If you grew up on a farm, the first thing you were taught about fertilizer is that you can't use waste from anything that eats meat. Cows okay. Humans bad.

Researchers in Finland disagree and say that human urine is virtually sterile, free of bacteria or viruses and naturally rich in nitrogen and other nutrients.

Urine fertilization is rare today though they say it was common in ancient times. Maybe in Finland.

In the new study, Surendra K. Pradhan and colleagues collected human urine from private homes and used it to fertilize cabbage crops. Then they compared the urine-fertilized crops with those grown with conventional industrial fertilizer and no fertilizer.

The analysis showed that growth and biomass were slightly higher with urine than with conventional fertilizer.

There was no difference in nutritional value of the cabbage. "Our results show that human urine could be used as a fertilizer for cabbage and does not pose any significant hygienic threats or leave any distinctive flavor in food products," the report concludes.

- American Chemical Society.