With water consumption increasing on every continent, the agricultural industry has an important issue in front of them: Will there continue to be enough water of suitable quality for agricultural production for the foreseeable future? Daniel Snow, director of the Nebraska Water Sciences Laboratory at University of Nebraska, posed this question at the IAFP annual meeting earlier this month.
Worldwide, it is estimated that the availability of freshwater (annual per capita) is just 1700 m3. According to the World Business Council for Sustainable Development, when this figure drops below 1000 m3 it puts pressure on not only on the economy but also on human health.
The amount of freshwater available for food production is limited (less than 3% of the world’s water is fresh). Further complicating the matter is the fact that this water comes from many different sources, and emerging contaminants are potentially everywhere. “We don’t really understand the effect [of these contaminants] on the environment or on human health,” said Snow. “We know the compounds occur in the water and likely occur in the food supply, but we don’t really understand the implications.”
According to Snow, there is very little regulation around water used for irrigation. Top concerns surrounding emerging contaminants include:
- Water reuse. Recycled wastewater contains traces of the following contaminants, which accumulate over time:
- Xenobiotics (organic compounds)
- Antibiotic-resistant bacteria/germs. Up to 90% of some of the antibiotics excreted are not metabolized by animals and humans
- Endocrine disrupters (steroids—natural and artificial in running water)
- Pharmaceuticals (both human and veterinary)
- Arsenic (namely related to rice production). The element is not only found in soil in Asia but also in soil in certain parts of the United States
- Co-occurrence of nitrate and uranium in ground water. There is growing evidence that uranium is being mobilized in water and one study has shown that uranium is readily taken up in food crops
It’s not all doom and gloom, said Snow. The upside to the issue: “We know enough now that we can start to understand the system and hopefully control the contaminants when producing food,” he said. The larger concern is determining which emerging contaminants pose the most significant problem.