Beachgoers in San Diego may have spotted some glistening, purple shells reminiscent of small gemstones in the sand recently.

The answer, unfortunately, is often waterways, where the tiny microplastic particles from the tires’ synthetic rubber carry several chemicals that can transfer into fish, crabs and perhaps even the ...

• Pack a few familiar comforts. Charlie never travels without a half-dozen of his favorite squeaky toys. A cozy bed, treats ...