Food safety caution for River Derwent anglers

Recreational fishers in the River Derwent have been warned against eating certain fish and shellfish due to heavy metal contamination by the Director of Public Health, in a recent 'Should I eat shellfish and fish from the Derwent' brochure produced by the Derwent Estuary Program (DEP).  The brochure recommends that anglers should not eat ANY shellfish or bream from the River Derwent (including Ralphs Bay and Browns River), and to limit their consumption of flathead and other Derwent-caught fish such as brown trout to once a week.

The River Derwent is a very popular recreational fishery which has an excellent reputation for bream and sea run trout. The problem is that heavy metals have accumulated in sediment as a result of industry pollution in the past. These contaminants are passed on through the food chain and result in levels that make certain fish species unsafe to eat.

Routine monitoring of heavy metal levels in oysters, mussels and flathead has continued for many years. Oysters and mussels contain high levels of zinc, lead and cadmium – well above safe levels – while the mercury levels in flathead have typically been near or slightly above food safety standards. After elevated mercury levels were identified in bream and estuary caught trout in 2007, the monitoring of heavy metals in fish was extended to include other recreationally targeted species.

The Derwent Estuary Program is a regional partnership between local governments, the Tasmanian state government, commercial and industrial enterprises, and community-based groups to restore and promote our estuary.

The recent work by the DEP on heavy metal contamination in seafood in the River Derwent was funded through a Federal Government Caring for our Country grant, and supported by TARFish, Inland Fisheries Service, Fishcare, Institute of Marine and Antarctic Studies, Department of Health and Human Services and Analytical Services Tasmania.