Initial estimate of sediment toxicants beyond estuary mouths in - PowerPoint PPT Presentation

Initial estimate of sediment toxicants beyond estuary mouths in Western Port Vincent Pettigrove, Simon Sharp & Jackie Myers Centre for Aquatic Pollution Identification and Management (CAPIM) Toxicants in sediments: a screening study

Key Recommendation from review

Previous Research

Toxicants in sediments Toxicants Toxicant “Chemical pollutant that can have toxic effects on biota” 1 Heavy metals – above “natural” levels Petroleum Hydrocarbons – also occur naturally Pesticides – synthetic agriculture chemicals Antifoulant paints – tributyltin (historical) 1- ANZECC & ARMCANZ (2000) Australian and New Zealand guidelines for fresh and marine water quality. National Water Quality Management Strategy. Australia and New Zealand Environmental and Conservation Council & Agriculture and Research and Management Council of Australia and New Zealand.

Previous reports Inflows – freshwaters and estuaries Western Port Bay 3 1 2 4 Trace metals in Western Port sediments : final report P.J. Statham December 1977 Marine Chemistry Unit, Ministry for Conservation 1 - Rees et al (1998) Toxicants in Western Port sediments. Report to EPA Victoria 2 – Statham (1977) Trace metals in Western Port sediments: final report. Marine chemistry unit, Ministry for Conservation 3 – Hardwick (1998) Waterway assessment for the Western Port catchment: the environmental health of Western Port Peninsula Streams. 4 – Coleman & Pettigrove (2001) Waterway assessment in the Western Port catchment. The health of the Lang Lang River. Melbourne Water

Toxicants in Western Port sediments Sampling based on previous reports: Heavy metals 1,5 Organic pesticides 2,5,6 Petroleum hydrocarbons 1,5,7 Tributyltin from antifouling paint residues 1,4 1 - Rees et al (1998) Toxicants in Western Port sediments. Report to EPA Victoria 2 – Hardwick (1998) Waterway assessment for the Western Port catchment: the environmental health of Western Port Peninsula Streams. 3 – Coleman & Pettigrove (2001) Waterway assessment in the Western Port catchment. The health of the Lang Lang River. Melbourne Water 4 – Daly & Fabris (1993) An environmental study of tributyltin in Victorian waters. EPA Victoria. 5 – CAPIM (2012) Unpublished data 6 – Melbourne Water (2008) Unpublished data 7 – Burns, K. & Smith, J. 1977. Distribution of Petroleum Hydrocarbons in Westernport Bay (Australia): Results of Chronic Low Level Inputs.

Current Toxicant Study

Toxicants in sediments Study Objectives 1) Assess concentrations of toxicants with guidelines, 2) Determine patterns or possible sources of toxicants, 3) Compare concentrations of toxicants over time.

Study sites 42 Estuarine, freshwater and bay sites sampled during the study

Sampling Methodology Sediment grab samples collected by wader and boat • Filtered (<0.063 mm) to reduce variability • Analysis: • • Heavy metals, • Total organic carbon (TOC), 42 sites • Total petroleum hydrocarbons (TPHs), • Grain Size, 22 sites • Pesticides • Tributyltin and organotins (TBT) 7 sites

Estimating ecological threats from toxicants Concentrations in sediments were compared to the Interim Sediment Quality Guideline (ISQG) values (low) for 1 : Heavy metals • Pesticides (Organochlorine only) • Tributyltin • Proposed sediment quality guidelines for 2 : Total petroleum hydrocarbons (TPH) 1- ANZECC & ARMCANZ (2000) Australian and New Zealand guidelines for fresh and marine water quality. National Water Quality Management Strategy. Australia and New Zealand Environmental and Conservation Council & Agriculture and Research and Management Council of Australia and New Zealand. 2 – Simpson et al (2010) Revision of the ANZECC/ARMCANZ sediment quality guidelines. CSIRO Land and Water Science Report 08/07.

Research findings

Heavy Metals in Western Port Low concentrations at all sites: Metals a : Cadmium* • Chromium* • Copper* • Lead* • Zinc* • compared with Metals a ISQG-low values

Heavy Metals: Arsenic Moderate concentrations at various sites: Arsenic compared with ISQG-low values Slightly higher concentrations than 1997

Heavy Metals: Mercury Moderate concentrations at various sites: Mercury compared with ISQG-low values Slightly higher concentrations than 1997

Heavy Metals: Nickel Moderate concentrations at various sites: Nickel compared with ISQG-low values

Heavy Metals: Nickel Moderate concentrations at various sites: Nickel compared with ISQG-low values No apparent changes in concentrations

Petroleum Hydrocarbons (TPH) in Western Port Below threshold (275 mg/ kg) Maximum - 133 mg/ kg Proposed threshold concentration 1 – 275 mg/ kg 1- Simpson et al (2010) Revision of the ANZECC/ARMCANZ sediment quality guidelines. CSIRO Land and Water Science Report 08/07.

