It’s not just an “anything causes cancer” argument as others are trying to make it out to be. Out of 124 cancer patients who were primarily soccer players, 84 were goalies (meaning they had a lot more contact with the rubber than other players).
Ground up tire rubber is from old tires:
Tire rubber contains cobalt as part of the vulcanization process.
Tires drive thousands of miles on asphalt roads, can come in constant contact with anti freeze, oil, pesticides, anything found on roads or parking lots.
Athletic fields is one thing – playgrounds are more of a concern to me because of the likelihood of children ingesting this stuff. A family friend brought to my attention that Calgary (Alberta, Canada) had a similar issue almost a decade ago about lead in the grass of a residential area that was previously commercial zoned. It wasn’t safe for kids to play in that grass…
It was May of 1960 when turkeys in England started dying of a mysterious disease. By August, over 100,000 were dead — in some places, the mortality rate was 100%. Although pheasants and ducklings were also susceptible, turkey populations seemed most vulnerable, and so the plague got the name Turkey X Disease.
Fun fact! Aflatoxin isn’t inherently dangerous, in and of it itself. The compound has to first be activated by enzymes in your liver before it has carcinogenic action, resulting in inter-individual differences in susceptibility. Also, because the active compound is made in the liver, that’s where it does the most damage, aka liver damage and liver cancer. Aflatoxin B1 in particular is the most dangerous to humans, and if I recall correctly may be because it is more easily activated by human enzymes.