Abundance and distribution of beach litter with acutely toxic metal concentrations

Abstract

We determined if colour, category (e.g., food packaging) or intertidal activity could explain the occurrence of litter with acute levels of metals. Six beaches were sampled; an industrial site, a local and remote park and three beaches. Food packaging accounted for 66% of litter with acute levels of metals found in 10% of samples. Acute levels were independent of colour and category, but dependent on intertidal region and its anthropogenic use. Litter with acute levels of cadmium and lead were recovered from the industrial intertidal and high concentrations of zinc and cadmium associated with candy wrappers were found on recreational beaches. In addition to the intrinsic and extrinsic loads that litter carries, also too are memory effects, i.e., the previous use of the item carries over its trace metal burden posing extreme risks to marine ecosystems. In the managing of risk associated with beach litter, legacy contaminants need be considered.