Petroleum Hydrocarbons (TPH) in Western Port No substantial increase over time 2 1 1- Burns & Smith (1977) Distribution of Petroleum Hydrocarbons in Westernport Bay. In: Wolfe (Ed.) Fate and Effects of Petroleum Hydrocarbons in Marine Organisms and Ecosystems. 2 – Rees et al (1998) Toxicants in Western Port sediments. MAFRI, Report to EPA Victoria.

Pesticide residues in Western Port No pesticide residues detected in sediments in the bay Moderate concentrations of pesticides in estuaries and freshwaters

Pesticide residues: mode of action Pesticide modes of action Substantial concentrations of herbicides and fungicides Low concentrations of insecticides – primarily residues of organochlorines

Tributyltin in Western Port Hastings Warneet Concentrations in sediments near heavy boating areas Substantially lower concentrations than 1988 and 1997 Two concentrations still above ISQG low

Sources of toxicants Discussion of findings

Heavy Metals entering waterways Primary sources of heavy metals in marine environments 1 : urban run-off (stormwater and base flows) • industrial effluents • Historical activities (mining, landfill, development) • atmospheric deposition (including dust) • agricultural activity • groundwater • 1 - Haynes and Johnson (2000) Marine Pollution Bulletin , 41, 267-278

Mornington Peninsula Cainozoic sands had naturally high levels of arsenic Soil types across greater Melbourne and soil sampling sites (  ) 1 1 - Pettigrove & Hoffmann (2003) Australasian Journal of Ecotoxicology, 9, 119-128

Organic toxicants entering waterways Pathways that organic toxicants (TPHs, pesticides) can enter waterways: Surface run-off, - Groundwater, - Exposure pathways for organic toxicants 1 Spray-drift, - Soil erosion, - Leaching from boat hulls, - Atmospheric deposition, - Spills. - 1 – Keough & Bathgate (2011) Threats and exposure pathways. In: Understanding the Western Port environment: A summary of current knowledge and priorities for future research. Melbourne Water.

Organic toxicants entering waterways Pesticides often used in intensive agriculture. Loosely bound soils and higher run-off rates

Estimating ecological threats from toxicants No guidelines for many new and emerging pesticides - Insecticides (pyrethroids, carbamates) - Herbicides - Fungicides Need for ecotoxicology experiments

Why Manage Toxicants? Potential decline in freshwater, estuarine and marine ecosystems - Herbicides: impacts on marine plants 1 and algae 2 - Metals: impacts on marine flora 3 and fauna 4 - Organotins: imposex in shellfish 5 - Petroleum Hydrocarbons: stress in biota 6,7 1 – Haynes et al (2000) Marine Pollution Bulletin, 41, 288 - 293 2 – Jansen & Altenburger Estuarine, Coastal and Shelf Science 62 (2005) 539 – 545 3 – MacInnes & Ralph (2004) Journal of Experimental Marine Biology and Ecology, 302, 63-83 4 – Simpson et al (2012) Environmental Science & Technology, 46, 9038-9046 5 – Rees et al (2001) Marine Pollution Bulletin, 42, 873-878 6 – Brils et al (2002) Environmental Toxicology and Chemistry, 21, 2242 - 2251 7 – Pettigrove & Hofman (2005) Environmental Toxicology and Chemistry, 24, 2500-2508

Key Recommendations Priority Recommendations: 1. Investigation of herbicides and fungicides in estuaries and mudflats of western port to understand risk posed to resident biota. 2. Conduct ecotoxicity tests with local flora to derive concentration thresholds for herbicides

Key Recommendations Secondary Recommendations: 1. Continue with the existing sediment quality monitoring program at key estuarine sites to monitor toxicants entering the bay, 2. Determine if sites where elevated concentrations of metals (arsenic, nickel and mercury), organotins and TPHs were detected are having ecological effects, 3. Monitor concentrations of metals in waters from waterways entering Western Port.

Cattle grazing near Cape Flinders, Mornington Peninsula Further investigations Pesticides im pacts on m arine organism s

Investigate Pesticide Concentrations in Western Port New monitoring program in Western Port Objective: • Determine if herbicides are likely to be impacting aquatic flora in Western Port. Aims: • Determine spatial and temporal variability of key herbicides in sediments and waters within Western Port. • Conduct ecotoxicology experiments to determine if key flora species are likely to be impacted by herbicides