Detection of waterborne mutagens in selected Galveston Bay sites

Blue cotton and blue rayon (either cotton or rayon with covalently linked copper phthalocyanine trisulfonate, a blue pigment) are reported to bind polycyclic aromatic compounds preferentially. Many of these polycyclic compounds are mutagenic and often carcinogenic. The objective of this study was to determine if there was a correlation between mutagenicity of blue-rayon-adsorbed compounds and the level of known mutagens detected in water samples from the same site. Several sites in Galveston Bay were sampled five or six days after 500000 gallons of oil had spilled into Galveston Bay in the summer of 1990. Blue rayon (1 g) was suspended in the water at a depth of 1-2 feet from the surface for 24 hours. Water samples were taken immediately prior to placing the blue rayon in the water. The blue rayon was removed and extracted with a methanol-ammonia solution. The extracts were assayed with Salmonella typhymurium TA98 in the presence of S9-mix. Mutagenicity, i.e. the number of revertants per plate, was directly correlated with the blue-rayon equivalents per plate. Blue rayon from areas in close proximity to the spill site had a higher mutagenic response than blue rayon from more distant sites. Attempts will be made to correlate the mutagenic response of the blue-rayon extracts with the presence of known mutagens in the water.