title: Bioaccumulation surveillance in Milford Haven Waterway.
abstract: Biomonitoring of contaminants (metals, organotins, polyaromatic hydrocarbons (PAHs), PCBs) was undertaken in Milford Haven Waterway (MHW) and a reference site in the Tywi Estuary (St Ishmael/Ferryside) during 2007-2008. Bioindicator species encompassed various uptake routes-Fucus vesiculosus (dissolved contaminants); Littorina littorea (grazer); Mytilus edulis and Cerastoderma edule (suspension feeders); and Hediste (=Nereis) diversicolor (sediments). Differences in feeding and habitat preference have subtle implications for bioaccumulation trends though, with few exceptions, contaminant burdens in MHW were higher than the Tywi reference site, reflecting inputs. Elevated metal concentrations were observed at some MHW sites, whilst As and Se (molluscs and seaweed) were consistently at the higher end of the UK range. However, for most metals, distributions in MH biota were not exceptional. Several metal-species combinations indicated increases in bioavailability upstream, which may reflect the influence of geogenic/land-based sources-perhaps enhanced by lower salinity. TBT levels in MH mussels were below OSPAR toxicity thresholds and in the Tywi were close to zero. Phenyltins were not accumulated appreciably in M. edulis, whereas some H. diversicolor populations appear subjected to localized (historical) sources. PAHs in H. diversicolor were distributed evenly across most of MHW, although acenaphthene, fluoranthene, pyrene, benzo(a)anthracene and chrysene were highest at one site near the mouth; naphthalenes in H. diversicolor were enriched in the mid-upper Haven (a pattern seen in M. edulis for most PAHs). Whilst PAH (and PCB) concentrations in MH mussels were mostly above reference and OSPAR backgrounds, they are unlikely to exceed ecotoxicological thresholds. Bivalve Condition indices (CI) were highest at the Tywi reference site and at the seaward end of MH, decreasing upstream-giving rise to several significant (negative) relationships between CI and body burdens. Despite the possible influence of salinity gradient as a complicating factor, multivariate analysis indicated that a combination of contaminants could influence the pattern in condition (and the biomarkers metallothionein and TOSC). Integrating bioaccumulation data with biological and biochemical endpoints is seen as a useful way to discriminate environmental quality of moderately contaminated areas such as MHW and to prioritise cause and effect investigations.
authors: Marine Biological Association, Citadel Hill, Plymouth PL1 2PB, UK. wjl@mba.ac.uk
authors: W J
authors: WJ
authors: Langston
authors: S
authors: S
authors: O'Hara
authors: N D
authors: ND
authors: Pope
authors: M
authors: M
authors: Davey
authors: E
authors: E
authors: Shortridge
authors: M
authors: M
authors: Imamura
authors: H
authors: H
authors: Harino
authors: A
authors: A
authors: Kim
authors: C H
authors: CH
authors: Vane
mesh_terms: D000818:Animals; D015415:Biomarkers; D004784:Environmental Monitoring / Q000379:methods*; D019015:Geologic Sediments; D007448:Invertebrates / Q000737:chemistry* / Q000378:metabolism; D008670:Metals / Q000737:chemistry* / Q000378:metabolism; D009947:Organotin Compounds / Q000737:chemistry / Q000378:metabolism; D006113:United Kingdom; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000378:metabolism
chemical_list: D015415:Biomarkers; D008670:Metals; D009947:Organotin Compounds; D014874:Water Pollutants, Chemical