Release of PAHs and heavy metals in coastal environments linked to leisure boats.

Leisure boats are responsible for elevated levels of heavy metals and PAHs in sediments in- and near marinas and natural harbours. As these compounds are released directly into the water column they also pose a threat to organisms in the pelagic environment. Passive samplers were deployed during peak and post tourist season in the water column of natural harbours, leisure boat waterways and small marinas to measure the dissolved fraction of PAHs and metal ions. Differences between seasons indicative of leisure boat activities were found as PAH composition differed between peak and post season for natural harbours and waterways, where heavier PAHs increased during peak season. During peak season, metal samplers were covered by biofouling, which likely affected the uptake. Post season metal concentrations differ between locations, with concentrations exceeding quality standards at near mainland locations where boats are maintained, compared to the sites in the archipelago.