I like to look on the positive side, so let me reassure you that there's no evidence your bottled water has cyanide.
Arsenic? Well ... that's a different matter. Bottled water may have unsafe levels of arsenic, said one headline discussing a new Consumer Reports study. They tested 130 brands, and found that 11 had "unsafe" levels of arsenic. To which any sensible person asks: There is a safe level of arsenic?
Well, yes! If you're a 19th-century doctor with bushy whiskers who tut-tuts at patients and says, "It's nothing but a mild case of liver fog" because your profession is still groping around in the dark. Arsenic was used as a medicine in small doses, perhaps because people treated with the stuff were usually symptom-free within a week, which is to say, dead.
If you wanted to poison a spouse, arsenic was the way to go. It built up over time, gave people horrible stomachaches that the doctors of the day would diagnose as "hysterical gastritis" or "exhausted colon." It fell from favor when actual medicine was invented, and people stopped rubbing lead paste on babies to cure colic.
Most of us grew up in fear of arsenic. Perhaps Grandma had a rusty tin of the stuff in the cellar, which she used to kill rats or perhaps cure their syphilis. The container had a skull and crossbones, and no kid thought that meant "magic powder that turns you into a pirate."
The only thing worse was cyanide. We believed all Nazi spies had a secret tooth filled with cyanide so they could bite down if captured and die sneering. Given the number of times I bite my own cheek while just trying to eat, this seems an unwise strategy.
Anyway. Federal regulations do not ban arsenic from bottled water. It can contain up to 10 parts per billion, which means nothing to anyone. Consumer Reports says some scientists say 3 ppb should be the actual standard, but these are probably the killjoys who say you shouldn't eat bacon three times a day.
One of the brands that Consumer Reports criticized for having over 3 ppb was "Crystal Geyser Alpine Spring Water," which in retrospect seems to be overcompensating. A Whole Foods brand, Starkey, also had over 3 ppb. To be honest, "starkey" sounds like a word you'd use to describe water that tasted a bit off, but you couldn't say why. "Ew — this water, it's, I don't know, a bit starkey."
