Impacts of metal mining on river systems: a global assessment.

An estimated 23 million people live on floodplains affected by potentially dangerous concentrations of toxic waste derived from past and present metal mining activity. We analyzed the global dimensions of this hazard, particularly in regard to lead, zinc, copper, and arsenic, using a georeferenced global database detailing all known metal mining sites and intact and failed tailings storage facilities. We then used process-based and empirically tested modeling to produce a global assessment of metal mining contamination in river systems and the numbers of human populations and livestock exposed. Worldwide, metal mines affect 479,200 kilometers of river channels and 164,000 square kilometers of floodplains. The number of people exposed to contamination sourced from long-term discharge of mining waste into rivers is almost 50 times greater than the number directly affected by tailings dam failures.

A closer look at self-image in male foster care adolescents.

Using the Offer Self-Image Questionnaire, this study attempted to determine the differences between 58 male adolescents in foster care and their peers in the normal population and to establish if there are characteristics of the adolescents' background or foster care experience related to specific domains of self-image. Characteristics from foster care history included number of placements and length of time at the current placement. Individual background characteristics included race, educational achievement, and age. Foster care youths had lower family self-image and emotional health and higher social self-image when compared with the normative population. Lower scores on several domains of self-image were associated with being younger, being white, having lower academic achievement, having more placements, and staying at the current placement for a longer time. The implications of these findings for foster care placement decisions are discussed.

A photographic method of diet evaluation.

A photographic method of diet assessment is described. The subject is issued with a camera and a food record book and asked to photograph all meals and record the number of the photograph and details which will not show in photographs such as the method of cooking, the use of sugar in drinks, etc. The photographs are viewed alongside previously prepared 'standard' slides which show the weights of a variety of portions of each foodstuff. A weight is given to each item and nutrient analysis is done with food composition tables. The cost of the camera is comparable to the cost of a weighing scale and the cost of film is about pounds 6 (+9) per subject per week.