Food

Water

City / Country

Reference

0.34-0.80

0.1

Cincinnati, Ohio/U.S.A.

Heyroth, 1954

0.94-1.16

2.0

Galesburg, Illinois/U.S.A.

Heyroth, 1954

1.32-1.35

5-6

Ennis, Texas/U.S.A.

Heyroth, 1954

0.99-2.19

6

Lake Preston, South Dakota/U.S.A.

Heyroth, 1954

2.33-3.13

8

Bartlett, Texas/U.S.A.

Heyroth, 1954

1.41-1.49

18

O'Donnell, Texas/U.S.A.

Heyroth, 1954

0.22-3.1

Norway

Danielson & Gaarder, 1956

0.6-1.2

Russia

Gabovich, 1951

0.18-0.3

Canada

Ham & Smith, 1950

0.5

Switzerland

Fellenberg, 1948

0.6-1.8

England

Longwell, 1957