Did you know breathing oxygen literally rusts us from the inside out and that is why we're not immortal?
But really. I don't think it's that big of a deal. I bet the poisons are in such a small trace it's nothing.
OMG my chemistry teacher used to tell that to us too! We're oxidising as we breath in oxygen. Can you imagine drinking a sip of OJ for every whiff of a pony you take to balance out? lol
Even natural items contain poisons. Apple seeds contain cynide but you need to eat like 60 apples worth of seeds all at once before you can drop dead. lol I am not that hardcore, so if I want to die, I'll pick something less grueling compared to forcing myself to down 60 apples at once. I guess the same goes to PVC. You'll probably need to actively chew and ingest ponies regularly for the next 2-5 days before you die from kidney and liver failure. Or whiff them 56 times a day for 2 years before you get nose cancer, and each whiff must be taken with a deep breath in with nostrils suctioned to the plastic creating a vacuum in between.
From a parenting point of view, I can see that it's good not to let your guard down because anything can be potentially harmful for the young and tender. They are curious and they often do the most unimaginable things once your eyes are not fixed on them. I would be wary about PVC causing possible harm, but it definitely wouldn't be top of the list. There are SO MANY other things to watch out for, like my niece has a penchant for stuffing things into her nose and once she almost did it with a screw! Even without phthalates, the screw was a much bigger hazard to any young child than a plastic pony I feel.
The next most harmful thing I feel isn't PVC but SUGAR. There're a lot more kids down with diebetes compared to the generation I grew up with when we had limited pocket money to buy junk food. Your child can be exposed to PVC for the next 20-30 years before any side effects start to show, but with all the sweet foods, you can easily see the terrible effects of diebetes on kids in less than a generation.
I'm not saying your fears are unfounded, but if it takes 30-50 years for PVC to show any symptom, well... most people would have grown up or been dead by then. Not to mention, there are probably deadlier chemicals that can kill you off within that 30-50 years while waiting for dioxins to finally take effect. You are better off worrying about if there are melamine in your milk powder or abestos in your toothpaste.
Point is given the extensive list of murderous "invisible" killers we have today, PVC actually needs to take a number and wait at the bottom of the list before it gets a chance to take your life or cause harm in a significant way. Like someone said, there are bigger fish to fry -once you can take out the "big boys" like I don't know... car fumes, carbon emissions, radiation from phones and machines, mercury from leaking batteries...etc - yeah, then go on to focus on the less offensive stuff like...PVC.
I actually note a higher problem with plastics around food rather than toys, because I see a lot of restaurants microwaving or cooking foods with their plastic packaging still on. That is actually extremely TOXIC because the plastic packagings are exposed to high heat together with the food, and you don't know if any chemical reaction had taken place or how much toxins had seeped into the food when the plastics were exposed to high heat. This is especially true if the food is packed in low quality plastic packaging that are not heat resistant enough.