Input of polynuclear aromatic hydrocarbons to San Diego Bay from creosote pier pilings

Describes recent measurements of the flux of polynuclear aromatic hydrocarbons (PAH) off of creosote impregnated pier pilings. The measurements were made in situ using a chamber attached directly to pier pilings in San Diego Bay, California. The flux into seawater was monitored using a flow-through ultra-violet (UV) fluorescence technique that was calibrated against discrete chamber samples analyzed for 36 individual PAH compounds. The flux rates calculated from these in situ measurements were 0.0022-0.0033 g PAH cm^-2 yr^-1. Based on a the total piling surface area available, the mass loading to the bay was estimated at 3-5 mt PAH yr^-1. A strong relationship was found between the spatial distribution of seawater PAH concentration and the general location of pilings in the bay. Compositional analysis of the PAH compounds found in bay seawater with those in creosote and those found in the flux experiment support the conclusion that creosote pilings are a significant source of PAH loading to San Diego Bay