what are the factors that determine when a substance is toxic and unfit for human consumption
Will become unfit for human consumption
This is already in effect nowadays. The FDA allows companies to sell genetically modified food, which theoretically is unfit for human consumption due to potential health reasons.
Horse chestnut
The phrase "Fit To Be Eaten" can be decribed as "edible". Fit for Consumption may be more appropriate. The opposite being "inedible" or "Unfit for Consumption"
methyl alcohol or methanol
meths - short for methylated spirits
In many of the dog/cat foods there are bi-products and that means organs, hooves, horns, etc., in the food. If the FDA isn't too fussy about what we eat (until recently) where do we think the animal food will be on the food chain.
Because the water which can be used is very less. Ocean water is salty and unfit for consumption.
Bleach will poison the crawfish, possibly rendering it unfit for human consumption, as well as pollute the environment.
Type II diabetes has been associated with the excessive consumption of sugary foods. I know this isn't a direct answer to your question, but NOT hyperactivity. There has been no proven correlation between hyperactive behavior in children and the consumption of sugary foods.
Yes