Some believe Romans from the period around 150 b.c.e. may have been victims of lead poisoning. Symptoms of lead poisoning include sterility, general weakness, apathy, mental retardation, and early death. The lead could have been ingested in water taken from lead-lined water pipes or from food cooked in their lead-lined cooking pots or from wine served in lead-lined goblets. Unaware of its dangers, some ancient Romans unwittingly used lead as a sweetening agent or medical treatment for diarrhea. Lead poisoning could have caused infertility in women, leading to a subsequent long-term decline in the birth rate of the Roman upper classes. The effect of this inadvertent toxic food additive on Roman history, however, is only speculative.