The (0) ____ proliferation of microplastics throughout the world's oceans has hardened into an environmental crisis of staggering proportions. These insidious particles, more often than not invisible without the use of a microscope, have infiltrated even the deepest trenches on the planet. From Arctic sea ice to the sediment of the Mariana Trench, virtually no corner of the marine world has been left untouched. What renders the phenomenon so alarming is the sheer (1) ____ to which marine life is unwittingly consuming these toxins, which are already working their way into the human food chain, (2) ____ the long-term health consequences remain anyone's guess.

It scarcely needs (3) ____ at this point that nothing (4) ____ of a radical overhaul of our consumption habits will halt the damage. Consumers must wean themselves off the cheap, single-use packaging on which modern retail depends. That said, sporadic individual gestures will never do the trick on their own; governments must legislate, and legislate boldly. Had we grasped the ecological perils a generation ago, the worst of this slow-motion disaster might have been averted altogether. As things stand, scouring the oceans clean is out of the question. Prevention, most scientists now agree, is the only battle we still stand a realistic chance of winning.