title: Greater hemocyte bactericidal activity in oysters (Crassostrea virginica) from a relatively contaminated site in Pensacola Bay, Florida.
abstract: Bivalve mollusks such as Crassostrea virginica inhabiting polluted estuaries and coastal areas may bioaccumulate high concentrations of contaminants without apparent ill effects. However, changes in putative internal defense activities have been associated with contaminant accumulation in both experimental and long-term field exposures. In an effort to elucidate these relationships, 40 oysters were collected from Bayou Chico (BC) and East Bay (EB) in Pensacola Bay, FL, two estuaries known to differ in the type and magnitude of chemical contaminants present. Oyster tissue concentrations of metals, tri- and dibutyltin (TBT, DBT), polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) were measured in individual oysters, as were hemocyte counts (HCs), hemocyte bacterial killing indices (KI), serum lysozyme (LYS) and serum protein (PRO) levels. Average HC, KI, LYS and PRO were significantly higher in BC oysters, which also had significantly higher tissue concentrations of total trace metals, butyltins (BTs), PAHs, PCBs, pesticides, and Mn, Cu, Zn and Sn. EB oysters had low organic contaminant levels and no detectable BTs, but significantly higher concentrations of Al, Cr, Fe, Ag, Cd, and Hg. Simple correlation analysis between specific defense measurements and specific chemical analytes showed specific positive relationships that corroborated previous findings in other FL estuaries. Canonical correlation analysis was used to examine relationships between defense measurements and tissue metals using linearly combined sets of variables. Results were also consistent with previous findings-the highest possible canonical correlation was positive: r=0.864, P<0.0019 among canonical variables composed of HC, KI and LYS for defense, and Fe, Cu, Ag, Cd, Sb, Sn, Ni, Pb and Hg for metals.
authors.affiliation: US Environmental Protection Agency, National Health and Environmental Effects Research Laboratory, Gulf Breeze, FL 32561, USA.
authors.forename: Leah M
authors.initials: LM
authors.lastname: Oliver
authors.forename: William S
authors.initials: WS
authors.lastname: Fisher
authors.forename: Aswani K
authors.initials: AK
authors.lastname: Volety
authors.forename: Ziad
authors.initials: Z
authors.lastname: Malaeb
mesh_terms: D000818:Animals; D001770:Blood Bactericidal Activity / Q000187:drug effects*; D005431:Florida; D006434:Hemocytes / Q000187:drug effects* / Q000276:immunology*; D008670:Metals / Q000633:toxicity; D009113:Muramidase / Q000097:blood / Q000187:drug effects; D009930:Organic Chemicals / Q000633:toxicity; D009942:Organometallic Compounds / Q000633:toxicity; D009947:Organotin Compounds / Q000633:toxicity; D010125:Ostreidae / Q000276:immunology*; D011078:Polychlorinated Biphenyls / Q000633:toxicity*; D011084:Polycyclic Aromatic Hydrocarbons / Q000633:toxicity*; D012623:Seawater / Q000737:chemistry; D013223:Statistics as Topic; D014220:Trialkyltin Compounds / Q000633:toxicity; D014873:Water Pollutants / Q000633:toxicity*
chemical_list: D008670:Metals; D009930:Organic Chemicals; D009942:Organometallic Compounds; D009947:Organotin Compounds; D011084:Polycyclic Aromatic Hydrocarbons; D014220:Trialkyltin Compounds; D014873:Water Pollutants; C056189:di-n-butyltin; C011559:tributyltin; D011078:Polychlorinated Biphenyls; D009113:Muramidase