Many areas are dealing with heavy metal pollution and the effect this pollution has on the environment. Much of this pollution results from mining and industrial production. A particular area of concern is heavy metals in aquatic ecosystems. High levels of heavy metal exposure can affect aquatic organisms and in some cases lead to death. These metals can also have human health effects. This study will evaluate if acanthocephalans can serve as a bioindicator for heavy metal pollution. Acanthocephalans, or spiny-headed worms, are endo-parasites that have complex life cycles. Current research suggests that acanthocephalans can serve as bioindicators for heavy metals in aquatic ecosystems because of their ability to accumulate heavy metals. Acanthocephalans used in this study were from two groups of Harbor seals off the Pacific coast of Oregon, one near the opening of the polluted Columbia River and another group of seals upcoast from the river. Selected acanthocephalans were digested in nitric acid (HNO3) and zinc, lead, and arsenic concentrations were measured using an atomic absorbance spectrophotometer. We hypothesize that there will be a detectable difference in heavy metals between these two groups of seals. If seals closer to the opening of the river have parasites with higher concentrations of heavy metals than parasites from seals farther away, this could indicate relative pollution in the area and offer support for using acanthocephalans as bioindicators for heavy metals. Having reliable bioindicators is important because monitoring these heavy metals are crucial for ecosystem health as well as public health.