Related by context. Frequent words. (Click for all words.) 62 aquatic organisms 61 Hydrogen sulfide 60 microscopic algae 60 odorless colorless gas 58 Algae blooms 58 plankton blooms 58 toxic algae blooms 57 phytoplankton blooms 57 filter feeders 57 upwellings 57 contaminate drinking 57 Phytoplankton 57 Cyanobacteria 56 plankton 56 bioaccumulation 56 oxygen depletion 56 microscopic plankton 56 naturally occurring bacteria 56 algae blooms 55 clog arteries 54 planktonic 54 phytoplankton 54 bioaccumulate 54 Nitrogen oxides 54 Sulfur dioxide 54 aquatic ecosystems 54 organisms 54 mold fungi 53 marine organisms 53 zooplankton 53 potent neurotoxin 53 absorbing carbon dioxide 53 Diesel exhaust 53 microorganisms 53 oxygen starved 53 chloride ions 53 harmful algal blooms 53 rotting vegetation 53 Melting glaciers 53 copepods 53 river deltas 52 algal blooms 52 bacteria 52 pollutants 52 polycyclic aromatic hydrocarbons PAHs 52 absorb carbon dioxide 52 e mail EveningStarLetters@eveningstar.co.uk 52 algae 52 dissolved oxygen 52 acidifying 52 acidification 52 crabs shrimp 52 Pollutants 52 microscopic organisms 52 ocean ecosystems 52 contaminants 52 contaminate groundwater 52 seagrasses 52 incomplete combustion 51 methane 51 nutrient rich 51 aquatic ecosystem 51 animal dander 51 intertidal zone 51 micro organisms 51 methyl mercury 51 aggravate asthma 51 algal 51 microbes 51 Soil erosion 51 photosynthesize 51 toxins 51 biota 51 nutrient absorption 51 acrolein 51 benthic 51 harmful microorganisms 51 freshwater mussels 51 dissolved oxygen levels 51 Toxic chemicals 50 bacteria fungi 50 underwater grasses 50 Acidity 50 nutrient runoff 50 carbonic acid 50 absorb nutrients 50 toxicants 50 marine ecosystems 50 adenosine triphosphate ATP 50 terrestrial ecosystems 50 Stormwater runoff 50 oxidize 50 Dust mites 50 sequester carbon dioxide 50 combustible gases 50 Ultraviolet light 50 atmospheric nitrogen 50 unsaturated fatty acids 50 creeks streams 50 harmful contaminants 50 aquatic invertebrates