RUNOFF FROM COAL PILES: EFFECTS ON THE ENVIRONMENT AND THE PUBLIC'S HEALTH

The use of coal for fuel in place of oil and natural gas has been increasing in the United States. Typically, users store their reserves of coal outdoors in large piles and rainfall on the coal creates runoffs which may contain materials hazardous to the environment and the public's health. To study this hazard, rainfall on model coal piles was simulated, using deionized water and four coals of varying sulfur content. The simulated surface runoffs were collected during 9 rainfall simulations spaced 15 days apart. The runoffs were analyzed for 13 standard water quality parameters, extracted with organic solvents and then analyzed with capillary column GC/MS, and the extracts were tested for mutagenicity with the Ames Salmonella microsomal assay and for clastogenicity with Chinese hamster ovary cells.^ The runoffs from the high-sulfur coals and the lignite exhibited extremes of pH (acidity), specific conductance, chemical oxygen demand, and total suspended solids; the low-sulfur coal runoffs did not exhibit these extremes. Without treatment, effluents from these high-sulfur coals and lignite would not comply with federal water quality guidelines.^ Most extracts of the simulated surface runoffs contained at least 10 organic compounds including polycyclic aromatic hydrocarbons, their methyl and ethyl homologs, olefins, paraffins, and some terpenes. The concentrations of these compounds were generally less than 50 (mu)g/l in most extracts.^ Some of the extracts were weakly mutagenic and affected both a DNA-repair proficient and deficient Salmonella strain. The addition of S9 decreased the effect significantly. Extracts of runoffs from the low-sulfur coal were not mutagenic.^ All extracts were clastogenic. Extracts of runoffs from the high-sulfur coals were both clastogenic and cytotoxic; those from the low-sulfur coal and the lignite were less clastogenic and not cytotoxic. Clastogenicity occurred with and without S9 activation. Chromosomal lesions included gaps, breaks and exchanges. These data suggest a relationship between the sulfur content of a coal, its mutagenicity and also its clastogenicity.^ The runoffs from actual coal piles should be investigated for possible genotoxic effects in view of the data presented in this study.^

Assessing fun in serious games: Formative evaluation of games from two diabetes prevention interventions

Purpose. To determine the usability of two video games to prevent type 2 diabetes and obesity among youth through analysis of data collected during alpha-testing. ^ Subjects. Ten children aged 9 to 12 were selected for three 2-hour alpha testing sessions.^ Methods. "Escape from Diab" and "Nanoswarm" were designed to change dietary and physical inactivity behaviors, based on a theoretical framework of mediating variables obtained from social cognitive theory, self-determination theory, elaboration likelihood model, and behavioral inoculation theory. Thirteen mini-games developed by the software company were divided into 3 groups based on completion date. Children tested 4-5 mini-games in each of three sessions. Observed game play was followed by a scripted interview. Results from observation forms and interview transcripts were tabulated and coded to determine usability. Suggestions for game modifications were delivered to the software design firm, and a follow-up table reports rationale for inclusion or exclusion of such modifications.^ Results. Participants were 50% frequent video game players and 20% non game-players. Most (60%) were female. The mean grade (indicating likeability as a subset of usability) across all games given by children was significantly greater than a neutral grade of 80% (89%, p < 0.01), indicating a positive likeability score. The games on average also received positive ratings for fun, helpfulness of instructions and length compared to neutral values (midpoint on likert scales) (all p < 0.01). Observation notes indicated that participants paid attention to the instructions, did not appear to have much difficulty with the games, and were "not frustrated", "not bored", "very engaged", "not fidgety" and "very calm" (all p < 0.01). The primary issues noted in observations and interviews were unclear instructions and unclear purpose of some games. Player suggestions primarily involved ways to make on screen cues more visible or noticeable, instructions more clear, and games more elaborate or difficult.^ Conclusions. The present study highlights the importance of alpha testing video game components for usability prior to completion to enhance usability and likeability. Results indicate that creating clear instructions, making peripheral screen cues more eye-catching or noticeable, and vigorously stating the purpose of the game to improve understandability are important elements. However, future interventions will each present unique materials and user-interfaces and should therefore also be thoroughly alpha-tested. ^