This study focuses on children's understanding of hazardous household items (HHI) and waste (HHW). Children from grades 4, 5 and 6 (n=173) participated in a questionnaire and interview research design. The results indicate that: (a) on a daily basis the children used HHI and disposed of HHW, (b) the children did not realize the danger of these items and their exposure to hazardous substances, (c) some children ignore consequent adverse health effects, (d) school-based recycling and other environmental education programs can have a significant effect on children's conceptions, and (e) even though children use and discard HHI, they can also present a strong external environmental locus of control orientation, considering that others, and not they themselves, should deal with the problem. The findings enrich the knowledge base on the topic, and can be used in the development of "environmental" education pedagogies aimed at reducing environmental and health risks associated with the use and disposal of hazardous items. (Contains 1 note, 1 table, and 5 figures.)