Effects of Dispersant Use on Shore Life
SourceDamage to Cornish seashore life resulting from the chemical dispersal of oil spilled from Torrey Canyon is often taken as typical of dispersant use, although primitive mixtures were badly misapplied there. Where more modern dispersants are used with care, as in recent Milford Haven spills, serious consequences can be avoided. All effective dispersants offer some biological hazards, especially to sedentary or planktonic filter-feeding animals, which are not revealed by short-term acute toxicity testing. Spilled oil should therefore be removed mechanically wherever possible. Careful spraying is recommended to prevent an oil slick reaching the shore and to protect seabird colonies. It may also be necessary on rocky or built-up amenity areas but should be avoided on coasts rarely visited by humans and distant from bird colonies. Spraying may worsen matters on sandy shores, while any form of treatment will further damage oiled salt marshes.