Lead in drinking water can cause serious health issues; Children/babies exposed to lead in drinking water above a certain level can result in poor physical/mental development in attention span and learning abilities. In adults, it can increase blood pressure or kidney failure (Minnesota Department of health).
Research has demonstrated health risks from manganese in drinking water. For example, manganese can adversely affect child intellectual function, and in large doses act as a neurotoxin causing symptoms similar to Parkinson’s disease (Connecticut Dept. of Health: fact sheet manganese in drinking water).
Metals are crucial elements for maintaining overall good health and transmitting electrical transmitters to/from the brain, but surpassing the required amount the body needs can have devastating consequences. Spraying manganese and lead in poverty neighborhoods are one of many scenarios that occur in the United States, the behaviors and killing being watched on most newscasts may not be a result of individual motives but rather manganese overdose.