Table of Contents: 1  INTRODUCTION, DEFINITION & VALUE OF RESEARCH. 2  SCIENTIFIC METHOD OF RESEARCH & ITS SPECIAL FEATURES. 3  CLASSIFICATION OF RESEARCH:Goals of Exploratory Research. 4  THEORY AND RESEARCH:Concepts, Propositions, Role of Theory. 5  CONCEPTS:Concepts are an Abstraction of Reality, Sources of Concepts.
Lead poisoning is a serious and sometimes fatal condition. It occurs when lead builds up in the body. Lead is a highly toxic metal and a very strong poison. It is found in lead-based paints, including paint on the walls of old houses and toys.
Lead is found in the mineral nagyagite, a sulfide, along with gold, iron, antimony, and tellurium. Silver joins with lead and antimony in the sulfide andorite, AgPbSb 3 S 6. Lead, copper and iron join in the sulfide betekhtinite. In the sulfide mineral hutchinsonite,(Tl, Pb) 2 As 5 S 9, lead joins with arsenic and thallium.