what are some environmental hazards they are susceptible to?
Plastic waste flotsam, damaged ozone layer, and ocean acidification.
Cetacea
Heavy metals, residues of many plant and insect venoms and plastic waste flotsam are not biodegradable. Sometimes, cetaceans consume these hazardous materials, mistaking them for food items. As a result, the animals are more susceptible to disease and have fewer offspring.

Damage to the ozone layer reduces plankton reproduction because of its resulting radiation. This shrinks the food supply for many marine animals, but the filter-feeding baleen whales are most impacted. Even the Nekton is, in addition to intensive exploitation, damaged by the radiation.

Food supplies are also reduced long-term by ocean acidification due to increased absorption of increased atmospheric carbon dioxide. The CO reacts with water to form carbonic acid, which reduces the construction of the calcium carbonate skeletons of food supplies for zooplankton that baleen whales depend on.
what is baleen whale? A parvorder of the infraorder Cetacea. what is the lifespan of the latter mentioned? Over 200 years. what is the head like of these species? Elongated head how intelligent are they? Known to teach, learn, cooperate, scheme and grieve.
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Cetacea [SEP] Environmental hazards
Heavy metals, residues of many plant and insect venoms and plastic waste flotsam are not biodegradable. Sometimes, cetaceans consume these hazardous materials, mistaking them for food items. As a result, the animals are more susceptible to disease and have fewer offspring. Damage to the ozone layer reduces plankton reproduction because of its resulting radiation. This shrinks the food supply for many marine animals, but the filter-feeding baleen whales are most impacted. Even the Nekton is, in addition to intensive exploitation, damaged by the radiation. Food supplies are also reduced long-term by ocean acidification due to increased absorption of increased atmospheric carbon dioxide.