Botulinum toxins are the most lethal toxins known. For type A toxin, the toxic dose is estimated at 0.001 mcg/kg (Franz 1997); the lethal dose for a 70-kg person by the oral route is estimated at 70 mcg, by the inhalational route 0.80 to 0.90 mcg, and by the intravenous route 0.09 to 0.15 mcg (Sobel 2005).
1 hectare = 2.47105381 acres. .07 hectare= .17 acres per person. about 7500 square feet per person. While this figure produces a result of around 5-6 people per acre, there are plenty of caveats to consider. If the soil is not ideal, increase the land. If the growing season is short, increase the land.
The result of this analysis is that the top 50 crops are sufficient to characterize the world agricultural system in its production of protein, fat, carbohydrates, and kcal for the world population. So, how many kcal does the global food system produce? Just over 10 16 kcal. How many kcal are needed to feed one billions persons? The answer, from my previous post, is 10 15 kcal â 10 6 kcal per person per year (2740 kcal per person per day) times 10 9 persons. So at 10 16 kcal, the world agricultural system produces enough kcal to feed 10 billion persons.