Houston officials have approved $5 million for a fund to help relocate residents from neighborhoods located near a rail yard polluted by a cancer-linked wood preservative that has been blamed for an increase in cancer cases.

Residents and local officials have long blamed the high number of cancer cases on contamination from a rail yard originally owned by Southern Pacific and later bought by Union Pacific near two historically Black neighborhoods, Fifth Ward and Kashmere Gardens. The wood preservative creosote, which has been associated with an increased risk of contracting cancer, was used for more than 80 years at the site until the 1980s. City officials say the contamination has reached the groundwater in the neighborhoods.

During a city council meeting in which the funding was approved, Mayor Sylvester Turner said Houston “has a moral obligation” to help relocate residents away from the four different cancer clusters that have been identified in recent years. Health officials have found higher rates of respiratory cancers as well as childhood cancers, including acute lymphoblastic leukemia.