by Marion Nestle
Jul 29 2020

Don’t raise industrial chickens near orchards, please

For two years, the investigators took swab samples of soil surface, air, and leaves in an almond orchard 35 meters downwind from an industrial poultry farm.  They compared the samples to those collected from two almond orchards (controls) nowhere near a poultry operation.

E. coli was isolated from 41 of 206 (20%) and 1 of 207 (0.48%) air samples in the almond-poultry and control orchards, respectively….On average, the amount of dry solids on leaves collected from trees closest to the poultry operation was more than 2-fold greater than from trees 120 m into the orchard or from any of the trees in the control orchards.

Members of the family Staphylococcaceae—often associated with poultry—were, on average, significantly (P < 0.001) more abundant in the phyllosphere of trees closest to the poultry operation (10% of relative abundance) than in trees 120 m into the orchard (1.7% relative abundance) or from any of the trees in control orchards (0.41% relative abundance).

Poultry-associated microorganisms from a commercial operation transferred a short distance into an adjacent downwind almond orchard.

Contamination of leafy greens grown in California and Arizona near large cattle operations has been a problem for a long time.

This new study adds two pieces of information:

  • Toxic bacteria can travel downwind in air.
  • Poultry operations are just as contaminating as cattle operations.

The moral of this story: Do not grow nuts or fruit or vegetables near industrial meat or poultry operations.