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.
One acre equals 0.0015625 square miles, 4,840 square yards, 43,560 square feet or about 4,047 square metres (0.4047 hectares) (see below). While all modern variants of the acre contain 4,840 square yards, there are alternative definitions of a yard, so the exact size of an acre depends on which yard it is based.