall concern. Survey participants rated intentional dumping (unpermitted disposal) as the most severe of the failure scenarios, lack of worker protection as the most frequent scenario, and application of Class A biosolids that have failed to meet treatment standards as the scenario for which incentives to ignore control measures are highest. Failure of public access restrictions to application sites was the scenario for which existing controls were judged the weakest; application of biosolids too close to wells was ranked highest for public concern and for overall concern. Two scenarios for which existing controls were considered weaker, site restriction violations and animal contact leading to human exposure, were also rated as frequently occurring. Both scenarios are related in that they (1) involve inappropriate access to a site before the required time has elapsed, and (2) could be addressed through similar biosolids management measures.

Applying the mental models framework to carbon monoxide risk in northern Mexico.

OBJECTIVES: Low-income residents of northern Mexico rely on unvented heaters during the winter, a practice that puts them at elevated risk for carbon monoxide intoxication. The goal of this study is to develop a communication protocol for carbon monoxide intoxication risks among the primarily low socioeconomic status population of Ciudad Juárez, Chihuahua, Mexico. METHODS: The mental models risk communication approach was used to identify important gaps in public understanding. This approach consists of step-by-step assessment of information needs and effectiveness of risk communication efforts by using interviews and surveys. RESULTS: The mental models process uncovered a key technical misunderstanding, the subject population's belief that carbon monoxide can be seen or smelled, which may result in a risk-prone behavior: failure to use a carbon monoxide detector. A communication protocol was designed to address this and other knowledge gaps, and it produced significant improvements in subjects' knowledge in a pretest/posttest evaluation. CONCLUSIONS: The mental models process was successful in developing a communication instrument capable of improving knowledge in the subject population. Future research needs include assessing the extent to which this instrument succeeds in changing behavior and reducing the risk of carbon monoxide intoxication. Future interventional efforts may focus on encouraging people to use carbon monoxide detectors.

Applying the mental models framework to carbon monoxide risk in northern Mexico / Aplicación del enfoque de los modelos mentales al riesgo por monóxido de carbono en el norte de México

OBJECTIVES: Low-income residents of northern Mexico rely on unvented heaters during the winter, a practice that puts them at elevated risk for carbon monoxide intoxication. The goal of this study is to develop a communication protocol for carbon monoxide intoxication risks among the primarily low socioeconomic status population of Ciudad Juárez, Chihuahua, Mexico. METHODS: The mental models risk communication approach was used to identify important gaps in public understanding. This approach consists of step-by-step assessment of information needs and effectiveness of risk communication efforts by using interviews and surveys. RESULTS: The mental models process uncovered a key technical misunderstanding, the subject population's belief that carbon monoxide can be seen or smelled, which may result in a risk-prone behavior: failure to use a carbon monoxide detector. A communication protocol was designed to address this and other knowledge gaps, and it produced significant improvements in subjects' knowledge in a pretest/posttest evaluation. CONCLUSIONS: The mental models process was successful in developing a communication instrument capable of improving knowledge in the subject population. Future research needs include assessing the extent to which this instrument succeeds in changing behavior and reducing the risk of carbon monoxide intoxication. Future interventional efforts may focus on encouraging people to use carbon monoxide detectors.

OBJETIVOS: Los residentes de bajos ingresos del norte de México dependen durante el invierno de calefactores no ventilados, una práctica que los pone en mayor riesgo de intoxicación por monóxido de carbono. Se elaboró un protocolo de comunicación sobre los riesgos de intoxicación por monóxido de carbono en la población fundamentalmente de bajo nivel socioeconómico de Ciudad Juárez, Chihuahua, México. MÉTODOS: Se utilizó el enfoque de comunicación de riesgos de los modelos mentales para identificar importantes brechas en la comprensión pública. Este enfoque consiste en la evaluación paso a paso de las necesidades de información y la eficacia de los esfuerzos de comunicación de riesgos, mediante entrevistas y encuestas. RESULTADOS: El proceso basado en los modelos mentales descubrió un malentendido técnico clave: la población estudiada cree que el monóxido de carbono se puede ver u oler. Esto puede llevar a un comportamiento proclive al riesgo: no utilizar detectores de monóxido de carbono. Se diseñó un protocolo de comunicación para atender esta y otras brechas en el conocimiento que, según las evaluaciones previa y posterior, mejoró significativamente el nivel de conocimiento de las personas. CONCLUSIONES: El proceso basado en modelos mentales permitió desarrollar exitosamente un instrumento de comunicación capaz de mejorar el nivel de conocimiento en la población estudiada. Investigaciones futuras deben evaluar en qué grado este instrumento logra modificar el comportamiento y reducir el riesgo de intoxicación por monóxido de carbono. Nuevas intervenciones podrían centrarse en estimular el uso de detectores de monóxido de carbono.